Trisomy 21 with t(5; 11) chromosomal translocation as new unfavorable cytogenetic abnormalities in pediatric acute myeloid leukemia type M2: One case report of nine-year follow-up and literature review.

We report one case of pediatric acute myeloid leukemia type 2 (AML-M2) who presented with karyotypic aberration of trisomy 21 with the t(5;11) chromosomal translocation. The patient achieved complete remission after two cycles of chemotherapy of daunorubicin, cytarabine and etoposide. Then, follow-up cytogenetic analysis from bone marrow cell cultures demonstrated a normal karyotype of 46, XY. After 9 years, the patient relapsed and the karyotypic abnormalities of trisomy 21 with t(5;11) reappeared. It was concluded that trisomy 21 with t(5; 11) is a new unfavorable cytogenetic aberration in AML-M2.