Evaluation of Clinical, Hematological and Flow Cytometry Dates in Elderly Patients with Acute Myeloid Leukemia: Impact on Clinical Outcome

BACKGROUND: Acute Myeloid Leukemia (AML) is the most frequent acute leukemia in older patients (over 60 years of age) with more than 50% of the cases, accounting for 15 to 20% of childhood leukemia and 80% of adult leukemias, with poor prognosis, especially in elderly patients. Myelodysplastic syndromes (MDS), another spectrum of clonal myeloproliferative disorders that also involve mainly older age groups and are characterized by ineffective hematopoiesis, peripheral cytopenia's, chromosomal abnormalities and predisposition for progression to AML (AML/MDS). Elderly patients with AML are part of a biological and clinically distinct group with presence of high-risk cytogenetic abnormalities, hematological abnormalities and immunophenotypic aberrations. OBJECTIVE: Evaluation of clinical, demographic, hematological and immunophenotypic parameters in elderly patients with AML and determination of correlation these parameters with disease status. METHODS: Bone marrow (BM) and peripheral blood (PB) samples from 80 elderly patients diagnosed with AML were evaluated for hematological, immunophenotypic and karyotype parameters. The hematological parameters evaluated were: count of leukocytes, platelets and blastic cells and also determination of hemoglobin levels, cytomorphologic analysis of bonne marrow, immunophenotyping by flow cytometry for immunologic AML classification, determination of aberrant lymphoid cell markers, and detection of antigens related to multidrug resistance (MDR) such us P-glycoprotein (Pgp) and multidrug resistance proteins type 1 (MRP1), p53 protein and also karyotype analysis for confirmation of AML/MDS cases. At the same time, demographic and clinical data were obtained from all patients. RESULTS: Data analysis showed that 56 patients had "de novo" AML, 6 recurrent disease, 15 transformed MDS and 3 refractory AML. In relation to clinical aspects, there was a predominance of splenomegaly (91.2%), followed by hepatomegaly (76.2%). Laboratory findings showed a predominance of hyperleukocytosis (91.3%), thrombocytopenia (85%) and anemia (86.2%), with cytopenias being more pronounced in cases of AML/MDS. Most cases were classified as FAB M1 (36.6%), M2 (17.5%) and M4 (23.7%). Our data analysis was statistically significant (p < 0.05) and showed a correlation with aberrant T-lymphoid antigens (CD3 and CD7), Pgp, MRP1, p53 protein and transferrin receptor (CD71) with the increase in the unfavorable status of the disease, contributing to a worse prognosis in these patients. CONCLUSIONS: Our results demonstrate the importance of clinical and laboratory investigations of these patients in order to obtain further information on these cancers.