Envafolimab as Neoadjuvant Immuntherapy in Resectable Local Advanced dMMR/MSI-H Colorectal Cancer

Inclusion Criteria: 1. Willing and able to provide written informed consent. 2. Histological or cytological documentation of adenocarcinoma of the colon or rectum. 3. Tumor tissues were identified as mismatch repair-deficient (dMMR) by immunohistochemistry (IHC) method or microsatellite instability-high (MSI-H) by polymerase chain reaction (PCR). 4. Male or female subjects \> 18 years \< 70 of age. 5. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. 6. Determined CT or MRI scans (done within 14 days of registration) of the chest, abdomen and pelvis: locally advanced (cT3-4 or cN1-2 \[with the definition of a clinically positive lymph node being any node ≥ 1.0 cm\]). 7. Non complicated primary tumor (obstruction, perforation, bleeding). 8. No previous any systemic anticancer therapy for colorectal cancer disease or radiologic evaluation of tumor regression \< 20% or unacceptable toxic effects during neoadjuvant chemotherapy. 9. Adequate bone marrow, hepatic and renal function as assessed by the following laboratory requirements conducted within 7 days of starting study treatment. Exclusion Criteria: 1. Previous or concurrent cancer that is distinct in primary site or histology from colon cancer within 5 years prior to randomization. 2. Significant cardiovascular disease including unstable angina or myocardial infarction within 6 months before initiating study treatment. 3. Heart failure grade III/IV (NYHA-classification). 4. Unresolved toxicity higher than CTCAE v.4.0 Grade 1 attributed to any prior therapy/procedure. 5. Subjects with known allergy to the study drugs or to any of its excipients. 6. Current or recent (within 4 weeks prior to starting study treatment) treatment of another investigational drug or participation in another investigational study. 7. Breast- feeding or pregnant women 8. Lack of effective contraception. 9. Previously received anti-programmed death-1 (PD-1) or its ligand (PD-L1) antibody, anti-cytotoxic T lymphocyte-associated antigen 4 (cytotoxic T-lymphocyte-associated Protein 4, CTLA-4) antibody or other drug/antibody that acts on T cell costimulation or checkpoint pathways. 10. With any distant metastasis.