This is a Two-cohort, Exploratory Clinical Study Assessing the Activity of Benmelstobart Alone or Combined with Anlotinib Administered Prior to Surgery in Terms of Pathological Complete Response

Cohort 1: Neoadjuvant therapy (benmelstobart combined with anlotinib, 3 cycles, every 21 days is a cycle) : benmelstobart, 1200mg, iv, day1; anlotinib, 12 mg, po, qd, was taken orally for 2 consecutive weeks and stopped for 1 week. Anlotinib was stopped 1 week before surgery. Surgery was performed 4-6 weeks after the final administration of benmelstobart as assessed by the investigator. Adjuvant therapy was evaluated by the investigator 4-6 weeks after surgery. Adjuvant therapy (benmelstobart combined with anlotinib, 12 cycles, every 21 days is a cycle) : benmelstobart, 1200mg, iv, day1; anlotinib, 12 mg, po, qd, was taken orally for 2 weeks and stopped for 1 week.

Cohort 2: Neoadjuvant therapy (benmelstobart only, 3 cycles, every 21 days is a cycle) : benmelstobart, 1200mg, iv, day1. Surgery was performed 4-6 weeks after the final administration of benmelstobart as assessed by the investigator. Adjuvant therapy was evaluated by the investigator 4-6 weeks after surgery. Adjuvant therapy (benmelstobart, 12 cycles, every 21 days is a cycle) : benmelstobart, 1200mg, iv, day1.