Radionuclide imaging is used in patients who have new symptoms suggestive of metastasis.1 Bone scanning is performed in patients with known cancer to detect possible metastasis and is also conducted in patients for staging and subsequent treatment planning.
Population: Patients with cancer (limited to lung, prostate, and breast) undergoing staging and including patients with known cancer presenting with or without bone pain.
Intervention: Bone scanning, also known as bone scintigraphy, using technetium-99m–labelled methylene diphosphonate (99mTc-MDP).2
During a bone scan, the 99mTc-MDP is injected intravenously and accumulates in bone after several hours.3,4 A gamma camera is then used to detect "hot spots," which represent the areas of bone that have high metabolism or vasculature where the 99mTc has accumulated, such as in areas of bone metastasis.
Comparators: For this report, the following diagnostic tests are considered as alternatives to bone scanning:
Outcomes: Eleven outcomes (referred to as criteria) are considered in this report:
Definitions of the criteria are in Appendix 1.
The literature search was performed by an information specialist using a peer-reviewed search strategy.
Published literature was identified by searching the following bibliographic databases: MEDLINE with In-Process records and daily updates via Ovid; The Cochrane Library (2011, Issue 2) via Ovid; and PubMed. The search strategy consisted of both controlled vocabulary, such as the National Library of Medicine's MeSH (Medical Subject Headings), and keywords. The main search concepts were radionuclide imaging and bone tumours.
Methodological filters were applied to limit retrieval to health technology assessments, systematic reviews, meta-analyses, randomized controlled trials, and non-randomized studies, including diagnostic accuracy studies. Where possible, retrieval was limited to the human population and English-language documents. No date limits were applied for systematic reviews. For primary studies, the retrieval was limited to documents published between January 1, 2006, and March 14, 2011. Regular alerts were established to update the search until October 2011. See Appendix 2 for the detailed search strategies.
Grey literature (literature that is not commercially published) was identified by searching relevant sections of the CADTH Grey Matters checklist. Google and other Internet search engines were used to search for additional web-based materials. The searches were supplemented by reviewing the bibliographies of key papers. See Appendix 2 for more information on the grey literature search strategy.
Targeted searches were done as required for the criteria, using the aforementioned databases and Internet search engines. When no literature was identified that addressed specific criteria, experts were consulted.
Thirty-one potential articles were identified through the health technology assessment/systematic review/meta-analysis (HTA/SR/MA) filtered search and 12 were subjected to full-text review. A total of 380 potential primary studies were identified with the primary studies search. Additional studies were identified in searches for grey literature, targeted searches, and alerts.
For criterion 7 on diagnostic accuracy, systematic reviews were included. In addition, primary studies published between 2006 and 2011 that were not included in any of the systematic reviews were summarized individually. In total, six systematic reviews5-10 and five primary studies11-15 were included for criterion 7.
For all the remaining criteria, included studies were not limited by study design or date, and were obtained from the HTA/SR/MA search, grey literature searching, a primary studies search, targeted searching, and handsearching.
Domain 1: Criteria Related to the Underlying Health Condition | |||||||||||||||||
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Criterion | Synthesized Information | ||||||||||||||||
1 | Size of the affected population |
The estimated number of new cases of breast, prostate, and lung cancer in 2011 is tabulated. Based on data from a population-based analysis of approximately 100,000 women with breast cancer and 125,000 men with prostate cancer, the incidence of bone metastasis at diagnosis or during follow-up (median 3.3 years) was 7.3%16 and 7.7%,17 respectively. Similar data were not available for lung cancer. Studies have reported an incidence of bone metastases of approximately 30% for patients with non–small cell lung cancer.18 Using these data, the possible number of cases of metastasis was estimated.
*Calculated from estimated new cases and the reported rates of bone metastasis for each type of cancer.20 Notably, these patients would undergo repeat imaging if there is suggestion that there was disease progression to the bone. Therefore, each patient could receive multiple scans. Given this, the size of the affected population is estimated to be more than 1 in 1,000 (0.1%) and less than or equal to 1 in 100 (1%). |
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2 | Timeliness and urgency of test results in planning patient management | Imaging to detect bone metastases required for staging to plan treatment and follow-up. Benchmark wait times for bone scan and PET are immediate to 24 hours for an emergency case, within 7 days for an urgent case, and within 30 days for a scheduled case.21 Patient management (i.e., surgery, chemotherapy, radiation) depends on imaging findings. A delay in test results may have a negative effect on the workflow.
The target time frame for performing the test is between 8 and 30 days, and obtaining the test results has significant impact on the management of the condition or the effective use of health care resources. |
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3 | Impact of not performing a diagnostic imaging test on mortality related to the underlying condition | The estimated 5-year relative survival ratio (for the period 2004-2006) is 88%, 96%, and 19% for breast, prostate, and lung cancer, respectively.
If an imaging test was not performed, staging information cannot be obtained and treatment cannot be appropriately planned. However, if the test was performed, there is ultimately no impact on mortality. |
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4 | Impact of not performing a diagnostic imaging test on morbidity or quality of life related to the underlying condition | Imaging is required for accurate staging of disease and for selecting the appropriate treatment. Without accurate staging information, patients may receive less aggressive treatment (e.g., a patient with clinical stage I or II disease who would have been restaged to stage III with imaging findings and, subsequently, managed differently) or more aggressive treatment (e.g., surgery being unnecessarily performed on a patient who would not benefit from it, based on diagnostic imaging information — for instance, if they had metastatic disease that has spread throughout the body, which would have been detected by imaging).
Diagnostic imaging test results can have a significant impact on morbidity or quality of life. |
Domain 2: Criteria Comparing 99mTc with an Alternative or Comparing Between Clinical Uses | ||||||||||||||||||||||||||||||||||||||||||||||||||||
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Criterion | Synthesized Information | |||||||||||||||||||||||||||||||||||||||||||||||||||
5 | Relative impact on health disparities | To be scored locally. | ||||||||||||||||||||||||||||||||||||||||||||||||||
6 | Relative acceptability of the test to patients | Bone scanning: Limited information was identified on the acceptability to patients of bone scanning with 99mTc-MDP. Patients may have concerns about radiation exposure and the intravenous injection of radiopharmaceutical agent.
PET: Patients are required to fast prior to an 18FDG-PET scan. The level of acceptability to patients of bone scanning with 99mTc-radiolabelled isotopes:
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7 | Relative diagnostic accuracy of the test |
The sensitivity and specificity of bone scanning, 18FDG-PET, and 18F-PET were reported in 6 systematic reviews and 5 observational studies. For the modality of PET, all of the included studies used the pharmaceutical 18FDG. No primary studies were identified for inclusion (which were not already included in a systematic review) that used 18F. The data are sum
marized according to cancer type. CT = computed tomography; 18FDG-PET = 18-fluorodeoxyglucose positron emission tomography. No information was available regarding the diagnostic accuracy of bone scanning and other imaging techniques according to cancer stage. Overall, with respect to breast cancer, the diagnostic accuracy of bone scanning with 99mTc-radiolabelled isotopes is:
Overall, with respect to prostate cancer, based on feedback from MIIMAC, the diagnostic accuracy of bone scanning with 99mTc-radiolabelled isotopes is:
Overall, with respect to lung cancer, the diagnostic accuracy of bone scanning with 99mTc-radiolabelled isotopes is:
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8 | Relative risks associated with the test |
Non–radiation-related Risks Patients may experience soreness and swelling at the site of injection of the 99mTc, and there is a small risk of cell or tissue damage due to the radiation. Some patients may have difficulty lying still during the test.4,22 Although rare, allergic reactions to MDP are possible.23 Radiation-related Risks The radiation dose for bone scans is lower than that of 18FDG-PET/CT.10 Radiation doses for the modalities used in bone tumour imaging are tabulated.
