Clinical and Genomic Profiles of Korean Patients with MECOM Rearrangement and the t(3;21)(q26.2;q22.1) Translocation

The translocation (3;21)(q26.2;q22.1) is a unique cytogenetic aberration that characterizes acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) in patients with AML and myelodysplastic syndrome (MDS) or a therapy-related myeloid neoplasm. Using multigene target sequencing and FISH, we investigated the clinical and genomic profiles of patients with t(3;21) over the past 10 years. The frequency of t(3;21) among myeloid malignancies was very low (0.2%). Half of the patients had a history of cancer treatment and the remaining patients had de novo MDS. Twenty-one somatic variants were detected in patients with t(3;21), including in CBL, GATA2, and SF3B1. Recurrent variants in RUNX1 (c.1184A>C, p.Glu395Ala) at the same site were detected in two patients. None of the patients with t(3;21) harbored germline predisposition mutations for myeloid neoplasms. MECOM rearrangement was detected at a higher rate using FISH than using G-banding, suggesting that FISH is preferable for monitoring. Although survival of patients with t(3;21) is reportedly poor, the survival of patients with t(3;21) in this study was not poor when compared with that of other AML patients in Korea.

Automated summary

This study investigated the clinical and genomic profiles of patients with t(3;21) translocation in the past 10 years. The frequency of t(3;21) in myeloid malignancies was very low and most of the patients had a history of cancer treatment. Somatic variants were detected in these patients, but no germline predisposition mutations for myeloid neoplasms were found. Compared to other AML patients in Korea, the survival rate of patients with t(3;21) was not poor.