Molecular and cytogenetic abnormalities in acute myeloid leukemia: review and case studies

Clinical outcome and prognosis of patients with acute myeloid leukemia submitted to chemotherapy with 5 years of follow-up

OBJECTIVE

The purpose of this study was to evaluate the clinical-epidemiological profile, associated risk factors and clinical outcomes of patients with acute myeloid leukemia (AML), identifying the main causes of morbidity and mortality and overall survival rate of patients at five years of follow-up.

METHOD

This was a retrospective cohort study evaluating the prognosis and clinical outcomes of 222 patients diagnosed with AML at three large hematology centers in Ceará (northeastern Brazil) over a period of five years.

RESULTS

The mean age at diagnosis was 44.1 ± 16 years, with a female prevalence of 1.3:1. No additional relevant risk factors associated with the development of AML were found, except for the well-established cytogenetic assessment. The overall 5-year survival rate was 39.4% (95%CI: 35.47 - 42.17). The main causes of death were disease progression (37.72%; n = 84) and sepsis (31.58%; n = 70).

CONCLUSION

The clinical outcomes in our sample of AML patients were similar to those of other reported groups. Disease progression and infection were the main causes of death. Access to diagnostic flow cytometry and karyotyping was greater in our sample than in the national average. As expected, overall survival differed significantly according to the risk, as determined by cytogenetic testing.

The Clinicopathological Impact of Granulocyte-Macrophage Colony-Stimulating Factor Gene Expression and Different Molecular Prognostic Biomarkers in Egyptian Acute Myeloid Leukemia Patients

Background:

Acute myeloid leukemia (AML) is characterized by clonal expansion of myeloid precursors with diminished capacity for differentiation. It develops as the consequence of a series of genetic changes in a hematopoietic precursor cell. Purpose This study aimed to investigate the correlation between GM-CSF gene expression and different molecular prognostic markers such as FLT3-ITD, NPM1 mutation A and CEBPA gene expression in 100 Egyptian AML patients. As well as, correlation with the response to induction therapy, DFS andOS in these patients.

Methodology:

Quantitative assessment of GM-CSF gene expression was performed by qRT-PCR. Additional prognostic molecular markers were determined as FLT3-ITD and NPM1 mutation A together with quantitative assessment of CEBPA gene expression by qRT-PCR.

Results:

Patients with high GM-CSF expression levels had better OS and DFS with p value 0.004 and 0.02, respectively. However, no statistically significant difference between low andhigh GM-CSF gene expression was found regarding the response to therapy (p value= 0.08). Most patients with low CEBPA expression had resistant disease together with poor OS and DFS (P value = <0.001 for each). Our results showed that patients with high CEBPA gene expression whether GM-CSF gene expression was high or low had significant higher complete remission rates (p value = 0.1 for each). However, low GM-CSF gene expression andlow CEBPA gene expression showed poor response to treatment.

Conclusion:

Our findings suggest that molecular diagnostic biomarkers for AML are an essential tool that improves prognostication andhence better patients’ management.

Overall survival of adult acute myeloid leukemia based on cytogenetic and molecular abnormalities during 5 years in a single center study

OBJECTIVES

To determined the 5-year overall survival (OS) rates for adult patients with acute myeloid leukemia (AML) patients at King Abdulaziz Medical City, Jeddah, Saudi Arabia, based on cytogenetic and molecular abnormalities. Methods:  A retrospective cohort study reviewing adult AML patient files between 2011 and 2018. Sixty-three patients were excluded due to pediatric age and secondary AML. The remaining 87 adult patients with de novo AML were enrolled in this study.

RESULTS

The most frequent cytogenetic abnormalities were t(15;17) (17.2%), followed by complex cytogenetic (13.8%) and t(8;21) (5.7%). The most frequent molecular abnormalities were promyelocytic leukemia/retinoic acid receptor alpha (PML-RARA) (16.1%) and Nucleophosmin 1 (NPM1) (11.5%). The highest OS rate was associated with t(15;17), PML-RARA, and NPM. However, complex cytogenetic was associated with the lowest OS rate; fms-like tyrosine kinase 3 (FLT3)-internal tandem duplication was independently correlated with low OS rate. Conclusion: The study describes cytogenetic and molecular abnormalities observed in adult AML patients and gives an overview of prognostic factors and determine the OS, with comparable results with recent published data by the WHO.

The detection of KIT mutations in acute myeloid leukemia

OBJECTIVE

This study describes a new method used in the clinical laboratory at Hospital Israelita Albert Einstein to detect mutations in exons 8 and 17 of the KIT gene in patients with acute myeloid leukemia.

METHODS

Genomic DNA extraction was performed on 54 samples of peripheral blood or bone marrow from patients with acute myeloid leukemia. The extracted DNA was amplified by polymerase chain reaction and sequenced, and the fragments were analyzed.

RESULTS

Within the analyzed samples, we detected four mutations in exon 8, two mutations in exon 17, and mutations or a double mutation in one sample.

CONCLUSION

The tests detecting mutations in exon 8 and 17 on the KIT gene were successfully standardized. The test is now included among the routine diagnostics employed for patients at Hospital Israelita Albert Einstein clinical laboratory.