Breast cancer staging in a single session: whole-body PET/CT mammography

Our objective was to compare the diagnostic accuracy of an all-in-one protocol of whole-body 18F-FDG PET/CT and integrated 18F-FDG PET/CT mammography with the diagnostic accuracy of a multimodality algorithm for initial breast cancer staging. METHODS: Forty women (mean age, 58.3 y; range, 30.8-78.4 y; SD, 12 y) with suspected breast cancer were included. For the primary tumor, we compared 18F-FDG PET/CT mammography versus MRI mammography; for axillary lymph node status, 18F-FDG PET/CT versus clinical investigation and ultrasound; and for distant metastases, 18F-FDG PET/CT versus a multimodality staging algorithm. Histopathology and clinical follow-up served as the standard of reference. The Fisher exact test evaluated the significance of differences (P < 0.05). Alterations in patient management caused by 18F-FDG PET/CT were documented. RESULTS: No significant differences were found in the detection rate of breast cancer lesions (18F-FDG PET/CT, 95%; MRI, 100%; P = 1). 18F-FDG PET/CT correctly classified lesion focality significantly more often than did MRI (18F-FDG PET/CT, 79%; MRI, 73%; P < 0.001). MRI correctly defined the T stage significantly more often than did 18F-FDG PET/CT (MRI, 77%; 18F-FDG PET/CT, 54%; P = 0.001). 18F-FDG PET/CT detected axillary lymph node metastases in 80% of cases; clinical investigation/ultrasound, in 70%. This difference was not statistically significant (P = 0.067). Distant metastases were detected with 18F-FDG PET/CT in 100% of cases, and the multimodality algorithm identified distant metastases in 70%. This difference was not statistically significant (P = 1). Three patients had extraaxillary lymph node metastases that were detected only by PET/CT (cervical, retroperitoneal, mediastinal/internal mammary group). 18F-FDG PET/CT changed patient management in 12.5% of cases. CONCLUSION: Our data suggest that a whole-body 18F-FDG PET/CT mammography protocol may be used for staging breast cancer in a single session. This initial assessment of the 18F-FDG PET/CT protocol indicates similar accuracy to MRI for the detection of breast cancer lesions. Although MRI seems to be more accurate when assessing the T stage of the tumor, 18F-FDG PET/CT seems able to more accurately define lesion focality. Although 18F-FDG PET/CT mammography was able to detect axillary lymph node metastases with a high sensitivity, this method cannot soon be expected to replace the combination of clinical examination, ultrasound, and sentinel lymph node biopsy for axillary assessment.     

Computed tomography enterography and 18F-FDG PET/CT features of primary signet ring cell carcinoma of the small bowel in a patient with Crohn's disease

We report a case of a primary signet ring cell carcinoma (PSRCC) of the small bowel in a patient with long-standing Crohn's disease, describing computed tomography (CT)-enterography (CTE) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT features of this rare tumor. CTE demonstrated submucosal thickening of a long ileal segment with preserved mural stratification. PET/CT examination showed increased 18F-FDG uptake in the affected ileal loop, hypermetabolic abdominal and mediastinal lymphadenopathies, and multiple hypermetabolic bone lesions. Iliac crest osteo-medullary biopsy revealed bone marrow infiltration by “signet ring” cells with intestinal differentiation. Double-balloon enteroscopy was used to obtain biopsies that confirmed the ileal origin of the PSRCC.     

18F-FDG PET/CT for staging of penile cancer.

