OPTN/SRTR 2021 Annual Data Report: Vascularized Composite Allograft.

Year 2020 marked the first OPTN/SRTR Annual Data Report that included a chapter on vascularized composite allograft (VCA), which encompassed reviews of data collected between 2014 (when VCA was included in the Final Rule) and 2020. The present Annual Data Report shows that the number of VCA recipients in the United States continues to be small and trended downward in 2021. While data continue to be limited by sample size, trends continue to show a predominance in White, young/middle-aged, male recipients. Similar to the 2020 report, eight uterus and one non-uterus VCA graft failures were reported from 2014 through 2021. Critical to advancement of VCA transplantation will be the standardization of definitions, protocols, and outcome measures for the different VCA types. Like intestinal transplants, it is likely that VCA transplants will be concentrated and performed at referral transplant centers.

Impact of removing OPTN region from vascularized composite allograft allocation.

On 6/18/2020, the Organ Procurement and Transplantation Network (OPTN) implemented new policy replacing OPTN region with a 500 nautical mile (NM) circle around the donor hospital for the purpose of vascularized composite allograft (VCA) allocation. We used OPTN data to assess deceased donor VCA transplants in the 3 years pre- (6/19/2017-6/17/2020) vs. post-implementation (6/18/2020-6/17/2023). A total of 19 deceased donor VCA transplants were performed pre-policy (10 uterus, 3 bilateral upper limb, 1 unilateral upper limb, 3 face, 1 abdominal wall and 1 penis), and 11 post-policy (4 uterus, 1 bilateral upper limb, 2 face, 1 trachea, 2 abdominal wall, and 1 bilateral upper limb and face). Median distance from donor hospital to transplant hospital increased from 70 NM (range: 0-524 NM) pre-policy to 119 NM (range: 0-464 NM) post-policy. The majority of transplants in both policy eras were within 500 NM of the donor hospital [89.5% (N = 17/19) vs. 100% (N = 11/11)] and most remained within the same OPTN region as the donor hospital [68.4% (N = 13/19) vs. 90.9% (N = 10/11)]. Although it is difficult to draw strong conclusions about the policy's impact due to the low transplant volume and timing of implementation relative to the COVID-19 pandemic, data in the 3 years post-implementation suggest that 500 NM circles were a reasonable replacement for OPTN region in VCA allocation. The OPTN will continue to review data to monitor the policy's impact and inform future changes to VCA allocation, such as the transition to continuous distribution, a points-based framework expected to replace the current framework.