Multicenter phase 3 trial of neoadjuvant mFOLFOX6 or CAPOX versus upfront surgery for locally advanced colon cancer

The role of neoadjuvant chemotherapy (NAC) in colon cancer is not clear. The multicenter phase 3 OPTICAL trial in China randomized patients with locally advanced colon cancer to neoadjuvant mFOLFOX orCAPOX (NAC group) or upfront surgery. The median follow-up was 48 months. There was no significant difference between the groups for the primary end point disease-free survival (at 3 years 82,1% of the patients in the NAC group versus 77.5% of the patients in the upfront surgery group. Compared with upfront surgery, NAC resulted in a 7% pathologic complete response rate, significantly lower rates of advanced tumor staging (pT3-4: 94% versus 77%), lymph node metastasis (pN1-2: 46% versus 31%), and potentially improved overall survival (sHR 0.44; 95% CI 0.25-0.77). The authors conclude that NAC versus upfront surgery did not result in improved DFS. However, the neoadjuvant approach was safe and resulted in substantial pathologic downstaging.