mSv = millisievert; PET = positron emission tomography. Overall, the safety profile of bone scanning with 99mTc-radiolabelled isotopes is:
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9 | Relative availability of personnel with expertise and experience required for the test |
Interobserver agreement of bone scans has been reported as moderate,29,30 Another study reported good agreement for bone scanning and 18FDG-PET/CT.31 As of 2006 in Canada, there were 2,034 diagnostic radiologists; 221 nuclear medicine physicians; 12,255 radiological technologists; 1,781 nuclear medicine technologists, and 2,900 sonographers available across Canada. The Territories do not have the available personnel to perform and interpret tests to detect bone metastases. Other jurisdictions (e.g., PEI) may offer limited nuclear medicine services. Assuming the necessary equipment is available, if bone scanning with 99mTc radiolabelled isotopes is not available, it is estimated that:
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10 | Accessibility of alternative tests (equipment and wait times) | Wait times Wait times for urgent bone scan ranged from 1 to 6 days, and for scheduled scans ranged from 7 to 73 days.32 Equipment Assuming personnel with the necessary expertise and experience are available, if bone scanning with 99mTc-radiolabelled isotopes is not available, it is estimated that:
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11 | Relative cost of the test |
According to our estimates, the cost of whole body bone scan with 99mTc-based radioisotopes is $278.70. 18F-PET and 18FDG-PET are significantly more costly alternatives.
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CT = computed tomography; 18FDG-PET = 18-fluorodeoxyglucose positron emission tomography; mSv = millisievert; PET = positron emission tomography; 99mTc-MDP = 99mtechnetium-labelled methylene diphosphonate; 99mTc = technetium-99m.
Criterion 1: Size of affected population (link to definition)
Bone is a common site of metastasis, and the most common types of tumours to metastasize to bone are breast, prostate, lung, kidney, and thyroid.34 The estimated numbers of new cases of breast, prostate, and lung cancer in 2011 are tabulated. Based on data from a population-based analysis of approximately 100,000 women with breast cancer and 125,000 men with prostate cancer, the incidence of bone metastasis at diagnosis or during follow-up (median 3.3 years) was 7.3%16 and 7.7%,17 respectively. Similar data were not available for lung cancer. Studies have reported an incidence of bone metastases of approximately 30% for patients with non–small cell lung cancer (NSCLC).18 Using the estimated number of new cases reported by the Canadian Cancer Society (CCS) for 2011,19 and these reported rates of metastasis, Table 2 reports the estimated number of cases of bone metastasis per 100,000 people.
Cancer Type | 2011 Estimated Number of New Cases/100,00019 | Estimated Number of Cases of Bone Metastasis per 100,000* |
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Breast | 102† (0.102%) | 7.4 (0.0074%) |
Prostate | 122 (0.122%) | 9.4 (0.0094%) |
Lung | 57 (0.057%) | 17.1 (0.0171%) |
*Calculated from estimated new cases and the reported rates of bone metastasis for each type of cancer.16-18
†Females only.
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Criterion 2: Timeliness and urgency of test results in planning patient management (link to definition)
Imaging to detect bone metastases is needed to enable treatment planning and follow-up.20 Pain and quality of life have been reported to improve in prostate cancer patients with bone metastasis who are treated with hormonal therapy or bisphosphonates.20,35 In patients with breast cancer, detection of metastases may prevent complications and control disease progression.7
A study in patients with myxoid liposarcoma, which commonly metastasizes to the spine, reported the effects of treatment following detection of spinal metastasis.36 Thirty-three patients with detected spinal metastasis were treated with either radiation alone (n = 8), surgery and radiation (n = 14), surgery alone (n = 4), or did not receive treatment (n = 7). Treatment with surgery and radiation improved pain scores in all patients with reported pain. In addition, two patients who were treated (one with surgery alone, one with surgery and radiation) were disease free at long-term follow-up. All patients who were untreated were either no longer alive, or alive with disease. This study concluded that diagnosis of bone metastasis and early treatment can improve outcomes such as controlling pain.
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Criterion 3: Impact of not performing a diagnostic imaging test on mortality related to the underlying condition (link to definition)
Data from the 2011 Canadian Cancer Society Statistics reported that the estimated five-year relative survival ratio (for the period 2004 to 2006) is 88%, 96%, and 19% for breast, prostate, and lung cancer, respectively. Survival ratios are influenced significantly by the stage of disease.19
If an imaging test was not performed, staging information cannot be obtained and treatment cannot be appropriately planned. Diagnostic imaging test results can have a moderate impact on mortality.
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Criterion 4: Impact of not performing a diagnostic imaging test on morbidity or quality of life related to the underlying condition (link to definition)
Bone metastasis has been reported to be associated with pain, hypercalcemia, nerve compression, fractures, and disability.7,20,37 Detection and subsequent treatment of bone metastasis can improve outcomes such as pain and quality of life.
Imaging is required for accurate staging of disease and for selecting the appropriate treatment. Without accurate staging information, patients may receive less aggressive treatment (e.g., a patient with clinical stage I or II disease who would have been restaged to stage III as a result of imaging findings and, subsequently, managed differently) or more aggressive treatment (e.g., surgery being unnecessarily performed on a patient who would not benefit from it, based on diagnostic imaging information — for instance, if they had metastatic disease that has spread throughout the body, which would have been detected by imaging).
Diagnostic imaging test results can have a significant impact on morbidity or quality of life.
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Criterion 5: Relative impact on health disparities (link to definition)
A 2005 study reported that diagnostic imaging tests were conducted more frequently in patients with a higher socioeconomic status than those with a lower socioeconomic status.38
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Criterion 6: Relative acceptability of the test to patients (link to definition)
Bone scanning
Patients, or parents of patients, may have concerns about radiation exposure and the intravenous injection of radiopharmaceutical agent. Limited information was identified on the acceptability of bone scanning to pediatric patients. A retrospective study on the use of bone scanning in children with osteosarcoma or Ewing sarcoma suggested that any test, including a bone scan, causes psychological strain on the children and the parents.39
18F or 18FDG-PET
Patients may have concerns about radiation exposure and the intravenous injection of radiopharmaceutical agent. Patients undergoing 18FDG-PET are required to fast prior to the scan.
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Criterion 7: Relative diagnostic accuracy of the test (link to definition)
Based on the American College of Radiology Appropriateness Criteria,40-42 the following whole body bone scans using 99mTc are "usually appropriate" or "may be appropriate" for the following indications:
Breast cancer
Prostate cancer
Lung cancer
See Appendix 3 for more information regarding the ACR Appropriateness Criteria applicable to bone tumour imaging.
Breast Cancer
For patients with breast cancer, three systematic reviews5-7 and three observational studies11,12,43 were included that compared the diagnostic accuracy of bone scan for detecting bone metastases with either 18FDG-PET or 18FDG-PET/CT.
Systematic reviews and meta-analyses
A 2011 systematic review and meta-analysis compared bone scan, 18FDG-PET, and magnetic resonance imaging (MRI) for detection of bone metastasis.5 Databases were searched between 1995 and 2010, without any restriction on language. Studies were included that used 18FDG-PET, MRI, or bone scan with 99mTc-MDP to identify bone metastases in patients with breast cancer; used histopathological analysis or imaging and clinical follow-up as the reference standard; and reported per-patient or per-lesion data that could be used to calculate measures of diagnostic accuracy. Studies of children, case reports, letters, editorials, and reviews were excluded, as were studies that used radiopharmaceuticals other than 18FDG or 99mTc-MDP (e.g., technetium-99m-hexakismethoxy-isobutyl-isonitril [99mTc-MIBI] bone scan). Quality of the included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) instrument and only those with a score of 9 or higher were included.
The study characteristics for included articles were not published. This information was requested, but not received. Table 3 reports the sensitivity and specificity of the imaging tests on a per-patient and per-lesion basis. The authors described the quality of the included studies as suboptimal, due to issues with the reference standard and blinding of the individuals interpreting images. Overall, the study concluded that on a per-patient basis, MRI was more effective at detecting bone metastases in breast cancer patients compared with 18FDG-PET or bone scan, whereas 18FDG-PET had lower sensitivity than bone scanning on a per-lesion basis. However, further information regarding the patient characteristics should be considered.
