Transrectal ultrasound and biopsy in diagnosis of malakoplakia of prostate.

We report our experience with the use of transrectal ultrasound and ultrasound-guided needle biopsy in the diagnosis of 4 cases of malakoplakia of the prostate. Prostatic malakoplakia is rare with a total of 25 cases reported in the literature. It may simulate carcinoma on digital rectal examination and transrectal ultrasound. Herein are 4 additional cases in which transrectal ultrasound of the prostate was compatible with carcinoma. Subsequent needle biopsy of the suspicious regions revealed the classic pathologic features of malakoplakia. Malakoplakia is a difficult pathologic diagnosis, and the prevalence of this disease may be underestimated. As the use of transrectal ultrasound becomes more common in diagnosing carcinoma of the prostate, and due to the difficulty in diagnosing malakoplakia pathologically, we recommend maintaining a high index of suspicion for malakoplakia to avoid possible unnecessary radical surgery.