The value of PET or PET/CT with (18)F-FDG for the staging of penile cancer has yet to be determined. The objective of this study was to investigate the pattern of (18)F-FDG uptake in the primary malignancy and its metastases and to determine the diagnostic value of (18)F-FDG PET/CT in the staging and restaging of penile cancer. METHODS: Thirteen patients (mean +/- SD age, 64 +/- 14.0 y) with suspected penile cancer or suspected recurrent disease were examined with a Gemini PET/CT system (200 MBq of (18)F-FDG). The reference standard was based on histopathologic findings obtained at biopsy or during surgery. RESULTS: Both the primary tumor and regional lymph node metastases exhibited a pattern of (18)F-FDG uptake typical for malignancy. Sensitivity in the detection of primary lesions was 75% (6/8), and specificity was 75% (3/4). On a per-patient basis, sensitivity in the detection of lymph node metastases was 80% (4/5), and specificity was 100% (8/8). On a nodal-group basis, PET/CT showed a sensitivity of 89% (8/9) in the detection of metastases in the superficial inguinal lymph node basins and a sensitivity of 100% (7/7) in the deep inguinal and obturator lymph node basins. The mean +/- SD maximum standardized uptake value for the 8 primary lesions was 5.3 +/- 3.7, and that for the 16 lymph node metastases was 4.6 +/- 2.0. CONCLUSION: According to our results, the main indication for (18)F-FDG PET in the primary staging or follow-up of penile cancer patients may be the prognostically crucial search for lymph node metastases. With the use of a PET/CT unit, the additional information provided by CT may be especially useful for planning surgery. Implementing (18)F-FDG PET and PET/CT in future staging algorithms may lead to a more precise and stage-appropriate therapeutic strategy. Furthermore, invasive procedures with a high morbidity rate, such as general bilateral lymphadenectomy, may be avoided.     

Successful Localization Using <Superscript>68</Superscript>Ga-DOTATOC PET/CT of a Phosphaturic Mesenchymal Tumor Causing Osteomalacia in a Patient with Concurrent Follicular Lymphoma

Diagnosing tumor-induced osteomalacia is often challenging because conventional imaging modalities may fail to locate the responsible tumor. This report describes the ability of ⁶⁸Ga-DOTATOC PET/CT to successfully distinguish between the responsible phosphaturic mesenchymal tumor and concurrent lymphoma lesions. A 52-year-old man with bone pain for several years was diagnosed with a vitamin D-resistant hypophosphatemic osteomalacia. Whole body ¹⁸F-FDG PET/CT revealed multiple enlarged hypermetabolic lymph nodes in his bilateral cervical, axillary, mediastinal, abdominal, pelvic, and inguinal regions. Core needle biopsy of the right cervical lymph node confirmed the diagnosis of follicular lymphoma. However, lymphoma was not considered the cause of osteomalacia. ⁶⁸Ga-DOTATOC PET/CT before chemotherapy showed a small nodule with intensely increased uptake in the right inguinal region, which was distinguished from the other enlarged lymph nodes. The nodule was surgically removed and histopathologically consistent with phosphaturic mesenchymal tumor. After surgery, the patient’s serum phosphorus and alkaline phosphatase levels normalized without nutritional supplement.     

Preoperative assessment of cervical lymph nodes in head and neck cancer with fluorine-18 fluorodeoxyglucose using a dual-head coincidence camera: a pilot study.

The aim of this study was to investigate whether in patients with head and neck cancer, staging is possible with fluorine-18 fluorodeoxyglucose (18F-FDG) using a dual-head positron emission tomography (PET) camera. Twenty patients (ten men, ten women; mean age: 60 years) were studied using 185 MBq (5 mCi) 18F-FDG. Two of these patients who were suspected of having recurrence in the neck were restaged 19 and 12 months, respectively, after the resection of the primary tumour. The images were visually analyzed and the results were correlated with computed tomography (CT) (n = 18), ultrasonography (n = 17) and pathological findings. With respect to the primary tumour, FDG dual-head PET and CT revealed a sensitivity of 100% and 59%, respectively (P < 0.001). In seven patients lymph node metastases were found in the neck specimen. Two of them had bilateral metastases. FDG dual-head PET correctly identified all nine pathological neck sides whereas CT and ultrasonography depicted eight of nine and seven of eight pathological sides, respectively. In three patients, false-positive FDG uptake was seen, which was due to a preceding biopsy in two cases. The sensitivity of FDG dual-head PET, CT and ultrasonography in the identification of pathological neck sides was 100%, 89% and 87%, respectively, and the specificity was 90%, 93% and 50%, respectively. With knowledge of the preceding biopsies, the specificity of FDG dual-head PET would have been 97%. The smallest lymph node metastasis detected by FDG dual-head PET that was missed by CT had a diameter of 0.6 cm. Measurement of 18F-FDG with a dual-head PET camera is very sensitive in the detection of primary head and neck cancers and accurate in the preoperative assessment of lymph node metastases. The results justify a prospective study on the identification of metastases in patients with head and neck cancer. In addition, it is justified to start a study on the detection of unknown primary tumours in patients with cervical metastases.     