Test | Sensitivity (95% CI) | Specificity (95% CI) | Sensitivity (95% CI) | Specificity (95% CI) |
Patient Basis | Lesion Basis | |||
Bone scan | 87.0 (82.1 to 90.9) | 88.1 (84.6 to 91.0) | 87.8 (83.9 to 91.1) | 96.1 (94.7 to 97.2) |
MRI | 97.1 (90.1 to 99.7) | 97.0 (89.5 to 99.6) | NS | NS |
18FDG-PET | 83.3 (78.2 to 90.8) | 94.5 (88.5 to 98.0) | 52.7 (47.0 to 58.4) | 99.6 (98.9 to 99.0) |
CI = confidence interval; 18FDG =18F fluorodeoxyglucose; MRI = magnetic resonance imaging; NS = no studies; PET = positron emission tomography.
In a 2010 systematic review, Escalona et al.6 evaluated the use of 18FDG-PET in breast cancer. One objective was to evaluate the accuracy of 18FDG-PET in detecting metastases. Studies that compared the diagnostic accuracy of 18FDG-PET with a reference test in patients with breast cancer were included. Health technology assessments, systematic reviews, meta-analyses, and observational and experimental studies were eligible for inclusion. Studies that included mixed cancer populations (in which data for breast cancer were not reported separately) were excluded. There was no limitation on the search time frame, which ran until February 2007. The quality of the included studies was assessed using a checklist for diagnostic studies.
In total, 73 studies were included in the systematic review, eight of which evaluated 18FDG-PET compared with bone scan in the detection of bone metastases. A total of 382 patients were included across the eight studies. The quality of the included studies was described as low, due to small sample sizes, failure to report on blinding of the individual interpreting images, use of multiple PET scanners and provision of only aggregate results, and the inclusion of patients with different tumour stages without presenting results according to stage. The authors of the systematic review did not pool diagnostic accuracy data across studies and were unable to report results according to tumour stage, given the available data. No patient characteristics were reported for the individual studies, making it unclear as to whether patients were symptomatic or asymptomatic.
The sensitivity of both 18FDG-PET and bone scan in detecting bone metastases ranged from 77.7% to 100%. The specificity of 18FDG-PET ranged from 88.2% to 100%, while the specificity of bone scan ranged from 80% to 100%. The positive predictive value (PPV) and negative predictive value of 18FDG-PET were reported in only one study, and were 85.7% and 95.8%, respectively, compared with 70.6% and 95.2%, respectively, for bone scan. Estimates of the accuracy of 18FDG-PET ranged from 83.1% to 97.7% and 78.7% to 93.2% for bone scan. It was unclear if the results presented were on a patient or lesion basis. The authors concluded that 18FDG-PET appears to be more specific than bone scan in detecting bone metastases in patients with breast cancer, but should not be used in isolation.
Shie et al. published a systematic review and meta-analysis in 2008 comparing 18FDG-PET and bone scans to detect bone metastasis.7 Studies including breast cancer patients who underwent both 18FDG-PET and bone scans within three months of one another, with positive finding confirmed by CT, MRI, or biopsy, were included. Patients of all stages were included (no breakdown was provided). In addition, it was not stated if the patients had symptoms of bone metastasis. Formal quality assessment of the included studies did not appear to be performed.
Six studies were included in the analysis. On a patient basis (184 patients from three studies), the pooled sensitivity was 81% for 18FDG-PET and 78% for bone scan, and specificity was 93% for 18FDG-PET and 79% for bone scan. On a lesion basis (1,207 patients from four studies), the sensitivity was 69% and 88%, and the specificity was 98% and 87% for 18FDG-PET and bone scan, respectively. The authors concluded that it is unclear which modality is superior for detection of bone metastasis in patients with breast cancer, but 18FDG-PET may be a more useful confirmatory test due to its higher specificity.
Observational studies
Two observational studies were identified that evaluated the diagnostic performance of bone scan relative to another imaging modality for the detection of bone metastases in patients with breast cancer.11,12 These studies were not included in any of the three systematic reviews and are summarized individually in Tables 13 and 14 in Appendix 4. Bone scan with 99mTc-MDP was compared with 18FDG-PET/CT11 and 18FDG-PET12 (Appendix 4, Table 13). One study was a prospective cohort study12 and the second was a retrospective cohort study.11 Both studies were conducted in the United States. 11,12 It was unclear in either of the studies if the patients were symptomatic or asymptomatic, but patients in these studies were either high risk for metastases or were suspected of having metastases.11,12
Neither of the two studies reported outcomes according to cancer stage. In one study, the concordance between bone scan and 18FDG-PET/CT was 81% (Appendix 4, Table 14).11 Sensitivity and specificity were not reported in this study. In the second study, the sensitivity of conventional imaging (bone scan and CT) and 18FDG-PET was equivalent (80%), while the specificity was greater with 18FDG-PET than with conventional imaging (94% versus 79%).12 Conclusions and limitations of the individual studies can be found in Appendix 4, Table 14.
Lung Cancer
For patients with lung cancer, one systematic review8 and two observational studies13,14 were included that compared the diagnostic accuracy of bone scan in detecting bone metastases with either 18FDG-PET or 18FDG-PET/CT.
Systematic reviews and meta-analyses
Bone scan, MRI, and 18FDG-PET for detecting bone metastasis in patients with lung cancer were compared in a systematic review and meta-analysis published in 2011.8 Databases were searched between 1995 and 2010, without any restriction on language. Studies were included that used 18FDG-PET or bone scan with 99mTc-MDP to detect bone metastases in patients with lung cancer; reported per-patient or per-lesion data that could be used to calculate measures of diagnostic accuracy. Clinical follow-up, imaging follow-up, histopathological analysis, or radiographic confirmation were used as reference standards. Studies of children, case reports, letters, editorials, and reviews were excluded, as were studies that used radiopharmaceuticals other than 18FDG or 99mTc-MDP (e.g., 99mTc-MIBI bone scan). Quality of the included studies was assessed using the QUADAS instrument and only those with a score of 9 or higher were included. The study characteristics for included articles were not published. This information was requested, but not received.
Fourteen articles that in total reported data on 5,676 patients were included in the analysis. Issues with study quality were identified, mainly with regard to the reference standard and blinding of the individual interpreting images. Table 4 reports the sensitivity and specificity of the three modalities on a per-patient and per-lesion basis. 18FDG-PET was reported to have better diagnostic accuracy than MRI or bone scanning. The authors concluded that 18FDG-PET is superior for detecting bone metastasis in patients with lung cancer. However, further information regarding the patient characteristics should be considered.
Test | Sensitivity (95% CI) | Specificity (95% CI) | Sensitivity (95% CI) | Specificity (95% CI) |
Patient Basis | Lesion Basis | |||
Bone scan | 91.8 (89.1 to 94.1) | 68.8 (65.8 to 71.6) | 71.5 (66.9 to 75.8) | 91.0 (89.2 to 92.7) |
MRI | 80.0 (67.0 to 89.6) | 90.6 (85.8 to 94.3) | 83.8 (77.0 to 89.2) | 96.3 (95.3 to 97.1) |
18FDG-PET | 91.9 (88.8 to 94.3) | 96.8 (96.0 to 97.6) | 95.0 (93.5 to 96.2) | 94.6 (93.5 to 95.5) |
CI = confidence interval; 18FDG =18F fluorodeoxyglucose; MRI = magnetic resonance imaging; PET = positron emission tomography.
Observational studies
Two observational studies, one in patients with NSCLC and one in patients with small cell lung cancer (SCLC), were identified that evaluated the diagnostic performance of bone scan relative to 18FDG-PET13 or 18FDG-PET/CT14 for preoperative staging. These studies are summarized in Tables 13 and 14 in Appendix 4. Bone scan was performed with 99mTc-labelled oxydronate in one study,14 while the radiopharmaceutical used in the other study was not specified.13 Both studies used prospective cohort designs. One was conducted in Italy13 and one was conducted in Denmark.14 It was unclear if patients in the two studies were symptomatic or asymptomatic.
