Distant metastases in patients with intrahepatic cholangiocarcinoma: Does location matter?

Background:

Intrahepatic cholangiocarcinoma (ICC) is an aggressive tumor entity and distant metastases (DM) are common. However, studies investigating patterns and clinical relevance of DM are rare. Therefore, aim of this study was to analyze occurrence, location, and prognostic impact of distant metastases on median overall survival (mOS).

Methods and materials:

Between 1997 – 2018, 417 patients with histopathologically-confirmed ICC were referred to our center and identified out of a dedicated clinical database. Imaging studies, surgical and histopathological reports, and follow-up visits were retrospectively evaluated with respect to hepatic tumor burden and presence of DM.

Results:

Finally, 370 patients with histopathologically confirmed ICC could be included. Of these, 186 patients showed distant metastases, either initially (n = 59) or in the course of disease (n = 127). The most common metastatic sites were lung (n = 105), peritoneum (n = 81), and bone (n = 50). After detection of lung metastases, residual mOS was 5.3 months, after peritoneal metastases 4.5 months, and after bone metastases 4.4 months (p = 0.24). At the time of first metastatic occurrence, residual OS according to intrahepatic tumor burden of < 25%, 25 – 50%, and > 50% was 6.5 months, 4.9 months, and 1.2 months respectively (p < 0.001). In multivariate hazard regression analysis, hepatic tumor burden, liver function, and subsequent treatment were significant predictors of survival.

Conclusion:

While distant metastases were associated with poor outcome, there was no significant difference between metastatic sites. However, outcome was heavily influenced by hepatic tumor burden. This supports efforts to try and achieve hepatic tumor control; besides chemotherapy interdisciplinary approaches including re-resection and intra-arterial therapy might be considerations on an individual basis.