GVHD Is Less Common in Hispanic Patients With MPN Than Non-Hispanic White Patients

Hispanic patients had a significantly lower cumulative incidence of chronic graft-versus-host disease (GVHD) than non-Hispanic White patients in a retrospective analysis of those with myeloproliferative neoplasms (MPNs) who underwent hematopoietic cell transplantation (HCT). The research was presented at the 2022 American Society of Clinical Oncology Annual Meeting.

The study analyzed transplant-related outcomes in 38 patients who underwent HCT for MPN between January 2008 and December 2020 at a large hospital in San Antonio, Texas.

The analysis included 19 Hispanic patients and 19 non-Hispanic White patients. Myelofibrosis was the most common (n = 19) form of MPN, followed by chronic myelomonocytic leukemia (n = 12) and myelodysplastic/myeloproliferative neoplasms, unclassifiable (n = 7). There were no significant differences in performance status, conditioning regimen, stem cell source, or GVHD prophylaxis between Hispanic and non-Hispanic White patients. Hispanic patients were significantly more likely to have a haploidentical donor (47%) than non-Hispanic White patients (11%; P<.001).

The cumulative incidence of chronic GVHD was significantly greater in non-Hispanic White (68%) patients than in Hispanic (37%) patients (P=.03). The cumulative incidence of grade 1/2 and grade 3/4 acute GVHD was not significantly different between non-Hispanic White (50% and 50%, respectively) patients and Hispanic (40% and 60%, respectively) patients (P=.5 and P=.4, respectively).

The median overall survival was not significantly different between non-Hispanic White (6.75 years) patients and Hispanic (2.67 years) patients (P=.08).

A total of 5 non-relapse deaths were reported in non-Hispanic White patients, while 8 were reported in Hispanic patients. The causes of death were similar among the 2 groups, with infection being the most common non-relapse cause of death (20% in non-Hispanic White patients, 38% in Hispanic patients). Other causes of non-relapse death were acute or chronic GVHD (40% in non-Hispanic White patients, 25% in Hispanic patients) and graft failure (0% in non-Hispanic White patients, 25% in Hispanic patients).

There was no significant difference between the cumulative incidence of relapse mortality and non-relapse mortality between the groups. However, the authors reported Hispanic (17.5%) patients had a higher percentage of relapse-related mortality at 5 years compared with non-Hispanic White patients (5.3%).

While previous studies “demonstrated racial disparities in MPN outcomes,” non-Hispanic White patients and Hispanic patients had “comparable relapse, non-relapse, and survival rates [in this analysis], likely due to similar access to treatment and follow-up within a single institution,” the authors wrote.

However, “larger and prospective studies are needed to further elucidate this important topic,” they concluded.

Reference

Ananth S, Shaughnessy P, Zoghi B, Gelfond J, Mesa RA. Race/ethnicity and outcomes in hematopoietic stem cell transplantation (HCT) in myeloproliferative neoplasms (MPN): a single institutional study. Abstract #e19083. Presented at the 2022 American Society of Clinical Oncology Annual Meeting; June 3-7, 2022; Chicago, IL.