FDG-PET for detection of osseous metastases from malignant primary bone tumours: comparison with bone scintigraphy

The purpose of this study was to compare positron emission tomography using fluorine-18 fluorodeoxyglucose (FDG-PET) and technetium-99m methylene diphosphonate (MDP) bone scintigraphy in the detection of osseous metastases from malignant primary osseous tumours. In 70 patients with histologically proven malignant primary bone tumours (32 osteosarcomas, 38 Ewing's sarcomas), 118 FDG-PET examinations were evaluated. FDG-PET scans were analysed with regard to osseous metastases in comparison with bone scintigraphy. The reference methods for both imaging modalities were histopathological analysis, morphological imaging [additional conventional radiography, computed tomography (CT) or magnetic resonance imaging (MRI)] and/or clinical follow-up over 6-64 months (median 20 months). In 21 examinations (18%) reference methods revealed 54 osseous metastases (49 from Ewing's sarcomas, five from osteosarcomas). FDG-PET had a sensitivity of 0.90, a specificity of 0.96 and an accuracy of 0.95 on an examination-based analysis. Comparable values for bone scintigraphy were 0.71, 0.92 and 0.88. On a lesion-based analysis the sensitivity of FDG-PET and bone scintigraphy was 0.80 and 0.72, respectively. Analysing only Ewing's sarcoma patients, the sensitivity, specificity and accuracy of FDG-PET and bone scan were 1.00, 0.96 and 0.97 and 0.68, 0.87 and 0.82, respectively (examination-based analysis). None of the five osseous metastases from osteosarcoma were detected by FDG-PET, but all of them were true-positive using bone scintigraphy. In conclusion, the sensitivity, specificity and accuracy of FDG-PET in the detection of osseous metastases from Ewing's sarcomas are superior to those of bone scintigraphy. However, in the detection of osseous metastases from osteosarcoma, FDG-PET seems to be less sensitive than bone scintigraphy.     

FDG-PET for detection of osseous metastases from malignant primary bone tumours: comparison with bone scintigraphy

The purpose of this study was to compare positron emission tomography using fluorine-18 fluorodeoxyglucose (FDG-PET) and technetium-99m methylene diphosphonate (MDP) bone scintigraphy in the detection of osseous metastases from malignant primary osseous tumours. In 70 patients with histologically proven malignant primary bone tumours (32 osteosarcomas, 38 Ewing's sarcomas), 118 FDG-PET examinations were evaluated. FDG-PET scans were analysed with regard to osseous metastases in comparison with bone scintigraphy. The reference methods for both imaging modalities were histopathological analysis, morphological imaging [additional conventional radiography, computed tomography (CT) or magnetic resonance imaging (MRI)] and/or clinical follow-up over 6-64 months (median 20 months). In 21 examinations (18%) reference methods revealed 54 osseous metastases (49 from Ewing's sarcomas, five from osteosarcomas). FDG-PET had a sensitivity of 0.90, a specificity of 0.96 and an accuracy of 0.95 on an examination-based analysis. Comparable values for bone scintigraphy were 0.71, 0.92 and 0.88. On a lesion-based analysis the sensitivity of FDG-PET and bone scintigraphy was 0.80 and 0.72, respectively. Analysing only Ewing's sarcoma patients, the sensitivity, specificity and accuracy of FDG-PET and bone scan were 1.00, 0.96 and 0.97 and 0.68, 0.87 and 0.82, respectively (examination-based analysis). None of the five osseous metastases from osteosarcoma were detected by FDG-PET, but all of them were true-positive using bone scintigraphy. In conclusion, the sensitivity, specificity and accuracy of FDG-PET in the detection of osseous metastases from Ewing's sarcomas are superior to those of bone scintigraphy. However, in the detection of osseous metastases from osteosarcoma, FDG-PET seems to be less sensitive than bone scintigraphy.     

Comparison of Tc-99m-labelled antileukocyte fragment Fab' and Tc-99m-HMPAO leukocyte scintigraphy in the diagnosis of bone and joint infections: a prospective study

Between January and July 1998, we conducted a prospective study to compare Tc-99m-labelled antigranulocyte monoclonal antibody fragment Fab' (LEUKOSCAN) scintigraphy versus Tc-99m-hexamethylpropyleneamine oxime (Tc-99m-HMPAO)-labelled leukocyte scintigraphy (HMPAO-LS) for the diagnosis of unselected patients with bone and joint infection. Twenty-three patients (16 men and 7 women; mean age, 67 years) with suspected bone infection were explored successively with bone scintigraphy, HMPAO-LS and LEUKOSCAN scintigraphy. Thirty-two foci were studied (diabetic foot = 11, prosthetic material = 8, joint disease = 4, others = diagnosed in 18 cases, eight on the basis of bacteriological and histological examination of surgical or puncture specimens, with or without radiographic signs, and 10 on the basis of clinical course and radiographic findings. Overall sensitivity, specificity and accuracy were 86%, 72% and 78%, respectively, for LEUKOSCAN scintigraphy (12 true positives (TP), 13 true negatives (TN), 5 false positives (FP), 2 false negatives (FN)), 93%, 100% and 96%, respectively, for HMPAO-LS (13TP, 18TN, 0FP, 1FN), and 100%, 17% and 53.3%, respectively, for bone scintigraphy. In this small series, LEUKOSCAN scintigraphy was found to be less specific for the diagnosis of osteomyelitis than HMPAO-LS. In addition, the interpretation of LEUKOSCAN scintigraphy is more difficult than HMPAO-LS for the diagnosis of bone infection in the diabetic foot, and would appear to be less discriminating for differentiating soft tissue infection from osteitis in the case of plantar perforating ulcers.     

Bone metastases in carcinoid tumors: clinical features, imaging characteristics, and markers of bone metabolism.

The purpose of this study was to describe the clinical presentation of bone metastases in patients with carcinoid tumors and to determine the diagnostic value of imaging techniques and markers of bone metabolism. METHODS: This retrospective study was performed on the entire group of patients with carcinoid tumors treated in our hospital from January 1992 to May 1999. Only patients with metastasized tumors were included. RESULTS: Eleven of 90 patients (12%) (95% confidence interval [CI], 5%-19%) with a metastasized carcinoid tumor had symptomatic bone metastases. All bone metastases occurred in 55 patients with midgut carcinoids (20%; 95% CI, 9%-31%). Plain radiography had a sensitivity of 44% (95% CI, 12%-76%); MRI, 100% (95% CI, 61%-100%); bone scintigraphy, 90% (95% CI, 72%-100%); and octreotide scintigraphy, 60% (95% CI, 35%-93%). In 9 patients, both octreotide scintigraphy and bone scintigraphy were performed. Of 45 bone lesions, 22 (49%) were visualized by both modalities, 13 (29%) were visualized with octreotide scintigraphy but not with bone scintigraphy, and 10 (22%) were visualized with bone scintigraphy but not with octreotide scintigraphy. In 2 patients, octreotide scintigraphy and bone scintigraphy provided complementary results. Markers of bone metabolism could not discriminate carcinoid patients from those without bone metastases. The markers of bone metabolism did not reflect the osteolytic or osteoblastic appearance of metastases. CONCLUSION: Pain is the principal symptom of bone metastases in patients with carcinoid tumors. Plain radiography and markers of bone metabolism do not contribute to the diagnosis of bone metastases. MRI has a high sensitivity for bone metastases. Both bone scintigraphy and octreotide scintigraphy have acceptable sensitivity and can provide complementary results.     

Leukoscan for orthopaedic imaging in clinical practice

Studies have suggested that orthopaedic infection can be successfully imaged with 99mTc antigranulocyte antibody Fab' fragments (Leukoscan). This study examined the value of the technique in a UK clinical practice. A retrospective review of the first 55 patients imaged was performed. Patients had three-phase bone scintigraphy followed by Leukoscan imaging. The latter was performed using planar views 2 h and 6 h post-injection of 750 MBq 99mTc Leukoscan. In 47 patients there was adequate clinical information available to compare to the scintigraphy result. There were 13 positive infections. The Leukoscan findings produced 11 true positives, 26 true negatives, eight false positives and two false negatives with resulting sensitivity 85%, specificity 77%, positive predictive accuracy 58%, and negative predictive accuracy 93%. This study suggests that Leukoscan can be used successfully to image orthopaedic infection, with its greatest strength being a high negative predictive accuracy. Positive studies may require further correlative imaging.     

