TMPRSS2‐ERG fusion impacts anterior tumor location in men with prostate cancer

Background In prostate cancer (PCa), lack of androgen receptor (AR) regulated TMPRSS2‐ETS‐related gene (ERG) gene fusion (ERGnegative) status has been associated with African American race; however, the implications of ERG status for the location of dominant tumors within the prostate remains understudied. Methods An African American‐enriched multiinstitutional cohort of 726 PCa patients consisting of both African American men (AAM; n = 254) and European American men (EAM; n = 472) was used in the analyses. Methods of categorical analysis were used. Messenger RNA (mRNA) expression differences between anterior and posterior tumor lesions were analyzed using Wilcoxon rank‐sum tests with multiple comparison corrections. Results Anti‐ERG immunohistochemistry staining showed that the association between ERG status and anterior tumors is independent of race and is consistently robust for both AAM (ERGnegative 81.4% vs. ERGpositive 18.6%; p = .005) and EAM (ERGnegative 60.4% vs. ERGpositive 39.6%; p