Japanese Journal of Clinical Oncology 30:137-145 (2000)
© 2000 Foundation for Promotion of Cancer Research
Feasibility Study of Autologous Peripheral Blood Stem Cell Transplantation for the Treatment of Childhood Acute Myelogenous Leukemia
1Division of Hematology/Oncology, Shizuoka Children’s Hospital, Shizuoka, 2Department of Pediatrics, University of Tokushima, Tokushima, Saitama, 3Department of Pediatrics, Nakadori Hospital, Akita, 4National Defense Medical College, Tokorozawa, 5Tottori University, Tottori, 6National Children’s Hospital, Tokyo, 7Iwate Medical University, Morioka, 8Kurume University, Kurume, Fukuoka, 9National Okayama Hospital, Okayama, 10Kagoshima University, Kagoshima, 11Asahikawa Medical College, Asahikawa, Hokkaido, 12National Medical Center, Tokyo, 13Kanazawa University, Kanazawa, 14Aichi Medical University, Aichi-gun, Aichi, 15Children’s Cancer and Leukemia Study Group of Japan (CCLSG) and 16Haematopoietic Stem Cell Transplantation Unit, National Cancer Center Hospital, Tokyo, Japan
Background: The primary object of this study was to identify treatment-related variables that may predict relapse of acute myelogenous leukemia (AML) after autologous peripheral blood stem cell transplantation (PBSCT), which will be critical for the development of a suitable protocol for wider application.
Methods: A total of 28 children (age 0–18 years) with AML underwent PBSCT and have had a minimum follow-up of 25 months; including 24 patients in their first complete remission (CR) and four in their second CR. The patients were divided into two cohorts according to the study phase: 16 patients were treated in an early phase pilot study and 12 patients in their first CR were treated in a prospective trial. Fifteen of the first-CR patients had any of the cited high-risk features of high WBC count (>100 x 109/l; n = 5), FAB M0/M4/M5/M7 subtypes (n = 11) or delayed achievement of CR (n = 9). Except in one patient, cytoreductive regimens did not include total body irradiation (TBI).
Results: After PBSCT, one patient died of veno-occulsive disease (VOD) and another patient relapsed early on day 43, but the remaining patients showed engraftment. Leukemic relapse was observed 1–29 months after PBSCT (median, 8 months ); in all of the 4 children treated in their second CR and in 11 of the 24 patients (46%) treated in their first CR. The remaining patients have been disease-free for 24 to 97 months (median, 53 months ). Using a multivariate analysis, the timing of apheresis was the most significant prognostic factor for those treated in their first CR (p = 0.03); 12 of the 16 patients whose PBSC were collected beyond 2.5 months of CR continue to remain in CR, while seven of the eight patients whose PBSC were harvested within 2.5 months of CR relapsed.
Conclusion: Although the small number of patients studied does not allow firm conclusions to be drawn regarding the relative effectiveness of this therapy, the results do suggest the feasibility of further studies of PBSCT for the treatment of childhood AML with high-risk features including the assessment of minimum residual disease.
+ For reprints and all correspondence: Yoichi Takaue, Department of Medical Oncology, National Cancer Center Hospital, 1–1 Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045, Japan. E-mail: ytakaue@ncc.go.jp