[Clinical, molecular and cytogenetic characteristics of newly diagnosed adult acute myeloid patients with TP53 gene mutation]

Impact of TP53 alteration on allogeneic hematopoietic cell transplantation outcomes for myelodysplastic syndromes

The poor outcome of TP53 alteration has been reported in myelodysplastic syndrome (MDS) patients. However, the role of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in TP53 alteration patients remains debated. Previous studies showed that TP53 mutations had no effect on the prognosis of patients with acute leukemia after haploidentical HSCT (haplo-HSCT). The effect of haplo-HSCT on MDS patients with TP53 alterations remains to be further elucidated. We aimed to reveal the role of TP53 alterations in the prognosis of MDS patients undergoing allo-HSCT, especially haplo-HSCT. 261 MDS patients with known TP53 status were enrolled, including thirty-seven patients with TP53 mutation/deletion (TP53mut/del). TP53mut/del patients showed a worse rate of 2-year cumulative incidence of relapse (CIR) and 2-year disease-free survival (DFS) than TP53 wild type (TP53wt) patients (46.2% vs 17.0%, P < 0.001; 41.8% vs 68.9, P < 0.001) after allo-HSCT, even for those with haplo-HSCT (CIR: P < 0.001; DFS: P = 0.002). However, the prognostic effect of TP53 alteration on overall survival (OS) was not observed in patients with haplo-HSCT (66.7% vs 75.2%, P = 0.108). Positivity of post-transplantation measurable residual disease (post-MRD) and time from diagnosis to transplantation were independent risk factors for MDS patients. TP53 alterations do not affect OS in patients undergoing haplo-HSCT requires further validation.

[Clinical and prognostic values of TP53 mutation in patients with acute myeloid leukemia]

Objective: To explore the clinical and prognostic values of TP53 gene mutation in patients with acute myeloid leukemia (AML) . Methods: A retrospective analysis of 265 newly diagnosed AML patients with next-generation sequencing (NGS) data in the Hematology Department of Changhai Hospital from January 2010 to January 2019 was performed. Mutation analysis was carried out by targeted sequencing technology including 200 hematological malignancy related genes. The association of TP53 mutation with clinical features was analyzed. Results: Alterations in TP53 were found in 20 (7.5%) patients, including 17 case (6.4%) of missense mutations, 2 cases (0.7%) of frame-shift deletion mutations and 1 case (0.4%) of splicing sites mutation. A total of 23 kinds of TP53 mutations were detected, most of them (16, 69.6%) were located in the DNA binding domain of exon 5-8, 4 in the DNA binding domain of exon 3-4, 2 in exon 10 and 1 in splice site, respectively. The median age of patients with TP53 alterations was higher than those without [52 (26-72) years old vs 45 (14-75) years old, P= 0.008]. The frequency of complex karyotypes was higher in patients with TP53 alterations than those without [45.0% (9/20) vs 6.1% (15/245) , P<0.001]. Median overall survival (OS) of patients with TP53 alterations was shorter than those without[14.1 (95%CI 6.78-21.42) months vs 31.4 (95%CI 13.20-49.59) months, P=0.029]. The OS of patients treated with "Decitabine + CAG" was superior than that of patients treated with "3 + 7" regimen [30.0 (95%CI 27.35-38.84) months vs 12.5 (95%CI 5.80-19.19) months, P=0.018]. Multivariate analysis indicated that TP53, DNMT3A and USH2A alterations, WBC ≥ 12.45×10(9)/L had negative impacts on OS. Conclusion: The frequency of TP53 mutation was 7.5% in our cohort. Most mutations were located in the DNA binding domain. TP53 alterations were strongly associated with older age, complex karyotype and shorter OS. Decitabine-based induction chemotherapy and hematopoietic stem cell transplantation may improve OS, more cases and/or multicenter randomized studies are needed for further confirmation.