Outcomes and predictors of survival in testicular sarcomas.

Abstract

404 Background: Testicular sarcomas represent less than 1% of all testicular tumors in adults. Because of their rarity, little is known about the features and outcomes of these tumors. We present an analysis of the prognosis and survival predictors in patients with testicular sarcomas from the Surveillance, Epidemiology, and End Results Program (SEER). Methods: Using the SEER registry, we identified adults with testicular sarcomas between 1980 and 2013. Cases were identified using a combination of ICD-O-3 site and histology codes. The JMP and SEER*STAT 8.3.2 were used for statistical analysis. Overall survival (OS) was analyzed using the Kaplan-Meier method. The prognostic effect of variables was studied using Cox proportional hazards models. Results: We identified 264 patients with testicular sarcomas with a median follow-up time of 9.2 years. The median age at diagnosis was 55 years (range 15-94) and the median tumor size was 6.6 cm (range 0.7-45). 20% of patients with documented staging presented with de novo metastatic disease. Rhabdomyosarcomas were the most common histology (37%). The median OS was 129 months (95%; CI 85-180). OS rates at 1 year and 5 years were 85% and 62% respectively. 53% of deaths were related to cancer. 1-year OS rates for localized, locally advanced and metastatic disease were 91%, 93% and 53% (P<0.0001). Variables that were significant for survival in univariate analysis included age, histology, stage, and surgical resection. Factors that negatively affected survival in multivariate analysis were age >55 years (HR 2; 95% CI, 1.1-3.7), advanced stage (HR 4.8; 95% CI, 2.7-8.4) and surgical unresectability (HR 3.7; 95% CI, 1.1-9.3). Patients with rhabdomyosarcoma had favorable outcomes compared to other histologies (59% vs 17% alive at 10 years, P=0.01). Conclusions: Testicular sarcomas are rare entities with overall good prognosis after surgical resection. Patients presenting with distant metastases, however, have worse outcomes with only about 50% of the patients alive at 1 year. Rhabdomyosarcomas are the most common histology encountered and have relatively better survival. Younger age, earlier stage and surgical resection are factors associated with significantly better outcomes.