Up to 60% of primary prostate cancer can be defined by a gene fusion between the androgen-dependent transcription factor transmembrane serine protease 2 (i.e., TMPRSS2) and an ETS family oncogene, most frequently ETS-related gene (ERG) (12, 13), which can be identified by the surrogate detection of ERG protein overexpression by immunohistochemistry (IHC) (14). This evidence concerns the gene ERG and Familial prostate cancer.