Chronic reticulolymphocytic leukemia: Reclassification of “leukemic reticuloendotheliosis” through functional characterization of the circulating mononuclear cells

The circulating mononuclear cells that distinguish the disease often called “leukemic reticuloendotheliosis” have been redefined by recently developed cytologic and functional criteria. As a result, we propose that the disease be called “chronic reticulolymphocytic leukemia.” Although by light microscopy the abnormal cells displayed features of both lymphocytes and reticulum cells, further analysis demonstrated their lymphocytic character. Fine structural analysis revealed sparse endoplasmic reticulum and small Golgi apparatus, which are recognized lymphocytic features. Pseudopodic extrusions and ameboid motion were present, suggesting reticulum cells, but the cells performed as lymphocytes in that they synthesized IgG, with type K and L light chains, failed to adhere to Nylon® fibers and did not exhibit phagocytosis.