18F-FDG PET显像在原发不明转移癌中的诊断价值

目的：探讨18F－脱氧葡萄糖（FDG）PET显像在原发不明转移癌中的诊断价值。方法：23例原发灶不明转移癌患者，进行18F－FDG PET显像，并与临床随访，活组织检查和手术病理结果相对照。结果：23例患者中18F－FDG PET发现可凝原发灶10例，其中8例病理结果证实为原发灶，1例经长期随访证实为原发灶，1例病理结果为阴性，18F－FDG PET对原发灶检出率为39％，18F－FDG PET全身显像共检出淋巴结和远处转移灶16个，CT和（或）MRI只检出9个，13例18F－FDG PET检查未确定原发灶者，随访3个月－1年，死亡4例，9例18F－FDG PET检查确定原发灶者，随访2个月－1年，死亡1例。结论：18F－FDG PET显像对原发灶不明转移癌原发灶的诊断，淋巴结和远处转移的分期，治疗方案的制定以及预后判断均有一定的临床价值。     

18F-FDG PET detection of unknown primary malignancy in dermatomyositis

Dermatomyositis is an inflammatory myopathy that has an association with malignancy in adults. We present a patient who initially presented with adenopathy and progressive muscular weakness and was diagnosed with dermatomyositis and lung carcinoma on further investigation. Whole-body PET/CT scan revealed diffuse proximal muscle hypermetabolism representing the inflammatory nature of dermatomyositis, and an intensely FDG-avid primary right lower lung small cell lung carcinoma and metastatic thoracic lymphadenopathy. PET/CT imaging may offer an "all-in-one" procedure as an alternative to other diagnostic procedures, reducing the number of unnecessary investigations in patients presenting with paraneoplastic syndromes searching for underlying malignancy.     

FDG PET detection of unknown primary tumors.

The management of patients presenting with metastases of unknown primary origin remains a clinical challenge despite a large variety of imaging modalities. The aim of this study was to evaluate FDG PET in detecting the sites of primary cancer in these patients. METHODS: Fifty-three patients with metastatic cervical adenopathy (n = 44) or extracervical metastases (n = 9) of unknown primary origin were included after extensive but inconclusive conventional diagnostic work-up. Patients received 370 MBq FDG (10 mCi) intravenously, and whole-body images were acquired at 60 min after injection. Clinical, surgical, and histopathologic findings and complete correlative imaging were used to assess the results. RESULTS: In 27 of 53 patients FDG PET showed focal tracer accumulations corresponding to potential primary tumor sites located in the lungs (n = 12), the palatine tonsil (n = 5), the salivary glands (n = 2), the nasopharynx (n = 1), the oropharynx (n = 3), the maxillary sinus (n = 1), and the larynx (n = 1). Moreover, in 2 patients FDG PET revealed lesions suspected to be tumors in the breast and the ileocolonic area. In 20 (37.8%) of these 53 patients FDG PET was true-positive, identifying the primary tumor in the lungs (n = 10), the head and neck region (n = 8), the breast (n = 1), and the ileocolonic area (n = 1). In 6 of 27 patients FDG PET was false-positive, predominantly identifying suspicious areas in the palatine tonsil (n = 3). One patient denied further diagnostic work-up after PET; thus, positive PET could not be evaluated. In 26 of 53 patients PET did not reveal lesions suspected to be the primary. However, primary tumors were not found in these patients at clinical follow-up. CONCLUSION: FDG PET is a valuable diagnostic tool in patients with cancer of unknown primary because it imaged unknown primary tumors in about one third of all patients investigated. In addition, FDG PET assists in both guiding biopsies for histologic evaluation and selecting the appropriate treatment protocols for these patients.     

Meta-analysis of the performance of 18F-FDG PET in cutaneous melanoma

Introduction

The aim of this study was to perform a systematic review of the literature to evaluate the accuracy of FDG-PET in staging and restaging of cutaneous melanoma.

