title: Should we continue temozolomide beyond six cycles in the adjuvant treatment of glioblastoma without an evidence of clinical benefit? A cost analysis based on prescribing patterns in Spain.
abstract: OBJECTIVE
  The standard adjuvant treatment for glioblastoma is temozolomide concomitant with radiotherapy, followed by a further six cycles of temozolomide. However, due to the lack of empirical evidence and international consensus regarding the optimal duration of temozolomide treatment, it is often extended to 12 or more cycles, even in the absence of residual disease. No clinical trial has shown clear evidence of clinical benefit of this extended treatment. We have explored the economic impact of this practice in Spain.
  
  
  METHODS
  Spanish neuro-oncologists completed a questionnaire on the clinical management of glioblastomas in their centers. Based on their responses and on available clinical and demographic data, we estimated the number of patients who receive more than six cycles of temozolomide and calculated the cost of this extended treatment.
  
  
  RESULTS
  Temozolomide treatment is continued for more than six cycles by 80.5 % of neuro-oncologists: 44.4 % only if there is residual disease; 27.8 % for 12 cycles even in the absence of residual disease; and 8.3 % until progression. Thus, 292 patients annually will continue treatment beyond six cycles in spite of a lack of clear evidence of clinical benefit. Temozolomide is covered by the National Health Insurance System, and the additional economic burden to society of this extended treatment is nearly 1.5 million euros a year.
  
  
  CONCLUSIONS
  The optimal duration of adjuvant temozolomide treatment merits investigation in a clinical trial due to the economic consequences of prolonged treatment without evidence of greater patient benefit.
authors.affiliation: Medical Oncology Service, Catalan Institute of Oncology, Hospital Germans Trias i Pujol, Carretera Canyet, s/n, 08916, Badalona, Spain, cbalana@iconcologia.net.
authors.forename: C
authors.initials: C
authors.lastname: Balañá
authors.forename: M A
authors.initials: MA
authors.lastname: Vaz
authors.forename: D
authors.initials: D
authors.lastname: Lopez
authors.forename: R
authors.initials: R
authors.lastname: de la Peñas
authors.forename: J M
authors.initials: JM
authors.lastname: García-Bueno
authors.forename: M J
authors.initials: MJ
authors.lastname: Molina-Garrido
authors.forename: J M
authors.initials: JM
authors.lastname: Sepúlveda
authors.forename: J M
authors.initials: JM
authors.lastname: Cano
authors.forename: C
authors.initials: C
authors.lastname: Bugés
authors.forename: S M
authors.initials: SM
authors.lastname: Sanz
authors.forename: J L
authors.initials: JL
authors.lastname: Arranz
authors.forename: P
authors.initials: P
authors.lastname: Perez-Segura
authors.forename: A
authors.initials: A
authors.lastname: Rodriguez
authors.forename: J M
authors.initials: JM
authors.lastname: Martin
authors.forename: M
authors.initials: M
authors.lastname: Benavides
authors.forename: M
authors.initials: M
authors.lastname: Gil
mesh_terms: D018906:Antineoplastic Agents, Alkylating / Q000008:administration & dosage* / Q000191:economics; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000191:economics; D017024:Chemotherapy, Adjuvant / Q000191:economics / Q000379:methods; D003362:Cost-Benefit Analysis; D003606:Dacarbazine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000191:economics; D005909:Glioblastoma / Q000188:drug therapy* / Q000191:economics; D006801:Humans; D010818:Practice Patterns, Physicians'; D013030:Spain; D011795:Surveys and Questionnaires; D000077204:Temozolomide
chemical_list: D018906:Antineoplastic Agents, Alkylating; D003606:Dacarbazine; D000077204:Temozolomide