Outcomes were not reported according to cancer stage. In patients with NSCLC, the sensitivity of bone scan was 67% compared with 96% with 18FDG-PET, while the specificity of bone scan was 94% compared with 99% with 18FDG-PET. For patients with SCLC, the sensitivity of bone scan was 75% but was not reported for 18FDG-PET/CT.14 In 17% of patients, 18FDG-PET/CT suggested a different stage than conventional staging.14 Conclusions and limitations of the individual studies can be found in Appendix 4, Table 14.
Prostate Cancer
Observational studies
One US-based prospective cohort observational study was identified that evaluated the diagnostic performance of bone scan relative to 18FDG-PET for the detection of bone metastases in patients with prostate cancer.15 Further information on this study is available in Tables 13 and 14 in Appendix 4.
Outcomes were not reported according to cancer stage. The authors reported that 18FDG-PET/CT detected bone metastases in 72.1% of patients compared with 86.1% with bone scan (P = 0.01) (Appendix 4, Table 14).15 Conclusions and limitations can be found in Appendix 4, Table 14.
Studies Involving Multiple Cancer Types
A systematic review and meta-analysis published in 2011 compared 18FDG-PET/CT with bone scintigraphy in the detection of bone metastases in patients with malignancies.9 English-language studies published between 2000 and 2010 were eligible for inclusion if they compared 8FDG-PET/CT with bone scan in patients of any age or disease stage; presented sufficient data to calculate measures of diagnostic accuracy; used histopathological follow-up, clinical follow-up, and/or combined imaging as the reference test; and reported on at least six patients. Study quality was assessed using the QUADAS instrument.
Six studies involving a total of 1,560 patients were included in the meta-analysis. Three studies were prospective and three were retrospective. Patient-based data were reported in five studies, while lesion-based data were reported in one. Three studies included only patients with NSCLC, one study included patients with either NSCLC or SCLC, one study included patients with nasopharyngeal cancer, and one study included patients with Ewing sarcoma, ganglioneuroblastoma, rhabdomyosarcoma, neuroblastoma, or granulocytic sarcoma. Of the 1,560 patients, 1,341 had NSCLC. Details on cancer stage or whether patients were symptomatic were not reported.
The authors described all studies as being of moderate quality and reported that the main weakness in the included studies involved the reference standard, which was not independent of the index test or not the same for all patients. Table 5 reports the sensitivity and specificity of the imaging methods on a per-patient basis. The authors concluded that the pooled sensitivity and specificity of 18FDG-PET/CT were higher than bone scan, but that further research was required to evaluate 18FDG-PET/CT in other malignancies such as breast and prostate cancer.
Test | Sensitivity (95% CI) | Specificity (95% CI) |
Bone scan | 0.71 (0.64 to 0.76) | 0.91 (0.90 to 0.93) |
18FDG-PET/CT | 0.93 (0.89 to 0.96) | 0.98 (0.97 to 0.98) |
CI = confidence interval; 8FDG = 18F fluorodeoxyglucose; PET/CT = positron emission tomography/computed tomography.
A systematic review and meta-analysis published in 201010 reported the diagnostic accuracy of 18FDG-PET, 18FDG-PET/CT, bone scan, and bone scan plus single-photon emission computed tomography (SPECT) for detecting bone metastasis. Eleven studies involving 425 patients were included in the analysis and studies were characterized based on whether patients were analyzed on a patient basis (350 patients) or a lesion basis (255 patients). The population included patients with lung cancer, prostate cancer, breast cancer, and hepatocellular carcinoma, and it was not reported in six of the included studies. The reference standard varied across the 11 studies, and included CT, MRI, radiography, 18FDG-PET, clinical follow-up, or biopsy. Table 6 reports the sensitivity and specificity of the imaging methods. Some studies combined the findings from PET and PET/CT or bone scan and bone scan plus SPECT. Only the results of the individual tests are included in Table 6.
Test | Sensitivity (95% CI) | Specificity (95% CI) | Sensitivity (95% CI) | Specificity (95% CI) |
Patient Basis | Lesion Basis | |||
BS | 0.468 (0.398 to 0.537) | 0.883 (0.829 to 0.936) | 0.579 (0.526 to 0.632) | 0.954 (0.924 to 0.984) |
BS + SPECT | 0.815 (0.706 to 0.923) | 0.990 (0.973 to 1.000) | 0.357 (0.198 to 0.516) | 0.961 (0.921 to 1.000) |
18FDG-PET | 0.949 (0.912 to 0.986) | 0.987 (0.972 to 1.000) | 0.958 (0.942 to 0.974) | 0.983 (0.969 to 0.996) |
18FDG-PET/CT | 0.977 (0.938 to 1.000) | 0.959 (0.905 to 1.000) | 0.978 (0.964 to 0.991) | 0.978 (0.966 to 0.990) |
BS = bone scan; CI = confidence interval; CT = computed tomography; 18FDG =18F fluorodeoxyglucose; PET = positron emission tomography; SPECT = single-photon emission computed tomography.
Overall, the sensitivity and specificity of 18FDG-PET and 18FDG-PET/CT were higher for detection of bone metastasis compared with bone scan with or without SPECT. The authors concluded that 18FDG-PET or PET/CT can be substituted for bone scanning with 99mTc during a supply shortage. The radiation dose was reported to be higher for 18FDG-PET and PET/CT (range: 2.7 to 28 mSv) than bone scans (range: 4.2 to 5.7 mSv), and therefore should be a consideration. A major limitation of this report is that it was not stated whether the patients with known cancer were symptomatic/asymptomatic or if imaging was being conducted for staging purposes. The list of included studies evaluated patient populations that are likely very different. For example, one study evaluated bone imaging in high-risk prostate cancer patients and another in newly diagnosed lung cancer patients.
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Criterion 8: Relative risks associated with the test (link to definition)
Non-radiation Risks
Bone scanning
Several studies44-47 reported mild adverse events with 99mTc-labelled tracers (e.g., skin reactions) and one case report published in 1985 reported a patient who experienced a rash following two bone scans with 99mTc-MDP, one in 1983 and one the following year.23 The authors concluded this patient had an allergic reaction to MDP on both occasions. This case report references an older study that reported 22 adverse reactions to 99mTc-MDP, in which 20 of the reactions were either "probably" or "possibly" caused by MDP.
PET
The Pharmacopeia Committee of the Society of Nuclear Medicine conducted a four-year prospective evaluation of adverse reactions to PET and reported no adverse reactions among the 33,925 scans conducted in 22 participating PET centres in the United States.48
Radiation Exposure
Among the modalities available for bone tumour imaging, bone scanning and PET expose the patient to ionizing radiation. The average effective dose of radiation delivered with each of these procedures is shown in Table 7. For comparison, the average effective dose of natural background radiation to which individuals are exposed over a year duration is 3.0 mSv.28
The radiation dose reported in the systematic review by Tateishi et al. was lower for bone scans (4.2 to 5.7 mSv) than 18FDG-PET and PET/CT (2.7 to 28 mSv).10 Another study reported that the calculated dose of radiation for a bone scan is 5 to 6 mSv.39
Procedure | Average Effective Dose (mSv) |
Bone scan | 6.3 |
Whole body PET | 14.1 |
Average background dose of radiation per year | 1 to 3.026-28 |
CT = computed tomography; mSv = millisievert; PET = positron emission tomography.
