CT 早期暗皮质带征鉴别透明细胞肾细胞癌与乏脂肪血管平滑肌脂肪瘤和探测肿瘤假包膜。

Early dark cortical band sign on CT for differentiating clear cell renal cell carcinoma from fat poor angiomyolipoma and detecting peritumoral pseudocapsule.

机构信息

Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Women's Medical University, 8-1, Kawada-cho, Shinjuku-ku, Tokyo, 162-8666, Japan.

Department of Urology, Tokyo Women's Medical University, 8-1, Kawada-cho, Shinjuku-ku, Tokyo, 162-8666, Japan.

出版信息

Eur Radiol. 2021 Aug;31(8):5990-5997. doi: 10.1007/s00330-021-07717-z. Epub 2021 Feb 9.

DOI:10.1007/s00330-021-07717-z

PMID:33559699

Abstract

OBJECTIVES

To retrospectively evaluate whether the early dark cortical band (EDCB) on CT can be a predictor to differentiate clear cell renal cell carcinoma (ccRCC) from fat poor angiomyolipoma (Fp-AML) and to detect peritumoral pseudocapsules in ccRCC.

METHODS

The EDCBs, which are comprised of unenhanced thin lines at the tumor-renal cortex border in the corticomedullary phase, on the CT images of 342 patients who underwent partial nephrectomy were evaluated. Independent predictors among the clinical and CT findings for differentiating ccRCC from Fp-AML were identified using multivariate analyses. The diagnostic performance of the EDCB for diagnosing peritumoral pseudocapsule in ccRCC and differentiating ccRCC from Fp-AML was calculated.

RESULTS

The EDCB was observed in 157 of 254 (61.8%) ccRCCs, 4 of 31 (12.9%) chromophobe RCCs, 1 of 21 (4.8%) papillary RCCs, 3 of 11 (27.3%) clear cell papillary RCCs, 3 of 8 (37.5%) oncocytomas, and 0 of 17 (0%) Fp-AMLs. There was substantial interobserver agreement for the EDCB (k = 0.719). The EDCB was a significant predictor for differentiating ccRCC from Fp-AML (p < 0.001). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value of the EDCB for differentiating ccRCC from Fp-AML were 61.8%, 100%, 100%, and 14.9%, respectively, and those for detecting pseudocapsule in 236 ccRCCs were 62.3%, 68.8%, 96.5%, and 11.7%, respectively.

CONCLUSION

Although diagnostic accuracy of the EDCB for detecting peritumoral pseudocapsule in RCC is inadequate, it can be a predictor for differentiating ccRCC from Fp-AML with high specificity and PPV.

KEY POINTS

• The early dark cortical band (EDCB) sign is observed in nearly two-thirds of clear cell renal cell carcinoma (ccRCC) that are treated by partial nephrectomy and have substantial interobserver agreement. • The EDCB is a significant predictor for differentiating ccRCCs from fat poor angiomyolipomas, with a high specificity and positive predictive value. • Diagnostic accuracy of the EDCB for detecting peritumoral pseudocapsule in ccRCC is inadequate, though better than those in the nephrographic and excretory-phase images.

摘要

目的

回顾性评价 CT 早期暗皮质带（EDCB）能否作为鉴别透明细胞肾细胞癌（ccRCC）与乏脂肪血管平滑肌脂肪瘤（Fp-AML）的预测指标，并检测 ccRCC 的肿瘤假包膜。

方法

对 342 例行部分肾切除术患者的 CT 图像进行分析，评估肿瘤-肾皮质交界区皮质期呈未增强细线状的 EDCB。采用多因素分析确定鉴别 ccRCC 与 Fp-AML 的临床和 CT 表现中的独立预测因素。计算 EDCB 对诊断 ccRCC 肿瘤假包膜及鉴别 ccRCC 与 Fp-AML 的诊断效能。

结果

254 例 ccRCC 中 157 例（61.8%）、31 例嫌色细胞 RCC 中 4 例（12.9%）、21 例乳头状 RCC 中 1 例（4.8%）、11 例透明细胞乳头状 RCC 中 3 例（27.3%）、8 例嗜酸细胞瘤中 3 例（37.5%）、17 例 Fp-AML 中均未见 EDCB。EDCB 的观察者间一致性较好（k=0.719）。EDCB 是鉴别 ccRCC 与 Fp-AML 的显著预测指标（p<0.001）。EDCB 鉴别 ccRCC 与 Fp-AML 的敏感度、特异度、阳性预测值（PPV）和阴性预测值分别为 61.8%、100%、100%和 14.9%，在 236 例 ccRCC 中检测肿瘤假包膜的敏感度、特异度、PPV 和阴性预测值分别为 62.3%、68.8%、96.5%和 11.7%。