Utilization and outcomes of adjuvant radiation therapy after cystectomy for urothelial carcinoma.

Abstract

487 Background: Positive surgical margins with radical cystectomy for invasive urothelial cancer are associated with adverse prognosis. In non-metastatic patients, adjuvant radiation therapy (ART) is sometimes employed for patients with positive margins or locally advanced stage. However, evidence for benefit of ART in these patients to improve survival is limited. In this study, using a national database we investigate the factors associated with use of ART and its impact of the overall survival. Methods: National Cancer Database was queried for patients who underwent radical cystectomy from 2004-2013 for invasive urothelial cancer. Inclusion criteria were urothelial histology, pT2 stage with positive surgical margins or ³pT3 , and no evidence metastasis. Patients with regional or distant metastasis or patient who underwent adjuvant chemotherapy were excluded. Univariate and multivariate analysis performed to assess the factors associated with the use of ART. Overall survival was compared using log rank test. Results: In total, 18,828 patients met the inclusion criteria, of which 359 (1.91%) underwent ART. Mean duration between radical cystectomy and ART was 4.4 months. On univariable analysis, Black or Hispanic race, Medicare/Medicaid insurance status, treatment at community health center, ileal conduit diversion, advanced pathological stage (pT3/T4) were associated with higher use of ART (all p<0.005). On multivariate analysis community health facility and adequate lymph node dissection (>10 lymph nodes excision) were associated with use of ART (all p<0.05) (see table). The use of ART was not associated with improved overall survival. Conclusions: The utilization of ART after radical cystectomy for urothelial carcinoma is low. The benefit of ART on the overall survival is not clear and would need further investigation. [Table: see text]