Return to Summary Table
Criterion 9: Relative availability of personnel with expertise and experience required for the test (link to definition)
Expertise
Reliability of the interpretation of bone scans (or other diagnostic imaging tests) by different readers (interobserver agreement) is routinely assessed using the kappa (?) score — a measure of agreement beyond that expected by chance alone.49 A kappa score of less than 0.20 means poor agreement, 0.21 to 0.40 fair agreement, 0.41 to 0.60 moderate agreement, 0.61 to 0.80 good agreement, and 0.81 to 1.00 very good agreement.50
Interobserver agreement of bone scans was compared in a retrospective study published in 2008 of 59 breast and prostate cancer patients.29 Thirty-seven physicians with daily experience in reading bone scans were involved in the study. Clinical examination (including bone scan results, laboratory results, other diagnostic tests, and follow-up examination) of all patients by the same experienced physician was used as the gold standard. Pairwise comparisons between two different examiners were calculated for 666 pairs. The mean kappa coefficient between the observers was 0.48, which is classified as a "moderate" level of agreement. The mean kappa coefficient for inexperienced observers compared with the gold standard was 0.40, and the moderately experienced and experienced observers had a mean kappa coefficient of 0.51.
Interobserver agreement was also reported in the study by Balliu et al.30 The agreement between two observers for bone scanning was low for a four-point scale (kappa index = 0.260) but moderate on a two-point scale (kappa index = 0.524). Takenaka et al.31 also reported interobserver agreement between tests. The kappa index was 0.67 for bone scanning and 0.65 for 18FDG-PET/CT, indicating substantial agreement with either test.
Personnel
Bone scintigraphy
In Canada, physicians involved in the performance, supervision, and interpretation of bone scans should be nuclear medicine physicians or diagnostic radiologists with training/expertise in nuclear imaging.51 Physicians should have a Fellowship of Certification in Nuclear Medicine or Diagnostic Radiology with the Royal College of Physicians and Surgeons of Canada and/or the Collège des médecins du Québec. Nuclear medicine technologists are required to conduct bone scans. Technologists must be certified by the Canadian Association of Medical Radiation Technologists (CAMRT) or an equivalent licensing body.
All alternative imaging modalities
Service engineers are needed for system installation, calibration, and preventive maintenance of the imaging equipment at regularly scheduled intervals. The service engineer's qualification will be ensured by the corporation responsible for service and the manufacturer of the equipment used at the site.
Qualified medical physicists (on site or contracted part-time) should be available for the installation, testing, and ongoing quality control of nuclear medicine equipment.51
PET
In Canada, physicians involved in the performance, supervision, and interpretation of PET scans should be nuclear medicine physicians or diagnostic radiologists with training/expertise in nuclear imaging. Physicians should have a Fellowship of Certification in Nuclear Medicine or Diagnostic Radiology with the Royal College of Physicians and Surgeons of Canada and/or the Collège des médecins du Québec. Technologists must be certified by CAMRT or an equivalent licensing body.
A summary of the availability of personnel required for the conduct of bone tumour imaging, by bone scanning or any of the alternative imaging modalities, is provided in Table 8.
Jurisdiction | Diagnostic Radiology Physicians | Nuclear Medicine Physicians | Nuclear Medicine Technologists | Medical Physicists |
---|---|---|---|---|
NL | 46 | 3 | 15 | NR |
NS | 71 | 5 | 71 | NR |
NB | 47 | 3 | 55 | NR |
PEI | 7 | 0 | 3 | 0 |
QC | 522 | 90 | 460 | NR |
ON | 754 | 69 | 693 | NR |
MB | 58 | 8 | 42 | NR |
SK | 61 | 4 | 36 | NR |
AB | 227 | 18 | 193 | NR |
BC | 241 | 21 | 212 | NR |
YT | 0 | 0 | 0 | 0 |
NWT | 0 | 0 | 1 | 0 |
NU | 0 | 0 | 0 | 0 |
Total | 2,034 | 221 | 1,781 | 322* |
AB = Alberta; BC = British Columbia; MB = Manitoba; NB = New Brunswick; NL = Newfoundland and Labrador; NR = not reported by jurisdictions; NS = Nova Scotia; NU = Nunavut; NWT= Northwest Territories; ON = Ontario; PEI = Prince Edward Island; QC = Quebec; YT = Yukon.
*This represents a total for all of the jurisdictions.
Return to Summary Table
Criterion 10: Accessibility of alternative tests (equipment and wait times) (link to definition)
Wait Times
Wait-time benchmarks were reported by the Canadian Medical Association for the Wait Time Alliance (WTA) in 2005.21 For bone scanning and 18FDG-PET, the wait-time benchmark was immediate to 24 hours for an emergency case, within seven days for an urgent case, and within 30 days for a scheduled case. The WTA reported wait times for urgent bone scan as ranging from one to six days throughout the provinces, and for scheduled cases, the range was seven to 73 days.32
Equipment
There are notable variations in the availability of medical imaging technologies within hospitals across Canada. Nuclear medicine cameras are not available in the Yukon, the Northwest Territories, and Nunavut. Table 9 provides an overview of the availability of equipment required to imaging bone metastases. Data for nuclear medicine cameras (including SPECT) are current to January 1, 2007. The number of SPECT/CT scanners is current to January 1, 2010. Information on the availability of PET and PET/CT scanners is current to November 30, 2010.
Bone scanning
For bone scintigraphy, nuclear medicine facilities with gamma cameras (including SPECT) are required. Three jurisdictions — the Yukon, the Northwest Territories, and Nunavut — do not have any nuclear medicine equipment.52
PET
A 2010 Environmental Scan published by CADTH reported that approximately 31 Canadian centres are equipped to perform PET scans.33 These centres are located in the provinces of British Columbia, Alberta, Manitoba, Ontario, Quebec, New Brunswick, and Nova Scotia.33 There are 36 PET or PET/CT scanners, four of which are used for research purposes only.33
Nuclear Medicine Cameras | SPECT/CT Scanners | PET or PET/CT Scanners | |
---|---|---|---|
Number of devices | 60352 | 9653 | 3633 |
Average number of hours of operation per week (2006-2007)52 | 40 | NA | NA |
Provinces and Territories with no devices available | YT, NT, NU | PEI, YT, NT, NU | NL, PEI, SK, YT, NT, NU |
NA = not available; NS = Nova Scotia; NT = Northwest Territories; NU = Nunavut; PEI = Prince Edward Island; YT = Yukon.
Return to Summary Table
Criterion 11: Relative cost of the test (link to definition)
Fee codes from the Ontario Schedule of Benefits were used to estimate the relative costs of bone scanning and its alternatives. Technical fees are intended to cover costs incurred by the hospital (i.e., radiopharmaceutical costs, medical/surgical supplies, and non-physician salaries). Maintenance fees are not billed to OHIP — estimates here were provided by St. Michael's Hospital in Toronto. Certain procedures (i.e., PET scan) are paid for, in part, out of the hospital's global budget; these estimates were provided by The Ottawa Hospital. It is understood that the relative costs of imaging will vary from one institution to the next.
According to our estimates (Table 10), the cost of whole body bone scan with 99mTc-based radioisotopes is $278.70. 18F-PET and 18FDG-PET are significantly more costly alternatives.
Fee Code | Description | Tech. Fees ($) | Prof. Fees ($) | Total Costs ($) |
---|---|---|---|---|
Whole Body Bone Scan | ||||
J850 | Bone scintigraphy — general survey | 106.35 | 62.80 | 169.15 |
J866 | Application of tomography (SPECT), maximum one per nuclear medicine examination | 44.60 | 31.10 | 75.70 |
Maintenance fees — global budget | 33.85 | 33.85 | ||
TOTAL | 184.80 | 93.90 | 278.70 | |
18F-PET | ||||
J706 | NSCLC | 250.00 | 250.00 | |
Technical cost — from global budget | 600.00 | 600.00 | ||
TOTAL | 600.00 | 250.00 | 850.00 | |
18FDG-PET | ||||
J706 | NSCLC | 250.00 | 250.00 | |
Technical cost — from global budget | 800.00 | 800.00 | ||
TOTAL | 800.00 | 250.00 | 1,050.00 |
CT = computed tomography; 18F = 18F-fluoride; 18FDG = 18F-fluorodeoxyglucose; NSCLC = non–small cell lung cancer; PET = position emission tomography; prof = professional; SPECT = single-photon emission computed tomography; tech. = technical.
