Effectiveness of Cetuximab as First-Line Therapy for Patients With Wild-Type KRAS and Unresectable Metastatic Colorectal Cancer in Real-Life Practice: Results of the EREBUS Cohort

Clin Colorectal Cancer. 2018 Jun;17(2):129-139. doi: 10.1016/j.clcc.2018.01.007. Epub 2018 Jan 31.


Introduction: Few real-life data are available on cetuximab benefit. The EREBUS cohort was performed to assess metastases resection rate, use, safety, and survival outcomes in wild-type KRAS (Kirsten rat sarcoma viral oncogene) patients with initially unresectable metastatic colorectal cancer (mCRC) treated by cetuximab in real practice.

Patients and methods: The study cohort comprised patients initiating cetuximab between January 2009 and December 2010 in 65 French centers, with initially unresectable mCRC and wild-type KRAS. Kaplan-Meier analysis estimated 24-month probability of metastases resection and progression-free survival, and 36-month overall survival (OS). Cox proportional hazards models investigated factors associated with survival outcomes.

Results: Among the 389 patients included, median age was 64 years, 67.4% were male, 77.9% had Eastern Cooperative Oncology Group performance status ≤ 1, and hepatic metastases were most frequent at baseline (n = 146 exclusively, n = 149 not exclusively, n = 94 nonliver only). Median duration of cetuximab use was 4.8 months. Metastases resection was performed in 106 patients (27.2%) (n = 60 liver exclusively, n = 33 not exclusively, n = 13 nonliver only). The 24-month probability (95% confidence interval) of metastases resection occurrence was 33.6% (28.5-39.3). Median progression-free survival was 9.2 (8.5-9.8) months for the total cohort and 13.0 (11.6-15.1) for those resected; median OS was 23.0 (20.6-26.3) months for the total cohort and was not reached after 36 months for those who were resected. The strongest factor associated with higher OS was metastases resection with complete remission (hazard ratio, 0.41; 95% confidence interval, 0.19-0.88).

Conclusion: This cohort study highlights in French real-life practice the benefit of cetuximab in first-line mCRC therapy, notably in case of metastases resection with complete remission.

Keywords: Colon or rectum neoplasm; Neoplasm metastasis; Observational studies; Specialties surgical.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antineoplastic Agents, Immunological / therapeutic use*
  • Cetuximab / therapeutic use*
  • Cohort Studies
  • Colorectal Neoplasms / drug therapy*
  • Colorectal Neoplasms / pathology*
  • Female
  • Humans
  • Kaplan-Meier Estimate
  • Liver Neoplasms / drug therapy
  • Liver Neoplasms / secondary
  • Liver Neoplasms / surgery
  • Male
  • Middle Aged
  • Neoplasm Metastasis / therapy
  • Progression-Free Survival
  • Proto-Oncogene Proteins p21(ras) / genetics
  • Treatment Outcome


  • Antineoplastic Agents, Immunological
  • KRAS protein, human
  • Proto-Oncogene Proteins p21(ras)
  • Cetuximab