TMPRSS2-ERG gene fusion was found in 47% (14/30) of prostatic small cell carcinoma.     ///    Small cell carcinoma of the prostate demonstrates TMPRSS2-ERG rearrangement with comparable frequency to prostatic adenocarcinoma.     ///    ERG-TMPRSS2 rearrangement is shared by concurrent prostatic adenocarcinoma and prostatic small cell carcinoma and absent in small cell carcinoma of the urinary bladder: evidence supporting monoclonal origin.. 