Identifying CT-based risk factors associated with synchronous liver metastases in colorectal cancer

The aim of this study was to determine the radiologic risk factors of colorectal cancer (CRC) with synchronous liver metastases. A total of 197 patients with CRC who had a visible tumor on contrast-enhanced abdominopelvic computed tomography and were treated between January 2012 and December 2012 were included. Longitudinal diameter, mural thickness, primary tumor attenuation, and other metastases were evaluated independently. Univariate analysis and multivariate logistic regression analysis were used to identify risk factors associated with the presence of liver metastases. Cases were divided into two groups based on the presence or absence of liver metastases (n = 56 and 141, respectively). Primary tumors with enhancement of ≥ 90 Hounsfield units (HU) were found to have a higher risk of liver metastases than those with enhancement of < 90 HU [odds ratio (OR): 2.619, p = 0.034]. The presence of pulmonary metastases was associated with a higher risk of liver metastases (OR: 14.218, p = 0.025). The presence of lymph node metastases (N2 vs. N0) and carcinoembryonic antigen (CEA) level independently predicted the presence of liver metastases (OR: 8.766, p < 0.001; OR: 1.012, p = 0.048). The identified risk factors of synchronous liver metastases in CRC were tumor mural enhancement, pulmonary metastases, lymph node metastases, and CEA level