CD8 expression in B chronic lymphocytic leukemia: A case of immuno-phenotypic aberrancy.

Immuno-phenotyping forms an integral part of laboratory work up of Chronic lymphocytic leukemia (CLL). Aberrant antigen expressions are a known phenomenon in leukemic blasts, however cross lineage antigen expression is rarely seen in mature B cell leukemia, the reported percentages varying from 1% to 3% in Europe and North America. CASE DETAILS: We report a case of Rai stage 1 CLL showing aberrant expression of CD8 on flow cytometry. The patient had stable disease at a follow up of 9 months with no requirement of initiation of treatment. DISCUSSION: CD8 expression in CLL is rare and approximately 120 cases have been reported from Western population. To the best of our knowledge, this is the first case to be reported from India. The prognostic significance has been variably reported from favorable to poor. At present, our case reflects the phenotypic heterogeneity of leukemia. Long term follow up and evaluation of more cases is required to predict the prognostic role in our patient population.