Methods

Systematic methods were used to identify, select, and evaluate the methodologic quality of the studies as well as to summarize the overall findings of sensitivity and specificity. The search strategy consisted of identifying studies published between 2000 and 2006. Inclusion criteria were studies that evaluated the diagnostic performance of FDG-PET in staging/restaging of cutaneous melanoma. The results were compared and pooled with a meta-analysis published previously that included studies published until 1999. The meta-analysis included 95% confidence intervals (CI) of sensitivity, specificity, likelihood-ratio (LR), and diagnostic-odds-ratio (DOR).

Results

The quantitative meta-analysis included 24 studies that were analysed in two groups: eight studies were included only in the regional staging analysis (group I), 13 studies were included only in the detection of distant metastases analysis (group II), and three studies were included in both analyses. Compliance with the methodologic-quality criteria was acceptable. We analysed the results of data presented in patients, lesions, basins, lymph-nodes, areas, and scans. Regarding the performance of FDG-PET in the detection of metastases, the pooled studies presented homogeneity for the negative-LR (0.15; 95% CI, 0.10–0.22) when analyzing lesions. When analyzing scans, there was global homogeneity for specificity (0.86; 95% CI, 0.77–0.92), positive-LR (5.86; 95% CI, 3.64–9.43), and DOR (37.89; 95% CI, 15.80–90.86). The pooled studies presented heterogeneity for the other items analysed. Regarding the detection of regional metastases, when analyzing lymph-nodes there was global homogeneity for specificity (0.99; 95% CI, 0.97–0.99; P?=?0.101). The meta-regression evidenced that the variable that most influenced the DOR of the different studies and that can explain the heterogeneity was the year of publication; this may be related to the evolution of PET technology and an improvement of sensitivity/specificity.

Conclusion

FDG-PET is not useful in the evaluation of regional metastases, as it does not detect microscopic disease. However, FDG-PET could be useful in the detection of distant metastases, and could suggest its utility in the management of patients with cutaneous melanoma.     

18F-FDG PET/CT in the assessment of carcinoma of unknown primary origin

PURPOSE: Metastatic cancers of unknown primary origin are characterised by a poor prognosis, with a survival rate from diagnosis of approximately 12 months. Conventional radiological imaging allows detection of 20%-27% of primary cancers, whereas the detection rate with positron emission tomography (PET) is 24%-40%. The aim of this study was to assess the role of 18F-fluorodeoxyglucose (FDG) PET/computed tomography (CT) in the identification of occult primary cancers. MATERIALS AND METHODS: The study population consisted of 38 consecutive patients with histologically proven metastatic disease and negative or nonconclusive conventional diagnostic procedures. All patients were studied by 18F-FDG PET performed according to the standard procedure (6 h of fasting, intravenous injection of 370 MBq 18F-FDG, and image acquisition with a PET/CT scanner for 4 min per bed position). RESULTS: 18F-FDG-PET/CT detected the occult primary cancer in 20 cases (53%), showing higher sensitivity than that reported for any other imaging modality, including PET. CONCLUSIONS: The encouraging results, if validated by larger series, support the use of PET/CT in patients with carcinoma of unknown primary origin and negative conventional imaging results.     

18F-FDG PET/CT在不明原发灶肿瘤中的临床应用价值

目的探讨18F-FDG PET/CT全身显像在不明原发灶肿瘤（CUP）诊断中的临床应用价值。方法回顾分析46例于2015年2月至2016年6月在我院行常规检查未能发现肿瘤原发灶而进一步行18F-FDG PET/CT全身显像查找肿瘤原发灶的转移性肿瘤患者的资料。PET/CT图像分析采用视觉及半定量分析方法。通过病理活检和（或）临床综合诊断、临床随访对结果进行评价。结果46例患者中,18F-FDG PET/CT显像找到原发肿瘤33例,均经过病理活检及临床随访证实;13例未发现原发病灶。18F-FDG PET/CT对不明肿瘤原发灶的检出率为71.7%（33/46）,其中阳性患者中淋巴瘤3例、胃癌2例、食管癌4例、卵巢癌3例、肺癌14例、肝癌2例、尿路上皮癌1例、鼻咽癌2例、多发性骨髓瘤1例、降结肠癌1例。转移方式主要有淋巴结转移32例、骨转移20例、肝转移13例、肺转移9例、胸膜腹膜转移5例、肾上腺转移3例、脑转移4例、皮下转移3例、心包膜转移1例。结论18F-FDG PET/CT全身显像对CUP的检出率显著优于一般常规检查,对临床指导治疗有着重要意义。     

