Seminal vesicle epithelium in fine-needle aspiration biopsies of the prostate as a pitfall in the cytologic diagnosis of carcinoma.

The morphologic features of seminal vesicle epithelial cells were studied in a material of ca 3,300 fine-needle aspiration biopsies of the prostate. Seminal vesicle material was considered to be found in 50 cases. The most usual and distinctive features in seminal vesicle epithelial cells were yellowish-brown cytoplasmic pigment granules and large hyperchromatic polyploid nuclei. Intranuclear cytoplasmic inclusions, nuclear folding and prominent nucleoli were observed in approximately one third of the cases. Seminal vesicle secretion and stromal cells were seen in most cases, spermatozoa less frequently. The recognition of seminal vesicle epithelial cells in fine-needle aspiration biopsies of the prostate is considered to be important in the avoidance of cytodiagnostic errors.