We report the case of a 51-year-old gentleman presenting with obstructive and irritative urinary symptoms, found to have a large prostate mass on imaging. A radical prostatectomy was performed and pathological diagnosis revealed a 12 cm mammary-type myofibroblastoma replacing the entire prostate. Mammary-type myofibroblastoma is a rare lesion outside of the breast, and is considered benign. This is the first reported case of a mammary-type myofibroblastoma occurring in the prostate.
