Granulocytic sarcoma of the prostate. Two cases causing urinary obstruction.

Two cases of patients with prostatic granulocytic sarcoma in whom urinary obstruction occurred are presented. The diagnosis was made by tissue examination with hematoxylin and eosin and specific esterase stains. One patient had a myelodysplastic syndrome and the other patient had acute myeloblastic leukemia. In both cases the diagnosis of prostatic granulocytic sarcoma was unexpected. Granulocytic sarcomas should be considered in the differential diagnosis of urinary obstruction in patients with myeloproliferative or myelodysplastic syndromes.