Perioperative morbidity, oncological outcomes and predictors of pT3a upstaging for patients undergoing partial nephrectomy for cT1 tumors.

Abstract

To evaluate perioperative morbidity, oncological outcome and predictors of pT3a upstaging after partial nephrectomy (PN). Retrospective study of 1042 patients who underwent PN for cT1N0M0 renal cell carcinoma between 2007 and 2015. A total of 113 cT1 patients were upstaged to pT3a, while 929 were staged as pT1. Demographic, perioperative and pathological variables were reviewed. We compared the clinico-pathological characteristics, perioperative morbidity and oncological outcomes between pT3a and pT1 groups. Multivariate regression evaluates variables associated with T3a upstaging. Recurrence-free survival (RFS) and overall survival analyses were performed. Survival curves were compared using log-rank test. The pT3a tumors were high complexity tumors (median RENAL score 8 vs. 7, p < 0.01), higher hilar (h) location (27.5 vs. 14.8%, p < 0.01), higher grade (57.5 vs. 38.2%, p < 0.01), and higher positive surgical margins (18.6 vs. 5.8%, p < 0.01. Patients with pT3a had a higher estimated blood loss, transfusion rate, ischemia time and overall complications, though there were no differences in median e-GFR decline and major (Grade III-V) complications. Five-year RFS was 78.5% for pT3a group vs. 94.6% for pT1 group (log-rank p < 0.01). Male gender (OR 2.2, p < 0.01), and R.E.N.A.L. score (OR 2.3, p = 0.01) were preoperative predictors of upstaging. We acknowledge limitations in our study, most are inherent problems of retrospective studies. Perioperative morbidity, after partial nephrectomy, is acceptable in cT1/pT3 tumors in comparison to cT1/pT1; however, upstaged patients had a worse oncological outcome. cT1/pT3a tumors are associated with adverse clinico-pathological features. Preoperative risk predictors of upstaging were higher R.E.N.A.L. score and male gender.