Lymph node staging of gastric cancer using (18)F-FDG PET: a comparison study with CT.

This study was performed to compare (18)F-FDG PET with CT for the evaluation of primary tumors and lymph node metastases in gastric cancer. METHODS: Eighty-one patients (28 women and 53 men; mean age, 56.6 y; age range; 32-82 y) who had undergone radical (n = 74) or palliative (n = 7) gastrectomy and lymph node dissection for the management of gastric cancer were included. Preoperative (18)F-FDG PET and CT were reviewed retrospectively for primary tumors of the stomach and lymph node metastases. Any increased (18)F-FDG uptake exceeding that of the adjacent normal gastric wall was considered positive for the primary tumor. Lymph nodes were classified into 3 groups based on their anatomic sites. Because perigastric lymph nodes (N1) were often not clearly differentiated from primary tumors, N1 lymph node metastases were determined when possible. Lymph nodes were considered positive or negative on the basis of the group as a whole. Final conclusions for primary tumors and lymph node metastases were based on histopathologic specimens in all patients. RESULTS: There were 17 patients with early gastric cancer (EGC) and 64 patients with advanced gastric cancer (AGC). For primary tumors, both PET and CT showed a sensitivity of 47% (8/17) for EGC and 98% (63/64) for AGC. The sensitivity of CT for N1 disease was significantly higher than that of PET. (18)F-FDG PET had a sensitivity, specificity, and accuracy of 34% (11/32), 96% (47/49), and 72% (58/81), respectively, for N2 metastases, whereas the corresponding CT values were 44% (14/32), 86% (42/49), and 69% (56/81). For N3 metastases, PET and CT had the same sensitivity, specificity, and accuracy: 50% (3/6), 99% (74/75), and 95% (77/81), respectively. Overall, the sensitivity, specificity, and accuracy of (18)F-FDG PET were not significantly different from those of CT for primary tumors or for N2 and N3 metastases. CONCLUSION: (18)F-FDG PET is as accurate as CT for the detection of primary tumors of either EGC or AGC. The low sensitivities of PET and CT were insufficient to allow decision making on the extent of lymphadenectomy. In contrast, the high specificity of PET for N disease appeared valuable, and the presence of N disease on PET may have a clinically significant impact on the choice of initial therapy.     

Clinical role of (18)F-FDG PET for initial staging of patients with extrahepatic bile duct cancer

In extrahepatic bile duct cancer, preoperative evaluation is important because only surgical excision of all detectable tumours is associated with improvement in 5-year survival. However, morphological imaging techniques, including computed tomography (CT), are still insufficient for accurate staging. The purpose of this study was to assess the additional value, in relation to CT, of 2-[(18)F]fluoro-2-deoxy- D-glucose positron emission tomography ((18)F-FDG PET) for the evaluation of extrahepatic bile duct cancer. Thirty patients with extrahepatic bile duct cancer underwent both (18)F-FDG PET and CT for initial staging. The results of the two modalities for evaluation of primary tumours and regional lymph nodes were compared with the final diagnoses based on pathological or clinical findings. The primary tumours were interpreted as malignant on the basis of CT in 24 (80%) of the patients, while (18)F-FDG PET revealed increased (18)F-FDG uptake in 18 (60%) of them. On the other hand, (18)F-FDG PET showed focal accumulation of (18)F-FDG in the bile duct in three of the six patients with equivocal findings on CT. The sensitivity, specificity and accuracy of CT for regional lymph node metastases were 54%, 59% and 57%, while those of (18)F-FDG PET were 38%, 100% and 73%, respectively. The specificity of (18)F-FDG PET for regional lymph node metastases was significantly higher than that of CT ( P<0.01). Of 14 patients with N1 or N2 disease diagnosed by CT, only seven (50%) had a final diagnosis of regional lymph node metastasis. In these 14 patients, (18)F-FDG PET accurately evaluated the N component of the disease in 12 patients (86%). In conclusion, in the initial staging of patients with extrahepatic bile duct cancer, (18)F-FDG PET offers additional value in relation to CT in evaluating both the primary tumour and regional lymph nodes.     

