Small cell-like change in prostatic adenocarcinoma and intraductallesions – neuroendocrine or not?

Abstract

Background Small cell-like change in prostatic neoplasia (both invasive adenocarcinoma and intraepithelial lesions) is described in three previous reports. None of them to date proved to be associated with overt prostate neuroendocrine carcinoma. Case presentation We report findings from a radical prostatectomy of 80-year-old patient (adenocarcinoma GG5 pT3b with 10% involvement of the gland) with small cell-like change in intraductal carcinoma and in the invasive component. An additional 3.5-mm focus of poorly differentiated carcinoma was observed (PSA, TTF1, chromogranin and CD56 negative; synaptophysin positive in scattered cells; and a Ki67 label index of 50%). Conclusion Our case expands the data accumulated on small cell-like change in prostate neoplasia. As most of other reported cases, there was no expression of neuroendocrine markers or high proliferative index in small-cell like areas. On the other hand, for the first time, a transition morphology between acinar adenocarcinoma and neuroendocrine carcinoma was observed in a prostate with small cell-like change.