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.     

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.     

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.     

The value of CT scanning and percutaneous fine needle aspiration of adrenal masses in biopsy-proven lung cancer.

Pre-operative CT scans of 546 patients with biopsy-proven primary bronchial carcinoma were reviewed. Twenty-two patients had a solid adrenal tumour (2 bilateral). Sixteen underwent percutaneous fine needle aspiration (FNA). Malignant cells were aspirated in five, eight revealed benign cells and in three cases there was insufficient material for diagnostic purposes. Six patients did not undergo FNA, four of these were considered to have benign adenomas on CT. This was confirmed by the unchanged CT image at more than 21 months follow-up. The five subjects with FNA-proven metastases died at a median of 14 months (range 3-24 months). All five would have been regarded as operable on their staging chest CT scan. Five patients with a negative biopsy underwent surgery, two died of metastases at 6 and 11 months respectively and one died of post-operative complications. The other two have unchanged adrenal lesions on CT at 9 months and 25 months. The CT appearances of these lesions were analysed. Well defined, low attenuation lesions which had a smooth attenuation rim or only involved part of the gland were benign and the survivors had unchanged CT appearances at follow-up (six lesions in five patients). Of these four lesions were less than or equal to 2 cm in diameter. Low attenuation lesions without a rim were malignant (n = 2). These latter both measured more than 2 cm in diameter. The CT appearances of many adrenal lesions were insufficiently distinctive to exclude malignancy and biopsy was necessary to establish a diagnosis.     

Evaluation of metastatic bone disease with pentavalent 99Tc(m)-dimercaptosuccinic acid: a comparison with whole-body scanning and 4/24 hour quantitation of vertebral lesions

The aim of this study was to establish the value of 99Tcm(V)-DMSA scintigraphy in the detection of metastatic bone lesions and compare the results to 99Tcm-MDP bone scintigraphy. Thirty-four patients presenting with metastatic bone disease (Group 1) and 12 controls with degenerative skeletal lesions (Group 2) were studied. Conventional bone scanning and 99Tcm(V)-DMSA whole-body scanning were performed on all patients. All scans were interpreted visually. Furthermore, lesion-to-normal bone ratios (L/N) in vertebral metastases on the 4 and 24 h bone scans were obtained in 58 lesions of cancer patients and in 23 benign (degenerative) vertebral lesions of the control group. 99Tcm-MDP L/N ratios at 24 h (3.08 +/- 0.32) were significantly higher than those at 4 h (2.48 +/- 0.24) in the malignant foci (P < 0.001). No significant difference was observed in benign lesions (P > 0.05). In 167 (164 metastatic, 3 traumatic) of 186 99Tcm-MDP positive lesions (90%) of Group 1, 99Tcm(V)-DMSA uptake was observed. The remaining 19 lesions (10%) were 99Tcm(V)-DMSA negative. Fourteen of these 19 sites were diagnosed as benign. The remaining five foci were malignant. In four lung cancer metastases showing no 99Tcm-MDP uptake, 99Tcm(V)-DMSA uptake was observed. There was no 99Tcm(V)-DMSA accumulation in any of the 99Tcm-MDP positive degenerative lesions of Group 2. All quantitatively evaluated (n = 42) vertebral metastatic foci and two compression fractures in Group 1 showed 99Tcm(V)-DMSA accumulation and an increased 99Tcm-MDP L/N ratio at 24 h. A total of 36 degenerative lesions (Groups 1 and 2) and one compression fracture (Group 1) showed neither 99Tcm(V)-DMSA uptake nor an increased 99Tcm-MDP L/N ratio at 24 h. Our results indicate that quantitative 4/24 h analysis of vertebral lesions on 99Tcm-MDP scans has a similar diagnostic value to 99Tcm(V)-DMSA imaging in the detection of bone metastases. However, the accumulation of 99Tcm(V)-DMSA in four lung cancer metastases showing no 99Tcm-MDP uptake is encouraging and justifies further research in patients with proven bone metastases and negative bone scans.     

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.     

