320排CT双期增强在肾细胞癌常见亚型的鉴别诊断价值

Diagnostic value of dual-phase contrast enhancement in the differential diagnosis of common renal cell carcinoma subtypes by 320-slice CT

目的:探讨320排CT双期增强扫描对肾细胞癌常见亚型的鉴别诊断价值。方法:回顾性分析224例经病理证实肾细胞癌患者的临床资料,其中肾透明细胞癌196例、乳头状肾细胞癌14例、嫌色细胞癌14例。分析肿瘤的形态、钙化、强化方式,使用t检验比较不同病理亚型肾细胞癌强化程度、病灶与腹主动脉的CT比值,并绘制ROC曲线计算曲线下面积、敏感度和特异度。结果:透明细胞癌常表现为不均匀强化,乳头状癌多表现为均匀强化病灶,嫌色细胞癌为均匀强化及实性为主不均匀强化,因此当病灶表现为囊性为主或囊实性混合的不均匀强化时,提示透明细胞癌可能性大(χ2=4.286,P<0.05)。透明细胞癌在皮髓质期、实质期强化程度均明显高于乳头状癌、嫌色细胞癌(P<0.01)。单期相分析时,区分透明细胞癌与乳头状癌的敏感度与特异度为87.76%～92.35%、78.57%～85.71%,透明细胞癌与嫌色细胞癌单期增强诊断的敏感度、特异度为74.49%～87.73%,85.71%～92.86%,且当联合双期增强时,区分透明细胞癌与乳头状癌及嫌色细胞癌,其敏感度、特异度为88.27%～91.33%,85.71～92.82%。结论:在减少电离辐射的同时,320排CT双期增强扫描有助于鉴别肾透明细胞癌与其他肾细胞癌。

Objective： To detect the value of dual-phase contrast enhancement by 320-slice CT in the differential diagnosis of common renal cell carcinoma（RCC） subtypes. Methods： The clinical data of 224 cases of RCC confirmed by pathology were retrospectively analyzed, including 196 cases of clear cell RCC, 14 cases of papillary RCC and 14 cases of chromophobe RCC. The morphology, calcification and strengthening methods of the tumor were analyzed. T test was used to compare the enhancement degree of RCC in different pathological subtypes, the CT ratio between the lesion and the abdominal aorta, and the area under the ROC curve, sensitivity and specificity were calculated. Results： Clear cell RCC commonly manifested heterogeneous, and papillary RCC were homogeneous enhancement, while chromophobe RCC were homogeneous enhancement and solid-based heterogeneous enhancement. Therefore, the possibility of clear cell RCC was suggested when the focus was cystic or cystic and solid mixture inhomogeneous enhancement（χ2=4.286, P0.05）. The enhancement degree of clear cell RCC in cortical and parenchymal phase was significantly higher than that of chromophobe RCC and papillary RCC（P0.01）. The sensitivity and specificity of single-phase contrast enhancement for discriminating clear cell RCC from papillary RCC were 87.76% ～92.35%, 78.57% ～85.71%, the sensitivity and specificity for discriminating clear cell RCC from chromophobe RCC were74.49%～87.73%, 85.71%～92.86%, the sensitivity and specificity of dual-phase contrast enhancement in the differential diagnosis of clear cell RCC, papillary RCC and chromophobe RCC were 88.27% ～91.33%, 85.71%～92.82%. Conclusion： While reducing ionizing radiation, dual-phase contrast enhancement by 320-slice CT is useful in differentiating clear cell RCC from other RCC subtypes.