Peripheral Blood Stem Cell Collections in Childhood Tumor Patients Weighing Less than 25 kg Using Large Volume Leukapheresis

Kim, Mun Jeong; Kim, Hyun Ok; Lim, Hwan Sub; Lim, Hyun Sook; Cho, Hyun Sang; Lyu, Chuhl Joo; Kim, Kir Young

Abstract

BACKGROUND: Peripheral blood stem cell (PBSC) transplantation has been widely used to support the hematopoietic recovery after high dose chemotherapy in patients with advanced malignancies. The procedure of PBSC collection in pediatric patients is similar to that in adults, but needs the 'fine tuning' of the volume shift of each procedure and the technical factors to achieve specific target goals. This article provides our experience with fourteen collections of PBSC from five patients less than 25 kg in weight.
METHODS
Patient's diagnoses were 2 stage IV neuroblastoma, 1 non-Hodgkin's lymphoma, 1 stage IV Ewing sarcoma, and 1 stage IV rhabdoid tumor of kidney. Their age ranged from 2 to 7 years old. Collections were performed using COBE Spectra or CS3000 plus that had been primed with leukoreduced, irradiated red blood cells. Patients underwent large volume leukapheresis. Radial artery was used as draw line and subclavian vein was used as return line. The blood to ACD ratio was 24:1 with 3000 units of heparin added to each 500 mL of ACD, in addition, heparin (1000 units) was added to collection bag when performed with COBE Spectra. Simultaneously, calcium chloride solution was dripped into an another venous line. During one course of large volume leukapheresis, about 5,000 mL of blood (>three total blood volume) were processed at a flow rate of 25~35 mL/min.
RESULTS
The mean of total WBCs in collected components per procedure was 5.9+/-2.9x109 (3.0-10.5x109) with yield of 3.6+/-2.0x108 per kg of body weight. The mean of total CD34+ cells was 5.2+/-4.5x106 per kg (1.6-14.6x106/kg) for each collection. The patients tolerated well during the procedure without any apparent symptoms related to anemia or volume deficit or overload.
CONCLUSION
In children weighing less than 25 kg, peripheral blood progenitor cell collection can be safely and efficiently performed with continuous flow blood cell separators, primed with red cells and additional heparin anticoagulation.