Radiofrequenzablation (RFA) von Lungenmetastasen kolorektaler Karzinome (KRK)—Ergebnisse nach einem Jahr

Assess the safety and evidence of efficacy of RFA for colorectal (CRC) lung metastases with follow up to 1 year. Twenty-three patients had percutaneous RFA for 52 colorectal pulmonary metastases under fluoro-CT. Patients received IV conscious sedation and local analgesia with routine hospitalisation/monitoring for 24 h post RFA. Patients had CT scanning at 1 month and then 3 monthly with serum CEA assessment monthly and 3 monthly. All ablations were technically successful. Tumor diameter ranged from 0.3 to 4.2 cm. Pneumothorax occurred in 43% (10 of 23) of patients. Six patients required intercostal chest drain placement. Six patients had a second RFA, 4 for new lesions and 2 patients had a previously treated lesion retreated. Median admission was 2.0 days (range 1-9). Median follow-up is 428 days (range 173-829), with data reported to 1 year in this paper. Five patients died at 5, 6, 8, 8 and 12 months post RFA from extra-pulmonary (1) or widespread (4) disease. One patient developed malignant pleural effusion at 6 months after RFA. Cavitation was seen in nine treated lesions (17%), all resolved with scar tissue contraction by 12 months. Eighteen patients with CT scan follow-up at one year have 40 lesions classified as: disappeared (17), decreased (5), stable/same size (4), increased (14). Percutaneous imaging-guided RFA of multiple CRC pulmonary metastases is a minimally invasive treatment option with modest morbidity. A significant proportion of patients show good evidence of successful local control at one year.     

CT imaging findings of pulmonary neoplasms after treatment with radiofrequency ablation: results in 32 tumors

OBJECTIVE: The purpose of this study is to describe the CT appearance of thoracic neoplasms after treatment with radiofrequency ablation (RFA). MATERIALS AND METHODS: Thirty-two thoracic neoplasms in 26 patients had pulmonary RFA and imaging follow-up. Fourteen neoplasms were primary lung cancer and 18 were metastases. The mean pretreatment neoplasm size was 3.1 cm (range, 1.0-7.0 cm), and the average number of neoplasms treated per patient was 1.2 (range, 1-3). The mean follow-up was 10.1 months (range, 1-30 months). Imaging findings on CT were evaluated by three radiologists and documented by consensus. RESULTS: The most common finding immediately after treatment was peripheral ground-glass opacity surrounding the treated neoplasm, seen in 27 of 32 tumors (84%). This rapidly resolved in all but one patient by the end of the first month. Cavitation was seen in 10 of 32 tumors (31%) on follow-up CT and was most common in neoplasms in the inner two thirds of the lung and adjacent to a segmental bronchus. Sixty percent of the cavitations decreased in size on follow-up scans. Ten of 32 tumors (31%) that did not develop cavitation developed bubble lucencies on follow-up CT. Pleural thickening was found in 12 of 22 (55%) parenchymal neoplasms, and linear opacifications were seen between the treated lesion and adjacent pleura in 14 of 22 parenchymal tumors (64%). Pleural effusions were seen in four patients (15%). Fourteen of 22 tumors (64%) with follow-up imaging at 1 month enlarged from pretreatment CT scans. At 3 and 6 months after RFA, the majority remained stable in size. CONCLUSION: Peripheral ground-glass opacity, cavitation, bubble lucencies, and pleural changes are common findings on CT after RFA. Many treated neoplasms increase in size from baseline on 1- to 3-month follow-up CT scans and then remain stable thereafter. Enlargement of a treated tumor after 6 months is felt to represent local recurrence. Stability of a treated lesion beyond 6 months does not guarantee continued stability.     

Radiation-induced insufficiency fractures of the pelvis: evaluation with 99mTc-methylene diphosphonate scintigraphy.

99mTc-methylene diphosphonate (99mTc-MDP) bone scans in 80 patients, 30-80 years old (average, 62 years old) with uterine cancer who received high doses of radiation (10-60 Gy; average, 46 Gy) were reviewed retrospectively to evaluate the frequency of pelvic insufficiency fractures caused by radiotherapy and to study the appearance of the fractures on bone scans. Bone scans in 29 of 80 patients showed abnormalities in the pelvis: insufficiency fractures were identified in 27 patients (34%) and osseous metastases were found in two patients (3%). The fractures and metastases were diagnosed by CT and were confirmed by observing the patients' clinical courses. Fractures were identified in 27 (39%) of 69 postmenopausal women and in none of 11 premenopausal patients (p greater than .05). Fractures were found in 21 (84%) of 25 patients who had pelvic pain and in six (11%) of 55 patients who were asymptomatic (p greater than .001). Scintigrams in patients with fractures showed more than one fracture in most patients (85%), and fractures were often symmetric (67%). Scintigrams in two patients with osseous metastases showed increased activity in an iliac wing that was outside the radiation field. Our results suggest that a marked increase in insufficiency fractures occurs after radiation therapy, especially in postmenopausal patients. A symmetric area of increased uptake of radionuclide is a characteristic scintigraphic appearance of an insufficiency fracture.     

Follow-up of breast lesions diagnosed as benign with stereotactic core-needle biopsy: frequency of mammographic change and false-negative rate.

PURPOSE: To determine how often lesions diagnosed as benign with stereotactic core-needle biopsy (SCNB) change at follow-up mammography and to determine the optimal follow-up strategy and the delayed false-negative rate. MATERIALS AND METHODS: From July 1992 through December 1995, 355 of 540 cases (66%) in which SCNB yielded benign results were managed with follow-up mammography. Mammographic follow-up was available for 298 of these cases (84%). Follow-up mammography reports were reviewed. When a change was reported, pre- and postbiopsy mammograms, pathology reports, and results of subsequent mammographic follow-up were reviewed. RESULTS: Mammographic change occurred in 21 of 298 cases (7%) at intervals of 6-55 months (mean, 20 months). Change occurred after initial mammographic stability in 10 of 21 cases. Repeat biopsy was performed in 18 of 21 cases. Malignancy was diagnosed in two cases: one mass that changed at 6 months and one case of microcalcifications that changed at 24 months. This represented a delayed false-negative rate of 2% (two of 105 malignancies among 540 biopsies). CONCLUSION: A small percentage of cases diagnosed as benign with SCNB will change on follow-up mammograms, which may necessitate repeat biopsy. These results suggest that 6-month follow-up for cases that yield nonspecific benign results at SCNB and yearly screening mammography for cases with specific benign results is a reasonable management strategy.     

(99m)Tc-MDP scintigraphic findings in children with leukemia: value of early and delayed whole-body imaging.

The purpose of this study was to reveal the bone scan abnormalities in children with leukemia and to show the value of whole-body scanning in early and delayed phases. METHODS: From a database of all patients with a diagnosis of leukemia from January 1990 to April 2000, 12 children (9 male, 3 female; mean age, 8.0 y; age range, 4.7--13.2 y) were identified for whom the diagnosis of leukemia was suggested on the basis of bone scans obtained as part of the initial work-up for unexplained skeletal pain. Early and delayed whole-body bone scans and radiographs were reviewed retrospectively. Areas of abnormal uptake on early and delayed phases were categorized into locations: metaphysis--diaphysis--epiphysis (MDE), pelvis, ribs, spine, and others. MDE lesions included abnormalities in the metaphysis extending into the diaphysis for some length: metaphysis/diaphysis, metaphysis only, diaphysis only, epiphysis only, and the entire bone. Pelvic and spine lesions were further characterized as focal or diffuse. RESULTS: Ten patients had lesions in 2 or more locations on both phases. Two patients had multiple lesions on the early scans but only rib lesions on the delayed scans. Lesions correlated with symptomatic sites in 8 patients on the delayed scans and in 11 patients on the early scans. The most common sites of abnormalities on the delayed scans were metaphyseal/diaphyseal, pelvis (focal), and ribs. The most common locations of lesions on the early scans were metaphyseal/diaphyseal, pelvis (diffuse or focal), and spine. More metaphyseal/diaphyseal lesions were seen on the early scans than on the delayed scans. Diffuse involvement of the pelvis and spine was seen only on the early phase. However, rib lesions were seen more frequently on the delayed scan. CONCLUSION: Early whole-body imaging in conjunction with delayed whole-body scanning may enhance the diagnostic accuracy of bone scanning in the evaluation of children with skeletal pain of obscure etiology, such as that associated with leukemia.     

CT findings after hepatic chemoembolization.