Localization of dystonic muscles with 18F-FDG PET/CT in idiopathic cervical dystonia.

The purpose of this study was to investigate whether (18)F-FDG PET/CT is useful for localizing dystonic cervical muscles in patients with idiopathic cervical dystonia (ICD) by comparing disease severity before and disease severity after botulinum toxin (BT) injection into hypermetabolic muscles. METHODS: Six patients with ICD underwent (18)F-FDG PET/CT. Dystonic muscles suitable for BT injection therapy were defined as those showing diffusely increased (18)F-FDG uptake. RESULTS: Hypermetabolic cervical muscles were identified in all 6 patients. In 2 patients who underwent PET/CT both in a supine position and in a sitting position during (18)F-FDG uptake, abnormal hypermetabolic muscles were observed by PET/CT only when patients were in the sitting position with their heads and necks in the adopted abnormal involuntary posture. Symptoms were significantly improved in 4 patients who underwent BT injection therapy guided by PET/CT and who were clinically monitored. CONCLUSION: (18)F-FDG PET/CT is potentially useful for identifying dystonic cervical muscles for BT therapy in patients with ICD.     

18F-FDG PET/CT在原发灶不明的脑转移瘤中的诊断价值

目的 探讨18F-FDG PET/CT在查找原发灶不明的脑转移瘤中的价值。 方法 回顾性分析17例原发灶不明的脑转移瘤患者的全身18F-FDG PET/CT检查资料。 结果 17例患者均经活检确诊原发灶,准确率100%。原发性肺癌13例,占76%,其中有2例在第二次行PET/CT检查时才检出原发灶;原发性肝癌2例,占12%;原发性贲门癌1例,占6%;原发性升结肠癌1例,占6%。在检查到原发灶的基础上,18F-FDG PET/CT亦发现10例合并转移者,其中合并肺转移者2例、合并淋巴结转移者3例、合并骨转移者2例及合并其他部位转移者3例,共发现病灶61处;2例肝癌患者单发脑转移灶中均有脑卒中。 结论 18F-FDG PET/CT在查找原发灶不明的脑转移瘤原发灶中有重要价值,并为临床分期及治疗提供有利帮助。     

18F-FDG PET and CT/MRI in oral cavity squamous cell carcinoma: a prospective study of 124 patients with histologic correlation.

