Short-Course Radiotherapy Followed by Neoadjuvant Chemotherapy and Camrelizumab in Locally Advanced Rectal Cancer (UNION)

Short course radiotherapy, 5 \* 5Gy, once a day, 5Gy each time, for 5 days, continuous irradiation, three-dimensional 3D-CRT or IMRT technology is recommended camrelizumab 200 mg , D1, intravenous drip, q3w, 2 cycles before operation, postoperative adjuvant treatment, the longest medication time of camrelizumab was less than 1 year during the whole study period; Capecitabine 1000 mg / m2, twice a day, oral, 1-14 days, then rest for 7 days, q3w, 2 cycles before operation and 6 cycles after operation; Oxaliplatin 130 mg / m2, D1, intravenous infusion 2 hours, q3w, 2 cycles before operation, 6 cycles after operation