Hepatic arterial chemoembolization (CE) with a mixture of particulate collagen and chemotherapeutic agents was evaluated as therapy for hepatic metastases from colorectal carcinoma. This article describes the characteristics sequential pattern of change seen on liver CT scans following CE. Thirty CT scans were performed on seven patients who had undergone a total of 11 CE procedures. All patients had baseline, immediate postprocedural, and follow-up CT exams at 1 to 2 month intervals following CE. Immediate post-procedural CT scans mapped the area of embolization owing to the density of the contrast mixed with the CE agents. Some lesions seen easily on baseline were more difficult to see as they became isodense with normal liver. Reflux of embolic material into the cystic artery and gallbladder wall was also observed on postprocedural scans in three patients. In all patients, early follow-up scans (1 month after CE) demonstrated changes in lesions seen on baseline scans consistent with tumor necrosis. This was corroborated by a decrease in carcinoembryonic antigen (CEA) levels. In three patients, however, low attenuation regions developed in areas in which there had been no lesion before. The significance of these is uncertain, but the low CEA values and the subsequent evolution in appearance of these sites on CT suggest that they were regions of hepatic ischemia/infarction as opposed to heretofore unidentifiable metastases, now "unmasked." Intermediate follow-up scans (2-3 months) revealed maximal effect on tumor volume, with a decrease of > or = 25% in five of seven patients (71%). Late follow-up scans (> or = 3 months after the last CE) confirmed recurrent disease and new lesions in all cases.     

Detection of unexpected additional primary malignancies with PET/CT.

This study evaluated the yield of whole-body (18)F-FDG PET/CT for the detection of unexpected (18)F-FDG-avid additional primary malignant tumors in patients being evaluated by PET/CT for known or suspected malignances. METHODS: Reports from whole-body (18)F-FDG PET/CT scans from June 2001 to June 2003 were reviewed, and 1,912 patients (924 men and 988 women; mean age +/- SD, 58.9 +/- 13.9 y) who had been scanned for known or suspected malignant lesions were included in this study. The sites of known or suspected primary tumors included lung (28.6%), colon or rectum (12.4%), head or neck (12.1%), lymph nodes (10.9%), breast (7.6%), gynecologic organs (7.1%), genitourinary organs (4.2%), esophagus (3.6%), skin (melanoma) (3.5%), pancreas (2.5%), bone or soft tissue (2.2%), and other sites (5.4%). Lesions that were newly discovered on PET/CT, had not been previously detected by other modalities, and were atypical in location for metastases on the PET/CT study were interpreted as suggestive of a new primary malignant tumor. These abnormalities were compared with the final diagnosis obtained from the medical records, including pathologic reports. RESULTS: PET-positive lesions suggestive of new primary malignant tumors were found in 79 (4.1%) of 1,912 patients. In 22 (1.2%) of 1,912 patients, these lesions were pathologically proven to be malignant. Proven sites were lung (7 lesions), thyroid (6 lesions), colon (4 lesions), breast (2 lesions), esophagus (2 lesions), bile duct (1 lesion), and head and neck other than thyroid (1 lesion). Two new lesions in the lung and the thyroid were proven malignant in 1 patient. In 17 patients, the treatment plan was changed and the new lesion was surgically resected after the PET/CT examination. In 10 patients, PET was falsely positive after pathologic assessment. False-positive sites included thyroid (5 lesions), uterus (2 lesions), head and neck other than thyroid (2 lesions), and lung (1 lesion). In 8 patients, the PET-positive lesions were considered benign after clinical follow-up of at least 8 mo. In 39 patients, the follow-up record was not yet available and the final diagnosis of the detected lesion has not yet been resolved. CONCLUSION: Whole-body PET/CT detected new, unexpected (18)F-FDG-avid primary malignant tumors in at least 1.2% of patients with cancer.     

