A Pediatric Acute Promyelocytic Leukemia With a Rare Karyotype of ider(17)(q10)t(15;17) and Favorable Outcome

Abstract

Acute promyelocytic leukemia (APL) is a specific malignant hematological disorder with a diagnostic hallmark of chromosome translocation t(15;17)(q22;q21). As a very rare secondary cytogenetic aberration in pediatric APL, ider(17q) (q10)t(15;17) was suggested to be a poor prognostic factor based on previous case reports.Here, we report a pediatric APL case with a rare karyotype of ider(17)(q10)t(15;17). Bone marrow aspiration, immunophenotyping, molecular biology, cytogenetic, and fluorescence in situ hybridization (FISH) analyses were performed at initial diagnosis and during the treatment.A 6-year-old boy was brought to our hospital with the chief complaint of bleeding gums twice and intermittent fever for 3 days in January 2013. He was diagnosed as low-risk APL according to the 2012 NCCN guideline on APL, with the expression of PML-RARA (bcr3 subtype) and the karyotype of 46,XY, der(15)t(15;17)(q22;q21),ider(17)(q10)t(15;17), which was further verified by FISH. The patient was treated through combination all-trans retinoic acid (ATRA) and arsenic with daunorubicin according to the 2012 NCCN guideline for APL. Continuous hematological completed remission (HCR) and major molecular remission (MMR) were achieved with normal karyotype for >28 months after induction chemotherapy.Different from previously reported cases, this pediatric APL patient with ider(17)(q10)t(15;17) displays favorable clinical outcomes, which might be related to the low-risk classification and arsenic treatment during the treatment. It suggests that ider(17)(q10)t(15;17) may not be the sole determinant for worse outcomes in pediatric APL and implies that more contributed factors should be considered for pediatric APL prognosis.

Treatment Outcome and the Genetic Characteristics of Acute Promyelocytic Leukemia in Children in Poland From 2005 to 2018

“…Variant translocation described as simple translocation involving chromosome 15 or 17 with any other chromosomes or complex translocations characterized by the involvement of additional chromosomes in addition to chromosomes 15 and 17 (4)(5)(6)(20)(21)(22)(23)(24) was found in two patients in the analyzed group. In one of them, t(11;17) (q23;q12) was identified, and in the second complex, translocation involving chromosomes 4, 15, 16, and 17 was found.…”

A rare case of acute promyelocytic leukemia with ider(17)(q10)t(15;17)(q22;q21) and favorable outcome

“…Some reports suggested that ider(17)(q10)t(15;17) (q22;q12) might be a poor prognostic factor in APL [1,3,[12][13][14][15]. Therefore, some reports showed that the clinical course of patients with ider(17)(q10)t(15;17) (q22;q12) did not seem to differ from that of the typical t(15;17)(q22;q12) [13,15]. The role of ider(17)(q10)t(15;17)(q22;q12) in APL is still an ongoing investigation and is limited by the small number of published cases.…”

Biased Clonal Evolution in Acute Promyelocytic Leukemia through Imbalances Affecting the der(17) but Not the der(15) Chromosome: Report of Two Cases

“…Whenever an ider(17q) is generated as a secondary mutation, not only the genetic information contained in the long arm is duplicated, but also genes from the short arm are lost, as is the case for the tumor suppressor gene TP53, among others. Significance of the ider(17q) in APL severity at diagnosis, response to treatment, or overall survival is still uncertain and limited by its low incidence [Schoch et al, 1996;Chou et al, 1997;Kaleem et al, 1999;Xu et al, 2001;Manola et al, 2010;Kim et al, 2011;Hu et al, 2014;He et al, 2015;Liu et al, 2020]. We here present two cases with APL who acquired an ider(17q) as a secondary chromosomal change.…”