Fruquintinib Plus PD-1 in Refractory MSS Metastatic Colorectal Cancer

Inclusion Criteria: 1. patients with MSS/pMMR mCRC who have been received Fruquintinib combined with anti-PD-1 antibodies after progressed at least two lines of standard chemotherapy with or without targeted drugs such as bevacizumab and cetuximab at the Hunan Cancer Hospital from 1th January 2019 to 30th June 2022; 2. Eligible patients were aged 18 years or older 3. had histologically or cytologically confirmed adenocarcinoma of the colon or rectum; 4. patients who have at least one non-resectable measurable lesion to evaluate by response evaluation criteria in solid tumors (RECIST version 1.1). 5. an Eastern Cooperative Oncology Group performance status of 0-2; Exclusion Criteria: 1. Pregnancy, lactating female or possibility of becoming pregnant during the study. 2. Has not recovered from clinically relevant non-hematologic CTCAE grade ≥ 3 toxicity of previous anticancer therapy (excluding alopecia, and skin pigmentation). 3. Has symptomatic central nervous system metastases that are neurologically unstable or requiring increasing doses of steroids to control CNS disease. 4. Has severe or uncontrolled active acute or chronic infection. 5.Known carriers of HIV antibodies. 6.Confirmed uncontrolled arterial hypertension or uncontrolled or symptomatic arrhythmia.