MECOM rearrangement involving the MYC locus: Two additional patients with the rare translocation, t(3;8)(q26.2;q24), and molecular review

Abstract

A relatively small subset of myeloid neoplasms involve rearrangements of cytoband 3q26.2. Such rearrangements are often in response to therapy and carry a poor prognosis. The ectopic expression of MECOM is the result of such translocations. To date, thirty-three t(3;8)(q26.2;q24) cases have been reported; we contribute two patients with confirmed MECOM and MYC rearrangements. Both patients presented with pancytopenia and were diagnosed with myelodysplastic/myeloproliferative disorders. In addition to translocation t(3;8), Patient 1 possessed a derivative chromosome 5, while Patient 2 possessed monosomy 7; neither patient’s clonal abnormalities resolved in follow-up studies. Of the previous 33 cases, one exhibited 5q loss, while monosomy 7 was found in fifteen. These findings contribute to the small number of reported cases with t(3;8) translocations. We also speculate about the molecular mechanisms associated with this translocation.