前纵隔肿瘤18F-FDG PET/CT显像特征

目的 观察前纵隔肿瘤¹⁸F-FDG PET/CT显像特征。方法 回顾性分析28例经病理证实的前纵隔肿瘤患者的¹⁸F-FDG PET/CT资料。28例中，侵袭性胸腺瘤6例，胸腺癌8例，淋巴瘤12例，精原细胞瘤2例。观察不同肿瘤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），比较侵袭性胸腺瘤、胸腺癌及淋巴瘤患者肿瘤最大径及SUV_max差异。结果 侵袭性胸腺瘤、胸腺癌及精原细胞瘤¹⁸F-FDG PET/CT见前纵隔内形态不规则、密度不均匀软组织肿物。淋巴瘤¹⁸F-FDG PET/CT见前纵隔内多个结节融合成团块状肿物，密度均匀。侵袭性胸腺瘤、胸腺癌和淋巴瘤间肿瘤最大径差异无统计学意义（P=0.746）；胸腺癌和淋巴瘤SUV_max（11.54±3.79、14.11±4.34）高于侵袭性胸腺瘤（4.87±0.38），差异均有统计学意义（P=0.003、0.001），胸腺癌与淋巴瘤SUV_max差异无统计学意义（P=0.189）。结论 前纵隔肿瘤的¹⁸F-FDG PET/CT表现具有一定特征，有助于临床诊断。

Features of anterior mediastinal tumors in 18F-FDG PET/CT imaging

Objective To observe the features of anterior mediastinal tumors in ¹⁸F-FDG PET/CT imaging. Methods Data of ¹⁸F-FDG PET/CT scanning for 28 patients, including 6 of invasive thymoma, 8 of thymic carcinoma, 12 of lymphoma and 2 of seminoma confirmed by pathology were retrospectively analyzed. The features of ¹⁸F-FDG PET/CT were observed, then the maximum diameter and ¹⁸F-FDG uptake of all the tumors were measured and compared among invasive thymoma, thymic carcinoma and lymphoma. Results ¹⁸F-FDG PET/CT of invasive thymoma, thymic carcinoma and seminoma showed irregular tumors with heterogeneous density. ¹⁸F-FDG PET/CT of lymphoma showed crumb tumors mixed by several nodes with homogeneous density. There was no difference of maximum diameter of tumor among invasive thymoma, thymic carcinoma and lymphoma (P=0.746). The maximun of standardized uptake value (SUV_max) of thymic carcinoma (11.54±3.79) and lymphoma (14.11±4.34) were higher than that of invasive thymoma (4.87±0.38, P=0.003, 0.001), while no difference was found between thymic carcinoma and lymphoma (P=0.189). Conclusion ¹⁸F-FDG PET/CT features of anterior mediastinal tumors have certain characteristics, which are helpful to clinical diagnosis.