The purpose of this study was to evaluate factors affecting hematologic recovery and infection in high-dose chemotherapy(HDCT) and autologous stem cell transplantation(ASCT) in patients with high-risk solid tumor.

From January 2004 to December 2005, 72 HDCTs and ASCTs were applied to children with high-risk solid tumor at Samsung Medical Center. Medical records of these 72 HDCTs and ASCTs were retrospectively analyzed.

The single most powerful predictor of neutrophil and platelet recovery was the number of transplanted CD34⁺ cells. The duration of high fever was significantly longer in young patients, in patients treated with total body irradiation and/or thiotepa, and in patients transplanted with lower CD34⁺ cell dose(<2×10⁶/kg). However, the difference in the duration of high fever according to the number of CD34⁺ cells was not clinically significant.

Findings in this study suggest that HDCT and ASCT with low CD34⁺ cell dose is clinically feasible despite delayed hematologic recovery, especially at a dose >1×10⁶/kg per transplantation. Therefore, it is important not to defer the appropriate time for HDCT for an additional collection of hematopoietic stem cells if the number of collected CD34⁺ cells is >1×10⁶/kg per transplantation.