TMPRSS2 and posterior cortical atrophy: The TMPRSS2:ERG (T/E) gene fusion, resulting from a chromosomal rearrangement of ERG (v-ets erythroblastosis virus E26 homolog (avian)) to the androgen responsive gene TMPRSS2 (transmembrane protease, serine 2), is the most frequent somatic alteration in PCa [3], and detectable in 50% of the tumors [4].