Accurate evaluation of primary tumors and cervical lymph node status of squamous cell carcinoma (SCC) of the oral cavity is important to treatment planning and prognosis prediction. In this prospective study, we evaluated the use of 18F-FDG PET, CT/MRI, and their visual correlation for the identification of primary tumors and cervical nodal metastases of SCC of the oral cavity with histologic correlation. METHODS: One hundred twenty-four patients with pathologically proven diagnoses of oral cavity SCC underwent 18F-FDG PET and CT/MRI within 2 wk before surgery. We interpreted 18F-FDG PET, CT/MRI, and visually correlated 18F-FDG PET and CT/MRI separately to assess the primary tumors and their regional lymph node status. We recorded lymph node metastases according to the neck level system of imaging-based nodal classification. Histopathologic analysis was used as the gold standard for assessment of the primary tumors and lymph node involvement. We analyzed differences in sensitivity and specificity among the imaging modalities using the McNemar test. The receiver-operating-characteristic (ROC) curve and calculation of the area under the curve were used to evaluate their discriminative power. RESULTS: The accuracy of 18F-FDG PET, CT/MRI, and their visual correlation for the identification of primary tumors was 98.4%, 87.1%, and 99.2%, respectively. The sensitivity of 18F-FDG PET for the identification of nodal metastases on a level-by-level basis was 22.1% higher than that of CT/MRI (74.7% vs. 52.6%, P < 0.001), whereas the specificity of 18F-FDG PET was 1.5% lower than that of CT/MRI (93.0% vs. 94.5%, P = 0.345). The sensitivity and specificity of the visual correlation of 18F-FDG PET and CT/MRI were 3.2% and 1.5% higher than those of 18F-FDG PET alone (77.9% vs. 74.7%, P = 0.25; 94.5% vs. 93.0%, P = 0.18, respectively). The area under the curve obtained from the ROC curve showed that 18F-FDG PET was significantly superior to CT/MRI for total nodal detection (0.896 vs. 0.801, P = 0.002), whereas the visual correlation of 18F-FDG PET and CT/MRI was modestly superior to 18F-FDG PET alone (0.913 vs. 0.896, P = 0.28). CONCLUSION: 18F-FDG PET is superior to CT/MRI in the detection of cervical status of oral cavity SCC. The sensitivity of 18F-FDG PET for the detection of cervical nodal metastasis on a level-by-level basis was significantly higher than that of CT/MRI, whereas their specificities appeared to be similar. Visual correlation of 18F-FDG PET and CT/MRI showed a trend of increased diagnostic accuracy over 18F-FDG PET alone but without a statistically significant difference, and its sensitivity was still not high enough to replace pathologic lymph node staging based on neck dissection.     

^18F-FDG PET／CT在胰腺癌诊断中的价值

目的评价^18F-脱氧葡萄糖（FDG）PET／CT鉴别诊断胰腺良恶性病变及检测淋巴结和（或）远处转移的价值。方法回顾性分析上海交通大学医学院附属仁济医院行^18F—FDGPET／CT检查的46例临床疑胰腺肿瘤患者的影像学检查资料和临床资料,其中胰腺癌患者26例,良性病变者20例,比较分析PET和CT的特征。结果当选择最大标准摄取值（SUVmax）=2．95为判断良恶性的界值时,对胰腺癌诊断的灵敏度是88．5％（23／26）,特异性是85．0％（17／20）。^18F—FDGPET／CT显像假阳性3例,假阴性3例。同时发现16例检查前未确定的肝、肺、骨及淋巴结转移患者。根据显像结果,11例患者治疗方案得以修正。结论根据现有资料分析,^18F—FDGPET／CT是鉴别诊断胰腺良恶性病变及检测胰腺癌患者淋巴结和（或）远处转移一种较好的方法。     

Detection of early recurrence with 18F-FDG PET in patients with cervical cancer.

This study investigated the feasibility of PET with (18)F-FDG to evaluate retrospectively early recurrence in patients with cervical cancer. METHODS: From September 1997 to March 2000, 249 patients with no evidence of cervical cancer after treatment were investigated with (18)F-FDG PET. (18)F-FDG PET scanning, beginning 50 min after injection of 370-555 MBq (18)F-FDG, was performed. (18)F-FDG uptake other than physiologic uptake was evaluated with the standardized uptake value and was analyzed by 2 observers who were unaware of CT or MRI data. CT or MRI and needle biopsies were performed to evaluate the positive lesions on (18)F-FDG PET, and all patients were monitored closely for 6 mo for recurrence. RESULTS: Of the 249 patients, 80 patients (32.1%) showed positive lesions with (18)F-FDG PET, and 28 patients (11.2%) were clinically or histologically confirmed as having recurrences. Eighty-two percent of recurrence was detected within 6-18 mo after diagnosis, and 89% of recurrence occurred in Fédération Internationale de Gynécologie et d'Obstétrique (FIGO) stage IIb and stage III patients. The sensitivity and specificity of (18)F-FDG PET for detection of early recurrence were 90.3% and 76.1%, respectively. The sensitivity of (18)F-FDG PET was high in mediastinal, hilar, and scalene lymph nodes, spine, and liver; however, the sensitivity was relatively low in lung, retrovesical lymph nodes, and paraaortic lymph nodes. Three false-negative cases were detected in lung, retrovesical lymph nodes, and paraaortic lymph nodes. CONCLUSION: (18)F-FDG PET was effective in detecting early recurrences in cervical cancer patients with no evidence of disease. (18)F-FDG PET may be a useful follow-up method for cervical cancer, thereby providing the patients with early opportunities for sophisticated treatments.     

