Abstract 1887
Background
FOLFOX is the standard adjuvant chemotherapy for resected stage III colon cancer. MOSAIC trial was performed outside of Japan, and we conducted a phase II study (NORTH/HGCSG1003) to assess the efficacy and safety of FOLFOX as adjuvant chemotherapy for Japanese patients (pts) with resected stage III colon cancer (UMIN ID: 000004590). In 2017 ASCO-GI, Shichinohe, et al. reported that the 3-year disease-free survival rate (3y-DFS rate) as the primary endpoint was 75.2%. Recent analysis of pts with metastatic colorectal cancer has shown that primary tumor location correlates with different outcome. However, with regard to adjuvant chemotherapy for resected stage III colon cancer, there are few reports of treatment outcomes by primary tumor location.
Methods
This phase II study enrolled patients with resected stage III colon cancer. Patients received 12 cycles of FOLFOX4 or mFOLFOX6. We analyzed 264 patients registered in this phase II study. This study was analyzed by CTCAE v4.0 for adverse events (AEs) and Kaplan-Meier method for DFS and relapse-free survival (RFS). To compare with right-sided tumor (RT: Cecum to Transverse colon) and left-sided tumor (LT: Descending colon to Rectosigmoid colon), Fisher’s exact test was used in terms of patient characteristics, AE, and Log-rank test was used in DFS and RFS.
Results
Patients with RT and LT were 93 and 171, respectively. The patient characteristics between RT and LT were generally balanced except for pathological stage (IIIA/IIIB/IIIC; 6.4/78.5/15.1% in RT, 18.1/71.9/10.0% in LT; p = 0.019), number of harvested lymph nodes (median; 23 in RT, 16 in LT; p = 0.001), and perforation (0% in RT, 4.1% in LT; p = 0.054). There were no significant differences in AEs (≥Grade 3) and relative dose intensity between RT and LT. 3y DFS rate was 75.9% in RT and 73.8% in LT (HR 1.122, p = 0.636). 3y RFS rate was 77.6% in RT and 76.0% in LT (HR 1.193, p = 0.490).
Conclusions
There were no significant differences between RT and LT in the efficacy and safety of FOLFOX as adjuvant chemotherapy. This analysis suggested that FOLFOX might provide benefit for resected stage III patients regardless of primary tumor location.
Clinical trial identification
UMIN000004590
2011/01/15
Legal entity responsible for the study
Non-profit organization: Hokkaido Gastrointestinal Cancer Study Group
Funding
Non-profit organization: Hokkaido Gastrointestinal Cancer Study Group
Disclosure
S. Yuki: Honoraria: Taiho Pharmaceutical, Takeda Pharmaceutical, Merck Serono, Eli Lilly Japan, Chugai Pharmaceutical, Bayer Yakuhin, Bristol-Myers Squibb. Y. Komatsu: Research funding: Yakult Honsha. All other authors have declared no conflicts of interest.