18F-FDG PET or PET/CT for detection of metastatic lymph nodes in patients with endometrial cancer: A systematic review and meta-analysis

The present study assessed the diagnostic performances of 18F-FDG PET or PET/CT in detecting pelvic and/or paraaortic lymph node metastasis in patients with endometrial cancer. METHODS: Through a search of MEDLINE (January 1998 to March 2011), an overall weighted average for sensitivity and specificity as well as pooled estimates of positive and negative likelihood ratios were calculated. A summary receiver-operating-characteristics (sROC) curve was constructed and the area under the sROC curve (AUC) was calculated. I-square was calculated to explore heterogeneity. RESULTS: The present study included 243 patients from seven studies. Results indicated a lack of significant heterogeneity for sensitivity and specificity (I(2)<50% and p>0.05). The overall pooled estimates for sensitivity and specificity of FDG-PET or PET/CT scans in the detection of pelvic and/or paraaortic metastasis were 63.0% (95% CI, 48.7-75.7%) and 94.7% (95% CI, 90.4-97.4%), respectively. The positive likelihood ratio was 10.465 (95% CI, 5.646-19.396) and the negative likelihood ratio 0.399 (95% CI, 0.284-0.560). The AUC was 0.9533. The overall diagnostic accuracy (Q* index) was 89.5%. Conclusion The high positive likelihood value confirms the reliability of a positive FDG-PET or PET/CT to detect pelvic and/or paraaortic lymph nodes metastasis in patients with untreated endometrial cancer. FDG-PET or PET/CT may prove beneficial to surgeons when selecting appropriate patients on whom to perform lymphadenectomy.     

Comparison of18FDG-PET with99mTc-HMDP scntigraphy for the detection of bone metastases in patients with breast cancer

OBJECTIVE: Bone is one of the most common sites of metastasis in breast cancer patients. Although bone scintigraphy is widely used to detect metastatic breast cancer, the usefulness of 18FDG-PET for detecting bone metastasis has not been clearly evaluated. The purpose of this study was to compare the diagnostic accuracy of 18FDG-PET with bone scintigraphy in detecting bone metastasis in breast cancer patients. METHODS: Forty-four women aged 35 to 81 years (mean, 56 years) with breast cancer were examined in this study. Both 18FDG-PET and bone scintigraphy were performed for each patient with 0-69 day intervals (mean, 11.5 days). The results of each image interpretation were compared retrospectively. Whole-body bones were classified into 9 anatomical regions. Metastases were confirmed at 45/187 regions in 14 patients by bone biopsy or clinical follow-up including other imaging techniques for a period of at least 6 months afterwards. RESULTS: On a region basis, the sensitivity, specificity, and accuracy of 18FDG-PET were 84%, 99% and 95%, respectively. Although these results were comparable to those of bone scintigraphy, the combination of 18FDG-PET and bone scintigraphy improved the sensitivity (98%) and accuracy (97%) of detection. False negative lesions of bone scintigraphy were mostly bone marrow metastases and those of 18FDG-PET were mostly osteoblastic metastases. 18FDG-PET was superior to bone scintigraphy in the detection of osteolytic lesions (92% vs. 73%), but inferior in the detection of osteoblastic lesions (74% vs. 95%). CONCLUSIONS: This study shows that 18FDG-PET tends to be superior to bone scintigraphy in the detection of osteolytic lesions, but inferior in the detection of osteoblastic lesions. 18FDG-PET should play a complementary role in detecting bone metastasis with bone scintigraphy.     

FDG-PET, 99mtc-HMPAO white blood cell SPET and bone scintigraphy in the evaluation of painful total knee arthroplasties.

Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET), technetium-99m hexamethylpropylene amine oxime (HMPAO)-labelled white blood cell (WBC) scintigraphy and bone scintigraphy were used in the evaluation of total knee arthroplasties (TKAs). We prospectively included 21 patients who had a three-phase bone scan for exclusion of infection of TKAs. Four hours after injection of 185 MBq 99mTc-HMPAO-labelled WBCs, planar and single-photon emission tomographic (SPET) imaging was performed. Planar imaging was repeated at 24 h p.i. Consecutively images of the knees were obtained with a dedicated PET system 60 min following the injection of 370 MBq of FDG. Focal tracer uptake was scored on SPET and PET visually (0=no uptake, 4=intense uptake). In addition, SUV (standardised uptake value) per voxel was calculated from attenuation-corrected PET images using the MLAA algorithm. Focal uptake at the bone-prosthesis interface was used as the criterion for infection before and after correlation with the third phase of the bone scan. Final diagnosis was based on operative findings, culture and clinical outcome. In the infected TKAs, the WBC scan showed focal activity of grade 2 (n=2), 3 (n=l) or 4 (n=2). PET scan revealed focal activity of grade 4 (n=5) or 3 (n=1). WBC scan alone had a specificity for infection of 53% [positive predictive value (PPV) 42%, sensitivity 100%], compared with 73% for PET scan (PPV 60%, sensitivity 100%). Considering only lesions at the bone-prosthesis interface that were also present on the third phase of the bone scan, we found a specificity of 93% (PPV 83%) for WBC scan. Using these criteria, a specificity of 80% (PPV 67%) was obtained for PET scan. Two out of three false-positive PET scans were due to loosening of the TKA. It is concluded that WBC scintigraphy in combination with bone scintigraphy has a high specificity in the detection of infected TKAs. FDG-PET seems to offer no additional benefit.     

FDG-PET, 99mTc-HMPAO white blood cell SPET and bone scintigraphy in the evaluation of painful total knee arthroplasties

Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET), technetium-99m hexamethylpropylene amine oxime (HMPAO)-labelled white blood cell (WBC) scintigraphy and bone scintigraphy were used in the evaluation of total knee arthroplasties (TKAs). We prospectively included 21 patients who had a three-phase bone scan for exclusion of infection of TKAs. Four hours after injection of 185 MBq ^99mTc-HMPAO-labelled WBCs, planar and single-photon emission tomographic (SPET) imaging was performed. Planar imaging was repeated at 24 h p.i. Consecutively images of the knees were obtained with a dedicated PET system 60 min following the injection of 370 MBq of FDG. Focal tracer uptake was scored on SPET and PET visually (0=no uptake, 4=intense uptake). In addition, SUV (standardised uptake value) per voxel was calculated from attenuation-corrected PET images using the MLAA algorithm. Focal uptake at the bone-prosthesis interface was used as the criterion for infection before and after correlation with the third phase of the bone scan. Final diagnosis was based on operative findings, culture and clinical outcome. In the infected TKAs, the WBC scan showed focal activity of grade 2 (n=2), 3 (n=1) or 4 (n=2). PET scan revealed focal activity of grade 4 (n=5) or 3 (n=1). WBC scan alone had a specificity for infection of 53% [positive predictive value (PPV) 42%, sensitivity 100%], compared with 73% for PET scan (PPV 60%, sensitivity 100%). Considering only lesions at the bone-prosthesis interface that were also present on the third phase of the bone scan, we found a specificity of 93% (PPV 83%) for WBC scan. Using these criteria, a specificity of 80% (PPV 67%) was obtained for PET scan. Two out of three false-positive PET scans were due to loosening of the TKA. It is concluded that WBC scintigraphy in combination with bone scintigraphy has a high specificity in the detection of infected TKAs. FDG-PET seems to offer no additional benefit.     

Imaging of infected total arthroplasty with Tc-99m-labeled antigranulocyte antibody Fab'fragments

OBJECTIVE: The objective of this study was to evaluate the diagnostic accuracy of Tc-99m-labeled antigranulocyte antibody Fab' fragments in infected total arthroplasty. MATERIALS AND METHODS: A total of 38 immunoscintigrams were evaluated retrospectively with 15 to 25 mCi Tc-99m-labeled antigranulocyte antibody-Fab' fragments. The final diagnosis was assessed by articular puncture or intraoperative sampling. RESULTS: In the total hip replacement group the authors found 10 true positives, 7 true negatives, 8 false positives, and 1 false negative; and in the total knee replacement group they found 4 true positives, 8 true negatives, and no false positives or false negatives. They also found a sensitivity of 93%, a specificity of 65%, and a positive predictive accuracy of 63%. There was a negative predictive accuracy of 94%. CONCLUSION: The high negative predictive accuracy in the whole group suggests that the scan can be used to exclude infection in most cases. Negative results with a high clinical suspicion merits further investigation. A positive result will require further correlative imaging, especially for total knee replacement.     

