OBJECTIVES: Carcinoma with basaloidfeatures, known as basaloid carcinoma of prostate, isan extremely rare tumor. We report the clinical, histological and immunohistochemical findings in a case ofprostatic basaloid carcinoma. METHODS/RESULTS: A 68-year old man consultedwith a two-year history of increasing urinary outflowobstruction that developed into acute urinary retention.A routine suprapubic prostatectomy was carried out,following which normal voiding was achieved.Microscopically, the neoplasm showed differenthistological aspects; some areas were typical of basalcell hyperplasia, intermixed with other in which therewas evidence of basaloid carcinoma.Immunohistochemical staining of the basaloid carcinomarevealed cytokeratin 34βE12 immunoreactivity withoutexpression of prostatic specific antigen and prostaticacid phosphatase. CONCLUSION: This case is a very unusual basaloidcarcinoma and may indicate that there is a spectrum inprostate basal cell proliferation.