Cao Jinfeng, Dong Jinye, Su Ge, Zhang Baohua, Zhu Lingchen, Wang Min, Li Qilin, Zhang Lesong, Wang Dejian, Luo Xin
Department of Radiology, Zibo Central Hospital, Zibo, China.
Department of Ultrasound, Weifang People's Hospital, Weifang, China.
Transl Androl Urol. 2024 May 31;13(5):792-801. doi: 10.21037/tau-24-141. Epub 2024 May 28.
An accurate and noninvasive method to determine the preoperative clear-cell renal cell carcinoma (ccRCC) pathological grade is of great significance for surgical program selection and prognosis assessment. Previous studies have shown that diffusion-weighted imaging (DWI) has moderate value in grading ccRCC. But DWI cannot reflect the diffusion of tissue accurately because it is calculated using a monoexponential model. Intravoxel incoherent motion (IVIM) is the biexponential model of DWI. Only a few studies have examined the value of IVIM in grading ccRCC yet with inconsistent results. This study aimed to compare the value of DWI and IVIM in grading ccRCC.
In this study, 96 patients with pathologically confirmed ccRCC were evaluated by DWI and IVIM on a 3-T scanner. According to the World Health Organization/International Society of Urological Pathology (WHO/ISUP) classification system, these patients were divided into two groups: low-grade (grade I and II) and high-grade (grade III and IV) ccRCC. The apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction of pseudodiffusion () values were calculated. The Mann-Whitney test, receiver-operating characteristic (ROC) analysis, and the Delong test were used for statistical evaluations.
(I) According to the WHO/ISUP nuclear grading system, 96 patients were divided into low-grade (grade I and II, 45 patients) and high-grade (grade III and IV, 51 patients) groups. (II) Compared with patients of low-grade ccRCC, the ADC and D values of those with high-grade ccRCC decreased while the D* and values increased (P<0.05). (III) The cutoff value of the ADC, D, D*, and in distinguishing low-grade from high-grade ccRCC was 1.50×10 mm/s, 1.12×10 mm/s, and 33.19×10 mm/s, 0.31, respectively; the area under the curve (AUC) for the ADC, D, D*, and values was 0.871, 0.942, 0.621, and 0.894, respectively, with the AUC of the D value being the highest; the sensitivity for the ADC, D, D*, and values was 94.12%, 92.16%, 47.06%, and 92.16%, respectively; and the specificity for the ADC, D, D*, and values was 66.67%, 91.11%, 77.78%, and 73.33%, respectively. (IV) Based on the Delong test, AUC was significantly higher than AUC (P=0.02) and AUC (P<0.001), but there was no significant difference between AUC and AUC (P=0.18).
Compared with the monoexponential model DWI, the biexponential model IVIM was more accurate in grading ccRCC.
一种准确且无创的方法来确定术前透明细胞肾细胞癌（ccRCC）的病理分级，对于手术方案的选择和预后评估具有重要意义。既往研究表明，扩散加权成像（DWI）在ccRCC分级中具有中等价值。但由于DWI是使用单指数模型计算的，所以无法准确反映组织的扩散情况。体素内不相干运动（IVIM）是DWI的双指数模型。仅有少数研究探讨了IVIM在ccRCC分级中的价值，且结果不一致。本研究旨在比较DWI和IVIM在ccRCC分级中的价值。
本研究中，96例经病理证实的ccRCC患者在3-T扫描仪上接受了DWI和IVIM检查。根据世界卫生组织/国际泌尿病理学会（WHO/ISUP）分类系统，将这些患者分为两组：低级别（I级和II级）和高级别（III级和IV级）ccRCC。计算表观扩散系数（ADC）、真实扩散系数（D）、伪扩散系数（D*）和伪扩散灌注分数（）值。采用Mann-Whitney检验、受试者工作特征（ROC）分析和Delong检验进行统计学评估。
（I）根据WHO/ISUP核分级系统，96例患者分为低级别（I级和II级，45例患者）和高级别（III级和IV级，51例患者）组。（II）与低级别ccRCC患者相比，高级别ccRCC患者的ADC和D值降低，而D和值升高（P<0.05）。（III）ADC、D、D和在区分低级别与高级别ccRCC时的截断值分别为1.50×10⁻³mm²/s、1.12×10⁻³mm²/s、33.19×10⁻³mm²/s和0.31；ADC、D、D和值的曲线下面积（AUC）分别为0.871、0.942、0.621和0.894，其中D值的AUC最高；ADC、D、D和值的敏感性分别为94.12%、92.16%、47.06%和92.16%；ADC、D、D*和值的特异性分别为66.67%、91.11%、77.