Role of US-guided fine-needle aspiration with on-site cytopathologic evaluation in management of nonpalpable breast lesions

RATIONALE AND OBJECTIVES: The purpose of this study was to evaluate the accuracy of ultrasound (US)-guided fine-needle aspiration (FNA), with radiographic follow-up or surgical excision, in conjunction with on-site cytopathologic support in the management of nonpalpable breast lesions. MATERIALS AND METHODS: The findings of 266 consecutive mammographically or sonographically identified, nonpalpable lesions (228 patients) that underwent US-guided FNA were examined retrospectively. Clustered microcalcifications did not undergo biopsy with this method. Patients who underwent follow-up excisional biopsy or mammography with a duration of at least 24 months were included in the study. RESULTS: In all, 117 lesions met criteria for inclusion, of which 85 (73%) were diagnosed as benign at cytopathologic evaluation and underwent mammographic follow-up of at least 24 months (range, 24-67 months; mean, 36 months). Thirty-two lesions (27%) had either malignant or atypical cytopathologic findings, for which surgery was recommended. Eleven (9%) of the 32 had malignant cytopathologic findings from initial US-guided FNA, which were confirmed at surgical excision. The remaining 21 lesions (18%) were diagnosed as atypical on the basis of US-guided FNA results. Of these, 18 lesions underwent excisional biopsy: Two were diagnosed as carcinoma (not otherwise specified), and 16 were diagnosed with a variety of benign disorders. The remaining three patients with atypical lesions chose mammographic follow-up rather than surgical diagnosis, and their conditions have remained stable for more than 24 months. Of the 85 benign cases, one changed during follow-up (12 months) and underwent repeat biopsy, with malignancy noted. The sensitivity of US-guided FNA in identifying malignant lesions was 93% (13 of 14), and the specificity of a benign finding was 100% (102 of 102). The positive and negative predictive values of US-guided FNA supported by on-site cytopathologic evaluation were 100% (13 of 13) and 99% (102 of 103), respectively. CONCLUSION: Supported by appropriately trained on-site cytopathologists and in conjunction with follow-up mammography, US-guided FNA appears to be efficacious in the management of patients with abnormal radiographic findings. It is quick, relatively inexpensive, and minimally invasive, and, in the presence of competent cytopathologists, should be the modality of choice.     

Screening for bone metastases: whole-body MRI using a 32-channel system versus dual-modality PET-CT

The diagnostic accuracy of screening for bone metastases was evaluated using whole-body magnetic resonance imaging (WB-MRI) compared with combined fluorodeoxyglucose (FDG) positron emission tomography (PET) and computed tomography (CT) (FDG-PET-CT). In a prospective, blinded study, 30 consecutive patients (18 female, 12 male; 24–76 years) with different oncological diseases and suspected skeletal metastases underwent FDG-PET-CT as well as WB-MRI with the use of parallel imaging (PAT). With a 32-channel scanner, coronal imaging of the entire body and sagittal imaging of the complete spine was performed using T1-weighted and short tau inversion recovery (STIR) sequences in combination. PET-CT was conducted using a low-dose CT for attenuation correction, a PET-emission scan and diagnostic contrast-enhanced CT scan covering the thorax, abdomen and pelvis. Two radiologists read the MRI scans, another radiologist in combination with a nuclear medicine physician read the PET-CT scans, each in consensus. The standard of reference was constituted by radiological follow-up within at least 6 months. In 28 patients, 102 malignant and 25 benign bone lesions were detected and confirmed. WB-MRI showed a sensitivity of 94% (96/102), PET-CT exams achieved 78% (79/102; P<0.001). Specificities were 76% (19/25) for WB-MRI and 80% (20/25) for PET-CT (P>0.05). Diagnostic accuracy was 91% (115/127) and 78% (99/127; P<0.001), respectively. Cut-off size for the detection of malignant bone lesions was 2 mm for WB-MRI and 5 mm for PET-CT. WB-MRI revealed ten additional bone metastases due to the larger field of view. In conclusion, WB-MRI and FDG-PET-CT are robust imaging modalities for a systemic screening for metastatic bone disease. PAT allows WB-MRI bone marrow screening at high spatial resolution and with a diagnostic accuracy superior to PET-CT.     

