Donor Lung Allocation System: Pro-, Cons and Unmet Needs

The demand for donor lungs remains a limiting factor causing extended waitlist time and pre-transplant mortality. In this review article, we reviewed efforts to improve the allocation system, and we discuss pro, cons, and current unmet needs of lung transplant allocation system. The new Composite Allocation Score (CAS) was introduced in 2023 to improve patient access to organs, travel efficiency, reduce unnecessary transplants, and reduce the reliance of geographic boundaries in lung transplantation. The CAS is a dynamic and equitable scoring system considering waitlist urgency, post-transplant survival and placement efficiency. Early data on its implementation demonstrated an increased number of transplants, and a reduction of waitlist deaths and removals. However, CAS might limit transplantation for older patients and cause an increase in travel for organ procurement. Overall, the Lung CAS is a significant step towards a more equitable and efficient lung transplant allocation system.