Allogeneic hematopoietic cell transplantation in patients with therapy-related myeloid neoplasm after breast cancer: a study of the Chronic Malignancies Working Party of the EBMT

Outcomes with Allogeneic Hematopoietic Stem Cell Transplantation in Therapy Related Myeloid Neoplasms: A Systematic Review and Meta-Analysis

Therapy-related myeloid neoplasms (t-MN), which include acute myeloid leukemia (t-AML), myelodysplastic syndrome (t-MDS), and myelodysplastic/myeloproliferative neoplasms are secondary malignancies occurring as a late complication following chemotherapy or radiation therapy for an antecedent disorder. Allogeneic hematopoietic stem cell transplant (allo-HCT) is a potentially curative treatment option in t-MN patients. This systematic review and meta-analysis aimed to explore the outcomes of allo-HCT in t-MN. Following PRISMA guidelines, a comprehensive literature search was performed on PubMed, Cochrane, and Clinicaltrials.gov. Survival data were extracted from Kaplan-Meier curves to calculate overall survival (OS) and disease-free survival (DFS) probabilities. A total of 7785 (t-AML: 67.3%, t-MDS: 26.5%, and mixed presentation: 6%) patients from 33 original studies reporting outcomes of allo-HCT in t-MN patients were included for analysis. The patients age ranged from 2 to 89 years, and 61.7% were female. The pooled median OS was 16.9 months (95% CI: 13.7-21.1), whereas the estimated mean OS was 46.0 months (95% CI: 42.1-49.6). The pooled median DFS was 8.8 months (95% CI: 7.4-11.2), and the mean DFS was 35.5 months (95% CI: 33.4-41.9). The pooled proportion of acute graft-versus-host disease (aGvHD) was 34% (95% CI: 0.35-0.45, I²: 91.71%, P < .0001). Relapse of the myeloid neoplasm was the most common cause of mortality, followed by infections, relapse of the underlying disease, and GvHD. Despite these challenges, allo-HCT remains a potential treatment option with promising outcomes for carefully selected t-MN patients.

Allogeneic hematopoietic cell transplantation for therapy-related myeloid neoplasms arising following treatment for multiple myeloma: a retrospective study on behalf of the Chronic Malignancies Working Party of the EBMT

Therapy-related myeloid neoplasms (t-MN) are a complication of multiple myeloma (MM) treatment. Our retrospective, EBMT registry study included 157 such patients allografted (allo-HCT) between 2006 and 2018. Most patients (130) had a prior autologous HCT. Fifty-seven (36.4%) were transplanted for t-AML and 100 (63.6%) for t-MDS. Median times from MM and t-MN diagnoses to allo-HCT were 72.6 (interquartile range (IQR), 46.1-102.9) and 6.4 (IQR, 3.9-9.4) months. Fifty-eight (38.4%) t-MN patients were in complete remission (CR) at allo-HCT predominantly conditioned with reduced intensity (70.3%). With a median follow-up of 64.9 (95% CI: 39-76) months, relapse incidence (RI) from MM at 1 and 5 years was 4% (0-10%) and 12% (2-22%), respectively, with few deaths (n = 3) only due to MM disease progression, whereas t-MN RI and non-relapse mortality (NRM) at 1 and 5 years were 35% (95% CI 28-43%) and 45% (95% CI: 36-53%) and 20% (95% CI 13-26%) and 31% (95% CI: 23-39%). Overall survival (OS) and progression-free survival (PFS) estimates at 1 and 5 years were 55% (95% CI: 47-63%) and 27% (95% CI: 19-35%) and 45% (95% CI 36-53%) and 24% (95% CI 16-32%). Older (>65 years) t-MN patients with high-risk cytogenetics do not benefit from allo-HCT.

