Phase II Multicenter Study Comparing Short-Course Radiotherapy Plus PD-1 Inhibitor and FOLFOX Chemotherapy with Long-Course Chemoradiotherapy in High-Risk Locally Advanced pMMRMSS Lower Rectal Adenocarcinoma

What this Trial Is About

Researchers are studying high-risk locally advanced pMMRMSS lower rectal adenocarcinoma to compare new and conventional treatment methods. This Phase II trial evaluates the safety and effectiveness of short-course radiotherapy followed by sequential PD-1 inhibitor and FOLFOX chemotherapy against the standard long-course chemoradiotherapy. The goal is to provide strong evidence for a new treatment approach in this patient group. Participants are randomly assigned to one of two treatment groups. One group receives short-course radiotherapy followed by six cycles of FOLFOX chemotherapy combined with a PD-1 inhibitor, while the other group undergoes long-course chemoradiotherapy concurrent with six cycles of FOLFOX chemotherapy. Surgery is scheduled 2 to 4 weeks after the last chemotherapy cycle. Depending on reassessment results, participants may undergo total mesorectal excision, local excision, or a watch-and-wait approach. Post-surgery, participants receive adjuvant chemotherapy with the CAPOX regimen. Throughout the study, participants are monitored for outcomes including complete clinical response at three years and various survival rates like recurrence-free and overall survival. Researchers also assess surgery success rates and treatment-related side effects over three years. The study spans several years, with regular assessments to track treatment effects and safety. Participation lasts from treatment initiation through follow-up for three years to collect these important outcomes.

A Multicenter, Randomized Controlled Phase II Study of Short-Course Radiotherapy Followed by Sequential PD-1 Inhibitor and FOLFOX Chemotherapy Versus Long-Course Chemoradiotherapy for High-Risk Locally Advanced pMMR/MSS Lower Rectal Adenocarcinoma (STAR Trial)