Staging and monitoring of malignant lymphoma of the bone: comparison of 67Ga scintigraphy and MRI.

The aim of this study was two-fold: to compare 67Ga scintigraphy with MRI (a) for the staging of malignant lymphoma of the bone and (b) with regard to accuracy in detecting residual disease after first-line chemotherapy for restaging. METHODS: Twenty-one patients with 36 malignant osseous lesions were examined, including 7 patients with primary or multifocal osseous lymphoma and 14 patients with malignant lymphoma and simultaneous or secondary involvement of the bone. After first-line therapy, MRI and 67Ga scintigraphy were performed on 13 patients. The remission status based on all clinical and radiological findings during the follow-up was used as the gold standard. RESULTS: The osseous lesions were located on the axial skeleton in 64% of patients and on the appendicular skeleton in 36%. 67Ga scintigraphy detected 77% of the osseous lesions examined by MRI. For restaging after first-line therapy, MRI had a sensitivity of 90% and a specificity of 80% when dynamic MRI information was included. There were several false-positive results as a result of the pathologic increase in signal intensity ratios of reactive hematopoietic regions after chemotherapy. For 67Ga scintigraphy, a sensitivity of 70% and a specificity of 93% were calculated. CONCLUSION: These data show that monitoring malignant lymphoma of the bone still presents diagnostic problems. Given the high sensitivity of MRI and the high specificity of 67Ga scintigraphy but the limited specificity of MRI and sensitivity of 67Ga scintigraphy, both methods are valuable but should be used as complementary diagnostic tools.     

Diagnostic accuracy of bone scintigraphy in the assessment of cardiac transthyretin-related amyloidosis: a bivariate meta-analysis

Purpose

Cardiac transthyretin-related amyloidosis (ATTR) is a progressive and fatal cardiomyopathy. The diagnosis of this disease is frequently delayed or missed due to the limited specificity of echocardiography. An increasing amount of data in the literature demonstrate the ability of bone scintigraphy with bone-seeking radiopharmaceuticals to detect myocardial amyloid deposits, in particular in patients with ATTR. Therefore we performed a systematic review and bivariate meta-analysis of the diagnostic accuracy of bone scintigraphy in patients with suspected cardiac ATTR.

Methods

A comprehensive computer literature search of studies published up to 30 November 2017 on the role of bone scintigraphy in patients with ATTR was performed using the following search algorithm: (a) “amyloid” OR “amyloidosis” AND (b) “TTR” OR “ATTR” OR “transthyretin” AND (c) “scintigraphy” OR “scan” OR “SPECT” OR “SPET” OR “bone” OR “skeletal” OR “skeleton” OR “PYP” OR “DPD” OR “HMDP” OR “MDP” OR “HDP”. Pooled sensitivity, specificity, positive and negative likelihood ratios (LR+ and LR?) and diagnostic odds ratio (DOR) of bone scintigraphy were calculated.

Results

The meta-analysis of six selected studies on bone scintigraphy in cardiac ATTR including 529 patients provided the following results: sensitivity 92.2% (95% CI 89–95%), specificity 95.4% (95% CI 77–99%), LR+ 7.02 (95% CI 3.42–14.4), LR? 0.09 (95% CI 0.06–0.14), and DOR 81.6 (95% CI 44–153). Mild heterogeneity was found among the selected studies.

Conclusion

Our evidence-based data demonstrate that bone scintigraphy using technetium-labelled radiotracers provides very high diagnostic accuracy in the non-invasive assessment of cardiac ATTR.