Return to Summary Table
OVERVIEW | |||
Interface: | Ovid | ||
Databases: | Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations
Ovid MEDLINE(R) Daily and Ovid MEDLINE(R) 1946 to Present EBM Reviews - Cochrane Database of Systematic Reviews 2005 to February 2011 EBM Reviews - Database of Abstracts of Reviews of Effects 1st Quarter 2011 EBM Reviews - Cochrane Central Register of Controlled Trials 1st Quarter 2011 EBM Reviews - Health Technology Assessment 1st Quarter 2011 EBM Reviews - NHS Economic Evaluation Database 1st Quarter 2011 Note: Duplicates between databases were removed in Ovid. |
||
Date of Search: | March 14, 2011 | ||
Alerts: | Monthly search updates began March 14, 2011 and ran until October 2011. | ||
Study Types: | Health technology assessments, systematic reviews, meta-analyses, randomized controlled trials, non-randomized studies, and diagnostic accuracy studies. | ||
Limits: | English language
Humans No date limits for systematic reviews; publication years Jan 2006 to March 2011 for primary studies. |
||
SYNTAX GUIDE | |||
/ | At the end of a phrase, searches the phrase as a subject heading | ||
MeSH | Medical subject heading | ||
.fs | Floating subheading | ||
exp | Explode a subject heading | ||
* | Before a word, indicates that the marked subject heading is a primary topic; or, after a word, a truncation symbol (wildcard) to retrieve plurals or varying endings | ||
? | Truncation symbol for one or no characters only | ||
ADJ | Requires words are adjacent to each other (in any order) | ||
ADJ# | Adjacency within # number of words (in any order) | ||
.ti | Title | ||
.ab | Abstract | ||
.hw | Heading word: usually includes subject headings and controlled vocabulary | ||
.tw | Text word: searches title, abstract, captions, and full text | ||
.mp | Keyword search: includes title, abstract, name of substance word, subject heading word and other text fields | ||
.pt | Publication type | ||
.nm | Name of substance word: used to search portions of chemical names and includes words from the CAS Registry/EC Number/Name (RN) fields | ||
.jw | Journal words: searches words from journal names | ||
/du | Diagnostic use | ||
/ri | Radionuclide imaging |
Multi-database Strategy | |
---|---|
# | Searches |
Bone tumours concept | |
1 | exp Bone Neoplasms/ |
2 | exp Neoplasms, Bone Tissue/ |
3 | Chondrosarcoma/ |
4 | Bone Marrow Neoplasms/ |
5 | ((bone or bony or skeletal* or skeleton* or spine or spines or spinal or orbital* or skull* or nose or nasal or jaw or jaws or maxillary or mandible or femoral* or femur or saccrococcygeal or sacroccyx or osseus or osteolytic or osteoblastic or osteoid) adj3 (metastatic or metastases or metastasis or neoplasm* or cancer* or tumor* or tumour* or malignanc* or carcinoma* or sarcoma*)).ti,ab. |
6 | (osteosarcoma* or osteogenic sarcoma*).ti,ab. |
7 | MBD.ti,ab. |
8 | (chondrosarcoma* or Ewing* sarcoma* or ESFT? or chordoma* or adamantinoma*).ti,ab. |
9 | (osteoma* or osteochondroma* or osteoblastoma*).ti,ab. |
10 | or/1-9 |
Radionuclide imaging concept | |
11 | Technetium/ or exp Technetium Compounds/ or exp Organotechnetium Compounds/ or exp Radiopharmaceuticals/ |
12 | Radionuclide Imaging/ |
13 | (Technetium* or Tc-99 or Tc99 or Tc-99m or Tc99m or 99mTc or 99m-Tc).ti,ab,nm. |
14 | radioisotope*.ti,ab. |
15 | ((radionucl* or nuclear or radiotracer*) adj2 (imag* or scan* or test* or diagnos*)).ti,ab. |
16 | Tomography, Emission-Computed, Single-Photon/ |
17 | (single-photon adj2 emission*).ti,ab. |
18 | (SPECT or scintigraph* or scintigram* or scintiphotograph*).ti,ab. |
19 | exp Bone Neoplasms/ri |
20 | exp "Bone and Bones"/ri |
21 | Technetium Tc 99m Medronate/ |
22 | (medronate or methyl diphosphonate).ti,ab. |
23 | ((bone or MDP) adj2 (imaging or scan*)).ti. |
24 | or/11-23 |
25 | 10 and 24 |
Filter: human studies | |
26 | exp animals/ |
27 | exp animal experimentation/ |
28 | exp models animal/ |
29 | exp animal experiment/ |
30 | nonhuman/ |
31 | exp vertebrate/ |
32 | animal.po. |
33 | or/26-32 |
34 | exp humans/ |
35 | exp human experiment/ |
36 | human.po. |
37 | or/34-36 |
38 | 33 not 37 |
39 | (comment or newspaper article or editorial or letter or note).pt. |
40 | 25 not (38 or 39) |
Filter: randomized controlled trials, non-randomized studies, diagnostic accuracy | |
41 | Randomized Controlled Trial.pt. |
42 | Controlled Clinical Trial.pt. |
43 | (Clinical Trial or Clinical Trial, Phase II or Clinical Trial, Phase III or Clinical Trial, Phase IV).pt. |
44 | Multicenter Study.pt. |
45 | (random* or sham or placebo*).ti. |
46 | ((singl* or doubl*) adj (blind* or dumm* or mask*)).ti. |
47 | ((tripl* or trebl*) adj (blind* or dumm* or mask*)).ti. |
48 | (control* adj3 (study or studies or trial*)).ti. |
49 | (non-random* or nonrandom* or quasi-random* or quasirandom*).ti. |
50 | (allocated adj "to").ti. |
51 | Cohort Studies/ |
52 | Longitudinal Studies/ |
53 | Prospective Studies/ |
54 | Follow-Up Studies/ |
55 | Retrospective Studies/ |
56 | Case-Control Studies/ |
57 | Cross-Sectional Study/ |
58 | (observational adj3 (study or studies or design or analysis or analyses)).ti. |
59 | cohort.ti. |
60 | (prospective adj7 (study or studies or design or analysis or analyses or cohort)).ti. |
61 | ((follow up or followup) adj7 (study or studies or design or analysis or analyses)).ti. |
62 | ((longitudinal or longterm or (long adj term)) adj7 (study or studies or design or analysis or analyses or data or cohort)).ti. |
63 | (retrospective adj7 (study or studies or design or analysis or analyses or cohort or data or review)).ti. |
64 | ((case adj control) or (case adj comparison) or (case adj controlled)).ti. |
65 | (case-referent adj3 (study or studies or design or analysis or analyses)).ti. |
66 | (population adj3 (study or studies or analysis or analyses)).ti. |
67 | (cross adj sectional adj7 (study or studies or design or research or analysis or analyses or survey or findings)).ti. |
68 | Comparative Study.pt. |
69 | (Validation Studies or Evaluation Studies).pt. |
70 | exp "Sensitivity and Specificity"/ |
71 | False Positive Reactions/ |
72 | False Negative Reactions/ |
73 | (sensitivit* or distinguish* or differentiat* or enhancement or identif* or detect* or diagnos* or accura* or comparison*).ti. |
74 | (predictive adj4 value*).ti,ab. |
75 | or/41-74 |
76 | 75 not case reports.pt. |
77 | 40 and 76 |
Results: primary studies | |
78 | limit 77 to english language [Limit not valid in CDSR,ACP Journal Club,DARE,CCTR,CLCMR; records were retained] |
79 | limit 78 to yr="2006 -Current" [Limit not valid in DARE; records were retained] |
80 | remove duplicates from 79 |
Filter: health technology assessments, systematic reviews, meta-analyses | |
81 | meta-analysis.pt. |
82 | meta-analysis/ or systematic review/ or meta-analysis as topic/ or exp technology assessment, biomedical/ |
83 | ((systematic* adj3 (review* or overview*)) or (methodologic* adj3 (review* or overview*))).ti,ab. |
84 | ((quantitative adj3 (review* or overview* or synthes*)) or (research adj3 (integrati* or overview*))).ti,ab. |
85 | ((integrative adj3 (review* or overview*)) or (collaborative adj3 (review* or overview*)) or (pool* adj3 analy*)).ti,ab. |
86 | (data synthes* or data extraction* or data abstraction*).ti,ab. |
