Phase II Study of Short-Course Radiotherapy Combined With CAPEOX Chemotherapy and Serplulimab for Microsatellite Stable Rectal Cancer With Limited Synchronous Metastases

What this Trial Is About

Colorectal cancer is a common and deadly disease, with many patients diagnosed when cancer has spread to other sites, especially the liver. This study focuses on patients with a limited number of metastatic lesions in rectal cancer who are microsatellite stable or have proficient mismatch repair. Researchers aim to evaluate a new treatment approach combining immunotherapy-based total neoadjuvant therapy iTNT with short-course radiotherapy SCRT to improve outcomes in this challenging group. Participants in this trial will receive an experimental treatment involving short-course radiotherapy followed by four cycles of CAPEOX chemotherapy combined with Serplulimab as neoadjuvant therapy. After this, patients will undergo surgery to remove the primary tumor and receive local treatment for metastases. Following surgery, they will receive an additional four cycles of CAPEOX chemotherapy plus Serplulimab as adjuvant therapy. This treatment sequence is designed to enhance complete response rates and reduce recurrence risks. Throughout the study, patients will be monitored for progression-free survival over three years as the primary outcome. Secondary outcomes include the rate of no evidence of disease within three months after surgery, pathological complete response of the primary tumor, local recurrence rates over three years, and overall survival over five years. Participants will undergo imaging evaluations, laboratory tests, and clinical assessments to track treatment effects and safety over the study period, which runs until December 2032.

SCRT-CAPEOX-Serplulimab for MSS/pMMR Rectal Cancer With Oligometastases