Malakoplakia associated with prostatic adenocarcinoma: Report of 4 cases and literature review.

Malakoplakia is an inflammatory process that has been rarely reported in the prostate. Malakoplakia in association with prostatic carcinoma is exceedingly rare with only 4 previously reported cases. We describe the clinical features and the associated pathology in 4 patients who demonstrated malakoplakia of the prostate in association with prostatic adenocarcinoma. Prostatic malakoplakia presenting in association with prostatic adenocarcinoma was identified in 4 patients through a search from the records of 3 institutional databases with large in-house and consult uropathology practices. In 2 of the patients the diagnostic needle biopsy contained only prostatic carcinoma; malakoplakia in association with prostatic carcinoma was documented on prostatectomy, performed 15 and 8weeks after the biopsy, respectively. Both patients experienced urinary infections during the interval between the biopsy and the prostatectomy. The third and fourth patient had a long-standing history of "prostatitis", and acute urinary tract infection with urinary retention, respectively. The needle biopsy in both patients showed concomitant malakoplakia and prostatic carcinoma. One of them also had malakoplakia on the initial biopsy containing only atypical glands and on the subsequent one demonstrating carcinoma. One patient was treated conservatively and one with prostatectomy. Although coexistent prostatic carcinoma and malakoplakia are exceedingly rare, malakoplakia can likely occur as an exceptionally rare complication of a prostate needle biopsy, particularly in individuals with long-term or acute urinary tract infections at the time of the biopsy.