[Coexisting Mutations in IDH1/2-Mutated Acute Myeloid Leukemia]

Abstract

Objective: To explore the coexisting mutations in IDH-mutated acute myeloid leukemia(AML) and its relation with partial clinical parametrs.

Methods: The exon 4 mutation of IDH1/2 gene was screened by using genome DNA-PCR combined with sanger sequencing, 51 targeted gene mutations in the patients with IDH1/2 mutation were detected by using high throughput DNA sequencing combined with sanger sequencing.

Results: Among 358 patients, the IDH1/2 mutation was found in 46 cases including IDH1 mutation in 35 cases and IDH2 mutation in 11 cases, 97.87%(45/46) patients with IDH1/2 mutation simultaneously carried other gene mutations including 8(17.8%) cases with mutation of double gene, 17(37.8%) cases with mutation of 3 genes and 20(44.4%) cases with mutation of ≥ 4 genes. The mutation frequency of each patient averaged 3.52 times. In mutation of accompanied genes, the common genes were NPM1(n=29, 63.0%), next DNMT3A(n=25, 54.3%), FLT3-ITD(n=7, 15.2%), TET2(n=5, 10.9%) and NRAS(n=5, 10.9%). The average WBC level of patients with NPM1 mutation in IDH1 mutation group was higher than that of patients in wild type group(P<0.05). The complete remission (CR) rate of patients with DNMT3A mutation was significant lower than that of patients with wild type (30% vs 80%, P<0.01). The presence of ≥ 4 mutations was found to be significantly associated with higher white blood level than that in the patients with double mutations(P<0.05).

Conclusion: More than 95% AML patients with IDH1/2 mutation commonly show additional mutations. The number and the type of IDH coexisting mutations have certain effect on the clinical features and CR rate.