Preoperative assessment of cervical lymph nodes in head and neck cancer with fluorine-18 fluorodeoxyglucose using a dual-head coincidence camera: a pilot study

The aim of this study was to investigate whether in patients with head and neck cancer, staging is possible with fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) using a dual-head positron emission tomography (PET) camera. Twenty patients (ten men, ten women; mean age: 60 years) were studied using 185 MBq (5 mCi) ¹⁸F-FDG. Two of these patients who were suspected of having recurrence in the neck were restaged 19 and 12 months, respectively, after the resection of the primary tumour. The images were visually analyzed and the results were correlated with computed tomography (CT) (n = 18), ultrasonography (n = 17) and pathological findings. With respect to the primary tumour, FDG dual-head PET and CT revealed a sensitivity of 100% and 59%, respectively (P<0.001). In seven patients lymph node metastases were found in the neck specimen. Two of them had bilateral metastases. FDG dual-head PET correctly identified all nine pathological neck sides whereas CT and ultrasonography depicted eight of nine and seven of eight pathological sides, respectively. In three patients, false-positive FDG uptake was seen, which was due to a preceding biopsy in two cases. The sensitivity of FDG dual-head PET, CT and ultrasonography in the identification of pathological neck sides was 100%, 89% and 87%, respectively, and the specificity was 90%, 93% and 50%, respectively. With knowledge of the preceding biopsies, the specificity of FDG dual-head PET would have been 97%. The smallest lymph node metastasis detected by FDG dual-head PET that was missed by CT had a diameter of 0.6 cm. Measurement of ¹⁸F-FDG with a dual-head PET camera is very sensitive in the detection of primary head and neck cancers and accurate in the preoperative assessment of lymph node metastases. The results justify a prospective study on the identification of metastases in patients with head and neck cancer. In addition, it is justified to start a study on the detection of unknown primary tumours in patients with cervical metastases. Received 19 October and in revised form 18 December 1998     

Multicentric Primary Angiosarcoma of Bone Mimicking Metastasis on 18F-FDG PET/CT in a Patient with a History of Sigmoid Colon Cancer: a Case Report

Primary angiosarcoma of the bone (PAB) is a rare and fatal high-grade malignant vascular bone tumor. We report a rare case of multicentric PAB mimicking bone metastasis in a 59-year-old female patient with a history of sigmoid colon cancer. This patient complained of lower back and pelvic pain and presented with multiple osteolytic bone lesions on plain radiography and pelvic computed tomography. First, bone metastasis of sigmoid colon cancer was suspected. However, on the ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) scan, the patient presented unusual multiple hypermetabolic osteolytic bone lesions involving contiguous bones of the lower half of the body. After bone biopsy, these lesions were confirmed to be multicentric PAB. To the best of our knowledge, this is the first case report of an ¹⁸F-FDG PET/CT scan in a patient with multicentric primary bone angiosarcoma.     

