Abstract
The vast majority of cases of T cell large granular lymphocyte (T-LGL) leukemia have a CD3+, CD4-, CD8+ phenotype and express the alphabeta T cell receptor. Whether the rare gammadelta variant should be included in the same diagnostic category is currently unclear. Two well-characterized cases of gammadelta T-LGL leukemia were identified by our laboratory in 2007. These two cases and other reports of gammadelta T-LGL leukemia were compared with the common alphabeta variant. Other than more often being negative for both CD4 and CD8 (in about 35% to 40% of cases), the gammadelta variant of T-LGL leukemia is similar to the common alphabeta type in virtually all respects and should be included in the general category of T-LGL leukemia. However, it is important to exclude other more aggressive gammadelta T cell lymphoproliferative disorders.