Clinicopathologic correlation is essential for diagnosis of metastatic aggressive variant prostate carcinoma: A series of two cases

Abstract

A subset of patients with castrate resistant prostate cancer, may evolve into androgen receptor‐independent phenotype, clinically characterized by low serum levels of prostate-specific antigen and rapidly progressive disease course, referred to as aggressive variant prostate carcinoma (AVPCa). Essentially, a clinical diagnosis,the increasing incidence has highlighted the need to identify potential targeted therapy options which needs tissue from primary or metastatic site. We present a series of 2 metastatic carcinomas of prostate origin with clinical features and molecular signature of AVPCa. The biopsies of metastatic sites revealed a carcinoma with squamous and neuroendocrine differentiation in one case and the second case showed an adenocarcinoma with neuroendocrine differentiation. Both tumors were negative for prostate-specific markers and positive for neuroendocrine markers. The morphologic heterogeneity and inconsistent immunohistochemistry of AVPCa at the site of metastasis emphasizes the role of interdisciplinary diagnostic approach to confirm prostate origin in this subset of tumors.