18F-FDG符合线路显像在不明原发灶肿瘤中的临床价值

目的评价^18F-脱氧葡萄糖(FDG)符合线路显像在不明原发灶肿瘤(UPT)中的临床价值。方法UPT患者36例，在^18F-FDG符合线路显像后4周内进行常规影像学检查。结果^18F-FDG符合线路显像对原发灶的检出灵敏度为42％(15／36例)；1例原发灶仅被^18F-FDG显像发现，3例首先被^18F-FDG显像发现，后在^18F-FDG显像结果的提示下被其他影像学检查发现，11例同时分别被^18F-FDG显像和常规影像学检查发现；14％(5／36例)患者因找到原发灶而改变了治疗方案；53％(19／36例)患者发现新的转移灶。结论^18F-FDG符合线路显像是寻找UPT原发灶的一种有效方法，并可同时评价患者的全身转移情况，可为选择最佳治疗方案和预后评价提供依据。     

18F-FDG PET and PET/CT in fever of unknown origin.

Fever of unknown origin (FUO) was originally defined as recurrent fever of 38.3 degrees C or higher, lasting 2-3 wk or longer, and undiagnosed after 1 wk of hospital evaluation. The last criterion has undergone modification and is now generally interpreted as no diagnosis after appropriate inpatient or outpatient evaluation. The 3 major categories that account for most FUOs are infections, malignancies, and noninfectious inflammatory diseases. The diagnostic approach in FUO includes repeated physical investigations and thorough history-taking combined with standardized laboratory tests and simple imaging procedures. Nevertheless, there is a need for more complex or invasive techniques if this strategy fails. This review describes the impact of (18)F-FDG PET in the diagnostic work-up of FUO. (18)F-FDG accumulates in malignant tissues but also at the sites of infection and inflammation and in autoimmune and granulomatous diseases by the overexpression of distinct facultative glucose transporter (GLUT) isotypes (mainly GLUT-1 and GLUT-3) and by an overproduction of glycolytic enzymes in cancer cells and inflammatory cells. The limited data of prospective studies indicate that (18)F-FDG PET has the potential to play a central role as a second-line procedure in the management of patients with FUO. In these studies, the PET scan contributed to the final diagnosis in 25%-69% of the patients. In the category of infectious diseases, a diagnosis of focal abdominal, thoracic, or soft-tissue infection, as well as chronic osteomyelitis, can be made with a high degree of certainty. Negative findings on (18)F-FDG PET essentially rule out orthopedic prosthetic infections. In patients with noninfectious inflammatory diseases, (18)F-FDG PET is of importance in the diagnosis of large-vessel vasculitis and seems to be useful in the visualization of other diseases, such as inflammatory bowel disease, sarcoidosis, and painless subacute thyroiditis. In patients with tumor fever, diseases commonly detected by (18)F-FDG PET include Hodgkin's disease and aggressive non-Hodgkin's lymphoma but also colorectal cancer and sarcoma. (18)F-FDG PET has the potential to replace other imaging techniques in the evaluation of patients with FUO. Compared with labeled white blood cells, (18)F-FDG PET allows diagnosis of a wider spectrum of diseases. Compared with (67)Ga-citrate scanning, (18)F-FDG PET seems to be more sensitive. It is expected that PET/CT technology will further improve the diagnostic impact of (18)F-FDG PET in the context of FUO, as already shown in the oncologic context, mainly by improving the specificity of the method.     

