TORCH-R2 is a prospective, multicenter, randomized, phase II clinical trial. Patients aged 18 years or older with pelvic recurrence rectal cancer without synchronous distant metastases or recent chemo- and/or radiotherapy treatment, Eastern Cooperative Oncology Group performance status of 0-1will be enrolled . Patients will be randomized to receive either hypofractionated radiotherapy (25-40Gy/5Fx irradiation or 15-30Gy/5Fx reirradiation), 18 weeks sintilimab and investigator's choice of first-line chemotherapy +/- target therapy (experimental arm), or conventional radiotherapy (50Gy/25Fx irradiation or 39Gy/30Fx bid reirradiation) and chemotherapy +/- target therapy (control arm). Patiens will be restaged and followed by multidisciplinary team (MDT) for decision: radical surgery, sustained systerm+/- local treatment of non resection.
The primary endpoint was progression-free survival. Secondary endpoints were objective response rate (ORR), complete response rate, R0 resection rate, duration of response (DOR), overall survival (OS), and safety and tolerability of the treatment.