Risk Factors for Upstaging, Recurrence, and Mortality in Clinical T1-2 Renal Cell Carcinoma Patients Upstaged to pT3a Disease: An International Analysis Utilizing the 8th Edition of the Tumor-Node-Metastasis Staging Criteria

Abstract

Objective: To investigate risk factors for and outcomes in pathological T3a-upstaging in Renal Cell Carcinoma (RCC), as Tumor-Node-Metastasis staging for T3a RCC was recently revised.

Methods: Multicenter retrospective analysis of patients with clinical T1-T2 RCC, stratified by occurrence of pathologic T3a-upstaging. Primary outcome was recurrence-free survival (RFS). Multivariable analyses (MVA) were conducted for upstaging and recurrence. Kaplan-Meier analysis (KMA) was utilized for RFS and overall survival (OS).

Results: We analyzed 2573 patients (1223 RN/1350 PN). Upstaging occurred in 360 (14.0%). On MVA, higher clinical stage was associated with increasing risk of upstaging [cT1a (referent), odds ratio for cT1b, cT2a, and cT2b was 2.6, 6.5, and 14.1, P < .001]. Higher clinical stage at presentation correlated with increasing risk of recurrence in pT3a-upstaged RCC (cT1a upstaged-pT3a [referent], hazard ratio [HR] for cT1b, cT2a, and cT2b upstaged pT3a was 1.16 [P = .729], 3.02 [P = .013], and 4.5 [P = .003]). Perirenal fat (HR 1.6, P = .038) and renal vein (HR 2.2, P = .006) invasion were associated with increased risk of recurrence; type of surgery was not (P = .157). KMA for RFS and OS in pT3a-upstaged patients demonstrated differences based on initial clinical stage (5-year PFS for cT1a/b, and cT2 upstaged was 84.5%/72.8%, and 44.7%, P < .001; 5-year OS for cT1 and cT2 upstaged was 83.8% and 63.2%, P < .001).

Conclusion: Risk of pT3a-upstaging and recurrence in pT3a-upstaged RCC correlates with clinical stage at presentation. Renal vein and perinephric fat invasion were associated with increased risk of recurrence. PN did not increase risk of recurrence and potential of pT3a-upstaging should not deter consideration of PN.