title: Comparison of cetuximab to bevacizumab as the first-line bio-chemotherapy for patients with metastatic colorectal cancer: superior progression-free survival is restricted to patients with measurable tumors and objective tumor response--a retrospective study.
abstract: OBJECTIVE
  We aimed to compare the treatment efficacy of cetuximab versus bevacizumab in combination with either irinotecan-based or oxaliplatin-based regimens (targeted triplet) as the first-line treatment for patients with metastatic colorectal cancer.
  
  
  METHODS
  Between April 2005 and March 2012, patients (n = 158) diagnosed with metastatic colorectal cancer after at least four courses of first-line bevacizumab-based (n = 95) or cetuximab-based triplet (n = 63) were retrospectively analyzed. The KRAS genotypes were sequenced for all patients. The Kaplan-Meier method was used for survival analysis, and Cox proportional hazards models were used for univariate and multivariate analyses.
  
  
  RESULTS
  Cetuximab-based triplet was associated with a higher objective response rate (66.0 vs. 47.2 %, p = 0.037) and a higher conversion rate to resectability (39.7 vs. 20.0 %, p = 0.007) compared to bevacizumab-based triplet. Compared with bevacizumab-based triplet, cetuximab-based triplet significantly increased progression-free survival in patients with measurable metastatic colorectal cancer who achieved objective tumor response (responders) (median 13.1 vs. 10.5 months, p = 0.023), but no significant increase was observed for overall survival. After adjustment for group differences in baseline characteristics and combined chemotherapy agents, cetuximab-based triplet remained an independent determinant of progression-free survival in responders as compared with bevacizumab-based triplet. KRAS mutation was not a prognostic factor in patients with metastatic colorectal cancer.
  
  
  CONCLUSIONS
  As compared with bevacizumab-based triplet, cetuximab-based triplet as the first-line treatment of metastatic colorectal cancer was associated with better progression-free survival in patients with measurable tumors who achieved objective tumor response to bio-chemotherapy.
authors.affiliation: Division of Hematology and Oncology, Department of Medicine, Taipei Veterans General Hospital, No. 201, Sec. 2, Shih-Pai Road, Taipei, 112, Taiwan.
authors.forename: Yuan-Hao
authors.initials: YH
authors.lastname: Yang
authors.forename: Jen-Kou
authors.initials: JK
authors.lastname: Lin
authors.forename: Wei-Shone
authors.initials: WS
authors.lastname: Chen
authors.forename: Tzu-Chen
authors.initials: TC
authors.lastname: Lin
authors.forename: Shung-Haur
authors.initials: SH
authors.lastname: Yang
authors.forename: Jeng-Kai
authors.initials: JK
authors.lastname: Jiang
authors.forename: Yuan-Tzu
authors.initials: YT
authors.lastname: Lan
authors.forename: Chun-Chi
authors.initials: CC
authors.lastname: Lin
authors.forename: Chueh-Chuan
authors.initials: CC
authors.lastname: Yen
authors.forename: Cheng-Hwai
authors.initials: CH
authors.lastname: Tzeng
authors.forename: Hao-Wei
authors.initials: HW
authors.lastname: Teng
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D000068258:Bevacizumab; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D000068818:Cetuximab; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D000077146:Irinotecan; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D011379:Prognosis; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D000068258:Bevacizumab; D000077146:Irinotecan; D000068818:Cetuximab; D002166:Camptothecin