Adult genitourinary sarcoma: A population-based analysis of clinical characteristics and survival

Abstract

Background: Sarcomas of the genitourinary (GU) tract are exceedingly rare, accounting for just 1% to 2% of malignancies treated by urologic surgeons. We perform a thorough investigation of incidence and mortality in the United States using the Surveillance, Epidemiology, and End Results (SEER) database. Patients and Methods: The SEER 18 database was used to identify patients diagnosed with genitourinary sarcoma over the age of 16. Data on demographics and tumor characteristics were collected. Survival analysis was performed on the most common primary tumor sites. Results: The search identified 3,007 patients with GU sarcomas from 1973 to 2015. In order of descending incidence, tumors presented in the bladder, kidney, paratestis, and scrotum. Amongst sarcomas arising in the bladder, leiomyosarcomas exhibited the longest median survival time (overall survival (OS) 62 months), while carcinosarcomas had the shortest (OS 9 months). Metastatic disease decreased leiomyosarcoma OS to 3 months. When comparing renal tumors, liposarcomas had the longest median survival time (OS 45 months) and carcinosarcomas had the shortest (OS 6 months). Older age (P < 0.001 and P = 0.015) and T4 disease (P = 0.005 and P < 0.001) predicted for worse survival amongst bladder and renal sarcomas, respectively. High tumor grade (P < 0.001) and node positive disease (P = 0.024) also affected survival amongst renal tumors. Conclusions: Tumors most commonly present in the bladder, kidney, paratestis, and scrotum, with kidney sarcomas having markedly dismal survival outcomes. Survival of identical histologic types varied by primary tumor location, suggesting that treatment strategies should be refined by type of sarcoma and primary tumor location within the GU tract.