Method
Data for this report come from the Florida Pediatric Bone Marrow Transplant and Cell Therapy Consortium (FPBCC). The objectives of FPBCC are to identify best pediatric HCT practices and improve survival of children receiving HCT in Florida. FPBCC was founded in 2018 and comprises 5 of the 6 pediatric transplant programs in the state of Florida, USA. All FPBCC participating centers signed memoranda of understanding and data use agreements and obtained institution-specific IRB approvals for this retrospective data analysis. Data from participating centers were downloaded from the enhanced data back to center, a CIBMTR platform, which has access to a limited CIBMTR dataset. Data were forwarded to the FPBCC statistical center, housed at the University of Florida (Gainesville, FL, USA), where data were combined into a single data set and analyzed. All participants signed an informed consent for CIBMTR data collection. Transplant centers report detailed data on consecutive hematopoietic cell transplantations to the statistical center of CIBMTR, and compliance with this reporting is monitored by on-site audits.
We describe demographics of pediatric HCT recipients, including gender, age, race, as reported to the CIBMTR. Ethnic origin (e.g. Hispanic) was not available in our dataset. Pre-transplant characteristics included diagnosis, status of disease at transplant, time from diagnosis to transplant, performance score, and number of pre-transplant comorbidities. Transplant characteristics consist of type of donor, stem cell source, Human Leukocyte Antigen (HLA) match, conditioning regimen, and regimen intensity. Outcomes data include length of survival, cause of death, and incidence and grade of GVHD. Myeloablative regimens were defined as those using one or more of the following: total body irradiation >500 cGy for a single dose or >800 cGy for fractionate, busulfan >7.2 mg/kg iv, melphalan >150 mg/m2, and thiotepa ≥10 mg/kg. Reduced intensity regimens were defined as those using melphalan ≤150 mg/m2, thiotepa <10 mg/kg, TBI >200 cGy and ≤500 cGy as a single dose or ≤800 cGy fractionated, busulfan ≤7.2 mg/kg. Non-myeloablative regimens used any dose of ATG, fludarabine, cyclophosphamide, or TBI≤200 cGy. (8) Fully HLA-matched unrelated BM or PB donors were matched at A, B, C, and DRB1 antigens by high resolution typing. For umbilical cord blood donors, full match was defined as 6/6 HLA-antigen match (A, B, DRB1). A related donor was considered haploidentical if ≥ 2 different antigens (A, B, C, or DRB1) were mismatched. CIBMTR gathers and reports acute GVHD grade following criteria published by Przepiorka et al. (9) Although currently CIBMTR gathers data on individual organ involvement with cGVHD based on NIH Consensus Criteria 2014; the data available through our platform contained only information on extent of cGVHD as limited or extensive based on definition by Shulman et al. (10) Limited cGVHD includes only localized skin involvement and/or liver dysfunction, while any other organ involvement is considered extensive.