Clinical significance of solitary rib hot spots on bone scans in patients with extraskeletal cancer: correlation with other clinical manifestations

PURPOSE: Bone scans showing solitary hot spots in the ribs pose diagnostic problems in patients with proved extraskeletal cancers. The authors wanted to determine the importance of solitary rib lesions and their correlation with other clinical manifestations. MATERIALS AND METHODS: The study included 199 patients with solitary rib hot spots on their bone scans. The follow-up radiographic and scintigraphic images were reviewed to determine their origin. The correlation between the occurrence of a malignant rib lesion and clinical data were determined using Pearson chi-square tests. RESULTS: Ninety-three patients had an established cause of the rib hot spot. Eleven (11.8%) had a solitary malignant rib hot spot and 82 (88.2%) had a solitary benign rib hot spot. None of the hot spots at costochondral junctions were malignant. Of the 11 patients with proved metastatic rib hot spots, 1 of 11 (9.1%) had localized bone pain, 5 of 6 (83.3%) were concordant with primary tumors, 4 of 7 (57.1%) had elevated tumor markers, and 5 of 11 (45.5%) had concurrent extraskeletal metastases. For the 82 patients with benign rib hot spots, the figures were 2 of 82 (2.4%), 43 of 57 (75.4%), 26 of 69 (37.7%), and 19 of 82 (23.2%), respectively. Statistical analysis did not show a significant correlation between the incidence of metastases in solitary rib hot spots and clinical manifestations. CONCLUSIONS: Most solitary rib hot spots on bone scans were benign. The interpretation of a solitary hot spot in the ribs is difficult even with the help of these clinical manifestations. Follow-up bone scintigrams or radiographs are needed for further investigation of solitary rib hot spots.     

Effect of Amifostine on Patients with Lung Cancer Treated with Radiotherapy or Concomitant Chemoradiotherapy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective Amifostine is clinically used as a chemical radioprotector. Nevertheless, its efficacy as a radioprotector remains controversial. Methods PubMed, Cochrane Central Register of Controlled Trials, EMBASE, China National Knowledge Infrastructure, and the references of the published results of trials on the efficacy of amifostine in patients with lung cancer and who received radiotherapy or concomitant chemoradiotherapy were searched. The pooled radiation protection efficacy, treatment response, and side effects of amifostine were calculated using RevMan software. Results Twelve randomized controlled trials involving 1000 patients with lung cancer were ultimately analyzed. Results of meta-analysis revealed that the use of amifostine reduced the risk of acute esophageal toxicity(RR, 0.56; 95% CI, 0.39-0.81; P=0.002) and pulmonary toxicity(RR, 0.42;95% CI, 0.25-0.70;P=0.001). Subgroup analysis also demonstrated that the risk of acute esophageal toxicity and pulmonary toxicity significantly reduced in patients who received chemoradiation concurrent with amifostine or radiation only. Pooled data showed that the use of amifostine did not significantly decrease the risk of late pulmonary toxicity(RR, 0.74; 95% CI, 0.45-1.19; P=0.210). Moreover, subgroup analysis demonstrated that the risk oflate pulmonary toxicity did not significantly decrease in patients who received chemoradiotherapy concomitant with amifostine(RR, 0.84; 95% CI, 0.48-1.46; P=0.540). Amifostine did not exert tumor-protective effects in partial response(RR,0.98;95% CI, 0.83-1.15; P=0.800) but improved complete response(RR, 1.50; 95% CI, 1.03-2.18; P=0.030), although publication bias was observed through Egger' s test(P=0.000). Moreover, amifostine had no effect on one-year overall survival (RR, 0.94; 95% CI, 0.81-1.09; P=0.400) and two-year overall survival(RR, 1.06; 95% CI, 0.81-1.39;P=0.680) rates. The incidence of neutropenia, a hematologic side effect of amifostine, was not significantly different(RR, 1.02; 95% CI, 0.61-1.71; P=0.940) between the amifostine and control group. The use of amifostine, however, significantly decreased the incidence of thrombocytopenia(RR, 0.45;95% CI, 0.21-0.94;P=0.030). The most common amifostine-related side effects were nausea, vomiting, and hypotension with average incidence rates of 11%, 14%, and 24%, respectively. Conclusions This systematic review showed that the concurrent administration of amifostine with radiotherapy to patients with lung cancer significantly reduced the risks of acute esophageal toxicity and acute pulmonary toxicity and decreased the incidence of thrombocytopenia without tumor-protecting effects. In addition, the toxicities of amifostine were generally controllable through clinical treatment or resting.     

