Intrahepatic cholangiocarcinoma: Introducing the preoperative prediction score based on preoperative imaging

Background: Intrahepatic cholangiocarcinoma (ICC) still has a poor long-term outcome, even after complete resection. We investigated different parameters gathered in preoperative imaging and analyzed their influence on resectability, recurrence, and survival. Methods: All patients who underwent exploration due to ICC between January 2008 and June 2018 were analyzed retrospectively. Kaplan-Meier model, log-rank test and Cox regression were used. Results: Out of 184 patients, 135 (73.4%) underwent curative intended resection. Median overall survival (OS) was 22.2 months with a consecutive 1-, 3- and 5-year OS of 73%, 29%, and 17%. Median recurrence-free survival (RFS) was 9.3 months with a consecutive 1-, 3- and 5-year RFS of 36%, 15%, and 11%. Site of tumor, parenchymal localization, tumor configuration/dissemination, and estimated tumor volume had significant influence on resectability. Univariate analyses showed that site of tumor, tumor configuration/dissemination, number of nodules, and estimated tumor volume had predictive values for OS and RFS. Together with tumor size the preoperative prediction (POP) score was created showing significance for OS and RFS (all P < 0.001). In multivariate analysis, POP score (HR = 1.779; 95% CI: 1.268-2.495; P = 0.001), T stage (HR = 1.255; 95% CI: 1.040-1.514; P = 0.018) and N stage (HR = 1.334; 95% CI: 1.081-1.645; P = 0.007) were the independent predictors for OS. For RFS, POP score (HR = 1.733; 95% CI: 1.300-2.311; P < 0.001) and M stage (HR = 3.036; 95% CI: 1.376-6.697; P = 0.006) were the independent predictors. Conclusions: The POP score showed to have a highly significant influence on OS and RFS. The score is easy to assess through preoperative imaging. For patients in the high risk group at least staging laparoscopy or preoperative chemotherapy should be evaluated, because they showed equal outcome compared to the irresectable group.