Department of Medical Imaging, The Ottawa Hospital, Ottawa, Canada.
Software Solutions, The Ottawa Hospital, Ottawa, Canada.
Br J Radiol. 2023 Oct;96(1150):20221087. doi: 10.1259/bjr.20221087. Epub 2023 Sep 3.
To determine if CT can differentiate low-grade from high-grade clear cell renal cell carcinoma (ccRCC) in cT1a solid ccRCC.
This retrospective cross-sectional study evaluated 78 < 4 cm solid (>25% enhancing) ccRCC in 78 patients with renal CT within 12 months of surgery between January 2016 and December 2019. Two radiologists (R1/R2), blinded to pathology, independently recorded mass:size, calcification, attenuation and heterogeneity (5-point Likert scale) and recorded a 5-point ccRCC CT Score. Multivariate logistic regression (LR) was performed.
There were 64.1% (50/78) low-grade (5/50 Grade 1 and 45/50 Grade 2) and 35.9% (28/78) high-grade (27/28 Grade 3 and 1/28 Grade 4) tumors.Unenhanced CT attenuation was higher (35.9±10.3 R1 and 34.9±10.7 R2 high-grade 29.7±10.2 R1 and 29.5±9.8 R2 low-grade, =0.01-0.02), absolute corticomedullary phase attenuation ratio (CMphase-ratio; 0.67±0.16 R1 and 0.66±0.16 R2 0.93±0.83 R1 and 0.80±0.33 R2, =0.04-0.05) and 3-tiered stratification of CMphase-ratio (p=0.02) lower in high-grade tumors.A two-variable LR-model including unenhanced CT attenuation and CM.phase-ratio achieved area under the receiver operator characteristic curve of: 73% (95% confidence intervals 59-86%) and 72% (59-84%) for R1 and R2.ccRCC CT score differed by ccRCC grade (<0.01 R1, R2) with high-grade tumors occurring most commonly in moderately enhancing ccRCC score 4 (46.4% [13/28] R1 and 54% [15/28]).
Among cT1a ccRCC, high-grade tumors have higher unenhanced CT attenuation and are less avidly enhancing.
High-grade ccRCC have higher attenuation (possibly due to less microscopic fat) and lower corticomedullary phase enhancement compared to low-grade tumors. This may result in categorization of high-grade tumors in lower ccRCC diagnostic algorithm categories.
确定 CT 是否可以区分 T1a 期实性透明细胞肾细胞癌（ccRCC）中的低级别和高级别。
本回顾性横断面研究纳入了 2016 年 1 月至 2019 年 12 月间 78 例在术后 12 个月内行肾 CT 检查的患者中的 78 个<4cm 的实性（>25%增强）ccRCC。两位放射科医生（R1/R2）在不了解病理的情况下独立记录肿块大小、钙化、衰减和异质性（5 分李克特量表），并记录 ccRCC CT 评分（5 分）。采用多变量逻辑回归（LR）分析。
肿瘤中低级别（5/50 级 1 和 45/50 级 2）占 64.1%（50/78），高级别（27/28 级 3 和 1/28 级 4）占 35.9%（28/78）。未增强 CT 衰减较高（R1 高分级为 35.9±10.3，R2 高分级为 34.9±10.7；R1 低分级为 29.7±10.2，R2 低分级为 29.5±9.8，=0.01-0.02），绝对皮质髓质期增强比值（CMphase-ratio；R1 高分级为 0.67±0.16，R2 高分级为 0.66±0.16；R1 低分级为 0.93±0.83，R2 低分级为 0.80±0.33，=0.04-0.05）和 CMphase-ratio 的三分层分层（p=0.02）在高级别肿瘤中较低。包括未增强 CT 衰减和 CMphase-ratio 的两变量 LR 模型在 R1 和 R2 中的受试者工作特征曲线下面积分别为：73%（95%置信区间 59-86%）和 72%（59-84%）。ccRCC CT 评分与 ccRCC 分级有关（<0.01 R1，R2），高级别肿瘤最常见于中度增强 ccRCC 评分 4（R1 为 46.4%[13/28]，R2 为 54%[15/28]）。
在 T1a 期 ccRCC 中，高级别肿瘤的未增强 CT 衰减较高，增强程度较低。
与低级别肿瘤相比，高级别 ccRCC 的衰减较高（可能是由于微观脂肪较少），皮质髓质期增强程度较低。这可能导致在较低的 ccRCC 诊断算法类别中对高级别肿瘤进行分类。