18F-FDG PET/CT显像在胃癌分期及治疗方案制定中的应用价值

目的探讨18F-FDG PET/CT显像在胃癌分期及治疗方案制定中的应用价值。方法回顾性分析46例临床疑诊胃癌患者的18F-FDG PET/CT图像,采用目测法和半定量法对患者PET/CT图像进行分析,即测定SUV_max与最大胃壁厚度（T_max）,以胃镜或手术后取得的病理结果作为“金标准”,评估18F-FDG PET/CT显像对病灶的诊断效能,并采用Pearson相关分析法分析SUV_max与T_max的相关性。结果18F-FDG PET/CT诊断原发病灶的灵敏度、特异度和准确率分别为94.4%、40.0%和82.6%;原发灶SUV_max与T_max呈正相关（r=0.922,P=0.001）;18F-FDG PET/CT诊断淋巴结转移及远处转移的灵敏度、特异度和准确率分别为76.9%、90.0%、82.6%和92.9%、96.9%、95.7%。结论18F-FDG PET/CT在检测胃癌的原发病灶、淋巴结转移灶和远处转移灶时有较高的特异度和灵敏度,在评估临床分期、指导临床制定正确的治疗方案中具有重要的应用价值。     

Peripheral bone involvement of intravascular large B-cell lymphoma on 99mTc-MDP bone scan and 18F-FDG PET/CT

A 64-year-old man was admitted for evaluation of recently developed anemia and bone pain. The bone scan showed diffusely active lesions in the peripheral bones, symmetrically. Interestingly, 18F-FDG PET/CT revealed the hypermetabolic changes in the peripheral bones as well as the internal organs. Biopsy of bone marrow confirmed the diagnosis of intravascular B-cell lymphoma. After the 3 cycles of R-CHOP chemotherapy, 18F-FDG PET/CT showed improvement of the previous hypermetabolic lesions, suggesting good response. Intravascular B-cell lymphoma is a rare and aggressive variant of diffuse large cell lymphoma characterized by proliferation of malignant cells within the vascular lumina.     

Evaluation of head and neck cancer with 18F-FDG PET: a comparison with conventional methods

The aim of this study was to evaluate the usefulness of 18F-FDG PET in the diagnosis and staging of primary and recurrent malignant head and neck tumours in comparison with conventional imaging methods [including ultrasonography, radiography, computed tomography (CT) and magnetic resonance imaging (MRI)], physical examination, panendoscopy and biopsies in clinical routine. A total of 54 patients (13 female, 41 male, age 61.3+/-12 years) were investigated retrospectively. Three groups were formed. In group I, 18F-FDG PET was performed in 15 patients to detect unknown primary cancers. In group II, 24 studies were obtained for preoperative staging of proven head and neck cancer. In group III, 18F-FDG PET was used in 15 patients to monitor tumour recurrence after radiotherapy and/or chemotherapy. In all patients, imaging was obtained at 70 min after the intravenous administration of 180 MBq 18F-FDG. In 11 of the 15 patients in group I, the primary cancer could be found with 18F-FDG, yielding a detection rate of 73.3%. In 4 of the 15 patients, CT findings were also suggestive of the primary cancer but were nonetheless equivocal. In these patients, 18F-FDG showed increased 18F-FDG uptake by the primary tumour, which was confirmed by histology. One patient had recurrence of breast carcinoma that could not be detected with 18F-FDG PET, but was detected by CT. In three cases, the primary cancer could not be found with any imaging method. Among the 24 patients in group II investigated for staging purposes, 18F-FDG PET detected a total of 13 local and three distant lymph node metastases, whereas the conventional imaging methods detected only nine local and one distant lymph node metastases. The results of 18F-FDG PET led to an upstaging in 5/24 (20.8%) patients. The conventional imaging methods were false positive in 5/24 (20.8%). There was one false positive result using 18F-FDG PET. Among the 15 patients of group III with suspected recurrence after radiotherapy and/or chemotherapy, 18F-FDG was true positive in 7/15 (46.6%) and true negative in 4/15 (26.6%). The conventional imaging methods were true positive in 5/15 (33.3%) and true negative in 4/15 (26.6%). One false negative (6.6%) and three false positive findings (20%) on 18F-FDG PET were due to inflamed tissue. The conventional imaging methods were false positive in three (20%) and false negative in three cases (20%). It is concluded that in comparison to conventional diagnostic methods, 18F-FDG PET provides additional and clinically relevant information in the detection of primary and metastatic carcinomas as well as in the early detection of recurrent or persistent head and neck cancer after radiotherapy and/or chemotherapy. 18F-FDG PET should therefore be performed early in clinical routine, usually before CT or MRI.     

