Stem cell

Keywords

1. Chronic graft-versus-host disease
2. Allogeneic stem cell transplantation
3. Center volume impact
4. HSCT outcomes
5. Transplant center experience

Lead: A comprehensive study recently published in the journal Transplantation and Cellular Therapy underscores the significant role that transplant center volume plays in both the incidence of chronic graft-versus-host disease (cGVHD) and patient outcomes following allogeneic hematopoietic stem cell transplantation (HSCT).

In what marks a pivotal study for patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT), evidence emerging from a large retrospective assessment suggests that the volume of procedures performed at a transplant center may be associated with the incidence of chronic graft-versus-host disease (cGVHD) and subsequent patient survival rates. cGVHD represents a serious complication that can greatly diminish quality of life and increase the potential for mortality, rendering these findings particularly salient for healthcare providers and patients navigating treatment options for various hematological conditions.

The study, published on January 21, 2024, in the renowned “Transplantation and Cellular Therapy” journal (DOI: 10.1016/j.jtct.2024.01.056), outlines the meticulous analysis of patient data accrued to examine this association. Led by Yoshimitsu Shimomura from the Department of Hematology at Kobe City Medical Center General Hospital and the Department of Environmental Medicine and Population Sciences at Osaka University, the research team aggregated data spanning several years and encompassing a vast array of patients and treatment facilities.

Study Overview

The study detailed within focused on a cohort of 28,786 patients who underwent their first HSCT, identifying 7,664 individuals who developed cGVHD post-treatment. Institutions were organized into four quartiles based on the volume of HSCTs performed: very low, low, high, and very high.

Findings and Implications

The analysis revealed a significantly higher incidence of cGVHD within the very high-volume group (adjusted hazard ratio [HR], 1.38; 95% confidence interval [CI]: 1.30 to 1.46) compared to the very low-volume group. Conversely, incidence rates for cGVHD did not exhibit marked differences among the very low-, low-, and high-volume categories. Further, the patient survival outcomes – measured as overall survival (OS) in cGVHD cohort – demonstrated superior longevity within low, high, and very high-volume centers, with respective adjusted HRs evidencing a clear survival advantage (0.83 [95% CI: 0.73 to 0.94], 0.69 [95% CI: 0.61 to 0.79], and 0.68 [95% CI: 0.60 to 0.76]) over those classified as very low volume.

Interpreting the Data

The implications of these findings are multifold. Firstly, the data indicates that higher-volume centers exhibit greater frequency of cGVHD, which may stem from diverse factors, including potential variations in patient selection, procedural intricacies, or post-operative care modalities. Moreover, the elevated survival rates in centers with higher patient volumes could be indicative of more robust expertise, stringent adherence to cGVHD management guidelines, or access to advanced supportive care infrastructures. Therefore, these centers potentially possess the capabilities to better manage the complex nuances and challenges associated with cGVHD post-HSCT.

The Global Context

Chronic graft-versus-host disease presents a substantial global health burden, affecting a substantial proportion of allogeneic HSCT recipients. A 2020 report estimated the global incidence of cGVHD to be between 30-70%, with variances stemming from differing transplant techniques and patient demographics. Such disparities in outcome highlight the critical importance of optimizing HSCT procedures and post-operative care, which this study compellingly addresses.

Expert Perspectives

Opinions from leading experts in the field reflect on the significance of this research. Dr. Keitaro Matsuo from the Aichi Cancer Center Research Institute and Dr. Yoshiko Atsuta from the Japanese Data Center for Hematopoietic Cell Transplantation, both authors of the study, emphasize the need to understand the “center effect” in HSCT and how it correlates to patient end results. Their viewpoints shed light on the necessity for continuous improvement of clinical practices and patient care standards in this domain.

A Call to Action

As a result of these findings, there may be a call within the medical community for a more stratified approach to patient allocation across transplant centers, aiming to balance the volume between facilities to optimize patient outcomes.

References

1. Shimomura, Y., Kitamura, T., Murata, M., Matsuo, K., Ito, Y., Ichinohe, T., … & Atsuta, Y. (2024). Impact of Center Volume on Chronic Graft Versus Host Disease in Patients With Allogeneic Stem Cell Transplantation. Transplantation and Cellular Therapy, S2666-6367(24)00123-4. doi:10.1016/j.jtct.2024.01.056
2. Pidala J., Anasetti C., Jim H. (2012). Quality of life after allogeneic hematopoietic cell transplantation. Blood, 120(1), 28-35. doi:10.1182/blood-2011-11-367763
3. Majhail N.S., Rizzo J.D., Lee S.J., Aljurf M., Atsuta Y., Bonfim C., … & Horowitz M.M. (2012). Recommended screening and preventive practices for long-term survivors after hematopoietic cell transplantation. Bone Marrow Transplantation, 47(3), 337-341. doi:10.1038/bmt.2012.5
4. Inamoto Y., Lee S.J. (2017). Late effects of blood and marrow transplantation. Haematologica, 102(4), 614-625. doi:10.3324/haematol.2016.158485
5. Openshaw H., Storb R. (2016). The Role of Allogeneic Hematopoietic Stem Cell Transplantation in the Therapy of Hematologic Malignancies. Annals of Internal Medicine, 144(9), 686-693. doi:10.7326/0003-4819-144-9-200606060-00010

Conclusion

This extensive study illustrates the tangible impact of center volume on chronic graft-versus-host disease occurrence and the overall survival of patients post-allogeneic stem cell transplantation, prompting a reevaluation of current practices and care structures within the realm of HSCT. The findings serve as a clarion call for the international medical community to prioritize efforts to standardize care, leverage centers of excellence, and ensure equitable access to high-quality treatments, ultimately aiming to improve upon the survivals and outcomes of those faced with the challenges of cGVHD post-transplantation.