A case of malignant lymphoma of the prostate and the root of penis

Abstract

We report a case of malignant lymphoma of the prostate and the root of penis with appearance of tumor cells in the urine. A 81-year-old man complained of pain on initiating micturition and a mass in the root of penis. Since urinary cytology revealed malignant lymphoma cells, thorough examination was performed, resulting in the diagnosis of malignant lymphoma of the prostate. The prostate biopsy specimen revealed infiltration by atypical lymphocytes consisting of centrocytes with cleaved cells. Immunohistochemically, the tumor cells were positive for UCHL-1 but negative for L 26, indicating malignant lymphoma of T-cell origin. The patient was treated with three couses of CHOP chemother apy, but died 18 months ater of brain metastasis. Malignant lymphoma of the prostate, whether primary or secondary, is uncommon and is rarely detected on urinary cytology. However, urinary cytology appeared to be useful as a screening test for malignant lymphoma of the prostate.