18F-FDG PET显像在原发灶不明转移癌中的应用价值

目的 转移性肿瘤原发灶的定位对指导组织学诊断及选择治疗方式具有重要意义。本文对50例原发灶不明转移癌患者进行~(18)F-FDG PET全身显像,以评价其在探测原发灶中的价值。 方法 50例原发灶不明转移癌患者,男36例,女14例,其中颈部转移瘤18例,骨骼转移瘤15例,脑转移瘤12例,其他5例。所有患者均进行FDG PET全身显像,结果判断应用目测法和半定量分析方法(标准摄取值,SUV)。 结果 50例患者中,有32例PET可检出原发灶(64％),且经组织学或细胞学证实,其中肺癌17例,鼻咽癌9例,乳腺癌2例,卵巢癌、结肠癌、前列腺癌、甲状腺癌各1例。2例(4％)FDG PET呈假阳性,分别为子宮和结肠病变各1例。18例FDG PET显像原发灶不明者,经临床随访2～26个月,有2例发现原发灶,1例证实为前列腺癌,1例为粘液性胃癌。17例患者PET检出了其他部位的转移灶。 结论 PET一次检查可了解肿瘤原发灶及全身转移情况,包括骨骼及软组织的转移,对原发灶不明转移癌患者进行全身PET检查有助于原发灶的寻找,为临床制订治疗方案提供可靠依据。

Detection of unknown primary tumors using whole body FDG PET

Objective: To assess the usefulness of 2-fluorine-18]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) in locating occult primary lesions. Methods: 50 patients with varying heterogeneous metastases of unknown primary origin were referred for FDG PET. The locations of the known metastatic tumor manifestations were distributed as follows: cervical lymph nodes metastases (n=18), skeletal metastases (n=15), cerebral metastases (n=12), others (n=5). All patients underwent whole body ~(18)F-FDG PET imaging. The images were interpreted by visual inspection and semi-quantitative analysis (standardized uptake value, SUV). The patients had undergone conventional imaging within 2 weeks of FDG PET. Surgical, clinical and histopathologic findings were used to assess the performance of FDG PET. Results: FDG PET was able to detect the location of the primary tumor in 32/50 patients (64%). The primary tumors were proved by histopathologic results, and located in the lungs (n=17), the nasopharynx (n=9), the breast (n=2), the ovary (n=1), the colon(n=1), the prostate(n=1),the thyroid (n=1). FDG PET were proved false positive in 2 patients (4%), and the suspicious primary tumors were in uterus and colon respectively. During the clinical follow-up of 2 to 26 months, the primary tumor was found in only 2 patients (prostate cancer, gastric cancer). Conclusion: PET imaging allows identification of the primary site and metastatic lesions(including bone and soft tissue metastases) at a single examination. Whole body ~(18)F-FDG PET allows effective localization of the unknown primary site of origin and can contribute substantially to patient care.