Specific chromosomal changes in patients with acute nonlymphocytic leukemia from India

Abstract

SUMMARYWe analysed forty consecutive patients with acute nonlymphocytic leukemia (ANLL) using methotrexate cell synchronization and 24 h-unstimulated cultures of bone marrow cells to determine the incidence of chromosomal aberrations and the association of specific anomalies with FAB morphological subtypes, in an Indian population. All patients demonstrated an abnormal karyotypic pattern. The specific chromosomal changes viz., t(9;22), t(8;21), t(15;17), t/del(l lq), 12p-were found in M1(3/5), M2(8/15), M3(8/8), M4(1/1) M5(2/4) and M2Ba(l/l) (M2 with Basophilia) patients. Abnormalities of I l q were also noted in two M2 patients showing monocytic involvement. A translocation involving chromosomes 6 and 9 was seen in one patient with M 1 and two patients with M2. An inv( 16) was observed in MI (one case), M2 (two cases) and M6 (one case). A del(16) was noted in an M4 case. Although t(9;22) is frequently associated with M1 patients, it was also detected in M2 (two patients) and M4 (one patient). Among all the FAB specific anomalies described above, t(8;21) and t( 15;17) were observed only in M2 and M3 patients, respectively. Interestingly, one M2 patient had two independent clones, one with t(8;21) and t(9;ll). Deletion or translocation involving 1 lq was found in a Ph positive M4 patient. New structural rearrangements such as t(1;7) (q32;q36) in association with t(8;21), and t(14;22) (q32;qll) in association with del(1 l)(q23) were detected in a M2 and a M5 patient, respectively. In conclusion, our studies have revealed that the incidence of FAB specific abnormalities viz., t(8;2 1); t(15;17), t(9;22), t/del(llq) and also other recurrent anomalies viz., -7/7q-, + 8 is much higher in our patients, as compared with other countries. This difference may be attributed to the influence of differential environmental exposure to unknown carcinogenic agents.

Distribution and features of hematological malignancies in Eastern Morocco: a retrospective multicenter study over 5 years

“…This distribution was comparable to that reported in China [ 81 ]. The predominance of M2 was also observed in Iran, India, Germany, USA and Singapore [ 82 – 86 ].…”

Mutations of NPM1 gene in de novo acute myeloid leukaemia: determination of incidence, distribution pattern and identification of two novel mutations in Indian population

“…Moreover, at the present time, no data exist in India with respect to the incidence and distribution pattern of NPM1 mutations, despite the fact that AML is one of the most common haematologic malignancies associated with the greatest mortality and morbidity in this country. Notably, Indian patients appeared to develop acute leukaemia at much younger ages than those in the west, with the median age at onset ranging between 27 and 30 years only [25,26]. Genotypic analysis of the NPM1 gene may help to elucidate the molecular pathogenesis of AML that arises in this population.…”

Emergence of an unrelated highly aberrant clone in an AML patient at relapse four months after peripheral blood stem cell transplantation

“…Aberrations of 5q frequently occur as secondary aberrations in patients with AML. [1011] Except MDS, aberrations of 5q generally occur as a part of the complex karyotype in de novo AML. [61112] Post-chemotherapy remission marrow showed the persistence of a dic(5q) clone along with a major normal diploid clone.…”