Outcomes and prognosticators of stage 4 renal cell carcinoma with pathological T4 primary lesion using a large Canadian multi-institutional database

Abstract

Introduction: The primary objective of this study was to evaluate outcomes and prognosticators in patients who underwent radical nephrectomy (RN) or cytoreductive nephrectomy (CN), depending on the clinical stage of disease preoperatively, with a pathological T4 (pT4) renal cell carcinoma (RCC) outcome. There is little data on the outcome of this specific subset of patients. Methods: From 2009‒2016, we identified patients in the Canadian Kidney Cancer information system (CKCis) who underwent RN or CN and were found to have pT4 RCC. Clinical, operative, and pathological variables were analyzed with univariable and multivariable Cox proportional hazard models to identify factors associated with overall survival (OS). Survival curves were created using Kaplan-Meier methods and compared using the log-rank test. Results: A total of 82 patients were included in the study cohort. Median patient age was 62 years (interquartile range [IQR] 55, 70). The majority of patients had clear-cell histology, 50 (61%), and 14 (17%) had sarcomatoid characteristics. Median followup was 12 months (IQR 3, 24). At last followup, eight (10%) patients are alive with no evidence of disease, 27 (33%) are alive with disease, four (5%) were lost to followup, 36 (44%) died of disease, and seven (8%) died of other causes. Tumor histologic subtype (clear-cell vs. non-clear-cell) (p=0.0032), larger tumor size (cm) (p=0.012), and Fuhrman grade (G4 vs. G2‒G3) (p=0.045) were significantly associated with mortality in a multivariable Cox regression model. Conclusions: For patients with pT4 RCC after RN or CN, survival is poor. Sarcomatoid features, non-clear-cell histology, and presence of systemic symptoms were associated with worse OS.