|The following article features coverage from the American Society of Hematology 2020 meeting. Click here to read more of Hematology Advisor‘s conference coverage.|
For patients with hematologic malignancies undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT), certain inherited and acquired hematologic and immunologic-related gene variant profiles may negatively affect outcomes, according to study results presented by Li Zhihui, MD, of Beijing Boren Hospital, Beijing, China, at the virtual 62nd American Society of Hematology (ASH) Annual Meeting and Exposition.
To evaluate the influence of genetic variants on patient outcomes following allo-HSCT, investigators conducted whole exome sequencing of DNA extracted from bone marrow samples from 164 patients with hematologic malignancies who underwent allo-HSCT at the Beijing Boren Hospital from January 2018 to June 2020.
Median patient age was 14 years (range, 1-67), and diagnoses included acute myeloid leukemia (n=68; 41.5%), acute lymphoblastic leukemia (n=67; 40.8%) and non-Hodgkin lymphoma (n=29; 17.7%). Prior to undergoing allo-HSCT, 29.9% patients were in first complete remission (CR), 38.4% of patients were in second CR, 13.4% were in partial remission, and 18.3% were not in remission. Among donors, 76.2% were haploidentical family members, 11.0% were identical siblings, and 12.8% and unrelated volunteers.
After a median follow-up duration of 12.6 months (range, 11.2-17.0), 105 patients (64.0%) achieved durable remission following allo-HSCT, 47 patients (28.7%) experienced relapse, and 12 patients (7.3%) died.
Exome sequencing, validated by Sanger sequencing, revealed 191 genetic variants in genes related to immunodeficiency, with an average of 3.5 variants per patient (range, 0-10). Recurrent variants (defined as being identified more than 6 times) were found within 26 of these genes. Furthermore, variants within IFIH1and IL10RB were associated with post-transplant relapse (P =.006, and P =.007, respectively). Additionally, variants in genes related to hemophagocytic lymphohistiocytosis (HLH) were identified in 9 patients (5.5%), and variants in genes related to Fanconi anemia were identified in 11 patients (6.7%).
A significantly greater incidence of acute graft-vs-host disease and/or infection was noted among patient with HLH-related or Fanconi anemia-related gene variants compared with patients who did not have these gene variants (P =.019).
The investigators also identified 153 variants within known tumor-associated genes, with an average of 1.93 variants per patient (range, 0-16). Recurrent variants (defined as being identified more than 4 times) were found within 17 of these genes, and variants within TP53, KRAS, and NUDT15 were associated with post-transplant relapse (P =.000025, P =.0082, and P =.000018, respectively).
“Our results indicate that the patients with hematological malignancies carried both inherited and acquired hematological and immunological-related gene variant profiles,” concluded Dr Li.
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Li Z, Zhao Y, Song Y, et al. Influence of inherited and acquired hematological and immunological gene variants on the outcomes of allogeneic hematopoietic stem cell transplantation in patients with hematological malignancies. Presented at: American Society of Hematology (ASH) 62nd Annual Meeting and Exposition; December 5-8, 2020. Abstract 493.