     

Fever of unknown origin: prospective comparison of diagnostic value of <Superscript>18</Superscript>F-FDG PET and <Superscript>111</Superscript>In-granulocyte scintigraphy

The diagnostic work-up in patients with fever of unknown origin (FUO) is often challenging and frequently includes nuclear medicine procedures. Whereas a role for leucocyte or granulocyte scintigraphy in FUO is generally accepted, a possible role of fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in these patients remains to be established. To study this, we compared prospectively, on a head-to-head basis, the diagnostic value of FDG-PET and indium-111 granulocyte scintigraphy in patients with FUO. Nineteen patients with FUO underwent both FDG-PET and ¹¹¹In-granulocyte scintigraphy within 1 week. FDG-PET scans and granulocyte scintigrams were reviewed by different doctors who were blinded to the result of the other investigation. The diagnostic values of FDG-PET and granulocyte scintigraphy were evaluated with regard to identification of a focal infectious/inflammatory or malignant cause of FUO. The sensitivity of granulocyte scintigraphy and FDG-PET were 71% [95% confidence interval (CI): 37–85%] and 50% (CI: 16–84%), respectively. The specificity of granulocyte scintigraphy was 92% (71–100%), which was significantly higher than that of FDG-PET, at 46% (34–62%). Positive and negative predictive values for granulocyte scintigraphy were both 85%. Positive and negative predictive values for FDG-PET were 30% and 67%, respectively. ¹¹¹In-granulocyte scintigraphy has a superior diagnostic performance compared to FDG-PET for detection of a localised infectious/inflammatory or neoplastic cause of FUO. The poorer performance of FDG-PET is in particular attributable to a high percentage of false positive scans, leading to low specificity.     

Utility of<Superscript>99m</Superscript>Tc dextran scintigraphy in diabetic patients with suspected osteomyelitis of the foot

PURPOSE: Osteomyelitis of the foot is a frequent complication of diabetes mellitus and its diagnosis is often difficult. The goal of this study was to demonstrate the utility of 99mTc dextran scintigraphy in suspected diabetic foot infections. MATERIALS AND METHODS: Twenty-six patients (20 males, 6 females, age range 18-80 years) with diabetes mellitus who had a total of 36 foot ulcers or necrosis were studied. All the patients underwent both three phase bone scan and 99mTc dextran scintigraphy. Final diagnosis was based upon either pathologic examination or clinical follow-up at least four months. RESULTS: On bone scan increased uptake was seen in 55 sites, and among these there were 11 lesions of proven osteomyelitis. There were 11 true-positive, 0 false negative, 0 true negative and 44 false positive results for bone scan. The sensitivity, specificity and accuracy of bone scan were 100%, 0% and 20%, respectively. With regard to 99mTc dextran scan, nine lesions produced true-positive results with two lesions indicating false negatives resulting in a sensitivity of 82%. Thirty-six true negative and eight false positive results produced a specificity of 82%, and an accuracy 82% from 99mTc dextran studies was obtained. Eight false-positive results were possibly due to neuroarthropathy, pressure points and deep penetrating ulcers. A patient with one false-negative result had angiopathy while other had neither neuropathy nor angiopathy. CONCLUSIONS: According to these results, 99mTc dextran scintigraphy seems to be a sensitive and specific diagnostic method, and because of its advantages over other radiopharmaceuticals (shorter preparation time, highly stability in vivo/in vitro, early diagnostic imaging and low cost), it may be a radiopharmaceutical of choice for diagnosing in diabetic foot infections.     

A meta-analysis of ¹⁸FDG-PET-CT, ¹⁸FDG-PET, MRI and bone scintigraphy for diagnosis of bone metastases in patients with lung cancer

Background and purpose

Lung cancer is the most common cause of cancer related death among both men and women worldwide. The skeleton is the most common site of cancer metastasis. Early detection is crucial for prognosis. To evaluate and compare the capability for bone metastasis assessment of [¹⁸F] fluoro-2-d-glucose positron emission tomography with computed tomography (¹⁸FDG-PET–CT), [¹⁸F] fluoro-2-d-glucose positron emission tomography (¹⁸FDG-PET), magnetic resonance imaging (MRI) and bone scintigraphy (BS) in lung cancer patients, a meta-analysis is preformed.

Methods

We searched MEDLINE, OVID, EMBASE and the Cochrane Library for studies evaluating diagnosis validity of ¹⁸FDG-PET–CT, ¹⁸FDG-PET, MRI and BS between January 1990 and August 2010. Meta-analysis methods were used to pool sensitivity, specificity, diagnostic odd ratios (DORs) and to construct a summary receiver-operating characteristic curve (SROC).

