鉴别多房囊性肾细胞癌的主要CT征象及临界值

The main CT findings and its cut-off value to differentiate multilocular cystic renal cell carcinoma

目的探讨符合WHO2004年诊断标准的多房囊性肾细胞癌（MCRCC）患者的CT特征及与其他亚型囊性。肾细胞癌（CRCC）的鉴别要点。方法依据是否符合WHO2004年病理诊断标准将40例患者分为两组：MCRCC组及其他亚型CRCC组（CRCC组），复阅CT片，对比肿瘤直径、边界、密度、囊壁及分隔最大厚度、钙化、强化值等CT征象。采用ROC曲线法确定相关指标的临界值及诊断的特异度、灵敏度。结果MCRCC组17例，CRCC组23例。MCRCC多表现为囊壁薄、分隔细小、无明显结节的囊性占位。囊壁及分隔最大厚度是鉴别MCRCC及其他亚型CRCC的惟一CT征象（P〈0．01），其临界值为6mm，诊断的灵敏度和特异度分别为89％和75％。结论囊壁及分隔厚度小于6mm是鉴别MCRCC与其他亚型CRCC的主要CT征象。

Objective To determine the main CT features and the key points of differential diagnosis of multilocular cystic renal cell carcinoma （MCRCC） classified according to 2004 WHO pathological diagnostic criteria. Methods According to the criteria, 40 patients were divided into two groups： MCRCC group and other subtypes of cystic renal cell carcinoma （CRCC）. The CT findings were evaluated and compared between two groups for cystic content, wall, septum, nodularity, calcification and enhancement. ROC curve was used to determine the cut-off value of the possible CT feature which could distinguish MCRCC from other subtypes of CRCC. Results Seventeen cases of MCRCC group and 23 eases of CRCC group were included in this study according to the diagnostic criteria. MCRCC appeared as a welldefined multilocular cystic mass with thin wall and sepia and no expansile solid nodules. Thickness of cysticwall and/or septum is was main CT findings to distinguish MCRCC from other subtypes of CRCC （P 〈 0.01 ）. The cut-off value of the thickness was 6 mm and its sensibility, specificity was 89% ,75% respectively. Conclusion Cystic wall and/or septum with a thickness of less than 6 mm are the main CT findings to distinguish MCRCC from other subtypes of CRCC.