Background: T lymphoblastic leukaemia (T ALL) carries a worse prognosis compared to B lymphoblastic leukaemia (B ALL) especially in children. There are only a few published data about immunophenotype of T ALL in India. So we studied the immunophenotypic pattern of T ALL in children by flow cytometry and correlated it with clinical and pathological factors.

Materials and Methods: 271 consecutive cases of paediatric acute leukaemias reported in the Regional Cancer Centre, Thiruvananthapuram, Kerala, were immunophenotyped by flow cytometry and clinic-pathological analysis was done in all cases. The study period was from June 2009-June 2011. T ALL cases were followed up for two and a half years till the completion of treatment.

Result: Among the 271 cases of myeloperoxidase negative acute leukaemia, 232 were B-ALL, 39 were T-ALL. Among 39 cases of T ALL, 25 cases (64%) were CD34 positive and 14(35.8%) were CD34 negative. Of the 25 CD34 positive cases, only 12 (48%) completed treatment compared to 10 out of 14(71%) CD34 negative cases.

Conclusion: The occurrence of CD34 positivity in T ALL is high in children coming to our centre from different parts of Kerala which is in contrast to western studies. Even though T ALL is treated under high risk protocol, CD34 positive cases need special attention and they should undergo molecular studies to detect the bad prognostic factor.

Keywords: T lymphoblastic leukaemia, CD 34,flow cytometry.

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Dr Sindhu Nair.P

Assistant Professor, Department of Pathology, Regional Cancer Centre, Trivandrum, Kerala, India 695024

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