MP46-15: Survival of Patients with Squamous Differentiated Urothelial Carcinoma Compared to Pure Urothelial Carcinoma Following Radical Cystectomy in a Rural Healthcare System
Introduction: Approximately 80% of urothelial carcinoma (UC) is pure while the other 20% is comprised of variant histology. The most common histological variant is squamous differentiation urothelial carcinoma (SqUC). Small series suggest an overall poor prognosis for SqUC compared to pure UC (pUC). The aim of this study is to compare survival outcomes between patients with SqUC and pUC following radical cystectomy in a large, rural healthcare system. Methods: A total of 335 patients were scheduled for cystectomy at a rural tertiary care center between 2008 to 2019. Patients were followed post-operatively and evaluated for recurrence. Recurrence free survival (RFS) was defined as time after cystectomy without clinical evidence of disease until last follow up or date of death. Patients that underwent planned cystectomy that were unable to be performed due to extent of disease or mixed variant/differentiation histology will be excluded from analysis. Pathology from TURBT and cystectomy will be reviewed for inclusion. Statistical significance will be determined using XLSTAT software with log-rank test using a p-value less than 0.05. Results: Of the 333 patients that underwent planned cystectomy, 225 (67.6%) were pUC, 47 (14.1%) were SqUC, 42 (12.6%) were mixed variant/differentiated UC, and 19 (5.7%) were non-UC malignancies. Furthermore, 32 (9.6%) radical cystectomies were aborted due to extent of disease. Average age at time of cystectomy for SqUC and pUC were 68.4 and 68.7 years, respectively. Overall survival in SqUC was significantly lower with median of 28 months compared to 56 months for pUC (p= 0.011). This is demonstrated as a Kaplan-Meier survival curve in Figure 1. The SqUC group also had significantly lower RFS with median of 15 months compared to 50 months for pUC group(p=0.032)(Figure 2). Conclusions: Urothelial carcinoma with squamous differentiation has significantly lower overall survival and recurrent free survival compared to pUC after radical cystectomy in the rural healthcare setting. SOURCE OF Funding: None