Results

A total of 17 articles (9 ¹⁸FDG-PET–CT studies, 9 ¹⁸FDG-PET studies, 6 MRI studies and 16 BS studies) that included 2940 patients who fulfilled all of the inclusion criteria were considered for inclusion in the analysis. The pooled sensitivity for the detection of bone metastasis in lung cancer using ¹⁸FDG-PET–CT, ¹⁸FDG-PET, MRI and BS were 0.92 (95% CI, 0.88–0.95), 0.87 (95% CI, 0.81–0.92), 0.77 (95% CI, 0.65–0.87) and 0.86 (95% CI, 0.82–0.89), respectively. The pooled specificity for the detection of bone metastasis from lung cancer using ¹⁸FDG-PET–CT, ¹⁸FDG-PET, MRI and BS were 0.98 (95% CI, 0.97–0.98), 0.94 (95% CI, 0.92–0.96), 0.92 (95% CI, 0.88–0.95), 0.88 (95% CI, 0.86–0.89), respectively. The pooled DORs estimates for ¹⁸FDG-PET–CT 449.17 were significantly higher than for ¹⁸FDG-PET (118.25, P < 0.001), MRI (38.27, P < 0.001) and BS (63.37, P < 0.001). The pooled sensitivity of BS was not correlated with the prevalence of bone metastasis.

Conclusion

The results showed that both ¹⁸FDG-PET–CT and ¹⁸FDG-PET were better imaging methods for diagnosing bone metastasis from lung cancer than MRI and BS. ¹⁸FDG-PET–CT has higher diagnostic value (sensitivity, specificity and DORs) for diagnosing bone metastasis from lung cancer than any other imaging methods.     

Sensitivity and specificity of perfusion scintigraphy combined with chest radiography for acute pulmonary embolism in PIOPED II

We used the archived Prospective Investigation of Pulmonary Embolism Diagnosis II (PIOPED II) data and images to test the hypothesis that reading perfusion scans with chest radiographs but without ventilation scans, and categorizing the perfusion scan as "pulmonary embolism (PE) present" or "PE absent," can result in clinically useful sensitivity and specificity in most patients. METHODS: Patients recruited into PIOPED II were eligible for the present study if they had a CT angiography (CTA) or digital subtraction angiography (DSA) diagnosis, an interpretable perfusion scan and chest radiographs, and a Wells' score. Four readers reinterpreted the perfusion scans and chest radiographs of eligible patients. Two readers used the modified PIOPED II criteria and 2 used the Prospective Investigative Study of Pulmonary Embolism Diagnosis (PISAPED) criteria. The chest radiographs were read as "normal/near normal," "abnormal," or "nondiagnostic," and the perfusion scans were read as "PE present," "PE absent," or "nondiagnostic." The primary analysis used a composite reference standard: the PIOPED II DSA result or, if there was no definitive DSA result, CTA results that were concordant with the Wells' score as defined in PIOPED II (CTA positive and Wells' score > 2, or CTA negative and Wells' score < 6). RESULTS: The prevalence of PE in the sample was 169 of 889 (19%). Using the modified PIOPED II criteria, the sensitivity of a "PE present" perfusion scan was 84.9% (95% confidence interval [CI], 80.1%-88.8%), and the specificity of "PE absent" was 92.7% (95% CI, 91.1%-94.1%), excluding "nondiagnostic" results, which occurred in 20.6% (95% CI, 18.8%-22.5%). Using PISAPED criteria, the sensitivity of a "PE present" perfusion scan was 80.4% (95% CI, 75.9%-84.3%) and the specificity of "PE absent" was 96.6% (95% CI, 95.5%-97.4%), whereas the proportion of patients with "nondiagnostic" scans was 0% (95% CI, 0.0%-0.2%). CONCLUSION: Perfusion scintigraphy combined with chest radiography can provide diagnostic accuracy similar to both CTA and ventilation-perfusion scintigraphy, at lower cost and with lower radiation dose. With modified PIOPED II criteria, a higher proportion of scans were nondiagnostic than with CTA, and with PISAPED criteria none were nondiagnostic.     

