Chronic lymphoproliferative disorders at an Indian tertiary cancer centre - the panel sufficiency in the diagnosis of chronic lymphocytic leukaemia.

BACKGROUND: Flow cytometry has come to occupy the vanguard of the high through put diagnostic techniques that have been used to differentiate between various chronic lymphoproliferative disorders (CLPD). However, economic considerations have created the need for minimal consensus panels that can yield maximum information at reasonable costs. AIMS: To collect, analyse and correlate the morphologic, immunophenotypic, and the cytogenetic data from the cases of chronic lymphoproliferative disorders, which were diagnosed at an Indian speciality cancer centre. METHODS AND MATERIAL: The morphology was recorded after staining the samples with the Leishman or the MGG stains. The lineage assignment was done by using three colour flow cytometry with a primary panel of antibodies. For the cytogenetic studies, the short term culture of the sample cells were arrested by using colcemid and they were G-banded by using trypsin and Giemsa stain. FISH studies were conducted by using a CLL-specific diagnostic kit. RESULTS AND
CONCLUSIONS: A total of 66 cases were evaluated, which had a median age of 64.5 years and a sex ratio of 2.3:1. Of these 66 cases, 40 cases were of CLL and 9 cases were of atypical CLL. 17 cases were classified as CLPD and these included 13 cases of Non-Hodgkin's Lymphoma, two cases of Hairy Cell Leukaemia, one case of Follicular Lymphoma and one case of Prolymphocytic Leukaemia. In immunophenotyping, the lack of expression of CD22 had the highest correlation with a definitive diagnosis of CLL. Cytogenetics demonstrated a classical follicular lymphoma abnormality, t (14; 18) (q32; q21), in one case. A basic minimal panel is sufficient for the routine diagnosis of CLL. However, the stratification of CLPD requires the use of more extensive panels.