18F-FDG PET detection of colonic adenomas.

The adenomatous polyp of the colon is clinically important as a precursor of colonic cancer. The aim of this preliminary study was to evaluate the potential usefulness of (18)F-FDG PET for detecting adenomatous polyps of the colon. METHODS: We performed a retrospective study of 110 subjects who underwent both PET study and total colonoscopy. On nonattenuation-corrected PET images, focal distinct FDG accumulation along the large intestine was considered a positive finding, and the PET results were compared with colonoscopic findings. Histology and adenoma size were determined by polypectomy. RESULTS: Fifty-nine adenomatous polyps, 5-30 mm in size, were found in 30 subjects by total colonoscopy. PET findings were positive for 14 of the 59 adenomas (24%). The positivity rate for PET images rose with the increase in size of the adenomas; it was 90% in adenomas (9/10) that were > or =13 mm. The overall false-positive rate was 5.5% (6/110 subjects). CONCLUSION: Increased glucose metabolism is observed in colonic adenomas, and detectability with PET increases with the increase in adenoma size. Adenomas are premalignant lesions, and it is important to realize that colonic adenomas may be found incidentally during an FDG PET study.     

18 F-FDG PET/CT显像探测原发肿瘤病灶的临床价值

目的探讨^18F-脱氧葡萄糖(FDG)PET/CT显像寻找原发肿瘤病灶的价值。方法对临床诊断转移瘤患者31例行唧CT显像，将其诊断结果与手术、活组织检查及临床随访结果对照。结果29例患者唧CT显像准确显示其原发灶，分别为结、直肠癌7例，肺癌13例，甲状腺癌3例，子宫恶性肿瘤4例，胰腺癌和鼻咽癌各1例。1例PET/CT检查未能确定其原发灶。另1例临床诊断为肾上腺转移瘤的患者，PET/CT显像为良性肿瘤，经CT动态增强检查及实验室检查证实。结论PET／CT显像对寻找转移瘤原发灶有重要价值。     

18F-FDG PET/CT对原发不明颈部淋巴结转移癌患者原发灶检出的价值

目的 探讨18F-FDG PET/CT在原发不明颈部淋巴结转移癌患者原发灶检出中的临床应用价值.方法 回顾性分析2007年至2012年间因颈部淋巴结细针穿刺活组织检查提示转移但原发不明而行18F-FDG PET/CT检查的患者78例,其中男48例,女30例,平均年龄(56.4±14.7)岁.在PET/CT图像上勾画ROI并计算SUVmax.将淋巴结分为Ⅰ～Ⅵ区、咽后区及锁骨上区,取淋巴结短径为其大小.患者均经病理、随访确诊.观察肿瘤原发灶部位、病理类型及转移淋巴结分布、大小及SUVmax.采用单因素方差分析及直线相关分析分析数据.结果 78例患者中,恶性75例,良性3例(手术切除后病理检查).56例患者由PET/CT检出原发灶,检出率为71.8％(56/78).其中头颈部肿瘤占57.1％(32/56),对应转移淋巴结多分布于Ⅱ、Ⅲ、Ⅳ区(90.6％,29/32);体部肿瘤占42.9％(24/56),对应转移淋巴结多分布于锁骨上区(95.8％,23/24).不同原发部位及不同病理类型的颈部转移淋巴结大小和SUVmax差异均无统计学意义(F=0.037～ 2.413,均P＞O.05).结论 18F-FDGPET/CT有利于判断原发不明肿瘤的大致部位,并了解全身病灶分布.     

