title: Efficacy of capecitabine monotherapy as the first-line  treatment of metastatic HER2-negative breast cancer.
abstract: OBJECTIVE
  Capecitabine is a potent and safe agent that can be used after anthracycline and taxane treatment in patients with metastatic breast cancer (MBC). The purpose of this study was to investigate the efficacy and safety of capecitabine monotherapy as a first-line treatment in human epidermal receptor 2 (HER2)-negative patients with MBC.
  
  
  METHODS
  In this single-center trial, a total of 109 HER2-negative patients with MBC who received capecitabine monotherapy as first-line treatment between 2003 and 2014 were retrospectively analyzed. Kaplan-Meier survival analysis was carried out for progression-free survival (PFS) and for overall survival (OS). Two-sided p values of <0.05 were considered statistically significant.
  
  
  RESULTS
  Median PFS was 7.0 ± 0.67 (confidence interval (CI) 5.6-8.3) months and median OS was 30 ± 4.1 (CI 21.8- 38.1) months. First-line capecitabine treatment for HER2-negative MBC was more effective in the estrogen receptor (ER)-positive patient population compared to the ER-negative group (median PFS 9 vs 4 months (p = 0.002), median OS 33 vs 21 months (p = 0.01)). Indeed, the overall response rate in the ER-negative group was 16%, while this was calculated as 38% for ER-positive cases. While most of our patient population was treated with a higher dose (1250 mg/m2), the observed grade 3-4 toxicities were lower compared to some previously reported phase II and phase III capecitabine studies.
  
  
  CONCLUSIONS
  Capecitabine monotherapy is an effective and safe regimen for ER-positive, HER2-negative patients with MBC. Its low toxicity profile compared to other intravenous cytotoxic agents and the ease of its oral administration make this agent a preferable option for both physicians and patients.
authors.forename: Taner
authors.initials: T
authors.lastname: Babacan
authors.forename: Orhan
authors.initials: O
authors.lastname: Efe
authors.forename: Ahmet S
authors.initials: AS
authors.lastname: Hasirci
authors.forename: Fatih
authors.initials: F
authors.lastname: Demirci
authors.forename: Hakan
authors.initials: H
authors.lastname: Buyukhatipoglu
authors.forename: Ozan
authors.initials: O
authors.lastname: Balakan
authors.forename: Furkan
authors.initials: F
authors.lastname: Sarici
authors.forename: Neyran
authors.initials: N
authors.lastname: Kertmen
authors.forename: Ece
authors.initials: E
authors.lastname: Esin
authors.forename: Serkan
authors.initials: S
authors.lastname: Akin
authors.forename: Ozturk
authors.initials: O
authors.lastname: Ates
authors.forename: Sercan
authors.initials: S
authors.lastname: Aksoy
authors.forename: Ali R
authors.initials: AR
authors.lastname: Sever
authors.forename: Kadri
authors.initials: K
authors.lastname: Altundag
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000737:chemistry* / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D000069287:Capecitabine; D003841:Deoxycytidine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D018572:Disease-Free Survival; D004334:Drug Administration Schedule; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D006801:Humans; D053208:Kaplan-Meier Estimate; D008408:Mastectomy / Q000379:methods; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D018714:Radiotherapy, Adjuvant; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis*; D016896:Treatment Outcome
chemical_list: D000964:Antimetabolites, Antineoplastic; D000069287:Capecitabine; D003841:Deoxycytidine; D005472:Fluorouracil; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human