This study evaluated the efficacy and safety of irinotecan plus raltitrexed as second-line treatment for advanced colorectal cancer patients.

An exploratory study was made among patients with advanced, previously treated colorectal cancer from June 2013 to April 2016 in the First Hospital of China Medical University. A total of 13 patients eligible were enrolled to receive irinotecan at a dose of 180 mg/m² d1, d8 plus raltitrexed at a dose of 3 mg/m² d1, every 3 weeks. All statistical analyses were performed using the SPSS (21.0) software program. Kaplan–Meier analysis and Log-rank test were used for survival analysis. P<0.05 was considered as statistically significant. The primary end point was time to progression (TTP) and objective response rate(ORR), the secondary end point was safety.

The median follow-up time was 10.1 months at data cut-off on Dec1, 2016. Eleven patients were defined progression of disease (PD) based on the criteria of RECIST 1.1, while the median TTP of second-line was 4.0 months and 6 patients died. The rate of disease control rate (DCR) was 46.2% (6 patients stable disease and 6 patients progression of disease). In univariate analysis, sex, age, body mass index (BMI), site of tumor were not associated with efficacy of chemotherapy. The main toxicities were fatigue (90%), nausea (70%), diarrhea (60%), hepatic toxicity(37.5%) and hematologic toxic (22.2%). All the toxic side effects were tolerable.

In advanced colorectal cancer patients, irinotecan plus raltitrexed as second-line treatment showed encouraging clinical activity and a tolerable safety profile. So it is expected to become an alternative chemotherapy regimen as second-line treatment of advanced colorectal cancer.