DNA index is a strong predictive marker in intrahepatic cholangiocarcinoma: the results of a five-year prospective study.

Purpose: Predictive markers for risk stratification among patients with intrahepatic cholangiocarcinoma (IHC) are still lacking. Therefore, recent studies have focused on identifying the biological aspects of tumors that can provide more information about the tumor aggressiveness. The aim of this study was to prospectively evaluate the prognostic potential of the DNA index in patients undergoing liver resection for IHC.

Methods: In a prospective long-term follow-up study, the DNA index of 65 IHC patients undergoing liver resection was assessed by DNA image cytometry, and this parameter, as well as standard histopathological parameters, correlated with the patient survival.

Results: The mean DNA index was 1.69 ± 0.66 (range, 0.9-4.3). The univariate survival analysis showed that the DNA index (p = 0.024) and tumor stage (p = 0.017) were associated with patient survival, whereas all other standard histopathological factors had no predictive value. The multivariate analysis identified the DNA index (p = 0.050) and tumor stage (p = 0.028) as independent prognostic parameters.

Conclusions: The DNA index is an independent predictive marker for IHC after liver resection. It is superior to most standard histopathological parameters and can be assessed pre- and postoperatively. Therefore, the DNA index might represent a promising tool in the decision-making process for patients with IHC.