title: Impact of TCF3 rearrangement on CNS relapse in egyptian pediatric acute lymphoblastic leukemia.
abstract: BACKGROUND
  TCF3 rearrangement mostly t(1;19) (q23;p13)/ TCF3-PBX1 gene is associated with favorable outcome in acute lymphoblastic leukemia (ALL) upon treatment with intensification protocols; however, it is associated with higher incidence of central nervous system (CNS) relapse which may affect outcome of patients.
  
  
  OBJECTIVE
  We aimed to assess TCF3 rearrangement in newly diagnosed pediatric ALL patients in relation to clinical and laboratory parameters, CNS relapse, and clinical outcome.
  
  
  METHODS
  Eighty newly diagnosed pediatric ALL patients following at Pediatric Hematology Oncology Clinic, Ain Shams University Hospitals were included in this study. Their ages ranged from 0.75 to 16 years. Seventy six (95%) patients had B-lineage ALL and four (5%) had T-lineage ALL. Data recorded included; age, sex, extramedullary manifestations, CNS, and testes infiltrations, risk stratification, response to treatment, and CBC and BM findings. TCF3 rearrangement was assessed by FISH technique using dual color break-apart probe.
  
  
  RESULTS
  TCF3 rearrangement [t(1;19) (q23;p13)] was detected in 16 (20%) out of the 80 studied patients, and it was significantly associated with splenomegaly, lymphadenopathy, CNS infiltration at presentation, high total leucocytic count, low platelet count, high-risk group, and isolated CNS relapse. These results identify a group of high-risk ALL patients with high incidence of CNS relapse and poor response to standard therapeutic regimen.
  
  
  CONCLUSIONS
  Analysis of TCF3 rearrangement [t(1;19) (q23;p13)] at diagnosis may provide a valuable target for modified and intensified CNS-directed chemotherapeutic protocol aiming to improve the patients' outcome.
authors.affiliation: 1Department of Clinical Pathology, Ain Shams University, Cairo, Egypt.
authors.forename: Hoda M
authors.initials: HM
authors.lastname: ElGendi
authors.forename: Abeer A
authors.initials: AA
authors.lastname: Abdelmaksoud
authors.forename: Doaa G
authors.initials: DG
authors.lastname: Eissa
authors.forename: Samy A
authors.initials: SA
authors.lastname: Abusikkien
mesh_terms: D000293:Adolescent; D016543:Central Nervous System Neoplasms / Q000188:drug therapy / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D002878:Chromosomes, Human, Pair 1; D002888:Chromosomes, Human, Pair 19; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D015514:Oncogene Proteins, Fusion / Q000032:analysis / Q000235:genetics*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy / Q000235:genetics*; D012008:Recurrence; D014178:Translocation, Genetic
chemical_list: D015514:Oncogene Proteins, Fusion; C543638:TCF3-PBX1 fusion protein, human
keywords: ALL; CNS relapse; TCF3 rearrangement; TCF3-PBX1; t(1;19)