Leiomyoma of the prostate--a rare mesenchymal tumor: a case report.

Prostatic enlargement due to benign adenomatous hyperplasia is very common in elderly males. However, benign mesenchymal tumors, especially true leiomyoma, are rare in prostate. True prostatic leiomyoma has been defined by Kaufman and Berneike as a smooth muscle tumor within the prostate or juxta-prostatic in position, devoid of glandular elements. The recognition of leiomyoma is important because of the potential of malignancy in such cases, and histopathology is the only tool to do so. We describe the case of a 65-year-old male presenting with urinary obstruction for eight months. Per rectal examination revealed an enlarged firm prostate, a trucut biopsy from which showed only stromal tissue. A suprapubic prostatectomy was performed, and histopathological examination revealed a benign smooth muscle tumor (confirmed by immunohistochemistry), in absence of glandular hyperplasia. Thus, a diagnosis of true leiomyoma of the prostate was made. True leiomyoma is a rare tumor in prostate, which can be diagnosed only on histopathological examination. In addition, careful intra-operative and extensive pathologic assessment is mandatory for predicting the potential behaviour.