Clinical features of methods for collecting hematopoietic stem cells in patients with malignant neoplasms weighing up to 15 kg and early age

Relevance. Autologous hematopoietic stem cell transplantation (auto-HSCT) is an integral part of the treatment of patients with high-risk malignancies. However, carrying out the mobilization and collection of hematopoietic stem cells (HSC) for patients weighing up to 15 kg is a complex task that requires a special approach and multidisciplinary interaction.The purpose of the study is to present the experience of collecting HSC in young children weighing up to 15 kg at the Research Institute of Pediatric Oncology and Hematology of the Federal State Budgetary Institution N.N. Blokhin National Medical Research Centre of Oncology, Ministry of Health of Russia.Materials and methods. The study included 30 patients weighing up to 15 kg who received treatment from January 2020 to May 2021 at the Research Institute of Pediatric Oncology and Hematology of the Federal State Budgetary Institution N.N. Blokhin National Medical Research Centre of Oncology, Ministry of Health of Russia. Median age was 30.6 (12–48) months, median body weight was 12.2 (7.8–15) kg. Apheresis in children weighing up to 15 kg was performed in the resuscitation and intensive care unit with the condition of pre-filling the cell separator circuit with a donor irradiated erythrocyte suspension to prevent hypovolemic complications. Thirty two apheresis was performed on a cell separator of the “Spectra Optia” type. To mobilize HSC, preparations of granulocyte colony-stimulating factor with the main active ingredient filgrastim were used.Results. Twenty eight HSC apheresis procedures were successful on the first attempt, 2 patients underwent repeated apheresis (a total of 32 procedures were performed). The median number of CD34+ cells obtained was 13.9 × 106/kg (0.04–92.0 × 106/kg), and the median apheresis duration was 251 (160–415) min. In 2 children during the procedure, an immediate organization of repeated venous access was required.Conclusions. Performing HSC apheresis in children weighing up to 15 kg and young children is a safe and effective technique with the participation of a multidisciplinary team. The apheresis algorithm proposed by us makes it possible to carry out a high-quality collection of CD34+ cells, sufficient for auto-HSCT.