Impact of Treatment Prior to Allogeneic Transplantation of Hematopoietic Stem Cells in Patients with Myelodysplastic Syndrome: Results of the Latin American Bone Marrow Transplant Registry.

It has been suggested that bridging therapy with intensive chemotherapy and/or hypomethylating agents followed by hematopoietic stem cell transplantation (HSCT) can be valuable in the treatment of patients with myelodysplastic syndromes (MDS). However, the influence of this approach on HSCT outcomes remains poorly defined. Therefore, our objective was to investigate the influence of treatment before HSCT in patients with MDS. We retrospectively analyzed data from the Latin American registry of 258 patients from 17 Latin American centers who underwent HSCT from 1988 to 2019. Our data showed that there was pre-HSCT. We detected no significant difference regarding the impact on overall survival of treated and untreated patients before HSCT. Despite these data, the type of previous treatment among treated patients showed a significant difference in overall survival. Treatment with hypomethylating agents together with pre-HSCT chemotherapy seems to result in better survival of the studied population. These data correspond to the first results obtained through cooperative work between various centers in Latin America comparing the different approaches to patients and reflecting their reality and challenges. Therefore, the selection of pretransplant bridge therapy should be analyzed and focus given primarily to those approaches that result in better survival of patients with MDS.

Difficulties in the revaccination program of hematopoietic stem cell transplantation recipients.

Hematopoietic stem cell transplant (HSCT) recipients should be routinely revaccinated after transplantation. We evaluated the difficulties met in the revaccination program and how a prospective and tailored follow-up could help to overcome these obstacles. HSCT recipients (n=122) were prospectively followed up and categorized into Group 1 (n=72), recipients who had already started the revaccination program, and Group 2 (n=50), recipients starting their vaccines. Whenever a difficulty was reported, interventions and subsequent evaluations were performed. Reported problems were related to patient compliance, HSCT center and/or vaccination center. Problems related to patient compliance were less frequent than those related to HSCT center modifications of previous recommendations, or to errors made by the vaccination center. The main gap found was vaccination delays (81.9%). Advisory intervention was needed in 64% and 46% of Group 1 and Group 2, respectively (p=0.05), and was partially successful in around 70% of the cases. Total resolution was achieved in more than 35% in both groups. Improvements are needed in the Brazilian vaccination program for HSCT recipients to assure a complete and updated revaccination schedule. HSCT centers should assign nurses and transplant infectious disease specialist physicians to organize the revaccination schedule and to monitor the program development.