Previous studies have proved that neoadjuvant radiotherapy can decrease the rate of local recurrence rather than distal metastases in advanced rectal cancer. Moreover, the local control was not responsible for survival benefit. Adjuvant chemotherapy is capable of eliminating the micrometastasis, rendering better prognosis to rectal cancer. However, the application of adjuvant chemotherapy depends largely on the evidence from colon cancer. At present, controversy remains on the clinical value of adjuvant chemotherapy in patients with rectal cancer who received neoadjuvant chemoradiotherapy. Besides that, the pathological stage followed by neoadjuvant chemoradiotherapy may have an effect on the evaluation of adjuvant chemotherapy. According to the postoperative pathological stage, the present study was designed as a non-inferiority trail for patients with pathological complete response or yp stage I to compare the long-term outcomes of observational group and those receiving 5-fluorouracil. For patients with yp stage II or III, the study aims to compare the effect of oxaliplatin combined with 5-fluorouracil and 5-fluorouracil alone.
The purpose of this study is to evaluate the efficacy of adjuvant chemotherapy in patients with clinical stage III rectal cancer who received neoadjuvant chemoradiotherapy on the basis of postoperative pathological stage.