title: Outcome of pediatric acute lymphoblastic leukemia with very late relapse: a retrospective analysis by the Tokyo Children's Cancer Study Group (TCCSG).
abstract: Relapse period is strongly associated with second relapse risk in relapsed acute lymphoblastic leukemia (ALL) in children. In this context, the treatment outcome of very late relapse should be better; however, data regarding very late relapse is limited. We retrospectively analyzed the outcomes of two consecutive Tokyo Children's Cancer Study Group (TCCSG) ALL trials (1995-2004) with a focus on late relapse, which was divided into two categories: late relapse (6-24 months from the end of therapy, n = 48) and very late relapse (>24 months from the end of therapy, n = 57). Forty-three patients (29 late relapse and 14 very late relapse) received allogeneic hematopoietic stem cell transplantation (HSCT) at second remission. The event-free survival (EFS) probabilities of late relapse and very late relapse were 54.5 ± 7.3 and 64.8 ± 6.8 % at 7 years, respectively (P = 0.36), and were not significantly different. However, the second relapse incidence of late relapse (34.7 ± 7.1 %) was higher than that of very late relapse (15.5 ± 5.1 %, P = 0.03). The second relapse risk was low for very late relapse ALL, which suggests that these patients should be treated without allogeneic HSCT.
authors.affiliation: Department of Pediatrics, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan, katom-tky@umin.ac.jp.
authors.forename: Motohiro
authors.initials: M
authors.lastname: Kato
authors.forename: Atsushi
authors.initials: A
authors.lastname: Manabe
authors.forename: Akiko M
authors.initials: AM
authors.lastname: Saito
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Koh
authors.forename: Takeshi
authors.initials: T
authors.lastname: Inukai
authors.forename: Chitose
authors.initials: C
authors.lastname: Ogawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Goto
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tsuchida
authors.forename: Akira
authors.initials: A
authors.lastname: Ohara
mesh_terms: D000293:Adolescent; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007564:Japan; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology*; D012008:Recurrence; D012074:Remission Induction; D012189:Retrospective Studies; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome