The Preoperative Predictive Factors for Pathological T3a Upstaging of Clinical T1 Renal Cell Carcinoma

We aimed to determine the oncological outcomes of patients with clinical T1 renal cell carcinoma (RCC) upstaged to pathological T3a and to identify the preoperative predictive factors for upstaging. We retrospectively reviewed 272 patients with clinical T1 RCC who underwent surgical treatment. Thirty-three patients (12%) were upstaged to pathological T3a. These patients had a significantly larger tumor size on computed tomography (p < 0.0001), a higher aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ratio (p = 0.037), and an elevated c-reactive protein (CRP) level (p = 0.014) preoperatively compared with those with pathological T1 RCC. On multivariate analysis, tumor diameter was the only significant preoperative predictive factor for upstaging [hazard ratio (HR), 3.61; 95% confidence interval (CI), 1.32-9.84; p = 0.01]. The AST/ALT ratio tended to be a preoperative predictive factor for upstaging, although it was not significant (HR, 2.14; 95% CI, 0.97-4.73; p = 0.06). Pathological T3a upstaging occurred in 25% of those with a tumor diameter ≥30 mm and a preoperative AST/ALT ratio ≥1.1. There was a significant correlation between pathological T3a upstaging and the number of preoperative risk factors (p = 0.0002). The preoperative tumor diameter and serum AST/ALT ratio can be predictive factors for pathological T3a upstaging in patients with clinical T1 RCC.