Treatment and assessments
Apatinib was given as a fixed dose of 250 mg once a day, within 30 min after breakfast. Sintilimab was given within 60 min before chemotherapy by intravenous infusion of a fixed dose of 200 mg every 3 weeks. Antiemetic drugs were given by intravenous infusion 30 min before chemotherapy with either irinotecan (150 mg/m