Association of prostate-specific antigen levels and patterns of benign and malignant uptake detected. on bone scintigraphy in patients with newly diagnosed prostate carcinoma

The bone scan patterns of benign and malignant uptake in 432 patients with newly diagnosed prostate carcinoma were reviewed in relation to prostate-specific antigen (PSA) levels determined within 4 months of scintigraphy. Scan results were categorized in terms of likelihood of metastatic disease and anatomical locations of benign and malignant lesions were tabulated. At least one suspect focus was identified in 138 scans (32%), and metastatic bone disease was present in 38 (9%). Metastatic disease prevalence increased from 1% for PSA <20 ng x ml(-1) to 58% for PSA>100 ng x ml(-1). Among patients with PSA>20 ng x ml(-1) (n = 157), 70 (45%) had at least one bone scan finding of concern for metastases and 35 (22%) proved to have metastatic disease. Almost all scans with metastases had either limited disease (< or = 5 suspicious lesions; n = 16; 42%) or extensive metastases (> 20 abnormalities; n = 19; 50%). The majority of patients with limited skeletal metastases had PSA < 100 ng x ml(-1) (11/16; 69%), while almost all patients with extensive skeletal involvement had PSA >100 ng x ml(-1) (17/19; 89%). Among those with limited metastatic disease, most (13/16; 81%) had at least one lesion in the pelvis or sacrum; the next most common sites were in the thoracic and lumbar spine (six each; 38%). In scans with a low to moderate suspicion for bone metastases, the only anatomical site with a significantly higher prevalence of malignant than benign lesions was the pelvis.     

Bone scans with one or two new abnormalities in cancer patients with no known metastases: frequency and serial scintigraphic behavior of benign and malignant lesions

Scintigraphic, radiologic, and clinical follow-up findings were reviewed in cases in which bone scans (n = 301) showed one or two new abnormalities in patients with malignancy but no known metastases. Metastatic disease was confirmed for 25 of 231 scans (11%) with one new abnormality and for 17 of 70 scans (24%) with two new abnormalities. The prevalence of metastases was 0.06 to 0.13 for lesions in all regions of the skeleton, except the sternum (three of six) and the pelvis (10 of 32). On follow-up scans, in the absence of an interval change in therapy, 19 of 21 metastases became more intense, whereas most benign abnormalities either remained unchanged (47%) or resolved (41%). Benign lesions in the ribs, extremities, and pelvis generally resolved within 12-24 months, while most benign skull and spine abnormalities were still apparent after 35-58 months of follow-up.     

Bone scans with one or two new abnormalities in cancer patients with no known metastases: reliability of interpretation of initial correlative radiographs

To determine the reliability of radiographs obtained for correlation with bone scans showing one or two new abnormalities in cancer patients without known metastases, a retrospective study of 306 scans showing such lesions was performed. Overall, 14% of the lesions proved to be malignant. The initial radiographic interpretation was normal for 43% of the new bone scan lesions; 17% of these lesions were metastases. A benign process was identified on radiographs for 38% of the abnormalities; only one (1%) was a metastasis. Twelve percent of new bone scan lesions correlated with radiographic abnormalities considered either suggestive of or consistent with metastasis, of which 24% and 71%, respectively, proved to be metastases. In cancer patients with one or two new bone scan abnormalities, correlative radiographs showing a benign abnormality are reliable. However, if the radiographs are either normal or show findings considered suggestive of or consistent with metastasis, further evaluation or follow-up is warranted.     

Role of 18F-FDG PET/CT in differentiation of a benign lesion and metastasis on the ribs of cancer patients

