Impact of treatments before allogeneic hematopoietic stem cell transplantation in patients with higher-risk myelodysplastic syndrome

Better pre-transplant treatment options for TP53-mutated MDS: cytoreductive or non-cytoreductive therapy?

Patients with TP53-mutated myelodysplastic neoplasms (MDS) have unfavorable prognoses; the benefit of cytoreductive treatment before hematopoietic stem cell transplantation (HSCT) is debated. We retrospectively analyzed 284 MDS patients undergoing allogeneic HSCT; among which 49 had TP53 mutation, with 38 receiving cytoreduction and 11 treated exclusively with best supportive care (BSC) before transplantation. Regardless of TP53 allelic state, patients with mutated-TP53 had a lower overall survival rate and higher relapse rate than those with wild-type TP53 (P < 0.001, P = 0.002, respectively). Among the TP53-mutated cohort, the 2-year overall survival rate in the cytoreduction group was comparable to that in the BSC group (34.6% vs. 45.5%, P = 0.53), and no other prognostic benefit was observed as well (all P < 0.05). Moreover, no prognostic difference was found among the chemotherapy subgroup, hypomethylating agent subgroup, and BSC subgroup (all P > 0.05). Patients in the pre-HSCT measurable residual disease (MRD) negative subgroup, pre-HSCT MRD-positive subgroup, and BSC subgroup exhibited similar prognoses (all P > 0.05). Multivariate analyses showed that pre-HSCT cytoreduction was not associated with post-transplant survival (all P > 0.05). In conclusion, TP53-mutated MDS patients have poor post-HSCT outcomes; compared to BSC, pre-HSCT cytoreduction doesn't improve prognosis, even in those with MRD negative before transplantation.

Allogeneic stem cell transplantation without preconditioning in a child with therapy-related myelodysplastic syndrome: A case report

RATIONALE

Infants with mixed-lineage leukemia (MLL)-rearranged leukemia are usually refractory to standard induction therapy and are not immediate candidates for allogeneic hematopoietic stem cell transplantation (allo-HSCT). Chromosome 11q23 translocations, resulting in MLL rearrangement, have been well characterized in infant acute lymphoblastic leukemia (ALL). While t(4;11) ALL continues to have carry a bleak prognosis, patients with therapy-related myelodysplastic syndrome (t-MDS) have a shorter median overall survival than those compared with de novo MDS.

PATIENT CONCERNS

We describe a child with t-MDS who evolved from MLL-rearranged ALL and was successfully treated with HSCT without toxic preconditioning.

DIAGNOSES

MDS diagnosis was based on morphological characteristics of bone marrow dysplasia in patients with clinical manifestations evidence of hematopoiesis impairments by different combinations of anemia, leukopenia, neutropenia, and thrombocytopenia.

INTERVENTIONS

Although the best donor for allo-HSCT is generally considered an human leukocyte antigen-matched sibling, only ~ 30% of patients have a suitable sibling. HSCT from an unrelated donor is a suitable option for patients with t-MDS who do not have matched sibling donors.

OUTCOMES

Allo-HSCT without recipient preconditioning could be a promising treatment option for t-MDS, especially for patients with recurrent or persistent infections.

LESSONS

Cytogenetics, prognosis, and treatment of t-MDS are briefly discussed. Preconditioning before allo-HSCT seriously damages immune function. This work reviews our experience with a patient with t-MDS following ALL complicated by recurrent infections, and highlights our choice to omit preconditioning from allo-HSCT.