Long-Term Quality of Life Remains Positive for Transplant Patients, Regardless of Donor Match

Microscopic examination revealing red blood cells, white blood cells, neutrophils, eosinophils: ©AkuAku - stock.adobe.com

The risk of long-term adverse events and quality-of-life (QOL) status remains an unknown for patients who undergo allogeneic hematopoietic cell transplant (allo-HCT), especially those with nonmalignant conditions like aplastic anemia. A study conducted at the Fred Hutchinson Cancer Center sought to evaluate these outcomes.

A total of 122 aplastic anemia transplant patients were surveyed between 2015 and 2023, and researchers found that most survivors received transplants from matched related. Common late effects included sexual dysfunction, cataracts, and bone issues; however, most patients of working age were back to employment. Importantly, QOL scores were similar between patients who received matched related vs unrelated donors.

“The community hematologist-oncologist who are taking care of these patients when they were first diagnosed should feel reassured that the transplant is still a safe option for these patients, even when it is done for with a matched sibling donor or with matched unrelated donor or haploidentical donor,” said Neel Bhatt, MBBS, MPH, in an interview with Targeted Oncology^TM. Bhatt is an assistant professor of the Clinical Research Division at Fred Hutch and in the Department of Pediatrics at the University of Washington School of Medicine.

This study, presented at the 2024 Transplantation and Cellular Therapy Tandem Meetings, highlights the importance of long-term monitoring for post allo-HCT due to potential late effects. While no significant differences were found in QOL based on donor type, further research might be needed to explore the impact of different donors.

In the interview, Bhatt discussed the study, its findings, and main takeaways for community oncologists.

Targeted Oncology: What was the rationale for this study?

Bhatt: We understood that there is not a lot of information about long-term follow-up of patients who have undergone allogeneic bone marrow transplant for nonmalignant diseases, specifically aplastic anemia, [and] that most of the literature that is out there comes from patients who have undergone cancer and have been followed up for several years. We wanted to understand more [about] how the patients do in terms of their quality of life, their long-term organ function, and health issues.

What unmet needs exist in this patient population?

A lot of the patients with nonmalignant diseases come in with a lot of poor organ toxicities; that is from the underlying conditions. That can linger around even after transplant. We do not really understand whatthe impact of transplant is itself vs what is the impact of the underlying disease. And then sometimes when we do the transplant, there is something called mixed chimerism that can occur where some of the patient's own cells are existing, which can cause disease manifestations. We do not really understand how the interplay of previous organ problems, the current treatment that we have patients are receiving during transplant, and posttransplant complications, how the interplay of that will be.

What is this study evaluating?

At Fred Hutchinson Cancer Center, we have been sending out a survey annually to all the transplant recipients for many, many years, and we have the largest cohort of transplant survivors. We wanted to take advantage of this survey where we asked about their health outcomes, their quality of life, their medication use, are they back in school or work? We used that survey to understand how the long-term survivors of aplastic anemia are doing many, many years after transplant. We found that there were 122 patients who are in our cohort and who are almost 25 years of median for posttransplant follow, which is huge. We wanted to just use that data set and ask those questions.

The other thing we wanted to understand is how the patients who have been transplanted using matched sibling donors are doing compared to those treated with matched unrelated donors or haploidentical donors. Recently, the field of aplastic anemia is shifting towards the use of more upfront haploidentical or unrelated donor transplant, which was not the case in the past. We would always do an upfront match on a matched related donor or matched sibling donor, and if patients did not have a matched sibling donor, we would take them to immune suppressive therapy. However, since the field is shifting, we wanted to see if patients who have matched related donor vs unrelated or haploidentical donor, are they having similar quality of life after transplant? If we show that, that will at least make the hematologist-oncologists who are taking care of these patients are more reassured that yes, it is okay to refer those patients to transplant even if they do not have a matched related donor.

Could you summarize your findings?

We have 122 patients who met our study criteria. These are all pediatric adult patients with aplastic anemia. Our age range was anywhere between 1 to 67 years at the time of transplant, and the patients were a median of 50 years old at the time of the survey. The median time from transplant was 25 years, and the longest posttransplant follow-up was almost 50 years. It is great to see the follow-up of these patients this long. That is one of the strengths of our analysis.

We noticed that the patients overall had a good quality of life at this point posttransplant, even when compared with the general population. Also when we compare the quality-of-life between the donor types, most of the patients in our cohort had received matched related donors, about 70%, and rest of them had received unrelated or haploidentical donor. We found that the quality-of-life was equal. However, the numbers were small for the unrelated or haploidentical donor just because, in the past, we did not do those transplants. In the future, as we see this use of matched unrelated donors [and] haploidentical donors increasing, we hope to do the study again to see if these results are still the same.

Additionally, we saw that the majority of complications were cataracts, osteoporosis, osteopenia, and sexual dysfunction in the cohort. Almost 70% of the survivors were back to school or back to work full-time or part-time, so that was fantastic. It could be we might be seeing these results because these patients are so many years out from transplant. As a next step, we are trying to see if the results are different if we look at just patients who have been transplanted who are filling out this survey within 10 years of transplant vs 10 to 20 years, 20 to 30 years. We are going to do some additional analysis to find out if the results change. Also, we will be looking at pediatric vs adult recipients to make sure they have still a similar quality of life or if there are any differences as well.

What do you consider to be the main takeaways?

I think the biggest reassuring finding that we have from this analysis is that quality of life is overall good for patients who are getting transplanted for aplastic anemia several years after transplant. The community hematologist-oncologist who are taking care of these patients when they were first diagnosed should feel reassured that the transplant is still a safe option for these patients, even when it is done for with a matched sibling donor or with matched unrelated donor or haploidentical donor. There is a big push to have transplant done upfront for the patients even if they do not have a matched related donor because we now have a lot of options in terms of conditioning regimen and graft-vs-host disease [GVHD] prophylaxis, including the post use of posttransplant cyclophosphamide. With the use of this better supportive care and better conditioning and GVHD prophylaxis, we believe that the outcomes would be much better for patients with aplastic anemia if they are transplanted upfront.

We hope to follow these results in the next several years, again, to make sure that these results hold true. And, for the community oncologists, it would be important to track the long-term complications and the quality of life of the survivors as they are being followed in their practice after transplant, and make sure they are addressing the some of the concerns that the patients might be having.

REFERENCE:

Bhatt N, Onstad L, Carpenter P, et al. Self-Reported Late Effects and Quality of Life (QOL) of Long-Term Survivors of Severe Aplastic Anemia Who Have Undergone Allogeneic Hematopoietic Cell Transplant (HCT). Presented at: 2024 Transplantation and Cellular Therapy Tandem Meetings; February 21-24, 2024; San Antonio, TX. Abstract 474.