ObjectiveIncidental 18-Fluoro-2-deoxyglucose positron emission tomography (¹⁸F-FDG) uptake in the ribs is a relatively common finding on positron emission tomography/computed tomography (PET/CT) images of cancer patients. This study examined the role of ¹⁸F-FDG PET/CT in differentiating between benign lesions and metastases on the ribs.MethodsThis study included 264 lesions in 172 PET/CT cases with underlying malignancy showing newly developed indeterminate ¹⁸F-FDG rib uptake between June 2009 and May 2010. Patients with more than five FDG rib uptakes or hematologic malignancy were excluded. Malignancy was confirmed either histologically or by imaging studies, and clinical follow-up with serial images was at least 6 months. The maximum standardized uptake value (SUVmax) of the rib lesion was recorded. The FDG uptake patterns (focal or segmental; discrete or non-discrete) and CT findings (evidence of fracture, soft tissue lesions, osteoblastic and/or osteolytic lesions) were recorded.ResultsThere were 206 benign lesions and 58 metastases. The SUVmax was significantly higher in the metastatic group (3.0±1.8) than in the benign group (2.5±1.1), (P= .014). For the differential diagnosis between benign and metastatic lesions, the best SUVmax cut-off was determined to be 2.4. Significant indicators for metastasis were a segmental FDG uptake pattern (OR=10.262, 95% CI 4.151–25.371), presence of an osteoblastic/-lytic lesion (OR=22.903, 95% CI 10.468 to 50.108) and the absence of fractures on CT (OR=291.629, 95% CI 39.09–2175.666).ConclusionSUVmax alone is not sufficient to differentiate benign and metastatic rib lesions in cancer patients. The diagnostic accuracy can be further increased when findings of the CT part of PET/CT are considered.     

Detection of liver metastases from pancreatic cancer using FDG PET.

We evaluated the potential of the glucose analog [18F]fluorodeoxyglucose (FDG) as a PET tracer for the hepatic staging in 168 patients designated for resective pancreatic surgery. METHODS: Metastatic liver disease was confirmed or excluded during surgery or with CT follow-up for at least 6 mo. Proven metastases were then retrospectively identified on preoperative CT (gold standard). Hepatic PET scans of all patients were interpreted blindly. Any focal FDG uptake was considered malignant. Both proven hepatic metastases and suspicious hepatic PET lesions were then compared, lesion by lesion, with CT. Standardized uptake values (SUV) and tumor-to-liver ratios (T/L) were determined for the most intense lesion of each patient. RESULTS: Sensitivity of FDG PET was 68% (15 of 22 patients). The lesion detection rate was 97% (28 of 29 metastases) for lesions >1 cm and 43% (16 of 37 metastases) for lesions < or = 1 cm. Specificity was 95% (138 of 146 patients). Six of eight patients with false-positive results had marked intrahepatic cholestasis (versus 3 of 15 patients with true-positive lesions), one had an infrahepatic abscess and one had a right basal pulmonary metastasis. The SUV and T/L were 4.6+/-1.4 and 2.3+/-1.1, respectively, for malignant lesions and 4.1+/-1.5 and 1.9+/-0.3, respectively, for false-positive lesions and therefore are of limited value. CONCLUSION: FDG PET provides reliable hepatic staging for lesions >1 cm. False-positive results are associated with the presence of marked intrahepatic cholestasis. For lesions < or = 1 cm, FDG PET can define malignancy in 43% of suspicious CT lesions in the absence of dilated bile ducts.     

The benefit of SPECT when added to planar scintigraphy in patients with bone metastases in the spine.

PURPOSE: This study compared the efficiency of SPECT with planar bone scans in differentiating malignant from benign lesions and in detecting metastases to the spine. METHODS: Planar scintigraphy and SPECT were performed in 37 patients with low back pain without known malignancy and in 38 patients with confirmed malignancy. The type, location, and intensity of tracer accumulation were compared on the planar and SPECT scans. The malignant or benign nature of lesions was proved by radiologic methods, histologic findings, 6 month follow-up, or all of these. RESULTS: More metastases were detected by SPECT (SPECT, 58 of 64; planar, 42 of 64; P < 0.01). In three of seven patients with known malignancy who had a normal result of planar scan, only SPECT detected metastases. Fifty-nine metastases were radiologically mainly osteolytic, one was osteoblastic and four were mixed. Most lesions showed increased radioactivity (40 of 42 on planar scans vs. 45 of 58 on SPECT) and 2 of 42 (5%) vs. 12 of 58 (21%) were cold with marginally increased uptake. One of 58 metastases was a cold lesion seen on SPECT only. Lesions were more often malignant than benign when seen on SPECT in a pedicle (n = 5; malignant = 3, benign = 2), in the body and pedicle (n = 22; malignant = 14, benign = 8), within the vertebral body (n = 5; malignant = 4, benign = 1) and in the whole vertebra (n = 6; malignant = 4, benign = 2). The lesion to background ratio was higher on SPECT than on planar scans (SPECT, 2.26; planar scans, 1.86; P < 0.05 in malignant lesions). CONCLUSIONS: SPECT of the spine improved the diagnostic accuracy of bone scans when added to a planar scan in patients with known malignancy and clinical suspicion of spinal metastases when the planar scan was borderline abnormal. It helps in differentiating between benign and malignant lesions of the spine.     

