TOPLINE:

Allogeneic hematopoietic-cell transplantation (HCT) in second complete remission achieved 3-year overall survival of 53% and progression-free survival of 46% in adolescents and young adults with acute lymphoblastic leukemia (ALL). Measurable residual disease (MRD)-positivity and high HCT Comorbidity Index scores predicted worse outcomes.

METHODOLOGY:

• Researchers conducted a dual-center retrospective analysis at MD Anderson Cancer Center in Houston and Dana-Farber Cancer Institute in Boston, examining 164 adolescents and young adults aged 15-40 years who underwent allogeneic HCT in second complete remission between 2010 and 2022.
• Participants received either pediatric-inspired (54%) or hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone-based (33%) regimens as frontline therapy, with 74% undergoing myeloablative conditioning and 67% achieving MRD-negative status prior to transplantation.
• Analysis included assessment of overall survival, progression-free survival, cumulative incidence of relapse, and nonrelapse mortality, with a median follow-up of 36 months in survivors.

TAKEAWAY:

• Patients with high HCT Comorbidity Index (score > 3) showed significantly worse overall survival (hazard ratio [HR], 2.7; 95% CI, 1.7-4.3; P < .001) and higher nonrelapse mortality (HR, 4.7; 95% CI, 2.2-10; P < .001).
• MRD positivity prior to transplant predicted inferior progression-free survival (HR, 2.0; 95% CI, 1.02-4; P = .04) and higher relapse risk (HR, 2.5; 95% CI, 1.2-5.1; P = .01), particularly in patients with low HCT Comorbidity Index scores.
• Female-to-male donor/recipient combinations demonstrated lower relapse risk than male-to-male combinations (HR, 0.4; 95% CI, 0.2-0.9; P = .03).
• The 6-month cumulative incidence of grades 2-4 acute graft-vs-host disease (GVHD) was 36%, while 3-year cumulative incidence of any-grade chronic GVHD reached 27%, with 37% moderate and 25% severe cases.

IN PRACTICE:

“As transplant is increasingly deferred to CR2 [second complete remission] and bridging regimens improve, understanding posttransplant outcomes in this population is essential. Our study affirms the central role of HCT in achieving durable remissions in AYA [adolescents and young adult] patients with ALL in CR2, with particularly good outcomes in patients transplanted with MRD-negative CR2 with low HCT-CI [Comorbidity Index], and provides a benchmark for future studies evaluating novel consolidation strategies in this population,” the authors of the study wrote.

SOURCE:

The study was led by Oren Pasvolsky, MD, and Shai Shimony, MD, MPH, of the MD Anderson Cancer Center. It was published online in the American Journal of Hematology.

LIMITATIONS:

According to the authors, the study has several limitations inherent to its retrospective nature, including missing data and heterogeneity in disease subtypes, treatments, conditioning regimens, and GVHD prophylaxis. Most patients did not receive posttransplant cyclophosphamide-based GVHD prophylaxis, which is now routinely used and may further reduce GVHD and nonrelapse mortality. Additionally, incomplete data regarding the clinical course prior to transplant, such as duration of first complete remission and time from relapse to second complete remission and transplant, limited certain analyses.

DISCLOSURES:

The authors received no specific funding for this work. Partow Kebriaei disclosed relationships with Jazz, KITE, and Pfizer. Additional disclosures are noted in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.