Chronic T-cell Leukemia/Lymphoma.

This issue of Cancer Control focuses on the clinicopathologic features of chronic T-cell leukemia/ lymphoma. Chronic leukemia of T-cell origin was first identified by Brouet and colleagues in 1975. Several classification systems for T-cell lymphoid malignancies have been proposed since then. The French-American-British (FAB) Cooperative Group’s proposal for classification designated four subgroups: (1) T-cell CLL or large granular lymphocyte (LGL) leukemia, (2) T-prolymphocytic leukemia, (3) adult T-cell leukemia/lymphoma, and (4) Sezary’s syndrome.2 In 1990, the Morphologic, Immunologic, Cytogenetic (MIC) Cooperative Study Group reviewed this FAB classification and determined that LGL leukemia instead of T-CLL was the preferable terminology. These four subgroups have also been recognized as district entities in the REAL classification.4