Does a computer-aided detection algorithm in a second read paradigm enhance the performance of experienced computed tomography colonography readers in a population of increased risk?

We prospectively determined whether computer-aided detection (CAD) could improve the performance characteristics of computed tomography colonography (CTC) in a population of increased risk for colorectal cancer. Therefore, we included 170 consecutive patients that underwent both CTC and colonoscopy. All findings >or=6 mm were evaluated at colonoscopy by segmental unblinding. We determined per-patient sensitivity and specificity for polyps >or=6 mm and >or=10 mm without and with computer-aided detection (CAD). The McNemar test was used for comparison the results without and with CAD. Unblinded colonoscopy detected 50 patients with lesions >or=6 mm and 25 patients with lesions >or=10 mm. Sensitivity of CTC without CAD for these size categories was 80% (40/50, 95% CI: 69-81%) and 64% (16/25, 95% CI: 45-83%), respectively. CTC with CAD detected one additional patient with a lesion >or=6 mm and two with a lesion >or=10 mm, resulting in a sensitivity of 82% (41/50, 95% CI: 71-93%) (p = 0.50) and 72% (18/25, 95% CI: 54-90%) (p = 1.0), respectively. Specificity without CAD for polyps >or=6 mm and >or=10 mm was 84% (101/120, 95% CI: 78-91%) and 94% (136/145, 95% CI: 90-98%), respectively. With CAD, the specificity remained (nearly) unchanged: 83% (99/120, 95% CI: 76-89%) and 94% (136/145, 95% CI: 90-98%), respectively. Thus, although CTC with CAD detected a few more patients than CTC without CAD, it had no statistically significant positive influence on CTC performance.     

Staging of patients with carcinoma of the breast by bone scans? [author's transl)

Bone scans were performed in 170 patients with widespread breast cancer and metastases which were confirmed by the clinical course. In 82% a positive x-ray and in 95% a positive bone scan could be demonstrated. In 43 patients without bone metastases the ratio of false positive scans was 5%. Seventeen out of 50 patients with early cancer had abnormal scans. In 12 cases there were metastases proven by follow-up of at least 18 months. Assuming an incidence of 25% for bone metastases in patients with early breast cancer, bone scans with a sensitivity and specificity of 95% will be valid in staging. To validate this high incidence we investigated a second group of 97 patients with early cancer in a prospective study: in only 3 cases there was an abnormal scan. Using this low incidence bone scanning is calculated to be not valid for staging of breast cancer.     

Decreased 99mTc sulfur colloid activity in healed rib fractures

This report describes 2 patients in whom focal areas of decreased 99mTc sulfur colloid marrow activity were associated with callus formation and healing rib fractures in one case and rib fractures with bony bridging in the second. Since bone marrow scans are occasionally used to select appropriate sites for marrow biopsy in patients with suspected metastatic disease, radiographic correlation of "cold" lesions on marrow scans is recommended prior to biopsy to exclude fracture with callus formation as a benign cause of the abnormality.     

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.     

Association between number and sites of new bone scan abnormalities and presence of skeletal metastases in patients with breast cancer

Review of 1,441 bone scans performed on 242 breast cancer patients without known skeletal metastases identified 239 scans with new abnormalities. Findings on 54 of these 239 scans (23%) represented bone metastases. The proportion of scans reflecting metastases, grouped by the number of new abnormalities, was: (1) 20/182 (11%); (2) 9/26 (35%); (3) 4/9 (45%); (4) 1/2 (50%); greater than or equal to 5-20/20 (100%). When metastatic disease presented as a bone scan with 1-4 new abnormalities, the spine was the most common site of involvement (18 of 34 (53%)), followed by the skull (5/34; 15%), extremities and sternum (each 4/34; 12%). Rib lesions were the most common new findings on scans with less than 5 new abnormalities (seen on 76 of 219 scans (35%)) but only infrequently represented metastases (n = 2). Considering as indicative of malignancy only, those bone scans which demonstrated either (a) greater than or equal to 5 new abnormalities, (b) initial radiographic correlation suggestive of metastases, or (c) thoracic spine lesions with normal correlative radiographs, the presence of skeletal metastatic disease could be predicted with a sensitivity of 0.80 and a specificity of 0.94.     

