Allogeneic Hematopoietic Stem Cell Transplantation in Puerto Rico

Abstract

The blood and marrow transplantation program at Hospital Auxilio Mutuo (HAM) in San Juan, Puerto Rico (PR) was founded on May 2015. On February 2017, the first allogeneic hematopoietic stem cell transplant (allo-HSCT) was done. Prior to this date the only option for patients from PR in need for allo-HSCT was to travel to a center in the United States (US). However, most patients faced multiple barriers to achieve this goal, including economic status, and socio-economic support. Most patient from PR had no access to allo-HSCT and faced life-threatening disease.

Data from patients undergoing allo-HSCT from February 2017 to December 2023 was collected and retrospective analysis done. A total 119 allo-HSCT were performed. The median age for allo-HSCT was 43 years, with youngest patient having 17 years and oldest having 70 years. Sex distribution was 54% females and 46% males. Most patients were part of public health system (47%).

The most frequent diagnosis among allo-HSCT was acute myelogenous leukemia (AML, 33%) followed by acute lymphoblastic leukemia (ALL, 18%), myelodysplastic syndrome (MDS, 16%), non-Hodgkin's lymphoma (NHL, 12%), severe aplastic anemia (SAA, 11%), and Hodgkin's lymphoma (7%).

Donor source was 42% match related, 57% haploidentical and 1% match unrelated. Conditioning regimen was reduced intensity (RIC) in 54% and myeloablative (MAC) in 46% of cases. The median age for MAC was 40 years and for RIC was 46 years. Most common diseases treated with RIC were SAA (20.3%), AML (20.3%), and NHL (18.3%). Most common diseases treated with MAC were AML (47.3%), ALL (29.1%) and MDS (16.4%). Overall survival (OS) at 30-days, 100-days and 1-year post-transplant was 91%, 83% and 65% respectively for allo-HSCT. Two-year OS by type of donor was 57.4% for matched related and 59.7% for haploidentical. Incidence of acute graft-versus-host disease in 2023 was 39.2%.

Existing literature suggests that studies on allo-HSCT are often not representative of the broader patient population, with a lack of diversity in terms of racial/ethnic background. This raises concerns about the applicability of research findings to diverse populations, such as the unique demographic and socio-economic profile of PR. Since February 2017, PR have access to allo-HSCT locally with the same standards and quality medical care of centers in US. The probability to find a MUD is lower for a patient from PR because of ethnical biodiversity. For this reason, haploidentical donors became a convenient and practical option for patients from PR in need of allo-HSCT. In 2023 HAM in collaboration with TCT Oncology started reporting data of allo-HSCT and autologous-HSCT performed in PR to the Center for International Blood & Marrow Transplant Research (CIBMTR). Hispanic patients from PR are now represented in these database. This effort will help support research and improve patient outcomes. Our goal is obtaining FACT accreditation by 2025.