PD-0003 - Real-life use of cetuximab in 1st-line treatment of unresectable metastatic colorectal cancer (mCRC) and outcomes after surgical resection of metast...

Date 27 June 2014
Event World GI 2014
Session Poster discussion session 1 – EGFR-targeted agents
Topics Anti-Cancer Agents & Biologic Therapy
Colon Cancer
Rectal Cancer
Surgery and/or Radiotherapy of Cancer
Presenter Denis Smith
Citation Annals of Oncology (2014) 25 (suppl_2): ii5-ii13. 10.1093/annonc/mdu164
Authors E. François1, A. Fourrier-Reglat2, A. Sa-cunha2
  • 1Centre Antoine Lacassagne, Nice/FR
  • 2Université de Bordeaux, Bordeaux/FR

Abstract

Introduction

Cetuximab has demonstrated improved survival outcomes in mCRC. Surgical resection of metastases has become an option in the multidisciplinary management of initially unresectable mCRC, but few data are available concerning its benefit in real-life practice.

Methods

EREBUS is a French multicentre (n = 65) cohort that included patients with unresectable mCRC and wild-type KRAS, initiating 1st-line cetuximab between 2009 and 2010. Patients were followed 24 months and vital status was also collected at 36 months. An expert committee validated baseline resectability and resection results. Resection rates were described according to initial metastatic site(s): liver-only, liver-not exclusively, other. Multivariate cox analyses, adjusted on prognostic factors, evaluated the risk of death and progression according to whether or not patients had undergone surgery.

Results

389 patients were included: 37.5% liver-only metastases, 38.3% liver-not exclusively, 24.2% other (mainly peritoneum). Among these, 106 patients (27.2%, 95%CI [22.8-31.7]) had metastases resection, those with liver-only metastases: 41.1% [33.1-49.1], among those with liver-not exclusively: 22.1% [15.5-28.8], and among those with other sites: 13.8% [7.6-22.5]. Baseline characteristics of the 106 patients with resection: median age 62 years, 68.9% male, 92.5% ECOG = 0-1, 64.2% primary tumour resection, 66.0% single metastatic site, and 56.6% liver only metastasis. Cetuximab was combined with chemotherapy and these regimens were irinotecan (54.7%), oxaliplatin (39.6%), or irinotecan + oxaliplatin (4.7%). Median duration of cetuximab use was 6.9 months and concomitant chemotherapy use 7.9 months. The median time from initiation of first-line to first surgery was 5.3 months; mainly one-stage operative procedures were performed (71.7%). Overall 62.3% had radical resection with R0/R1/radiofrequency (liver-only: 73.3%; liver-not exclusively: 39.4% and other: 69.2%), 9.4% missing metastases (liver-only: 8.3%; liver-not exclusively: 9.1%; other: 15.4%) and 27.4% had R2 resection (liver-only: 18.3%; liver-not exclusively: 51.5%; other: 7.7%). 49.1% had post-operative complications (22.6% infection, 13.2% thromboembolic event, 10.4% fistula, 8.5% ascites, 2.8% death). At 3 years of follow-up, 67.0% of patients with resection were alive and 75.8% of the 66 patients with a radical resection (R0/R1/radiofrequency). The median time of recurrence after surgery R0/R1/radiofrequency was 5.7 months. In multivariate Cox analysis adjusted on prognostic factors, death (HR = 0.38 [0.18-0.80]) and progression (HR = 0.57 [0.39-0.83]) were less likely for patients with radical resection (R0/R1/radiofrequency) compared to other patients (non-operated, R2 resection, with missing metastases).

Conclusion

This update supports results found in RCTs of cetuximab in terms of metastasis resection rate even though patients treated in real-life are more heterogeneous. There was a higher rate of resection among patients with liver-only metastases as compared to other more rarely studied mCRC patients. A significant benefit was observed for operated patients with radical resection.