The survival benefit of increasing the number of active drugs for metastatic colorectal cancer: A multicenter retrospective study

Abstract

Abstract Background The development of chemotherapy and treatment strategies for metastatic colorectal cancer (mCRC) have provided patients with significant survival benefits. Currently, molecular targeting agents and late‐line treatment with regorafenib and trifluridine/tipiracil (FTD/TPI) are available. However, the impact of this increase in drug availability on overall survival (OS) in mCRC remains a clinical question. Methods We retrospectively collected data on consecutive mCRC patients who were treated at three institutions in Japan. We divided the patients into three cohorts: patients who initiated first‐line treatment from Jan 2005 to Dec 2006 (cohort A: only cytotoxic drugs available), Jan 2007 to Dec 2011 (cohort B: molecular targeting drugs available), and Jan 2012 to Sep 2016 (cohort C: late‐line treatment available). Results A total of 1409 consecutive patients were analyzed. The median survival time (MST) in cohorts A, B, and C was 18.6, 25.4, and 26.4 months, respectively. The hazard ratio (HR) for cohort B versus A was 0.81 (95% CI 0.68–0.97), for cohort C versus A was 0.74 (95% CI 0.61–0.89), and for cohort C versus B was 0.92 (0.81–1.03). The median number of administered drugs (range) was 3 (1–5) in cohort A, 4 (1–7) in cohort B, and 4 (1–7) in cohort C. The increase in drug availability extended the MST from 15.5 months in patients treated with ≤3 drugs to 36.0–37.3 months in patients treated with six to seven drugs. Conclusion The development of chemotherapy including late‐line treatments could improve the prognosis of mCRC patients.

Keywords

• colorectal cancer
• continuum of care
• drug availability
• late‐line treatment
• regorafenib
• trifluridine/tipiracil