Neoadjuvant chemotherapy with capecitabine combined with oxaliplatin for mid-low locally advanced rectal cancer with negative mesorectal fascia:Long-term outcomes of a prospective trial(PKUCH-R03 trial)

Objective:To evaluate the safety and efficacy of neoadjuvant chemotherapy(NCT)in mid-low locally advanced rectal cancer with negative mesorectal fascia(MRF).Methods:This prospective,single-arm phaseⅡtrial was designed and conducted at Peking University Cancer Hospital.The patients who provided consent received 3 months of NCT(capecitabine and oxaliplatin,CapOX)followed by total mesorectal excision(TME).The primary endpoint was the rate of pathological complete response(pCR).Results:From January 2019 through December 2021,a total of 53 patients were enrolled,7.5%of whom experienced grade 3-4 adverse events during NCT.The pCR rate was 17.0%for the entire cohort,and the overall rate of postoperative complications was 37.7%(1.9%of gradeⅢa patients).The 3-year disease-free survival rate was 91.4%,and 23.5%(12/51)of the patients suffered from major low anterior resection syndrome(LARS).Postoperative complications were independently associated with major LARS.Conclusions:For patients with mid-low rectal cancer with negative MRF,3 months of NCT were found to yield a favorable tumor response with acceptable toxicity.With fair long-term survival,the NCT regimen could be associated with low rates of perioperative complications as well as acceptable anal function.