title: Secondary cancers among children with acute lymphoblastic leukaemia treated by the Tokyo Children's Cancer Study Group protocols: a retrospective cohort study.
abstract: With improvement in survival, it is important to evaluate the impact of treatment on secondary cancers in acute lymphoblastic leukaemia (ALL) survivors. A retrospective cohort study comprising 2918 children diagnosed with ALL and enrolled on Tokyo Children's Cancer Study Group (TCCSG) protocols between 1984 and 2005 was conducted to evaluate the incidence of secondary cancers and associated factors including treatment protocol, cranial irradiation and other characteristics of the primary ALL. Thirty-seven patients developed secondary cancers, including acute myeloid leukaemia (n = 11), myelodysplastic syndrome (n = 5), non-Hodgkin lymphoma (n = 2), brain tumours (n = 13) and other solid carcinomas (n = 6) within a median follow-up duration of 9·5 years. The cumulative incidence of any secondary cancers was 1·0% (95% confidence interval (CI), 0·7-1·4%) at 10 years and 2·4% (95% CI, 1·5-3·7%) at 20 years, respectively. Standardized incidence rate ratio of secondary cancers was 9·3 (95% CI, 6·5-12·8). Multivariate analyses showed an increased risk of secondary cancers associated with the recent treatment protocol and cranial irradiation. There was no evidence of a reduction in secondary cancer incidence despite marked decreases in cranial irradiation use in the recent protocols.
authors.affiliation: Department of Paediatrics, St. Luke's International Hospital, Tokyo, Japan; Centre of Clinical Epidemiology, St. Luke's Life Science Institute, Tokyo, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ishida
authors.forename: Miho
authors.initials: M
authors.lastname: Maeda
authors.forename: Kevin Y
authors.initials: KY
authors.lastname: Urayama
authors.forename: Chikako
authors.initials: C
authors.lastname: Kiyotani
authors.forename: Yuki
authors.initials: Y
authors.lastname: Aoki
authors.forename: Yoko
authors.initials: Y
authors.lastname: Kato
authors.forename: Shoko
authors.initials: S
authors.lastname: Goto
authors.forename: Sachi
authors.initials: S
authors.lastname: Sakaguchi
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sugita
authors.forename: Mika
authors.initials: M
authors.lastname: Tokuyama
authors.forename: Naoya
authors.initials: N
authors.lastname: Nakadate
authors.forename: Eizaburo
authors.initials: E
authors.lastname: Ishii
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; D059248:Chemoradiotherapy; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D016609:Neoplasms, Second Primary / Q000453:epidemiology* / Q000209:etiology; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy / Q000453:epidemiology* / Q000473:pathology / Q000532:radiotherapy; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D014041:Tokyo / Q000453:epidemiology
keywords: acute lymphoblastic leukaemia; children; cumulative incidence; secondary cancers; standardized incidence rate ratio