Allogeneic haematopoietic cell transplantation for therapy-related myeloid neoplasms arising following treatment for lymphoma: a retrospective study on behalf of the Chronic Malignancies Working Party of the EBMT

Therapy-related myeloid neoplasms (t-MN), either myelodysplastic neoplasms (t-MDS) or acute myeloid leukemias (t-AML), have a poor prognosis and allogeneic haematopoietic cell transplantation (allo-HCT) represents the only curative option. In this multicenter, registry-based study, we analyzed outcomes of 378 patients undergoing first allo-HCT between 2006-2017 for t-MN arising secondary to lymphoma treatment. Median age was 58 years at allo-HCT; 222 (59%) had a diagnosis of t-MDS and 156 (41%) of t-AML, respectively. At the time of allo-HCT, 46% of t-MN cases were reported as in complete remission (CR) and 15% of lymphomas were recorded as not in remission. A reduced intensity conditioning regimen was used in 70% of cases. For the entire cohort, 5-year OS, and t-MN PFS, relapse incidence and NRM were 32%, 28%, 35% and 37%, respectively. In multivariable analysis, undergoing allo-HCT with t-MN not in CR and older age were associated with significantly worse OS, PFS and NRM. At 5 years post allo-HCT, the relapse incidence of lymphoma was low at 3%, while the rate of secondary malignancies was 8%. This analysis shows the curative potential of allo-HCT for patients with t-MN arising secondary to lymphoma treatment in approximately a third of patients.

Acute Myeloid Leukemia Post Cytotoxic Therapy in Breast Cancer Survivors-Over 23 Years of Single Center Analysis

Background: Acute myeloid leukemia post cytotoxic therapy (AML-pCT) among breast cancer (BC) survivors represents a life-threatening complication. This study aims to assess the clinical outcomes of AML-pCT post BC. Methods: An analysis of all AML patients treated at a single hematology center (2000-2023) was performed to select patients with AML-pCT post BC. We applied the 2022 ELN criteria to define the genetic risk. Results: Among 847 AML patients, 28 were diagnosed with AML-pCT following BC. Complex karyotype (CK) occurred in 23.8% of patients. The median overall survival (OS) was 40 months. The survival outcomes were better after allogenic hematopoietic stem cell transplantation (alloHCT) treatment compared to chemotherapy alone (median OS: 47 versus 7 months, p = 0.008). Patients demonstrating CK showed lower survival compared to those without CK (2-year OS: 25.0% versus 66.2%, p = 0.0048). The multivariable Cox proportional hazards regression model indicated that treatment with alloHCT emerged as a significant factor associated with improved OS. The treatment was associated with superior OS (HR = 0.07, 95% CI = 0.01-0.86, p = 0.04). Conclusions: Patients with AML-pCT following BC were characterized with the highest frequency of adverse genetic risk profiles and demonstrated worse survival rates. AlloHCT should be performed as early as possible in such patients. The growing need for studies on inherited cancer susceptibility underscores the importance of close AML-pCT development monitoring in BC survivors.

Therapy-related myelodysplastic syndromes in the genomics era

Therapy-related myelodysplastic syndromes (t-MDS) represent a heterogeneous group of malignancies that arise as a late complication of prior exposure to chemotherapy and/or radiotherapy administered for a primary condition. T-MDS account for approximately 20% of all MDS and are characterized by resistance to current treatment strategies and poor prognosis. Our understanding of t-MDS pathogenesis has considerably improved over the last 5 years with the availability of deep sequencing technologies. T-MDS development is now considered as a multifactorial process resulting from complex interactions between an underlying germline genetic susceptibility, the stepwise acquisition of somatic mutations in hematopoietic stem cells, the clonal selection pressure exerted by cytotoxic therapies, and alterations of the bone marrow microenvironment. The survival of patients with t-MDS is generally poor. This can be explained by both patient-related factors including poor performance status and less tolerance to treatment and disease-related factors, such as the presence of chemoresistant clones, high-risk cytogenetic alterations and molecular features (e.g. high frequency of TP53 mutations). Around 50% of t-MDS patients are classified as high/very high risk based on IPSS-R or IPSS-M scores, versus 30% in de novo MDS. Long-term survival is only achieved in a minority of t-MDS patients who receive allogeneic stem cell transplantation, but the development of novel drugs may open new therapeutic opportunities, especially in unfit patients. Further investigations are needed to improve the identification of patients at higher risk of developing t-MDS and determine whether primary disease treatment can be modified to prevent the occurrence of t-MDS.