T8 chronic lymphocytic leukemia. A distinctive disorder related to T8 lymphocytosis.

A case of T chronic lymphocytic leukemia (CLL) was first suspected on histologic and cytochemical examination of a splenectomy specimen. Later the patient became frankly leukemic with an E+/T3+/T8+/T4- phenotype. From our case and other reported cases of T-CLL studied with monoclonal antisera, the authors conclude that there are significant clinical and morphologic differences between T4 CLL and T8 CLL. In contrast to T4 CLL, T8 CLL characteristically presents with relatively low lymphocyte counts, little organ involvement, and often only discreet bone marrow involvement, and has a long clinical course. The leukemic cells are often large and have abundant cytoplasm with azurophilic granules. Similar features in cases reported as T8 lymphocytosis with neutropenia lead us to consider both entities part of a spectrum of the same disorder.