87 | (handsearch* or hand search*).ti,ab. |
88 | (mantel haenszel or peto or der simonian or dersimonian or fixed effect* or latin square*).ti,ab. |
89 | (met analy* or metanaly* or health technology assessment* or HTA or HTAs).ti,ab. |
90 | (meta regression* or metaregression* or mega regression*).ti,ab. |
91 | (meta-analy* or metaanaly* or systematic review* or biomedical technology assessment* or bio-medical technology assessment*).mp,hw. |
92 | (medline or Cochrane or pubmed or medlars).ti,ab,hw. |
93 | (cochrane or health technology assessment or evidence report).jw. |
94 | (meta-analysis or systematic review).md. |
95 | or/81-94 |
96 | 40 and 95 |
Results: health technology assessments, systematic reviews, meta-analyses | |
97 | limit 96 to english language [Limit not valid in CDSR,ACP Journal Club,DARE,CCTR,CLCMR; records were retained] |
98 | remove duplicates from 97 |
OTHER DATABASES | |
---|---|
PubMed |
Same MeSH, keywords, limits, and study types used as per MEDLINE search, with appropriate syntax used. |
GREY LITERATURE SEARCHING | |
---|---|
Dates for Search: | March 10 to 18, 2011 |
Keywords: | Included terms for bone cancer, bone tumours, and diagnostic imaging |
Limits: | Focus on publication years 2005 to present. |
The following sections of the CADTH grey literature checklist, "Grey matters: a practical search tool for evidence-based medicine" (http://www.cadth.ca/grey-matters), were searched:
The American College of Radiology (ACR) uses a modified Delphi process to reach its appropriateness criteria. ACR authors first review relevant information and create a summary. This summary is reviewed by clinicians and other medical professionals. The process allows for the incorporation of expert consensus when published evidence is lacking. A panel of experts rates the information to determine appropriateness of the imaging intervention.
Appropriateness is rated between 1 and 9 and is grouped into three categories: "usually not appropriate" (scores of 1, 2, and 3) or as not indicated in a certain clinical setting and unlikely to have a favourable risk-benefit ratio for patients; "maybe appropriate" (scores of 4, 5, and 6) or as potentially indicated in certain clinical settings and having potential to have an equivocal risk-benefit for patients; and "usually appropriate" (scores of 7, 8, and 9) or as indicated in certain clinical settings and having a favourable risk-benefit ratio for patients. All ratings are based on peer-reviewed literature and the opinions of the expert panel. The expert panel must reach consensus (defined as 80% agreement) after three rounds of scoring before the ACR appropriateness scores are finalized.
Breast Cancer | |
Type: Stage I carcinoma — initial presentation is asymptomatic | |
Modality | Rating and comments |
99mTc bone scan — whole body | Rating = 1 ("usually not appropriate") |
Myelography and post-myelography CT spine | Rating = 1 ("usually not appropriate") |
MRI with or without contrast — area of interest | Rating = 1 ("usually not appropriate") |
18FDG-PET scan — whole body | Rating = 1 ("usually not appropriate") |
Type: Stage I carcinoma — purpose is to rule out bone metastases | |
Modality | Rating and comments |
99mTc bone scan — whole body | Rating = 2 ("usually not appropriate") |
18FDG-PET scan — whole body | Rating = 2 ("usually not appropriate") |
Type: Stage II carcinoma — presenting with back and hip pain | |
Modality | Rating and comments |
99mTc bone scan — whole body | Rating = 9 ("usually appropriate") |
99mTc bone scan (with SPECT) — hip and spine | Rating = 1 ("usually not appropriate") |
Myelography and post-myelography CT spine | Rating = 1 ("usually not appropriate") |
CT (with or without contrast) — hip and spine | Rating = 1 ("usually not appropriate") |
MRI (with or without contrast) — hip and spine | Rating = 1 ("usually not appropriate") |
18FDG-PET scan — whole body | Rating = 5 ("may be appropriate") |
Type: Known bone metastatic disease — presenting with pathological fracture of left femur on x-ray | |
Modality | Rating and comments |
99mTc bone scan — whole body | Rating = 9 ("usually appropriate") |
18FDG-PET scan — whole body | Rating = 5 ("may be appropriate"); if bone scan is negative, findings on PET will influence the use of systemic treatment. |
CT without contrast — femur | Rating = 1 ("usually not appropriate") |
MRI without contrast — femur | Rating = 1 ("usually not appropriate") |
Prostate Cancer | |
Type: Nodule on physical exam; moderately or well-differentiated carcinoma; PSA < 20mg/mL; asymptomatic patients | |
Modality | Rating and comments |
99mTc bone scan — whole body | Rating = 1 ("usually not appropriate") |
CT with or without contrast — area of interest | Rating = 1 ("usually not appropriate") |
MRI with or without contrast — area of interest | Rating = 1 ("usually not appropriate") |
18FDG-PET scan — whole body | Rating = 1 ("usually not appropriate") |
Type: Nodule on physical exam; poorly differentiated carcinoma; PSA ³ 20mg/mL; asymptomatic patients | |
Modality | Rating and comments |
99mTc bone scan — whole body | Rating = 9 ("usually appropriate") |
CT with or without contrast — area of interest | Rating = 1 ("usually not appropriate") |
MRI with or without contrast — area of interest | Rating = 1 ("usually not appropriate") |
18FDG-PET scan — whole body | Rating = 1 ("usually not appropriate") |
Lung Cancer | |
Type: 1 cm lung nodule; NSCLC at needle biopsy — presenting for staging and resection | |
Modality | Rating and comments |
99mTc bone scan — whole body | Rating = 9 ("usually appropriate"); not needed if a PET scan is performed for initial nodule workup. |
18FDG-PET scan — whole body | Rating = 9 ("usually appropriate") |
CT without contrast — chest | Rating = 1 ("usually not appropriate") |
MRI without contrast — chest | Rating = 1 ("usually not appropriate") |
Type: Non-invasive staging of NSCLC | |
Modality | Rating and comments |
99mTc bone scan — whole body | Rating = 5 ("may be appropriate"); not needed if a PET scan has been performed |
18FDG-PET scan — skull base to mid-thigh | Rating = 9 ("usually appropriate"); attenuation correction by radionuclide or CT |
CT with or without contrast — chest | Rating = 9 ("usually appropriate"); contrast is preferred if not contraindicated |
CT with contrast —abdomen | Rating = 5 ("may be appropriate"); contrast is preferred if not contraindicated |
CT with contrast — head | Rating = 5 ("may be appropriate"); used if MRI is contraindicated and the patient has neurological symptoms |
MRI with or without contrast — head | Rating = 7 ("usually appropriate"); if the patient has neurological symptoms; or if the patient is asymptomatic, but the tumour is > 3 cm and has adenocarcinoma histology or mediastinal adenopathy |
MRI with or without contrast — chest | Rating = 3 ("usually appropriate"); evaluating chest wall or cardiac invasion and for local staging of superior sulcus tumours. |
CT = computed tomography; 18FDG = 18F-fluorodeoxyglucose; MRI = magnetic resonance imaging; NSCLC = non–small cell lung cancer; PET = positron emission tomography; PSA = prostate-specific antigen; SPECT = single-photon emission computed tomography; 99mTc = technetium-99m.