18F-FDG PET/CT in the evaluation of POEMS syndrome

In POEMS syndrome the identification and biopsy of an osteosclerotic lesion or a lymph node typical of Castleman's disease (CD) is essential to establish the diagnosis and plan appropriate treatment. We report four patients in whom the localisation and identification of diagnostic bone lesions or lymphadenopathies were guided by fluorodeoxyglucose positron emission tomography integrated with computerised tomography (FDG PET/CT). FDG PET/CT identified bone lesions not detected with other techniques in one patient, and revealed hypermetabolic characteristics in bone lesions or adenopathies in the others, thus guiding the diagnostic biopsy in those with hypermetabolism. In conclusion, FDG PET/CT may be useful in detecting and selecting bone lesions and lymph nodes for biopsy in patients with suspected POEMS syndrome.     

18F-FDG PET/CT在寻找不明原发灶肿瘤患者原发灶中的价值

目的 探讨18F-FDG PET/CT在诊断不明原发灶肿瘤(CUP)患者原发灶中的价值.资料与方法 36例CUP患者行PET/CT检查拟寻找原发灶,根据转移灶部位分为淋巴结转移组(8例)、肝转移组(9例)、骨转移组(12例)及恶性胸腹水组(7例),比较18F-FDG PET/CT诊断淋巴结转移组与非淋巴结转移组CUP患者原发灶的灵敏度.结果 18F-FDG PET/CT寻找CUP原发灶的灵敏度为63.9％ (23/36),PET/CT诊断淋巴结转移组、肝转移组、骨转移组及恶性胸腹水组患者原发灶的灵敏度分别为87.5％ (7/8)、55.6％ (5/9)、58.3％(7/12)、57.1％ (4/7).18F-FDG PET/CT对淋巴结转移组原发灶的确诊率[87.5％(7/8)]显著高于非淋巴结转移组[57.1％( 16/28)],差异有统计学意义(P＜0.05).结论 18F-FDG PET/CT诊断CUP患者原发灶灵敏度较高,尤其适用于发生淋巴结转移的CUP患者.     

CT及18F-FDGPET/CT诊断食管癌术前淋巴结转移及N分期对比研究

目的 研究CT及18F-氟脱氧葡萄糖(FDG) PET/CT术前诊断食管癌淋巴结转移及确定N分期的价值.资料与方法 连续随机选择经食管镜或胃镜证实、拟行手术治疗、能够耐受手术的47例食管癌患者,术前1周内行CT及18F-FDG PET/CT检查,以术后病理为“金标准”,比较CT及18F-FDG PET/CT诊断食管癌淋巴结转移及N分期的敏感性、特异性、准确性、阳性预测值及阴性预测值.结果 31例存在淋巴结转移,共切除并分离淋巴结387枚(209组),其中65枚(46组)发现转移.CT诊断淋巴结转移的敏感性、特异性、准确性、阳性预测值、阴性预测值分别为53.8％、92.8％、86.3％、60.3％和90.9％;18F-FDG PET/CT分别为89.2％、93.8％、93.0％、74.4％和97.7％.PET/CT诊断淋巴结转移的敏感性、准确性及阴性预测值均显著高于CT,差异有统计学意义(P＜0.05),特异性及阳性预测值差异无统计学意义(P＞0.05).CT及18F-FDG PET/CT确定淋巴结分期的准确率分别为74.5％和91.5％,差异有统计学意义(P＜0.05).伴淋巴结转移的食管癌原发灶最大标准摄取值(SUVmax)为( 14.899±3.770),而无淋巴结转移者为(9.427±2.854).结论 18F-FDGPET/CT术前诊断食管癌淋巴结转移及确定N分期优于CT;食管癌原发灶SUVmax在一定程度上可以反映淋巴结转移情况.