Flow Cytometric Analysis: Four-Year Experience in a Tertiary Care Centre of Pakistan

PURPOSE   This study summarizes a four-year experience from the analysis of hematolymphoid malignancies in Pakistani population using a database of six-colored flow cytometry. METHODS A cross-sectional survey of 323 specimens of hematolymphoid malignancies using six-colored flow cytometry (FC) was carried out in Shifa International Hospital, Islamabad, Pakistan from June 2012 to June 2016. The criterion for specimen adequacy was that the cases have abnormal populations by FC, and the specimen age (time from biopsy to being examined by the six-color FC tube) of three days or less was to be included in the study. Clinical follow-up of greater than six months was required for a negative flow cytometric study without a subsequent biopsy. Data analysis was done using  Statistical Package for the Social Sciences (SPSS) version 21. One-way analysis of variance (ANOVA) was used to compare diagnosis with some antibodies used. RESULTS   The number of specimen within certain age groups included were: 0-15 years; 111 (34.3%), 16-30 years; 65 (20.12%), 31-45 years; 47 (14.5%), 46-60 years; 46 (14.2%) and ≥ 60 years; 54 (16.7%). Hematological malignancies were documented in descending order of sequence with B-cell acute lymphoblastic leukemia (27.9%), acute myeloid leukemia (26.3%), chronic lymphocytic leukemia (13.3%), T cell acute lymphoblastic leukemia (7.7%), non-Hodgkin's lymphomas (5%), hairy cell leukemia (1.9%), chronic myeloid leukemia (0.3%), paroxysmal nocturnal hemoglobinuria (0.6%) and plasma cell dyscrasias (0.6%). The mean number of antibodies used were 12.68 ± 2.97. One-way ANOVA was used to compare diagnosis with some antibodies used. Statistical significance was found between diagnosis and number of antibodies used (F= 5.23 p<0.001). CONCLUSION   B cell acute lymphoblastic leukemia is most commonly diagnosed at tertiary care units in Pakistan using six-colored flow cytometry. Adoption of these complicated techniques has reinforced the need for optimization and further enhancement of flow cytometric procedures.