Integrated imaging using MRI and 123I metaiodobenzylguanidine scintigraphy to improve sensitivity and specificity in the diagnosis of pediatric neuroblastoma

OBJECTIVE: The objectives of this study were to compare MRI and iodine-123 ((123)I) metaiodobenzylguanidine (MIBG) scintigraphy in the detection of neuroblastoma lesions in pediatric patients and to assess the additional value of combined imaging. MATERIALS AND METHODS: Fifty MRI and 50 (123)I MIBG examinations (mean interval, 6.4 days) were analyzed retrospectively with regard to suspected or proven neuroblastoma lesions (n = 193) in 28 patients. MRI and MIBG scans were reviewed by two independent observers each. Separate and combined analyses of MRI and MIBG scintigraphy were compared with clinical and histologic findings. RESULTS: With regard to the diagnosis of neuroblastoma lesion, MIBG scintigraphy, MRI, and combined analysis showed a sensitivity of 69%, 86%, and 99% and a specificity of 85%, 77%, and 95%, respectively. On MRI, 15 false-positive findings were recorded: posttherapeutic reactive changes (n = 10), benign adrenal tumors (n = 3), and enlarged lymph nodes (n = 2). On MIBG scintigraphy, 10 false-positive findings occurred: ganglioneuromas (n = 2), benign liver tumors (n = 2), and physiologic uptake (n = 6). Thirteen neuroblastoma metastases and two residual masses under treatment with chemotherapy were judged to be false-negative findings on MRI. Two primary or residual neuroblastomas and one orbital metastasis were misinterpreted as Wilms' tumor, reactive changes after surgery, and rhabdomyosarcoma on MRI. Thirty-two bone metastases, six other neuroblastoma metastases, and one adrenal neuroblastoma showed no MIBG uptake. On combined imaging, one false-negative (bone metastasis) and three false-positive (two ganglioneuromas and one pheochromocytoma) findings remained. CONCLUSION: In the assessment of neuroblastoma lesions in pediatric patients, MRI showed a higher sensitivity and MIBG scintigraphy a higher specificity. However, integrated imaging showed an increase in both sensitivity and specificity.     

Factors influencing visualization of vertebral metastases on MR imaging versus bone scintigraphy

OBJECTIVE: The purpose of this study was to investigate whether the location and size of vertebral body metastases influence the difference in detection rates between MR imaging and bone scintigraphy. MATERIALS AND METHODS: We retrospectively evaluated the vertebral body lesions detected on MR imaging in 74 patients with known widely disseminated metastatic disease. Three radiologists independently reviewed the MR images and bone scintigraphs. MR imaging findings included lesion size and its spatial relationship to the bony cortex (intramedullary, subcortical, and transcortical) and results were correlated with those of planar technetium 99m bone scintigraphy. RESULTS: Findings on bone scans were negative for all intramedullary lesions without cortical involvement shown on MR imaging, regardless of their size. Findings on bone scans (71.3% for transcortical and 33.8% for subcortical) were frequently positive for lesions with cortical involvement (trans- or subcortical), and the probability of positive findings on bone scans was also influenced by the lesion size. Statistical analysis showed a positive correlation among cortical involvement, lesion size, and positive findings on bone scintigraphy (p < 0.0001). CONCLUSION: Location (the presence of cortical bone involvement on MR imaging) and size of the vertebral body metastases appear to be important contributing factors to the difference in detection rates between MR imaging and bone scintigraphy. Cortical involvement is likely the cause of positive findings on bone scans. Early vertebral metastases tend to be small and located in the medullary cavity without cortical involvement, and therefore, findings may be positive on MR images but negative on bone scans.     

