[Risk factors of renal sinus invasion in clinical T1 renal cell carcinoma patients undergoing nephrectomy]

To summarize the clinicoradiological characteristics of clinical T1 renal cell carcinoma patients and to investigate the risk factors of renal sinus invasion in cT1 renal cell carcinoma patients undergoing nephrectomy.

A retrospective study was conducted in cT1 renal cell carcinoma patients from January 2016 to August 2019 in Department of Urology, Peking University Third Hospital, who underwent partial or radical nephrectomy by analyzing clinicopathological and radiological data. The influencing factors of renal sinus invasion for cT1 renal cell carcinoma were determined by χ² test, Mann-Whitney U test and Logistic regression analysis.

A total of 507 patients were enrolled, including 354 males (69.8%) and 153 females (30.2%). The median age was 59 years and the median body mass index (BMI) was 25.5 kg/m². Eighteen patients (3.6%) had gross hematuria preoperatively. The median tumor diameter was 3.5 cm. Three hundred twenty-two patients (63.5%) were staged clinical T1a and 165 cases (36.5%) were staged clinical T1b. The median R.E.N.A.L. score was 8. Three hundred fifty-nine patients (70.8%) had regular tumor border and 148 (29.2%) irregular. All the patients underwent surgical treatment, including 186 (36.7%) partial nephrectomy and 321 (63.3%) radical nephrectomy. Postoperative pathology showed seventy-five patients (14.8%) had renal sinus invasion, including 18 in cT1a (5.6%) and 57 in cT1b (30.8%). Univariate analysis showed that age (P=0.020), R.E.N.A.L. score (R value, E value, N value, P < 0.001) and tumor border (P < 0.001) were associated risk factors for cT1 renal cell carcinoma with renal sinus invasion. On multivariate binary Logistic analysis, R.E.N.A.L. score (P≤0.020) and irregular tumor border (P=0.001) were independent risk factors.

For cT1 renal cell carcinoma patients undergoing nephrectomy, about 15% had renal sinus invasion postoperatively. High R.E.N.A.L. score and irre-gular tumor border help predicting cT1 renal cell carcinoma renal sinus invasion.