Whole body PET for the evaluation of bony metastases in patients with breast cancer: comparison with 99Tcm-MDP bone scintigraphy

The purpose of this study was to determine the potential role of positron emission tomography (PET) using 2-[18F]-fluoro-2-deoxy-D-glucose (FDG) for the evaluation of bony metastasis compared with 99Tcm-methylene diphosphonate (99Tcm-MDP) bone scintigraphy in patients with breast cancer. Fifty-one female patients with breast cancer who had PET together with a bone scan within 1 month between September 1994 and March 1997 were included in this study. The median age was 49 years (range 29-79 years). The sensitivity, specificity and accuracy of the bone scan were 77.7%, 80.9% and 80.3%, respectively. On the other hand, for the detection of bone metastases PET had a sensitivity, specificity and accuracy of 77.7%, 97.6% and 94.1%, respectively. In the diagnosis of bony metastasis derived from breast cancer, FDG-PET was statistically superior to bone scintigraphy in its specificity. In conclusion, FDG-PET appears to be a powerful tool not only in the diagnosis of the primary lesion and soft tissue metastasis, but also in the diagnosis of bony metastasis among patients with breast cancer.     

Role of fluorodeoxyglucose-PET versus fluorodeoxyglucose-PET/computed tomography in detection of unknown primary tumor: a meta-analysis of the literature

The objectives of this study were to evaluate the diagnostic accuracy of fluorodeoxyglucose (FDG)-PET and FDG-PET/computed tomography (CT) in the detection of primary tumors in patients presenting with carcinoma of unknown primary (CUP) unidentified by conventional workup, and to compare the statistical difference between the FDG-PET and FDG-PET/CT. Twenty-eight studies (involving a total of 910 patients) published between 1990 and 2007 were reviewed. These studies evaluated the role of FDG-PET and FDG-PET/CT in the detection of unknown primary tumors after physical examination and conventional workup failed to detect a primary tumor. Systematic methods were used to identify, select, and evaluate the methodological quality of the studies as well as to summarize the overall findings of sensitivity, specificity, and detection capacity of the primary tumor. The overall sensitivity and specificity of FDG-PET in detecting unknown primary tumors were 0.78 [95% confidence interval (CI): 0.72-0.84)] and 0.79 (95% CI: 0.74-0.83), respectively. Furthermore, FDG-PET detected 28.54% of tumors that were not apparent after CUP failed to be detected by conventional workup. Data were collected on the locations of primary tumors detected by FDG-PET in 17 studies and detected by FDG-PET/CT in seven studies. Tumors from the base of the tongue accounted for 20.7% (six of 29) of all false-positive FDG-PET scans, corresponding to a false-positive rate of 28.6% (six of 29), much higher than tumors from the others. FDG-PET exhibited a lower sensitivity with respect to the tumors at the base of the tongue and tonsils, which was 68.2 and 76.7%, respectively. In the eight studies with 430 patients diagnosed with CUP by FDG-PET/CT, 31.4% (n=135) of primary tumors were detected. The pooled sensitivity and specificity were 0.81 (95% CI: 0.74-0.87) and 0.83 (95% CI: 0.78-0.87), respectively. FDG-PET and FDG-PET/CT can detect primary tumors that went undetected by physical examination and conventional workup. FDG-PET exhibited lower sensitivity with respect to the tumors at the base of the tongue and the tonsils.     

Tc-99m ciprofloxacin scans for detection of tubercular bone infection

Tc-99m MDP and Tc-99m ciprofloxacin scans were performed in 14 patients with suspected tubercular bone disease and in 2 cases of nontubercular bone infection. In 5 patients the findings were true negative. There were no false positives and 1 was false negative. The sensitivity, specificity, and positive predictive value were found to be 93, 71, and 87.5%, respectively, for detection of bone tubercular lesions. However, the test does not distinguish TB osteomyelitis from other types of osteomyelitis. Delayed 24 hour scans were found useful to differentiate between inflammatory and infective lesions. The aim of this study was to evaluate the usefulness of the Tc-99m ciprofloxacin scan as a means to detect tubercular bone disease.