title: Clinical outcome of relapsed or refractory burkitt lymphoma and mature B-cell lymphoblastic leukemia in children and adolescents.
abstract: OBJECTIVE
  Despite the rapid improvement in survival rate from Burkitt lymphoma and mature B-cell lymphoblastic leukemia (B-ALL) in children, a small subset of patients do not respond to first-line chemotherapy or experience relapse (RL). Herein, we report the clinical characteristics and outcomes of these patients.
  
  
  METHODS
  RL or refractory Burkitt lymphoma and mature B-ALL in 125 patients diagnosed from 1990 to 2009 were retrospectively analyzed.
  
  
  RESULTS
  Nineteen patients experienced RL or progressive disease (PD). Among them, 12 patients had PD or RL less than six months after initial treatment and seven had late RL. Seven patients achieved complete response (CR), 11 had PD, and one had no more therapy. Six patients who achieved CR survived without evidence of disease and four of them underwent high-dose chemotherapy (HDC) followed by stem cell transplantation (SCT). However, 11 patients who failed to obtain CR eventually died of their disease. Five-year overall survival (OS) was 31.6±10.7%. OS of patients with late RL was superior to that of patients with early RL (57.1±18.7%, vs. 16.7±10.8%, p=0.014). Achievement of CR after reinduction had significant OS (p < 0.001). OS for patients who were transplanted was superior (p < 0.01). In multivariate analysis, achievement of CR after reinduction chemotherapy showed an association with improved OS (p=0.05).
  
  
  CONCLUSIONS
  Late RL and chemotherapy-sensitive patients have the chance to achieve continuous CR using HDC/SCT, whereas patients who are refractory to retrieval therapy have poor prognosis. Therefore, novel salvage strategy is required for improvement of survival for this small set of patients.
authors.affiliation: Department of Pediatrics, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Hyery
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Gyeongsang National University School of Medicine, Jinju, Korea ; Gyeongsang Institute of Health Sciences, Gyeongsang National University, Jinju, Korea.
authors.forename: Eun Sil
authors.initials: ES
authors.lastname: Park
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Soo Hyun
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hong Hoe
authors.initials: HH
authors.lastname: Koo
authors.affiliation: Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hyo Sun
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Chuhl Joo
authors.initials: CJ
authors.lastname: Lyu
authors.affiliation: Department of Pediatrics, Pusan National University School of Medicine, Busan, Korea.
authors.forename: So Eun
authors.initials: SE
authors.lastname: Jun
authors.affiliation: Department of Pediatrics, Pusan National University School of Medicine, Busan, Korea.
authors.forename: Young Tak
authors.initials: YT
authors.lastname: Lim
authors.affiliation: Department of Pediatrics, Chonnam National University Hwasun Hospital, Chonnam National University Medical School, Hwasun, Korea.
authors.forename: Hee Jo
authors.initials: HJ
authors.lastname: Baek
authors.affiliation: Department of Pediatrics, Chonnam National University Hwasun Hospital, Chonnam National University Medical School, Hwasun, Korea.
authors.forename: Hoon
authors.initials: H
authors.lastname: Kook
authors.affiliation: Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea ; Cancer Research Institute Seoul National University, Seoul, Korea.
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea ; Cancer Research Institute Seoul National University, Seoul, Korea.
authors.forename: Hyoung Jin
authors.initials: HJ
authors.lastname: Kang
authors.affiliation: Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea ; Cancer Research Institute Seoul National University, Seoul, Korea.
authors.forename: Kyung Duk
authors.initials: KD
authors.lastname: Park
authors.affiliation: Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea ; Cancer Research Institute Seoul National University, Seoul, Korea.
authors.forename: Hee Young
authors.initials: HY
authors.lastname: Shin
authors.affiliation: Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea ; Cancer Research Institute Seoul National University, Seoul, Korea.
authors.forename: Hyeo Seop
authors.initials: HS
authors.lastname: Ahn
keywords: Burkitt lymphoma; Children; Recurrence