^18F-氟化钠PET和PET-CT诊断肺癌骨转移的对比研究

目的对比研究^18F-氟化钠（^18F-NaF）PET和PET-CT对肺癌骨转移诊断的准确性。方法34例初始诊断为肺癌的患者接受^18F-NaFPET-CT检查,对PET和PET-CT图像分别进行解释,发现的病变分为恶性、良性和不确定三种。骨转移的综合评价方法包括MRI（34例）、^18F-氟脱氧葡糖糖PET-CT（4例）、组织学活检（2例）和临床随访（6例）。结果按患者水平分析时,34例患者中的11例（32％）发生骨转移,其中,^18F-NaFPET—CT准确诊断所有患者的骨转移,无假阳性和假阴性,而^18F-NaFPET诊断真阳性8例、3例不能确定,^18F-NaFPET确诊的8例骨转移患者中的4例PET没有显示全部转移病变（假阴性和不确定病变）;按病变水平分析时,118个病变获得最终诊断,其中转移病变47个、良性病变71个,其中,^18F-NaFPET诊断真阳性27个、真阴性64个、不确定病变24个、假阴性1个、假阳性2个,而^18F-NaFPET-CT诊断真阳性46个、假阴性1个、真阴性71个。按患者水平分析,将不确定病变归为恶性时,^18F-NaFPET-CT的特异性高于^18F-NaFPET（100％vs78％,χ2=10．78,P〈0．05）,二者的灵敏度均为100％;将不确定病变归为良性时,^18F-NaFPET-CT诊断骨转移的灵敏度显著高于^18F-NaFPET（100％vs73％,r=6．41,P〈0．01）,二者特异度差异无显著性（100％vs96％,χ^2=2．03,P〉0．05）;按病变水平分析时,得到与患者水平分析相似结果。结论 ^18F-NaFPET-CT诊断肺癌骨转移的准确性优于^18F-NaFPET,PET—CT中的低剂量CT可进一步提高良、恶性病变的鉴别能力。     

Clinical significance and outcome of one or two rib lesions on bone scans in breast cancer patients without known metastases

The presence of one or two rib lesions on bone scans of post-treatment breast cancer patients without known metastases often makes clinical decision making problematic. The aim of this study was to identify skeletal metastasis predictors that might help the management of these patients. We recruited post-treatment breast cancer patients without overt metastases whose bone scans showed (1) one or two rib hot spots, or (2) one rib lesion and a concurrent bone abnormality. Their clinical and serial scintigraphic data were collected, reviewed and evaluated for correlations. After their first abnormal bone scans, 23 patients (11 of the 77 patients initially with one rib lesion (incidence, 14.3%), three of the 27 patients with two rib lesions (incidence, 11.1%), and nine of the 11 patients with one rib lesion plus a concurrent bone abnormality (incidence, 81.8%)) developed multiple bone metastases within 2 years of the initial rib lesions in all but one case. Univariate analyses revealed that a concurrent bone lesion other than the rib, direct tumour invasion to the chest wall or skin, and 10 or more lymph nodes involved were associated with increased risks of bone metastases whereas longer persistence of the rib lesions was associated with a lower risk. Multivariate proportional hazard analyses indicated that patients with a concurrent bone lesion other than the rib (relative risk (RR)=39.65; 95% confidence interval (CI)=8.13-193.28), 10 or more lymph nodes involved (RR=13.49; 95% CI=2.09-86.91), and no radiotherapy (RR=7.59; 95% CI=2.11-27.39) were more likely to have bone metastases, while those with longer persistence of the rib lesions (RR=0.92; 95% CI=0.84-0.98) and longer time interval between surgery and the rib lesion detection (RR=0.96; 95% CI=0.94-0.99) were less likely. We have identified clinical features applicable to risk stratification. High incidence of bone metastases was noted in patients with one rib lesion and a concurrent bone abnormality. Regular follow-up for 2 years after detection of rib lesions is recommended, especially for those with risk factors.     

Percutaneous radio-frequency ablation of liver metastases from breast cancer: initial experience in 24 patients.

PURPOSE: To evaluate the authors' initial experience in a consecutive series of 24 patients with breast cancer liver metastases treated with radio-frequency (RF) ablation. MATERIALS AND METHODS: Twenty-four consecutive patients with 64 metastases measuring 1.0--6.6 cm in diameter (mean, 1.9 cm) underwent ultrasonography-guided percutaneous RF ablation with 18-gauge, internally cooled electrodes. Treatment was performed with the patient under conscious sedation and analgesia or general anesthesia. A single lesion was treated in 16 patients, and multiple lesions were treated in eight patients. Follow-up with serial computed tomography ranged from 4 to 44 months (mean, 10 months; median, 19 months). RESULTS: Complete necrosis was achieved in 59 (92%) of 64 lesions. Among the 59 lesions, complete necrosis required a single treatment session in 58 lesions (92%) and two treatment sessions in one lesion (2%). In 14 (58%) of 24 patients, new metastases developed during follow-up. Ten (71%) of these 14 patients developed new liver metastases. Currently, 10 (63%) of 16 patients whose lesions were initially confined to the liver are free of disease. One patient died of progressive brain metastases. No major complications occurred. Two minor complications were observed. CONCLUSION: On the basis of preliminary study results, percutaneous RF ablation appears to be a simple, safe, and effective treatment for focal liver metastases in selected patients with breast cancer.     