FDG PET在肝脏恶性肿瘤诊断中的应用

目的　评价PET诊断恶性肝肿瘤的价值及其局限性。方法　肝内良性占位病变患者10例 ,其中肝囊肿 6例 ,肝血管瘤 4例 ;肝内恶性病变患者 2 8例 ,其中肝细胞肝癌 (HCC) 13例 ,胆管细胞癌 (CCC) 1例 ,转移性肝癌 14例。按体重注入 5 .5 5MBq/kg18F 脱氧葡萄糖 (FDG) ,使用SiemensE CATEXACTHR+ PET仪采集和重建图像。根据FDG摄取将病灶分为 3种类型 ,A型 :病变部位摄取高于周围正常组织 ;B型 :与周围组织相近 ;C型 :低于周围组织或无摄取。结果　 9例HCC和 1例CCC为A型 ,标准摄取值 (SUV)为 3 0 2± 1 33。 3例HCC为B型 ,1例为C型。 14例转移性肝癌PET共发现转移灶 19个。结论　FDGPET可对肝内病灶进行定位、定性及转移的早期诊断 ,但应警惕HCC显像的特殊性 ,以免误诊或漏诊。     

^18F-FDG PET在原发性肾上腺淋巴瘤中的作用

目的探讨^18F—FDGPET（PET／CT）在原发性肾上腺淋巴瘤（PAL）中的作用。方法回顾性分析2005年10月至2009年8月确诊为PAL的3例患者。3例均为老年男性,双侧性NHL,治疗前均行超声、CT及PET（PET／CT）检查,并有组织病理学诊断资料。采用利妥昔单抗（rituximab）与环磷酰胺（cyclophosphamide）、表阿霉素（doxorubicin）、长春新碱（vincristine）、泼尼松（prednisone）组合（R—CHOP）方案化疗。治疗后1例进行了PET／CT的随访复查。^18F—FDGPET显像获得病灶SUVmax及与肝SUVmax的比值。结果3例均为双侧性弥漫大B细胞型PAL,骨髓穿刺阴性,R-CHOP方案化疗后,例1通过4次^18F—FDGPET复查随访、指导治疗,已存活1年7个月;例2伴有肾上腺皮质功能低下,6个月后死亡;例3年龄大（77岁）,病情重,手术部分切除后化疗,12个月后死亡。结论PAL虽然恶性程度极高,但如能早期诊断,并进行^18F—FDGPET疗效监测、修正治疗方案,可延长患者生存期。     

骨骼和软组织肿瘤18F-FDG PET的应用进展

18F-FDG(18F-氟代脱氧葡萄糖)PET在肿瘤学领域已经得到了深入研究和广泛应用,尽管有关骨与软组织肿瘤的研究报告相对较少,但是近年来陆续发表的有关文献内容已涉及骨与软组织肿瘤病变良恶性鉴别、肿瘤恶性程度判断、治疗反应监测、肿瘤复发评价和骨转移肿瘤探测等诸多方面.     

18F-FDG PET显像在原发性胃癌中的应用

目的　探讨1 8F 脱氧葡萄糖 (FDG)PET显像在原发性胃癌中的应用价值。方法　 2 2例经组织病理学证实的原发性胃癌患者行1 8F FDGPET显像。图像分析采用视觉及半定量方法 [标准摄取值 (SUV) ],其中 2 1例与近期CT结果比较。结果　①PET检出原发性胃癌的灵敏度为 91% (2 0 2 2例 ) ,2例假阴性均为印戒细胞癌 ,原发肿瘤直径 <1cm (T1 期 )。② 17例手术患者中 ,胃局部淋巴结转移 10例 ,PET检出 6例 ,其灵敏度、特异性和准确性分别为 6 0 %、10 0 %和 75 % ,CT仅检出 1例。③PET检出远处转移 9例 ,CT仅检出 5例。结论　1 8F FDGPET诊断原发性胃癌较为灵敏 ,检出胃癌局部淋巴结及远处转移可能优于CT。     

18F-FDG PET/CT的特点及其在肿瘤诊断中的应用

最近几年,具有高性能PET和CT的同机PET/CT已投入临床,其在肿瘤学中的应用呈迅速增长之势.加入高档CT的PET较之传统的PET在技术和临床方面具有明显优势.CT扫描一方面为PET提供了快速、准确的衰减校正数据,大大缩短采集时间,另一方面为PET图像提供了精确的解剖定位,使结果更加肯定,但引入CT的PET扫描也带来了一些技术上的新问题.PET/CT在头颈、腹盆肿瘤具有明显优势,即使在生理运动影响较大的胸部也取得了满意的效果.初步临床研究表明,PET/CT较之单独CT或PET在临床肿瘤学中具有明显优势,PET/CT融合显像对肿瘤患者和临床医生具有越来越重要的价值.     

