P-282 - Palliative chemotherapy for patients 70 and above with metastatic colorectal cancer: How Much Chemotherapy is Enough?

Date 04 July 2015
Event WorldGI 2015
Session Posters
Topics Anti-Cancer Agents & Biologic Therapy
Geriatric Oncology
Palliative Care
Colon Cancer
Rectal Cancer
Presenter D. Bosse
Citation Annals of Oncology (2015) 26 (suppl_4): 1-100. 10.1093/annonc/mdv233
Authors D. Bosse1, A. Beaudoin1, M. Vickers2, F. Lemay1
  • 1Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke/CA
  • 2Ottawa Regional Cancer Center, Ottawa/CA

Abstract

Introduction

Metastatic colorectal cancer (mCRC) commonly affects elderly patients, who remain an understudied subset of patients. We analyzed the survival impact of the first and subsequent lines of chemotherapy in non-trial, ≥70 year-old patients with mCRC.

Methods

Single Centre, retrospective analysis of mCRC patients, aged ≥70 years who were candidates to receive chemotherapy, between 2004 to 2012. Overall survival (OS) and progression-free survival (PFS) were estimated with Kaplan-Meier method. Multivariate analysis (MVA) was used to adjust for age, sex, ECOG, Charlson comorbidity index, dependency to activity of daily living, exposure to ≥1 doublet, capecitabine, or best supportive care (BSC).

Results

109 patients were identified; 29 elected for BSC and 80 received chemotherapy. Patients aged 70-74 (n = 34) and ≥75 years (n = 46) had similar OS: 19.7 [95%CI: 12.6-26.7] and 17.5 months [95%CI: 11.7-23.4], respectively (p = 0.822), despite less intensive chemotherapy in the older group. In MVA, age did not affect OS (HR 0.99 [95%CI: 0.92-1.05]), while ECOG ≥2 decreased likelihood of survival (HR 3.12 [95%CI: 1.87-5.76]) and exposure to ≥1 doublet was associated with improved survival (HR 0.33 [95%CI: 0.17-0.66]). First-line doublet trended toward improved OS compared with capecitabine (HR 0.66 [95%CI: 0.41-1.07]), while PFS was superior (HR 0.46 [95%CI: 0.26-0.84]). Exposure to the 3 cytotoxic chemotherapies was not associated with improved OS compared to one doublet (HR 0.77 [95%CI: 0.41-1.43]). Both arterial and venous thrombosis rate were 8% in patients who received bevacizumab.

Conclusion

Non-trial ≥70-year patients benefit from first-line doublet chemotherapy. However, older patients of ≥75 years fared equally well despite less intensive overall treatment course, suggesting that not all elderly patients benefit from exposure to the three backbone chemotherapies. Prospective trial exploring the role of chemotherapy intensity would help optimized treatment in elderly patients.