Lung cancer detection with low-dose spiral computed tomography in chronic obstructive pulmonary disease patients

Purpose: To determine whether low-dose spiral computed tomography (LDCT) can improve the lung cancer detection rate in chronic obstructive pulmonary disease (COPD) subjects.

Material and Methods: From October 1999 to December 2003, 374 COPD patients underwent LDCT for lung carcinoma screening. All subjects with an abnormal baseline CT scan were followed with serial CT scans as part of our protocol. Follow-up was continued until the demonstration of no change over a minimum of 24 months, or resolution. Sputum samples were also obtained for cytological analysis.

Results: On the baseline spiral CT scan, 132 of 374 patients (35.2%) had at least one non-calcified nodule that required periodic follow-up with CT scans. The median follow-up time was 21 months (range 2-48 months). Of the 374 COPD subjects, nine patients with primary lung cancer (2.4%) were detected: six were squamous cell carcinomas, two were small-cell lung carcinomas (SCLC), and one was adenosquamous carcinoma. Three of the nine tumors were in stage IA, two in stage IIB, two in stage IIIA, and two were limited SCLC. Potentially curative pulmonary resection was performed in four patients, pulmonary lobectomy in three, and wedge excision in one. One subject with stage IA squamous cell carcinoma received radiotherapy, as pulmonary function was severely impaired. In addition, four patients underwent removal of benign lesions. Sputum was collected in 205 (54.8%) of 374 patients. There were 154 (75 %) metaplasia, 14 (6%) moderate dysplasia, and one (0.4%) malignant case.

Conclusion: LDCT increases early lung carcinoma detection rate in COPD patients, but pulmonary function impairment may reduce its benefit.     

18F-氟化钠PET和PET-CT诊断肺癌骨转移的对比研究

目的 对比研究18F-氟化钠(18F-NaF)PET和PET-CT对肺癌骨转移诊断的准确性.方法 34例初始诊断为肺癌的患者接受18F-NaF PET-CT检查,对PET和PET-CT图像分别进行解释,发现的病变分为恶性、良性和不确定三种.骨转移的综合评价方法包括MRI(34例)、18F-氟脱氧葡糖糖PET-CT(4例)、组织学活检(2例)和临床随访(6例).结果 按患者水平分析时,34例患者中的11例(32%)发生骨转移,其中,18F-NaF PET-CT准确诊断所有患者的骨转移,无假阳性和假阴性,而18F-NaF PET诊断真阳性8例、3例不能确定,18F-NaF PET确诊的8例骨转移患者中的4例PET没有显示全部转移病变(假阴性和不确定病变);按病变水平分析时,118个病变获得最终诊断,其中转移病变47个、良性病变71个,其中,18F-NaF PET诊断真阳性27个、真阴性64个、不确定病变24个、假阴性1个、假阳性2个,而18F-NaF PET-CT诊断真阳性46个、假阴性1个、真阴性71个.按患者水平分析,将不确定病变归为恶性时,18F-NaF PET-CT的特异性高于18F-NaF PET(100% vs 78%,χ2=10.78,P<0.05),二者的灵敏度均为100%;将不确定病变归为良性时,18F-NaF PET-CT诊断骨转移的灵敏度显著高于18F-NaF PET(100% vs 73%,χ2=6.41,P<0.01),二者特异度差异无显著性(100% vs 96%,χ2=2.03,P>0.05);按病变水平分析时,得到与患者水平分析相似结果.结论 18F-NaF PET-CT诊断肺癌骨转移的准确性优于18F-NaF PET,PET-CT中的低剂量CT可进一步提高良、恶性病变的鉴别能力.