Here are couple of articles I found:
"Role of Radiotherapy in Ductal (Endometrioid) Carcinoma of the Prostate",
www.ncbi.nlm.nih.gov/pmc/articles/PMC1950740/"Metastatic ductal carcinoma of the prostate: a rare variant responding to a common treatment",
www.ncbi.nlm.nih.gov/pmc/articles/PMC2845672/Hope that helps.
Nellie