OUTCOME AFTER CYTOREDUCTIVE NEPHRECTOMY FOR METASTATIC RENAL CELL CARCINOMA IS PREDICTED BY FRACTIONAL PERCENTAGE OF TUMOUR VOLUME REMOVED

Abstract

OBJECTIVE To determine if the fractional percentage of tumour volume (FPTV) removed at cytoreductive nephrectomy predicts disease-specific survival (DSS), as metastatic renal cell carcinoma ((M+)RCC) is associated with poor overall survival with only a 10–20% patient survival at 2 years. PATIENTS AND METHODS The Columbia Urologic Oncology Database was reviewed; 1016 patients had renal surgery from 1988 to 2005, 78 patients with (M+)RCC underwent nephrectomy. The FPTV removed was determined using pathological and imaging reports. The patients were stratified as having a > or <90% FPTV. Kaplan–Meier analysis with log-rank test was used to determine survival advantage between groups. A Cox proportional hazard model was used for FPTV in both univariate and multivariate analyses. Secondary analyses were conducted to determine if the size of the primary tumour or volume of metastases affected outcome and if the FPTV affected hospitalization time. RESULTS In all, 55 patients had their FPTV calculated exactly; 45 had a >90% FPTV. The median DSS times were 11.6 and 2.9 months for patients with >90% and 90% FPTV in a univariate model (P = 0.016) and 0.29 in multivariate analysis (P = 0.02). Patients with a <90% FPTV spent a greater percentage of time hospitalized before death, 21.2% vs 6.5% (P = 0.03). CONCLUSION For patients with (M+)RCC, overall survival is limited, but can be extended by cytoreductive nephrectomy. The FPTV expected to be removed is a simple and available method to counsel patients regarding the benefits of surgical intervention.