ABSTRACT
Acute myeloid leukemia (AML) is a heterogeneous group of disorders with regards to its pathology and molecular genetics features. The translocation t(8;21)(q22;q22), which results in the fusion of the AML and ETO genes, is a recurrent aberration in AML, preferentially correlated with FAB- M2, and has the highest incidence in childhood AML. Because of the favorable prognosis, the evidence of the t(8;21) or the AML1-ETO fusion gene is mandatory in most of the therapy trials, allowing the stratification of the patients to the correct risk group in terms of treatment. Here, we describe a novel case of sole translocation t(10;19)(p11.2;p13) in a AML1-ETO negative AML-M2 patient. In general, this translocation is previously observed with combination of complex translocations, but sole abnormality was not previously observed. This is a novel translocation and not observed previously as a sole abnormality in any AML case. Hence, the functional role of this translocation is still unknown. Short term bone marrow culture was carried out for conventional cytogenetics and karyotype was 46, XX,t(10;19)(p11.2;p12) in all 20 metaphases analyzed. To confirm this translocation FISH with Whole chromosome paint probe was applied and results confirmed the translocation between chromosome 10 and 19. To the best of our knowledge, this is the first novel case of sole t(10;19) in a paediatric AML-M2 patient with AML-ETO negative fusion. Patient expired within a week. Therefore, the present case challenges the view that the occurrences of sole and new novel translocation require more such cases to be studied in large cohort which is generally an indication for poor prognosis.
ABSTRACT
Trisomy of chromosome 8 is frequently reported in myeloid lineage disorders and also detected in lymphoid neoplasms as well as solid tumors suggesting its role in neoplastic progression in general. It is likely to be a disease-modulating secondary event with underlying cryptic aberrations as it has been frequently reported in addition to known abnormalities contributing to clinical heterogeneity and modifying prognosis. Here, we share our findings of trisomy 8 in leukemia patients referred for diagnostic and prognostic cytogenetic assessment. Total 60 cases of trisomy 8, as a sole anomaly or in addition to other chromosomal aberrations, were reported (January 2005–September 2008). Unstimulated bone marrow or blood samples were cultured, followed by GTG banding and karyotyping as per the ISCN 2005. Patients with +8 were chronic myeloid leukemia (CML) (36), acute myeloid leukemia (AML) (17), and acute lymphoblastic leukemia (ALL) (7). In 7 patients, trisomy 8 was the sole anomaly, whereas in 6 patients +8 was in addition to normal clone, in 47 patients, the +8 was in addition to t(9;22), t(15;17), and others, including 3 with tetrasomy 8. Only one patient showed constitutional +8. The present study will form the basis of further cumulative studies to correlate potential differential effects of various karyotypic anomalies on disease progression and survival following a therapeutic regime. To unravel the role of extra 8 chromosome, constitutional chromosomal analysis and uniparental disomy will be considered.