Monstrous epithelial cell clusters in the seminal vesicle

A 60-year-old man presented with dysuria and elevated PSA (6.95 ng/ml). Needle biopsies of the prostate revealed well differentiated adenocarcinoma of Gleason's score 6. Prostatectomy and bilateral seminal vesiculotomy were performed. The material was totally cut into 16 preparations. The prostate showed well differentiated adenocarcinoma. The left seminal vesicle showed intraluminal monstrous large epithelial cells with acidophilic cytoplasm and hyperchromatic nuclei, simulating carcinoma cells. Lipochrome pigment was present in the monstrous cells, and some monstrous cells showed large bizarre nuclei. Such monstrous cells were also present in the mucosal seminal vesicle epithelium, and gradual merge between the intraluminal and mucosal monstorous epithelium. Immunohistochemically, the monstrous epithelial cells showed the following reactions: pancytokeratin (AE1/3, CAM5.2) +, cytokeratin (CK) 5/6 +, CK34βE12 -, CK7 +, CK8 -, CK14 -, CK18 +, CK19+, CK20 -, Ki-67 0%, p53 -, P63 -, NSE -, CEA -, EMA -, CA19-9 -, ER -, PgR -, HER2 -, HepPar1 -, CD34 -, CD10 +, PSA -, AMACR -, Desmin -, ASMA -, CD68 -, S100 -, CD45 -, synaptopysin -, TTF-1 -, CDX-2 -, MUC1 -, MUC2 -, MUC5AC - MUC6 +, CD56 -, PAS -, dPAS -, and alcian blue +. The immunoprofile of normal seminal vesicle epithelium was as follows: pancytokeratin (AE1/3, CAM5.2) +++, cy-tokeratin (CK) 5/6 +++, CK34βE12 -, CK7 +++, CK8 +, CK14 -, CK18 +++, CK19, +++, CK20 -, KI-67 1%, p53 -, P63 +++, NSE -, CEA - EMA -, CA19-9 -, ER -, PgR -, HER2 +, HepPar1 -, CD34 -, CD10 +, PSA -, AMACR -, Desmin -, ASMA -, CD68 -, S100 - , CD45 -, synaptopysin -, TTF-1 -, CDX-2 -, MUC1 -, MUC2 -, MUC5AC -, MUC6 +++, CD56 -, PAS -, dPAS -, and alcian blue +. That is, the immunophenotype was very similar but much weaker in monstrous cells than in normal seminal vesicle epithelium. These findings suggest that the monstrous seminal vesicle epithelial cells are degenerative changes. The monstrous epithelial cells should not be mistaken for carcinoma.