Comprehensive Criteria for CRC Liver Metastases

1. CRC: all patients included in the study had a definite diagnosis of CRC. Patients who underwent surgery had a complete postoperative pathology report. Patients with advanced stage or metastases who did not undergo surgery were diagnosed by colonoscopy biopsy. 2. Liver cirrhosis: Aspartate aminotransferase-to-platelet ratio index (APRI) and Fibrosis 4 Score (FIB-4) were used as an indirect indicator for the diagnosis of liver cirrhosis with the cut-off values of 0.5 and 1.45, respectively (13 (link), 14 (link)). APRI lower than 0.5 was generally considered to exclude liver cirrhosis, and FIB-4 lower than 1.45 was generally considered to exclude liver cirrhosis (14 (link)). 3. Definition of SLM of CRC: according to international consensus (15 (link)) and the “Guidelines for the diagnosis and comprehensive treatment of liver metastases of CRC in China (2020)” (16 (link)), synchronous liver metastasis referred to liver metastases found before or at the time of diagnosis of CRC. 4. Imaging diagnosis of SLM: at least 2 or more imaging physicians with associate high title issued the corresponding diagnostic reports. The confirmation of intraoperative liver metastases should be determined by at least 2 experienced surgeons.