Cytological features of childhood acute leukemia at the Hospital de Especialidades Pediátricas, Chiapas, Mexico

Background

Childhood acute leukemia cytological features are unknown in Chiapas, Mexico. Defining these features is important because this is a relatively isolated population with high consanguinity index, and these aspects could determine differences in the response to treatment and outcome.

Methods

Eighty-one childhood acute leukemia cases treated at the Hospital de Especialidades Pediátricas (HEP) in Chiapas were characterized by morphology, immunophenotype, genotype, initial risk assignment and status at the time of the study. Results were compared with national and international relevant information.

Results

The following proportion of acute leukemia types was found: B-cell, 75.3%; myeloid, 16%; T-cell, 3.7%; B-M, 3.7% and NK cells, 1.2%. Genetic alterations were present in 40.6% of B-cell and 69% of myeloid. The genetic alteration was related to the patient's short-term evolution in type B leukemias but not in myeloid. In B-cell leukemia, the cases with the altered MLL gene died in less than one month; cases with t(1;19) (q23;p13) translocation had a good evolution, and those with t(12;21) (p13;q22) translocation had a poor evolution in the medium term. Hyperdiploidy occurred in 20% of B-cell cases; 83% of them remained in remission 1 to 12 months after diagnosis and 69% of the cases with myeloid leukemias died or abandoned the treatment at relapse after 15 days to 37 months of diagnosis.

Conclusions

The proportion of different types of acute leukemia treated at the HEP is similar to that found in other parts of the country. Their behavior and outcome are related to the presence or absence of specific and non-specific genetic alterations.