Immunocytochemical diagnosis of lymphoma from urine sediment.

: Cytologic studies were done on the urine sediment of a patient with an indolent lymphoma of 20 years' duration. The patient had localized disease in his groins and developed marked swelling in his penis and scrotum and pedal edema shortly after radiotherapy was instituted to the inguinal areas. The urine specimen obtained after chemotherapy showed many large mononucleated malignant cells. These cells were extremely fragile and were best demonstrated by supravital staining of wet preparations. Although morphologic examination could not confidently indicate the origin of these malignant cells, cytochemical and immunocytochemical studies showed them to be monoclonal B lymphocytes. This study suggests that, even under unusually difficult circumstances, a combined cytologic, cytochemical and immunocytochemical approach can be successfully applied for cytodiagnosis.