Tc-99m HMDP bone scintigraphic findings in association with concurrent serum osteocalcin measurements

Osteocalcin is a noncollagenous bone protein produced by osteoblasts. Increase in serum osteocalcin level reflects osteoblast activity with acceleration of bone formation. To evaluate the correlation of Tc-HDP bone scintigraphic findings and concurrent serum osteocalcin, serum osteocalcin values of 40 consecutive patients were measured by radioimmunoassay at the time of initial referral for bone studies. These patients, all males aged 23-93, were studied for various disease entities, including prostate carcinoma. The results of the assay were categorized into three groups (gp) as follows: 17 at normal (1.8 to 6.6 ng/ml) level (gp 1), 21 low (gp 2), and two high (gp 3). Only one bronchogenic carcinoma patient with a high level had a right iliac lesion suggesting metastasis. The bone scans of nine patients with normal or low levels showed positive metastases. Two patients with stress fractures as shown on bone scans had normal levels. The images of patients with disparity between serum osteocalcin and positive bone lesions may be interpreted as follows: Instead of osteoblastic activity resulting in the synthesis and/or release of osteocalcin, area(s) of increased uptake in the bone scan may be predominantly reflecting increased regional blood flow and decreased sympathetic tone, resulting in an increase in bone-agent deposition.     

Prevalence and patterns of bone metastases detected with positron emission tomography using F-18 FDG

PURPOSE: The aim of this retrospective study was to report the prevalence and imaging characteristics of bone metastases detected with F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) and, when possible, compare these findings with the performance of bone scans in the same patients. METHODS: The reports of 403 patients with histologically proved malignant disease who underwent a PET scan for initial or post-therapeutic staging were reviewed for the presence of possible bone metastases. Based on the final diagnosis confirmed by histopathologic analysis or clinical follow-up, the PET findings of patients with positive bone metastases were evaluated in terms of location, intensity, and patterns. When the PET scan was positive, the PET results were compared with the findings of available bone scans. RESULTS: PET studies suggested the presence of bone metastases in 38 patients (9%). No follow-up data were available for 9 patients, and the remaining 29 were evaluated further. Of these patients, 6 had false-positive findings, whereas bone metastatic involvement was clinically confirmed in 23 patients. The primary malignant findings included lung cancer (n = 9), esophageal cancer (n = 3), lymphoma (n = 2), melanoma (n = 2), thyroid cancer (n = 2), breast cancer (n = 1), colon cancer (n = 1), prostate cancer (n = 1), testicular cancer (n = 1), and nasopharyngeal cancer (n = 1). On PET, 5 patients had a solitary metastatic focus (22%), and the remaining 18 patients had multiple lesions (78%). The vertebrae were the most frequently involved bones (74%), followed by pelvic bones (70%), ribs (65%), upper extremities including the scapula (48%), sternum (43%), and lower extremities (43%). The patterns of abnormal uptake were classified into three groups: focal (15 patients, 65%), diffuse (2 patients, 9%), and a mixed pattern (6 patients, 26%). Most of the lesions showed intense abnormal uptake (18 patients, 78%); 5 patients had both intense and moderate FDG uptake. Thirteen of the 23 patients with confirmed bone metastases also had a bone scan, which revealed positive bone disease in all of these patients. However, PET consistently revealed more metastatic foci than did the bone scan on a lesion basis. CONCLUSIONS: The most frequent pattern of detectable bone metastases with FDG-PET imaging was multiple foci of intense uptake. PET revealed more lesions than did bone scanning, independent of the type of cancer or location of bone involvement, in patients who were accurately diagnosed by FDG-PET imaging.     

Risk factors for pneumothorax and bleeding after CT-guided percutaneous coaxial cutting needle biopsy of lung lesions.

PURPOSE: To evaluate risk factors for pneumothorax and bleeding after computed tomography (CT)-guided percutaneous coaxial cutting needle biopsy of lung lesions. MATERIALS AND METHODS: This study involved 117 consecutive patients with 117 intrapulmonary lesions. Statistical analysis of factors related to patient characteristics, lung lesions, and biopsy technique was performed to determine possible contribution to the occurrence of pneumothorax and bleeding. Interactions between related factors were considered to prevent colinearity. RESULTS: Pneumothorax occurred in 12% (14 of 117) of patients. Needle aspiration of two moderate asymptomatic pneumothoraces were performed; there was no chest tube insertion. Lesion depth (P =.0097), measured from the pleural puncture site to the edge of the intrapulmonary lesion along the needle path, was the single significant predictor of pneumothorax. The highest risk of pneumothorax occurred in subpleural lesions 2 cm or shorter in depth (this represented 33% of lung lesions but caused 71% of all pneumothoraces; OR = 7.1; 95% CI, 1.3-50.8). Bleeding presented as lung parenchyma hemorrhage and hemoptysis in 30 patients (26%). Hemoptysis occurred in four patients (3%). Univariate analysis identified lesion depth (P <.0001), lesion size (P <.015), and pathology type (P =.007) as risk factors for bleeding. Multivariate logistic regression analysis identified lesion depth as the most important risk factor, with the highest bleeding risk for lesions more than 2 cm deep (14% of lesions caused 46% of all bleeding; OR = 17.3; 95% CI, 3.3-121.4). CONCLUSIONS: In CT-guided coaxial cutting needle biopsy, lesion depth is the single predictor for risk of pneumothorax, which occurs at the highest rate in subpleural lesions. Increased risk of bleeding occurs in lesions deeper than 2 cm.     