Study | Objective | Population | Intervention and Comparator | Study Design | Location |
---|---|---|---|---|---|
Breast Cancer | |||||
Morris et al. 201011 | To compare the diagnostic performance of BS and PET/CT in women with suspected metastatic breast cancer | All women undergoing evaluation of suspected metastatic breast cancer between 2003 and 2008
Excluded patients with a previous history of metastatic breast cancer or active secondary malignancy |
Intervention: whole body bone scan with 99mTc-MDP
Comparator: PET/CT from mid-skull to upper thighs |
Retrospective cohort | Single centre in the United States |
Port et al. 200612 | To determine the utility of FDG-PET compared with conventional imaging in evaluating the extent of disease in patients with high-risk, operable breast cancer | Patients who presented for operative treatment of breast cancer between 2001 and 2004 who had high-risk disease, defined as:
Tumour size > 5 cm (T3) and/or clinically positive lymph nodes (N1/2) |
Intervention: whole body bone scan with 99mTc-MDP and CT of the chest, abdomen, and pelvis (conventional imaging)
Comparator: FDG-PET |
Prospective cohort | Single centre in the United States |
Lung Cancer | |||||
Nosotti et al. 200813 | To compare preoperative staging using PET and conventional imaging technologies | Patients with proven or strongly suspected lung cancer referred to a thoracic surgery unit between 1999 and 2004
Proven NSCLC, pulmonary mass positive to PET, no history of previous cancer, no history of severe diabetes mellitus |
Intervention: bone scan (radiopharmaceutical not identified)
Comparator: whole body FDG-PET |
Prospective cohort | Single centre in Italy |
Fischer et al. 200714 | To examine PET/CT compared with conventional staging in patients with SCLC | Patients older than 18 years with histological or cytological proven SCLC were enrolled between 2003 and 2004
Patients with type 1 diabetes mellitus, known former or current malignancy other than SCLC, claustrophobia, pregnancy |
Intervention: whole body bone scan with 99mTc oxydronate, bone marrow analysis, and CT scan
Comparator: PET/CT (FDG-PET) from head to upper thigh |
Prospective cohort | Denmark
Number of centres not reported |
Prostate | |||||
Meirelles et al. 201015 | To evaluate BS and FDG-PET in patients with progressing metastatic prostate cancer | Patients with progressive prostate cancer who were enrolled in a prospective study between 1997 and 2000
Included those with at least 5 years of follow-up with histologically proven adenocarcinoma of the prostate and progression of disease as indicated from increasing PSA and an abnormality on imaging with BS, CT, or MRI that was consistent with bone metastases |
Intervention: bone scan with 99mTc-MDP
Comparator: whole-body FDG-PET |
Prospective | United States
Number of centres not reported |
BS = bone scan; CT = computed tomography; 18FDG =18F fluorodeoxyglucose; MRI = magnetic resonance imaging; NSCLC = non–small cell lung cancer; NS = no studies; PSA = prostate specific antigen; PET = positron emission tomography; SCLC = small cell lung cancer; T = tesla; 99mTc = technetium-99m; 99mTc-MDP = technetium-99m–labelled methylene diphosphonate.
Study | Patient Characteristics | Diagnostic Accuracy | Conclusions | Limitations |
---|---|---|---|---|
Breast Cancer | ||||
Morris et al. 201011 | N = 163
Suspicious symptoms: 84% Stages I to III breast cancer diagnosed > 12 weeks prior to imaging: 58% Estrogen receptor positive: 55% Progesterone receptor positive: 41% HER2 positive: 24% |
Concordance between BS and 18FDG-PET/CT: 81% (132 of 163 studies)
For the 31 patients with discordant findings: 18 had positive 18FDG-PET/CT and negative BS 2 had negative 18FDG-PET/CT and positive BS The remaining 11 patients had equivocal findings on one of the imaging techniques |
There is a high degree of concordance between imaging techniques, suggesting that they could be redundant.
18FDG-PET/CT may be superior to BS for detecting metastases in patients with breast cancer. |
Only patients who underwent both imaging modalities were included, which could limit the generalizability of the findings.
18FDG-PET/CT was reserved for patients with diagnostic uncertainty, which could also affect the generalizability of the findings. No analysis according to stage Sensitivity and specificity were not computed. Single-centre study Authors stated that their sample reflected a subgroup of patients with breast cancer. |
Port et al. 200612 | N = 80
Histological characteristics: Ductal: 78.8% Lobular: 7.5% Unknown/other: 13.8% Clinical stage at presentation: IIB: 50% Occult primary: 8.8% IIIA: 26.2% Locoregional recurrence: 15.0% Node status: Positive: 83.6% Negative: 16.4% |
Sensitivity:
Conventional imaging — 80% 18FDG-PET — 80% Specificity: Conventional imaging — 79% 18FDG-PET — 94% |
The use of PET for determining the extent of disease in patients with breast cancer may be appropriate in selected patients at high risk for having relevant findings. | BS was in combination with CT
No analysis according to stage Did not report whether patients were symptomatic Some scans were performed at outside facilities, not the study centre Single staff radiologist interpreted the images, which could affect generalizability. Single-centre study Did not report results according to stage of cancer. |
Lung Cancer | ||||
Nosotti et al. 200813 | N = 413
Adenocarcinoma — 64.8% Squamous cell carcinoma: 30.2% Large cell carcinoma: 5% |
Sensitivity:
BS — 67% 18 FDG-PET — 96% Specificity: BS — 94% 18 FDG-PET — 99% PPV: BS — 64% 18 FDG-PET — 98% NPV: BS — 95% 18 FDG-PET — 99% |
PET imaging strategy is more accurate than conventional imaging for the detection of metastases. | Few patient characteristics reported.
Unclear if patients were symptomatic or asymptomatic Single-centre study No information on the radiopharmaceutical used for the bone scan. No information about image interpretation or blinding of the individual(s) interpreting images was reported. Did not report results according to stage of cancer. |
Fischer et al. 200714 | N = 29
Final stage: Limited disease — 24% Extensive disease — 59% Undetermined — 18% |
Sensitivity for bone metastases:
BS — 75% 18FDG-PET/CT — 80% Specificity for bone metastases: BS — 58% 18FDG-PET/CT — not reported 18FDG-PET/CT suggested a different stage than conventional staging in 17% of patients (n = 5) |
There is most likely a role for 18FDG-PET/CT in the staging of SCLC, but larger trials are needed before conclusions can be made. | Few patient characteristics reported.
Unclear if patients were symptomatic or asymptomatic Specificity of 18FDG-PET/CT for bone metastases not reported Sample size of 29 patients Unclear how patients were selected for inclusion (i.e., if all patients who reported for staging during the study period were included or whether the study involved a selected population). Did not report results according to stage of cancer. |
Prostate | ||||
Meirelles et al. 201015 | N = 51
Castrate-resistant disease: 76% No other characteristics reported |
BS detected bone metastases in significantly (P = 0.01) more patients than 18FDG-PET.
Detection of metastases: BS: 86.1% 18FDG-PET: 72.1% Discordance between techniques: 18FDG-PET positive, BS negative: 0% 18FDG-PET negative, BS positive: 14% |
In patients with progressing prostate cancer, bone metastases are readily identifiable on 18FDG-PET. | Unclear if the same radiologist and nuclear medicine physician interpreted all images.
Did not report sensitivity and specificity. Limited patient characteristics reported. Did not report results according to stage of cancer. High risk patients — could potentially limit generalizability to other patients with prostate cancer. |
BS = bone scan; CT = computed tomography; 18FDG =18F fluorodeoxyglucose; HER2 = Human Epidermal Growth Factor Receptor 2; MRI = magnetic resonance imaging; NPV = negative predictive value; NSCLC = non–small cell lung cancer; NS = no studies; PET = positron emission tomography; PPV = positive predictive value; PSA = prostate specific antigen; SCLC = small cell lung cancer.