Minimal residual disease‐based augmented therapy in childhood acute lymphoblastic leukemia: A report from the Japanese Childhood Cancer and Leukemia Study Group

• DOI: 10.1002/pbc.22620
• Publication Date: 2010-06-09T18:29:57Z
• Authors: Kazutaka Yamaji; Tomomi Okamoto; Shohei Yokota; Arata Watanabe; Yasuo Horikoshi; Keiko Asami; Atsushi Kikuta; Nobuyuki Hyakuna; Yutaka Saikawa; Junichi Ueyama; Tsutomu Watanabe; Masahiko Okada; Takashi Taga; Hirokazu Kanegane; Kazuhiro Kogawa; Motoaki Chin; Asayuki Iwai; Takeshi Matsushita; Yasuto Shimomura; Toshinori Hori; Masahito Tsurusawa
• Keywords: Minimal Residual Disease; Risk Stratification

The majority of minimal residual disease (MRD)-positive patients with acute lymphoblastic leukemia (ALL) have poor outcomes. ALL2000 study was performed to evaluate the efficacy augmented chemotherapy based on MRD-restratification in childhood ALL.Between 2000 and 2004, 305 eligible precursor B or T-cell ALL were enrolled study. ALL941-based therapy protocol utilized PCR MRD assays using Immunoglobulin receptor gene rearrangements. They initially stratified into three risk-groups according leukocyte count age, levels measured at weeks 5 (TP1) 12 (TP2) for a second stratification. From week 14, ≥ 10(-3) received an increase (one risk group higher), while remainder continued receive initial risk-adapted therapy.The overall 5-year event-free survival (EFS) rate 79.7 ± 2.4%. stratification feasible 234 301 (77%) who achieved complete remission. EFS stratifiable (MRD) 82.5 2.6%, considerably superior 74.7 5.7% non-stratifiable (Non-MRD) (P = 0.084) 74.4 2.1% 941 0.012). MRD-positive TP2 showed inferior outcomes as compared MRD-negative cases, but difference did not reach statistically significant level any groups immunophenotypes.These results suggest that contributed better