This study aims to evaluate the clinical efficacy and safety of anlotinib in combination with penpulimab and conventional chemoradiotherapy for the neoadjuvant treatment of locally advanced rectal cancer

Penpulimab 200mg IV D1 Anlotinib 12mg P.O. QD D1-14 Radiation therapy 1.8-2Gy/50-55Gy

Chemotherapy:

Capecitabine 800mg/m2 P.O. BID D1-D14, or capecitabine plus oxaliplatin 130mg/m2. Every 21 days is 1 cycle In the above regimen, two cycles of targeted therapy (chemotherapy + immunotherapy + targeted therapy) are synchronized during radiotherapy; After the end of radiotherapy, two cycles of adjuvant chemo-immunotherapy (chemotherapy + immunotherapy) were continued.

Inclusion Criteria:

-Patient's age: 18 years old - 80 years old -

• Rectal cancer patients diagnosed with adenocarcinoma by pathological examination of primary biopsy
• Patients with no prior treatment, preoperative clinical stage: cT3-4N+M0 rectal cancer patients (AJCC 8th);
• Patients who agree to undergo radical surgical treatment and have no contraindications to surgery as judged by the surgeon;
• No other multiple primary cancers;
• At least 1 measurable or evaluable lesion according to the efficacy evaluation criteria for solid tumors version 1.1 (RECIST v1.1);
• Expected survival time≥ 3 months;
• A score of 0-1 based on the United States Eastern Cooperative Oncology Group Performance Status Score (ECOG PS score);
• The investigator plans to give PD-1 monoclonal antibody combined with chemotherapy treatment regimen after evaluation, and signs informed consent.

Exclusion Criteria:

• Active, known or suspected autoimmune disease;
• Known history of primary immunodeficiency;
• Known history of allogeneic organ transplantation and allogeneic hematopoietic stem cell transplantation;
• Pregnant or lactating female patients;
• Patients with intestinal obstruction, intestinal perforation, intestinal bleeding, etc., requiring emergency surgery;
• Uncontrolled intercurrent illness including but not limited to:
• People living with HIV (HIV antibody positive)
• Severe infections that are active or poorly clinically controlled
• Patients with active hepatitis
• Evidence of severe or uncontrolled systemic disease (e.g., severe psychiatric, neurological, epilepsy or dementia, unstable or incompensable respiratory, cardiovascular, hepatic or renal disease, uncontrolled hypertension [i.e., greater than or equal to CTCAE grade 2 hypertension despite medication]).
• Patients with active bleeding or new thrombotic disease, taking therapeutic dose of anticoagulant drugs or bleeding tendency, abnormal coagulation function (INR>1.5×ULN, APTT>1.5×ULN);
• Those who are currently undergoing clinical trials of other drugs;
• Other patients who are considered by the investigator to be unsuitable for inclusion.