The natural history, treatment pattern, and survival of the patients with micropapillary bladder.

Abstract

e15015 Background: Micropapillary bladder carcinoma (MPBC) is a rare variant of urothelial carcinoma. The objective of this study was to examine the epidemiology, natural history, and prognostic factors of MPBC using population-based registry. Methods: The Surveillance, Epidemiology, and End Results (SEER) Program database was used to identify cases of MPBC by tumor site and histology codes. The clinical, demographic characteristics, treatment and survival of MPBC were examined. Results: A total of 98 cases of histology confirmed MPBC were identified between 2001 and 2007, this accounted for approximately 0.01% of all primary bladder tumors during the study period. Median age of the patients was 72 years (range 26-95). Of all the patients with MPBC, 56.1% had muscle invasive disease; 75.5% of patients had poorly or undifferentiated histology. A total of 30.6% of all patients (2.3% superficial disease; 52.7% of muscle-invasive MPBC) had radical or partial cystectomy. By logistic regression analysis, nonmuscle-invasive MPBC (OR 62.5, 95% CI 7.2-542.3) was associated with lower rate of utilization of cystectomy. The 1-, 3- and 5-year overall survival rate of MPBC were 84.5%, 57.3% and 42.3%. In multivariate analysis, tumor stage (HR 4.7, 95% CI 1.0-21.8) was found to be the only significant predictor for cancer-specific survival. Conclusions: The optimal therapy for MPBC remains undermined. Emphasis on early detection is needed to improve the outcome for patients with this malignancy.