[Isolated vesical localization of malignant B-cell lymphoma of low malignancy]

Primary malignant lymphoma of the bladder is infrequent and usually has a low malignancy, with a possibility of long-lasting remission. Our case is that of a 73-year-old woman who presented with a tumor of the bladder revealed by hematuria. She was treated with incomplete endoscopic resection, which showed that the lesion was a B cell lymphoma. After a complementary 60-Gy radiation therapy, remission was complete at 6 months. The histological and immunological study showed the lymphomatous proliferation infiltrating the chorion and the expression of the usual B-lymphocytic markers by the tumoral cells. Lymphoma of the bladder was described for the first time in 1885, and only a few small series of vesical lymphomas have been published since then. The prognosis is usually favorable owing to long-lasting remission. Complete surgical resection does not improve the results, and radiation therapy is the treatment of choice.