Prognostic nutritional index serves as a predictive marker of survival and associates with systemic inflammatory response in metastatic intrahepatic cholangiocarcinoma

Objective: The significance of the prognostic nutritional index (PNI) has been widely reported and confirmed in many types of cancers. However, few studies are available indicating its prognostic power in patients with intrahepatic cholangiocarcinoma (ICC). Thus, we investigated its relationship with overall survival (OS) to evaluate its role in predicting survival in patients with ICC. Patients and methods: Between October 2011 and October 2015, 173 consecutive patients with pathologically confirmed locally advanced or metastatic ICC were enrolled. First, the correlations between PNI and clinical factors were analyzed among these patients. Next, univariate and multivariate analyses were conducted to evaluate the association between PNI and OS among these patients with ICC. In addition, the relationships between PNI and three typical systemic inflammatory response (SIR) markers - the neutrophil/lymphocyte ratio (NLR), the platelet/lymphocyte ratio (PLR), and the lymphocyte/monocyte ratio (LMR) - were also assessed. Results: A lower PNI was linked with a shorter OS in patients with ICC, as reflected obviously in the Kaplan-Meier analyses. The patients with ICC were divided into the locally advanced group and the metastatic group. Further analyses revealed that PNI is not associated with OS in the locally advanced group. However, in the subgroup of patients with metastatic ICC, a lower PNI significantly correlated with a worsened OS. The OS for patients with a low PNI is 5 months, whereas the OS is 10.17 months for patients with a high PNI. Multivariate analyses revealed that PNI is independently correlated with OS. We finally proved that PNI is negatively proportional to NLR and PLR and positively proportional to LMR. Conclusion: Our results demonstrate that decreased PNI signifies a poor OS and is associated with SIR in patients with metastatic ICC. Therefore, it may serve as a valuable predictive marker in patients with metastatic ICC.