PD1 antibody is recommended for dMMR/MSI-H metastatic colorectal cancer patients as second line. Chemoradiotherapy is standand treatment for locally advanced rectal cancer and is also recommended as an alternative choice for unresectable locally advanced colon cancer. Thus, this phase II, single arm study will investigate the efficacy and toxicity of combination strategy using PD1 antibody and chemoradiotherapy for dMMR/MSI-H locally advnaced colorectal cancer patients, which is expected to yield higher tumor regressiona with tolerable toxicity.
PD1 antibody is now recommended for dMMR/MSI-H metastatic colorectal cancer patients as second line. Chemoradiotherapy is standand treatment for locally advanced rectal cancer and is also recommended as an alternative choice for unresectable locally advanced colon cancer. Thus, this study will investigate the efficacy and toxicity of combination strategy using PD1 antibody and chemoradiotherapy for dMMR/MSI-H locally advnaced colorectal cancer patients.