Development of intermediate and high-risk prostate cancer after testicular cancer.

Abstract

177 Background: Men with a history of testicular cancer are known to have an increased risk of developing prostate cancer (PCa) in epidemiologic studies. We hypothesized they may also have an increased risk of developing intermediate to high-risk PCa. Herein, we present a case-control study to assess the association of a history of testicular cancer and intermediate to high-risk PCa. Methods: We used the eighteen Surveillance, Epidemiology and End Results (SEER) registries to compare men with a history of testicular cancer to a control population of men with a history of melanoma. Melanoma was used as a control group because, to our knowledge, there is no association of melanoma and PCa. Men were excluded if they were not 60 years of age or older to allow for sufficient PCa diagnosis. PCa incidence was only counted if it occurred at least 5 years after the diagnosis of their primary cancer to allow for possible temporal effect of the primary malignancy. Incidence of total and intermediate to high-risk PCa(Gleason score ≥ 7) was compared using Kaplan-Meier (KM) curves. Cox proportional hazards models were utilized to assess for associations of PCa (JMP 10, SAS Inc). Results: 119,781 men with melanoma and 10,365 men with testicular cancer were identified. The incidence of all PCa by age 80 was 2.7% in the control melanoma cohort and 12.3% in the case cohort of men with history of testicular cancer (p<0.0001 for KM survival curves). For intermediate/high-risk disease, the incidence was 1.1% versus 5.7% for each cohort respectively (p<0.0001 for KM survival curves). Testis cancer (versus the control melanoma cohort) was associated with an increased risk of all PCa (HR 4.7, p<0.0001) and intermediate/high-risk PCa (HR 5.5, p<0.0001). These associations persisted even when controlling for race. Conclusions: A history of testicular cancer is associated with a significantly increased risk of developing both PCa and intermediate/high risk PCa.