Conventional Cytogenetic and Flow Cytometry Analysis in Pediatric Patients with Acute Lymphoblastic Leukemia (ALL) in a Brazilian Population

Leukemia is a heterogeneous group of hematologic malignancies that result from partial or total transformation of blast cells. Acute lymphoblastic leukemia (ALL) is the most common malignancy in childhood, especially in white males under the age of 14 years. Several criteria can be adopted to classify the disease, including the morphology, cytochemistry, immunophenotyping and cytogenetic study of these cells. Cytogenetics makes it possible to detect chromosomal abnormalities and genetic leukemia cells and correlate them with the diagnosis, classification, and characterization of different stages, assessment of remission and prognosis of these neoplasms. We evaluated 30 patients aged between four months and seventeen years, with whites (50%) and males (57%) being the most prevalent. Immunophenotyping showed 93% of B-lineage ALL and 7% of early lineage T. The most frequent physical findings were lymphadenopathy (37%), hepatomegaly (77%) and splenomegaly (70%). With respect to the CBC, most patients had hemoglobin below 10 g / dl (73%), leukocyte count less than 10,000/μl (60%) and platelet count below 150,000/μl (83%). All these data are consistent with the literature. Hyperdiploidy was the most common chromosome abnormality observed (64%), followed by hypodiploidy (33%). Structural and / or complex numerical changes observed but not yet described in the literature, indicated poor prognosis. This study demonstrated the importance of a cytogenetic study in pediatric patients with acute lymphoblastic leukemia in Rio Grande do Norte. However, the importance of such research has yet to be recognized and implemented in our state.