[Primary malignant lymphoma of the urinary bladder].

We report 2 cases of primary malignant lymphoma arising in the urinary bladder. The first case was a 64-year-old woman complaining of gross hematuia during the follow-up period of transitional cell carcinoma (grade 2, stage pTa) of the bladder that was treated with TUR in 1989. Her bladder tumor of this time was broad based, not papillary, and situated on the right side wall with bleeding. The pathological diagnosis of transurethral biopsy specimens was non-Hodgkin lymphoma, diffuse large, B cell type. Four courses of CAP chemotherapy was so effective that she has been free of the disease up to now. The second was a 51-year-old woman presenting with painless gross hematuia. A solid, round and intramural tumor, which was recognized on the left side wall by cystoscopy, was resected endoscopically as much as possible. Three courses of VEPA chemotherapy was done because pathologically it was non-Hodgkin lymphoma, diffuse medium, B cell type, although no evidence of other tumors in any organs was fortunately detected with further examinations. She has been doing well without recurrence for 9 months after discharge from the hospital. Primary malignant lymphoma of the bladder is unusual. About 70 cases have been reported in foreign countries, but only 23 cases in Japan. When malignant lymphoma is confined to the bladder, radiation and chemotherapy can be curative, and yet preserve the function of the bladder.