These results suggest that obesity is linked with poorer prostate cancer prognosis primarily in men with tumors harboring the gene fusion TMPRSS2:ERG..     ///     TMPRSS2:ERG is a hormonally regulated gene fusion present in about half of prostate tumors.     ///    "We investigated whether obesity, which deregulates several hormonal pathways, interacts with TMPRSS2:ERG to impact prostate cancer outcomes. "    ///    ERG overexpression (a TMPRSS2:ERG marker) was assessed by immunohistochemistry of tumor tissue from radical prostatectomy or transurethral resection of the prostate.     ///    Modification of the association between obesity and lethal prostate cancer by TMPRSS2:ERG.. 