Among communities in which consanguineous marriages are commonplace, nonsibling matched donor transplants may represent a viable option for patients with beta-thalassemia, according to research published in Hemoglobin. Type of transplant in this setting may not, therefore, affect overall survival (OS) or disease-free survival (DFS).
Allogeneic hematopoietic stem cell transplantation (HSCT) remains the only treatment with curative potential for many patients with hematologic disorders, including beta-thalassemia. Although the use of human leukocyte antigen (HLA)-matched sibling donors may yield the best results, such donors are available in less than one-third of cases.
HLA registries have improved the rate at which matched unrelated donors (MUDs) are used, but ethnographic research suggests that in some societies — such as those in which consanguineous marriage is common — the chances of finding a fully matched nonsibling family donor (MFD) are higher. For this study, researchers evaluated outcomes among a group of patients from a community with a high rate of consanguineous marriage who underwent HSCT for beta-thalassemia.
Overall, data from 86 HSCTs, which were performed on 82 patients with transfusion-dependent thalassemia, were reviewed. Patients were grouped based on transplant donor-type: MFD (14 patients; 16%), MSD (48 patients; 56%), and MUD (24 patients; 28%). In the MFD, MSD, and MUD groups, the median ages were 4.5, 7.5, and 6.5 years; 9, 24, and 14 patients were male; 7, 23, and 12 patients were Pesaro risk class 1 or 2; and 7, 25, and 12 were Pesaro risk class 3, respectively.
Treatment-related complications occurred at a similar rate between the 3 groups, including grade 2 to 4 graft-vs-host-disease (3 [21%] in the MFD group, 4 [21%] in the MSD group, and 2 [8%] in the MUD group; P = .342). No difference was observed in the mean number of transfused CD34+ cells or in the median number of days by which neutrophil and platelet recovery were reached. Transplant-related mortality was also similar between the 3 groups.
Graft type did not predict for DFS or OS, although age, gender, and Pesaro risk class were predictive of DFS and OS in both univariate and multivariate analysis. Pesaro risk class (hazard ratio for DFS, 4.4; P = .007; hazard ratio for OS, 3.0; P = .021) appeared to be the strongest predictor of outcomes on univariate analysis.
Aydogdu S, Toret E, Aksoy BA, et al. Comparison of hematopoietic stem cell transplantation results in patients with β-thalassemia major from three different graft types. Hemoglobin. Published online January 21, 2021. doi:10.1080/03630269.2021.1872611