Ductal Adenocarcinoma of the Prostate: Evolution and Current State.

Prostatic ductal adenocarcinoma (PDA) is a rare histological subtype of prostate carcinoma, first described by Melicow and Pachter in 1967 as "endometrial carcinoma of the uterus masculinus." The case for defining PDA as a separate entity rests on its distinctive morphology, aggressive clinical course, and, at times, unusual metastatic patterns. Yet, the frequent coexistence of PDA with acinar adenocarcinoma, together with molecular evidence pointing to a shared clonal origin-such as overlapping ERG rearrangements and other genomic alterations-suggests that PDA may instead represent a histologic variant of acinar prostate cancer. In this review, we explore what is currently known about PDA, tracing its epidemiology, clinical presentation, histopathology, molecular underpinnings, prognosis, and therapeutic challenges.