DNA Quantitation in Pediatric Acute Leukemia

Abstract

background: Deoxyribose Nucleic Acid (DNA) ploidy, and immunophenotyping are now established as prognostic markers, however provide vulnerable information regarding long term outcome of acute leukemia.Aims of study: To establish a histochemical quantitation of nuclear DNA content of acute leukemia patients by Microspectrophotometry (MSP).Patients and methods: Prospective study on (55) patients with newly diagnosed acute leukemia from Children Welfare Teaching Hospital / Medical City Complex during the period from October 2002 to June 2003 and (10) patients with viral lymphocytosis as control group. MSP technique was used to determine the DNA content in leukemia blasts nuclei. Data were tabulated using SPSS (Statistical package for the social sciences) version 18.0 for windows. P-values equal or less than 0.05 were considered significant.Results: DNA cytochemical quantitation was studied after applying Feulgen stain. The amount of DNA per nucleus were expressed as means optical density × 10-3. The results showed that the mean DNA value was (0.545) while that of control group was (0.418). The ALL group was shown to have significantly higher mean OD compared to other groups.The frequency distribution of the different groups shows that there is homogeneous population of the mean OD of Feulgen stained nuclei for the control, AML, and AUL groups while it shows a heterogeneous population for ALL group. In comparison with the range of OD of nuclei of the control group, leukemia cases can be differentiated into diploid and aneuploidy classes. DNA aneuploidies were identified in (12/55) cases analyzed, thus accounting for (21.8%). For the ALL group, the mean OD readings in (18) patients (60%) were within the diploid region while (12) were outside the range (aneuploidy type) (40%).Conclusions: DNA quantitation determined by MSP may represent an additional factor to improve the definition of risk groups of acute leukemia, it will continue to be a valuable tool for understanding tumor growth heterogeneity.