Chromosomal Abnormalities in Acute Myeloid Leukemia Patients of Orissa and Their Prognostic Implications

Abstract

Summary Chromosomal abnormalities in 55 AML patients from Orissa (India) were studied. Of them, 12 patients had only abnormal metaphases (AA), 41 patients had both normal and abnormal metaphases (AN) and the rest 2 patients exhibited only normal metaphases (NN). Basing on the number of chromosome all the patients were classified into 5 sub-groups like (1) normal diploidy with 46 chromosomes in 2 patients, (2) pseudodiploidy group with 46 chromosomes and some structural abnormalities in 4 patients, (3) hypodiploid group with Ͻ46 chromosomes in 37 patients, (4) hyperdiploidy-A group with 47 to 50 chromosomes in 8 patients and hyperdiploidy-B group with Ͼ50 chromosomes in 4 patients. Primary translocations like t(8, 21), t(1, 14), t(9, 22) were detected in 8, 1 and 7 patients respectively. In addition, secondary aberrations were also observed in 36 patients. These secondary aberrations were mostly unstable and nonclonal ones which were present singly or in various combinations. Maximum number of patients achieved complete remmission (CR) from AN subgroup (46.3%) hyperdiploidy-B group (100%), patients with t(8; 21) translocation (75%), patients with trisomy 22 and patients with no secondary aberrations. This study suggests that hyperdiploidy, t(8, 21), trisomy 8, presence of both normal and abnormal metaphases and absence of secondary aberrations are the favourable prognosticators while presence of only abnormal metaphases, presence of more than one secondary aberration, t(9, 22) translocation, hypodiploidy and monosomy 7 are unfavourable prognosticators.