Arterial hyperenhancement of small intrahepatic cholangiocarcinomas correlates with microvessel counts and patient survival

Background: To compare outcomes of patients with arterially hyperenhancing intrahepatic cholangiocarcinomas (ICC) and arterially hypoenhancing ICCs after partial hepatectomy in a cohort with an analysis of prognostic factors. Methods: From June 2009 to October 2011, a prospective cohort of 68 patients with single resectable ICCs (<= 5 cm in diameter) underwent gadolinium contrast-enhanced dynamic-phase magnetic resonance imaging and were treated with partial hepatectomy. Patients were divided into those with arterially hyperenhancing ICCs (n = 28) or arterially hypoenhancing ICCs (n = 40). Clinic-radiologic-pathologic results and survival of these patients were compared and statistically analyzed. Results: The median overall survival (OS) time was significantly longer in the arterially hyperenhancing ICCs (56.8 vs. 37.0 months) (p = 0.044). At pathologic evaluation, arterially hyperenhancing ICCs showed significantly higher microvessel count (MVC) than arterially hypoenhancing ICCs (106.2 +/- 47.5 vs. 46.9 +/- 21.6/mm(2), p = 0.001). Arterial enhancement of ICCs was found to be an independent prognostic factor for longer survival. Conclusion: The presence of arterially hyperenhancing ICCs is related to higher MVC and exhibit a better OS time than arterially hypoenhancing ICCs after partial hepatectomy.