Primary non-Hodgkin's lymphoma of the urinary bladder.

Primary non-Hodgkin's lymphoma of the bladder is a rare entity and when found in such an unusual location is often difficult to distinguish from other vesical or extravesical neoplasms. Understanding of the pathobiological characteristics of this malignancy has been hampered not only because of its rarity but also by the previous confusion in its nomenclature. Factors that influence survival most strongly are the stage and the bulk of disease at presentation and the histologic classification of the tumor. We report a case of primary non-Hodgkin's lymphoma of the bladder presenting as a large pelvic mass which dramatically regressed with systemic chemotherapy with simultaneous restoration of the upper dilated urinary tracts. In addition, the incidence, clinical picture, staging procedures, histologic classification and treatment modalities of this disease are reviewed.