Abstract 115P
Background
The standard first-line chemotherapy for metastatic colorectal cancer (mCRC) is fluoropyrimidine-based doublet chemotherapy plus molecular target agent; however, optimal chemotherapeutic standard remains unknown in the elderly aged ≥75 years. We thus conducted the present retrospective study to establish optimal first-line chemotherapy for the elderly aged ≥75 years.
Methods
One hundred seven mCRC patients aged ≥75 years who received palliative chemotherapy from 2011 to 2021 at Nagoya City University Hospital were enrolled in this retrospective study. According to the first-line chemotherapy regimen, patients were categorized into the doublet group (doublet cytotoxic drugs ± bevacizumab (BV)) and the single group (single cytotoxic drug ± BV, or anti-EGFR antibody alone). In addition, prognostic factors were analyzed in the elderly chemotherapy.
Results
In total, 107 patients were included in this study, and median age was 78 years old (range, 75-92). Median OS and PFS were 24.8 m and 8.0m, respectively. In 66 patients with 75-79 years of age, 59 patients (89.4%) received doublet cytotoxic drugs and only 7 patients were in the single group. In 41 patients aged ≥80 years, 22 patients were in the doublet group and 19 patients were in the single group. No significant differences were found for OS and PFS between 75-79 years and ≥80 years groups (mOS: 26.4m vs. 23.2m, P=0.603) (mPFS: 8.4 m vs. 7.8m, P=0.115), and between doublet and single groups (mOS: 26.4m vs. 20.0m, P=0.316) (mPFS: 9.3 m vs. 6.6m, P=0.578). Values of LDH, CRP, GNRI, PNI, NLR and SII index were prognostic factors. When categorized into good and poor prognostic population based on these factors, the doublet regimen showed additional survival benefit to the single regimen in the poor prognostic population, whereas no significant differences were noted between the two groups in the good prognostic population.
Conclusions
In 75-79 years of age, most of patients could receive standard chemotherapy and achieved comparable results to other clinical trials. The single regimen might be feasible treatment option for mCRC elderly patients with good prognostic factors.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.