title: A multi-centre Canadian pilot study of metronomic temozolomide combined with radiotherapy for newly diagnosed paediatric brainstem glioma.
abstract: OBJECTIVE
  Survival rates for paediatric diffuse intrinsic brainstem glioma (DIBSG) are dismal. Metronomic dosing of temozolomide (TMZ) combined with standard radiotherapy may improve survival by increasing the therapeutic index and anti-angiogenic effect of TMZ. This study aimed to evaluate the safety and efficacy of this regimen in paediatric DIBSG patients.
  
  
  METHODS
  Children aged 18 years or younger with newly diagnosed DIBSG were treated with standard radiotherapy and concomitant metronomic TMZ at 85 mg/m(2)/day for 6 weeks, followed by metronomic TMZ monotherapy at the same dose. Treatment was continued until tumour progression or unacceptable toxicity occurred. Primary endpoints included overall survival and toxicities. For patients who consented, plasma and urine samples were collected at diagnosis, post-induction and prior to each course of maintenance therapy for the quantification of angiogenesis markers.
  
  
  RESULTS
  Fifteen eligible patients were enrolled, with a median age of 6.4 years. The most common toxicities were myelosuppression, most notably prolonged lymphopaenia and thrombocytopaenia. The only dose-limiting toxicity was thrombocytopaenia. Intratumoural haemorrhage was confirmed in one patient. Median time to progression was 5.13 months (95% CI = 6.4, 10.8) and median overall survival (OS) was 9.8 months (95% CI = 6.4, 10.8). Six-months OS was 80% ± 10.3%, with a 1-year OS of 20% ± 10.3%. Serum levels of both VEGF and endoglin tended to decrease during the first two cycles of therapy.
  
  
  CONCLUSIONS
  Chemoradiotherapy with metronomic dosing of TMZ showed similar toxicity to previous TMZ regimens, and does not appear to improve survival in paediatric DIBSG.
authors.affiliation: Department of Paediatrics Division of Haematology/Oncology, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, Canada.
authors.forename: Julia R
authors.initials: JR
authors.lastname: Sharp
authors.forename: Eric
authors.initials: E
authors.lastname: Bouffet
authors.forename: Diana
authors.initials: D
authors.lastname: Stempak
authors.forename: Janet
authors.initials: J
authors.lastname: Gammon
authors.forename: Derek
authors.initials: D
authors.lastname: Stephens
authors.forename: Donna L
authors.initials: DL
authors.lastname: Johnston
authors.forename: David
authors.initials: D
authors.lastname: Eisenstat
authors.forename: Juliette
authors.initials: J
authors.lastname: Hukin
authors.forename: Yvan
authors.initials: Y
authors.lastname: Samson
authors.forename: Ute
authors.initials: U
authors.lastname: Bartels
authors.forename: Uri
authors.initials: U
authors.lastname: Tabori
authors.forename: Annie
authors.initials: A
authors.lastname: Huang
authors.forename: Sylvain
authors.initials: S
authors.lastname: Baruchel
mesh_terms: D000293:Adolescent; D018906:Antineoplastic Agents, Alkylating / Q000008:administration & dosage* / Q000009:adverse effects; D020295:Brain Stem Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy*; D002170:Canada; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy / Q000379:methods; D003606:Dacarbazine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D005260:Female; D005910:Glioma / Q000188:drug therapy* / Q000532:radiotherapy*; D006801:Humans; D007223:Infant; D008297:Male; D020714:Maximum Tolerated Dose; D010865:Pilot Projects; D000077204:Temozolomide; D013921:Thrombocytopenia / Q000209:etiology; D016896:Treatment Outcome
chemical_list: D018906:Antineoplastic Agents, Alkylating; D003606:Dacarbazine; D000077204:Temozolomide