Abstract

Purpose: In Japan, elderly people account for more than 20% of the total population. The incidence of elderly patients with advanced/recurrent colorectal cancer (ARCC) has also been increasing. However, the optimal regimen for elderly patients, especially those older than 75 years of age (late-stage elderly), has not been established. This study aims to examine the optimal chemotherapeutic regimens for late-stage elderly patients, and focuses on combined chemotherapy with Bevacizumab (Bmab)+dihydropyrimidine (DPD) dehydrogenase inhibitory fluoropyrimidine (DIF).

Methods: Between January 1996 and October 2014, 30 late-stage elderly chemotherapy-naïve patients with ARCC (male/female=16/14; average age, 79.1 years) were retrospectively reviewed. The treatment regimens were: Bmab+DIF (n=11) and other regimens (n=19).

Results: The MST was 979 days, the median PFS was 350 days and the RR was 23.3%. The grade ≥3 AEs with each of the regimens were as follows: Bmab+DIF, 1.9%, other regimens, 14.4%. Although no significant differences were observed in the OS or PFS between Bmab+DIF and the other regimens, the rate of transition to a 2nd-line chemotherapy after disease progression following first-line treatment was higher with Bmab+DIF (54.6% [6/11]) than with the other regimens (38.9% [7/18]); however, this difference did not reach statistical significance.

Conclusions: It is possible to prolong survival through chemotherapy in both late-stage elderly patients and younger patients with ARCC. Although the only appropriate specific regimen was not confirmed, given that it was associated with a 100% disease control rate, good feasibility and smooth transition to 2nd-line chemotherapy, Bmab+DIF was suggested to be a candidate treatment for late-stage elderly patients with ARCC.

Keywords: Elderly patient; Colorectal cancer; Bevacizumab; DIF