原发性腹膜后肿瘤的

目的 观察原发性腹膜后肿瘤的¹⁸F-FDG PET/CT显像特征。方法 回顾性分析32例经病理证实的原发性腹膜后肿瘤¹⁸F-FDG PET/CT显像资料。观察不同病理类型肿瘤的¹⁸F-FDG PET/CT显像特征，测量肿瘤最大径及最大标准摄取值（SUV_max），比较良、恶性肿瘤最大径及SUV_max差异。结果 恶性肿瘤18例，17例形态不规则，14例边界不清，11例¹⁸F-FDG 摄取不均匀，2例可见远处转移；良性肿瘤14例，13例呈圆形或椭圆形，边界均清晰，11例¹⁸F-FDG摄取均匀，1例神经鞘瘤及1例畸胎瘤¹⁸F-FDG无摄取。恶性肿瘤SUV_max（11.93±7.01）明显高于良性肿瘤（3.66±2.20），差异有统计学意义（Z=-4.103，P<0.001）；恶性肿瘤与良性肿瘤最大径的差异亦有统计学意义（Z=-3.287，P=0.001）。结论 原发性腹膜后肿瘤的¹⁸F-FDG PET/CT表现具有一定特征，有助于临床诊断。

18F-FDG PET/CT manifestations of primary retroperitoneal tumors

Objective To observe the manifestations of primary retroperitoneal tumors on ¹⁸F-FDG PET/CT. Methods The data of ¹⁸F-FDG PET/CT scanning of 32 patients with primary retroperitoneal tumors confirmed by pathology were retrospectively analyzed. The manifestations on ¹⁸F-FDG PET/CT were observed, and the maximum diameter and SUV_max of tumors were measured. The maximum diameter and SUV_max of tumors between benign and malignant tumors were compared. Results Among 18 cases of malignant primary retroperitoneal tumors, appeared as irregular sharp in 17 cases, obscure boundary in 14 cases, and heterogeneous uptake of ¹⁸F-FDG in 11 cases, and 2 cases with distant metastasis. Among 14 cases of benign primary retroperitoneal tumors, appeared as round or ellipse in 13 cases,clear boundary in all cases, and homogeneity uptake of ¹⁸F-FDG in 11 cases. 1 case of schwannoma and 1 case of teratoma had no uptake of ¹⁸F-FDG. The SUV_max of malignant tumors (11.93±7.01) were higher than that of benign tumors (3.66±2.20) with statistical significance (Z=-4.103, P<0.001). And the difference of tumor maximum diameter between benign and malignant tumors was also statistically significative (Z=-3.287, P=0.001). Conclusion The ¹⁸F-FDG PET/CT manifestation of primary retroperitoneal tumors has certain characteristics which is helpful for clinical diagnosis.