Multilobated B-cell lymphoma. Report of a case with immunocytologic diagnosis in pleural fluid.

The cytologic, histologic and immunocytochemical findings in an aggressive case of multilobated lymphoma in an 89-year-old man are described. This unusual variant of non-Hodgkin's lymphoma is morphologically distinct but may be of either T-cell or B-cell origin. A battery of immunocytologic stains on pleural fluid specimens allowed determination of a B-cell (follicular center cell) origin to be made. Previous literature on this neoplasm is briefly reviewed, and the unreliability of morphologic findings in predicting a T-cell or B-cell origin is discussed.