# Optimizing Access to Unrelated Donors in Canada: Re-Examining the Importance of Donor Factors on Outcomes Following Hematopoietic Cell Transplantation

## TL;DR

This paper reviews how non-HLA donor factors can influence outcomes in hematopoietic cell transplantation and suggests their importance in donor selection.

## Contribution

The paper updates the importance of non-HLA donor factors in the context of improved immune complication management.

## Key findings

- Non-HLA donor factors like age, CMV status, and ABO matching significantly impact transplant outcomes.
- Improved management of immune complications allows for more consideration of HLA-mismatched donors.
- Domestic donor availability and usage can optimize transplant outcomes.

## Abstract

HLA-matched allogeneic hematopoietic cell transplantation (HCT) is a curative therapy for many patients. Unrelated HLA-matched donors are the most frequently used donor for HCT. When more than one donor transplant option is available, transplant centers can select donors based on non-HLA factors. With improved ability to prevent and treat immune complications, such as graft-versus-host disease and infections, it may be possible to proceed more often using HLA-mismatched donors, allowing greater consideration of non-HLA factors, such as donor age, CMV serostatus, and ABO blood group matching, which have demonstrated important impacts on transplant outcomes. Additional factors to consider are donor availability rates and the usage of domestic donors to optimize outcomes. A review of non-HLA factors and considerations on the selection of optimal unrelated donors for HCT are provided within this updated current context.