Imaging proliferation in lung tumors with PET: 18F-FLT versus 18F-FDG.

Recently, the thymidine analog 3'-deoxy-3'-(18)F-fluorothymidine (FLT) was suggested for imaging tumoral proliferation. In this prospective study, we examined whether (18)F-FLT better determines proliferative activity in newly diagnosed lung nodules than does (18)F-FDG. METHODS: Twenty-six patients with pulmonary nodules on chest CT were examined with PET and the tracers (18)F-FDG and (18)F-FLT. Tumoral uptake was determined by calculation of standardized uptake value (SUV). Within 2 wk, patients underwent resective surgery or had core biopsy. Proliferative activity was estimated by counting nuclei stained with the Ki-67-specific monoclonal antibody MIB-1 per total number of nuclei in representative tissue specimens. The correlation between the percentage of proliferating cells and the SUVs for (18)F-FLT and (18)F-FDG was determined using linear regression analysis. RESULTS: Eighteen patients had malignant tumors (13 with non-small cell lung cancer [NSCLC], 1 with small cell lung cancer, and 4 with pulmonary metastases from extrapulmonary tumors); 8 had benign lesions. In all visible lesions, mean (18)F-FDG uptake was 4.1 (median, 4.4; SD, 3.0; range, 1.0-10.6), and mean (18)F-FLT uptake was 1.8 (median, 1.2; SD, 2.0; range, 0.8-6.4). Statistical analysis revealed a significantly higher uptake of (18)F-FDG than of (18)F-FLT (Mann-Whitney U test, P < 0.05). (18)F-FLT SUV correlated better with proliferation index (P < 0.0001; r = 0.92) than did (18)F-FDG SUV (P < 0.001; r = 0.59). With the exception of 1 carcinoma in situ, all malignant tumors showed increased (18)F-FDG PET uptake. (18)F-FLT PET was false-negative in the carcinoma in situ, in another NSCLC with a low proliferation index, and in a patient with lung metastases from colorectal cancer. Increased (18)F-FLT uptake was related exclusively to malignant tumors. By contrast, (18)F-FDG PET was false-positive in 4 of 8 patients with benign lesions. CONCLUSION: (18)F-FLT uptake correlates better with proliferation of lung tumors than does uptake of (18)F-FDG and might be more useful as a selective biomarker for tumor proliferation.     

18F-FDG PET/CT全身显像在原发灶不明转移癌中的临床应用

目的 探讨18F-脱氧葡萄糖(FDG)PET/CT全身显像在原发灶不明转移癌(CUP)诊断中的临床应用价值.方法 回顾性分析2006年1月至2007年6月2589例18F-FDG PET/CT显像患者中169例CUP患者的显像结果,通过分析病历记录、病理检查结果及临床随访确定最终原发灶诊断结果.结果 169例CUP患者中19例失访,150例有完整资料.70例成功探测到原发灶,总检出率为46.7%(70/150),其中52例得到病理检查证实,18例为临床诊断;肺癌38例,占54.3%,鼻咽癌8例,占11.4%,消化系统肿瘤13例,占18.6%,其他肿瘤11例,占15.7%.3例临床怀疑转移瘤,18F-FDG PET/CT未见明显恶性征象,经随访证实为良性病变.6例PET/CT诊断错误.15例患者没有确诊.56例未探测到原发灶,其中3例在随访过程中得到确诊,分别为鼻咽癌、膀胱癌、食管癌各1例.结论 18F-FDG PET/CT全身显像对诊断CUP具有重要临床价值.