Potential of (99m)Tc-MIBI for detecting bone marrow metastases.

In this study, we evaluated the potential of (99m)Tc-hexakis-2-methoxyisobutylisonitrile (MIBI) for detecting bone metastases in comparison with a conventional bone tracer. METHODS: (99m)Tc-MIBI and (99m)Tc-hydroxymethylene diphosphonate (HMDP) scans were obtained from 99 patients with proven malignant diseases and suspected bone metastases. We compared 373 lesions that showed abnormal uptake on (99m)Tc-MIBI scans or (99m)Tc-HMDP scans (or both). RESULTS: Bone metastases were confirmed in 334 of 373 lesions. Thirty-nine lesions on (99m)Tc-HMDP scans had false-positive findings, but only 2 of these lesions had false-positive findings on (99m)Tc-MIBI scans. (99m)Tc-MIBI and (99m)Tc-HMDP scans were equivalent in 168 of 334 lesions (50.3%). (99m)Tc-MIBI scans correctly detected more lesions than (99m)Tc-HMDP scans: 284 lesions (85.0%) versus 218 lesions (65.3%) (P < 0.005), respectively. (99m)Tc-MIBI scans showed a markedly higher sensitivity for detecting metastases in the femur and humerus compared with (99m)Tc-HMDP scans: 97 of 98 lesions (99.0%) versus 35 of 98 lesions (35.7%) (P < 0.005) and 21 of 22 lesions (95.5%) versus 11 of 22 lesions (50.0%) (P < 0.005), respectively. (99m)Tc-HMDP scans of 17 patients showed no abnormal images. However, (99m)Tc-MIBI scans correctly detected bone metastases, and subsequent development of multiple lesions was observed on follow-up (99m)Tc-HMDP scans of 15 patients. (99m)Tc-MIBI scans were superior to (99m)Tc-HMDP scans in the detection of metastases attributed to breast cancer, multiple myeloma, and hepatoma. On the contrary, (99m)Tc-MIBI scans were less sensitive than (99m)Tc-HMDP scans for detecting bone metastases attributed to prostate cancer in the other skeletal sites except for femur and humerus. CONCLUSION: (99m)Tc-MIBI scans have better sensitivity for detecting bone metastases and provide more specific complementary findings than conventional bone scans. (99m)Tc-MIBI accumulation attributed to bone marrow metastases may occur at an early stage, before the bone remodeling process in the surrounding bone can be detected on conventional bone scans.     

The implication of hot spots on bone scans within the irradiated field of breast cancer patients treated with mastectomy followed by radiotherapy

Objective  To analyze the implication of abnormal hot spots in the irradiated field of patients treated with mastectomy followed by radiotherapy for breast cancer. Methods  We reviewed 1842 consecutive bone scans performed on 292 patients treated with a modified radical mastectomy and followed by radiotherapy. If abnormal hot spots at the irradiated sites were detected in the bone scans, we evaluated further studies to determine whether bone metastases were present. Radiation was given using 4 or 6 MV X-rays at a dosage of 50.4 Gy during 5.5 weeks with a dosage per fraction of 1.8 Gy. The follow-up period was 25–136 months (median 57 months). Results  Sixty patients (20.6%) developed bone metastasis. Solitary rib metastases were identified in four patients; all were detected outside of the irradiated field. Of 232 patients who did not develop bone metastases, hot spots in the irradiated field were detected in 30 patients (12.9%). A simple rib facture at the site of a hot spot was demonstrated in four patients. The cumulative incidence of hot spots at 5 years was 12.9%. The cumulative incidence of hot spots was more common in postmenopausal women, patients who were less than 60 kg, patients who received adjuvant hormonal therapy and patients who had radiation that included the supraclavicular area. Conclusions  We confirmed that the hot spots within the irradiated fields might be benign, especially in patients who were postmenopause, had a low body weight, received adjuvant hormonal therapy and who had radiation that included the supraclavicular area.