title: Duration of chemotherapy for metastatic breast cancer: a systematic review and meta-analysis of randomized clinical trials.
abstract: OBJECTIVE
  To evaluate the effect of different first-line chemotherapy durations in patients with metastatic breast cancer (MBC) on overall survival (OS) and progression-free survival (PFS).
  
  
  METHODS
  We searched literature databases to identify randomized controlled trials that compared different chemotherapy durations in the first-line treatment of MBC. Only trials with unconfounded comparisons of additional cycles of chemotherapy were included. The main outcome measures for this analysis were OS and PFS. Published data from retrieved studies were analyzed according to standard meta-analytic techniques.
  
  
  RESULTS
  We found 11 randomized clinical trials including 2,269 patients. Longer first-line chemotherapy duration resulted into a significantly improved OS (hazard ratio [HR], 0.91; 95% CI, 0.84 to 0.99; P = .046) and PFS (HR, 0.64; 95% CI, 0.55 to 0.76; P < .001). There were no differences in effects on either OS or PFS between subgroups defined by time of random assignment, study design, number of chemotherapy cycles in the control arm or concomitant endocrine therapy.
  
  
  CONCLUSIONS
  Longer first-line chemotherapy duration is associated with marginally longer OS and a substantially longer PFS.
authors.affiliation: Galliera Hospital, Genoa, Italy. alessandra.gennari@galliera.it
authors.forename: Alessandra
authors.initials: A
authors.lastname: Gennari
authors.forename: Martin
authors.initials: M
authors.lastname: Stockler
authors.forename: Matteo
authors.initials: M
authors.lastname: Puntoni
authors.forename: Mariapia
authors.initials: M
authors.lastname: Sormani
authors.forename: Oriana
authors.initials: O
authors.lastname: Nanni
authors.forename: Dino
authors.initials: D
authors.lastname: Amadori
authors.forename: Nicholas
authors.initials: N
authors.lastname: Wilcken
authors.forename: Mauro
authors.initials: M
authors.lastname: D'Amico
authors.forename: Andrea
authors.initials: A
authors.lastname: DeCensi
authors.forename: Paolo
authors.initials: P
authors.lastname: Bruzzi
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008495:Medical Oncology / Q000379:methods*; D016032:Randomized Controlled Trials as Topic; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents