Rachel B. Salit
SALT LAKE CITY — Hematopoietic stem cell transplant survivors who received umbilical cord blood grafts appeared less likely to experience bone loss and cardiac complications than survivors who received HLA-matched unrelated donor grafts, according to results of a single-center analysis presented at the BMT Tandem Meetings.
“We were able to corroborate prior studies that patients undergoing haploidentical and cord blood transplant are on less long-term steroids,” Rachel B. Salit, MD, assistant member of the clinical research division at Fred Hutchinson Cancer Research Center and physician at Seattle Cancer Care Alliance, told HemOnc Today. “With bigger numbers, this may be associated with decreased late effects in these groups.”
Previous research reported early outcomes of HSCT recipients based on different donor sources; however, late effects had been unknown.
Salit and colleagues sought to determine the incidence of nonmalignant late complications and quality of life among recipients of matched related, 10/10 HLA-matched unrelated, mismatched unrelated, umbilical cord blood and related haploidentical grafts.
The researchers reviewed medical records and self-reported questionnaires from 1,079 adults who received transplants between 2008 and 2016 and survived at least 1 year following transplant.
“Many patients have more than one donor option for their hematopoietic cell transplant,” Salit said. “No study has compared late effects or quality of life among transplant recipients of different donor sources. In the future, these will be important endpoints with which physicians can make decisions regarding which donor source to recommend to their patients.”
Among all patients, 357 received matched related grafts; 555 received 10/10 HLA-matched unrelated grafts; 103 received mismatched unrelated grafts; 98 received umbilical cord blood grafts and 66 received related haploidentical grafts. All groups were heterogeneous in terms of age, diagnosis, conditioning regimen, graft source and graft-versus-host disease prophylaxis.
The median age at HSCT was 52 years (range, 18-80) and survivors were followed for a median of 46 months (range, 40-49).
Researchers divided 47 nonmalignant late effects into nine categories: bone loss, psychological, cardiac, orthopedic, pulmonary, hypogonadism, systemic viral infection, respiratory virus infection and unusual infections. Researchers determined the cumulative incidence of each category at 3 years posttransplant in each donor source group and compared incidence with 10/10 HLA-matched unrelated donors.
The analysis did not include late effects that occurred between days 100 and 365.
At 3 years, significantly fewer umbilical cord blood recipients had bone loss than HLA-matched unrelated donor recipients (1.1% vs. 11%; P = .001), as well as fewer cardiac problems (0% vs. 3.9%; P = .005).
The 3-year overall chronic GVHD rate was 66%. The 3-year chronic GVHD rate appeared lowest among umbilical cord blood recipients (40%) and highest for mismatched unrelated donor recipients (82%; P < .0001).
Researchers observed no differences between groups in psychological, orthopedic, pulmonary, hypogonadism or infectious issues.
The response rate for patient-reported questionnaires was 45% over a median follow-up of 35 months. Questionnaires showed there was no difference in physical and mental functioning as measured by the 36-Item Short Form Health Survey, and no difference in self-reported Karnofsky scores between all groups.
Recipients of umbilical cord blood and haploidentical grafts appeared less likely to report taking steroids for chronic GVHD (P < .0001).
Limitations of the study included heterogeneity between groups and lack of power due to the size of the umbilical cord blood, haploidentical and mismatched unrelated donor groups compared with the matched related and HLA-matched unrelated donor groups, Salit said.
“Continued accrual and follow-up of these groups is ongoing,” Salit said. “A randomized trial is ideal but expensive, and other centers may not collect late effects/patient-reported outcomes or compare all donor sources.” – by Melinda Stevens
Salit RB, et al. Abstract 12. Presented at: BMT Tandem Meetings; Feb. 21-25, 2018; Salt Lake City.
Disclosures: HemOnc Today could not confirm the authors’ relevant financial disclosures at the time of reporting.