Background: The Prognostic Nutritional Index (PNI), a marker of nutritional status and systemic inflammation, is a proven prognostic biomarker in some cancers. The predictive value of PNI in biliary tract cancer (BTC) has not been established.
Objective: The aim of this study was to determine the relationship between the PNI and outcomes of resectable BTC.
Methods: In total, 430 patients with stage I-III resectable BTC [gallbladder cancer (GBC), n = 212; cholangiocarcinoma (CHO), n = 218] who had attended Fudan University Zhongshan Hospital were enrolled. The relationship between the PNI and clinical outcomes was evaluated both in the whole cohort and in selected subgroups.
Results: Eligible patients were classified into PNI-low (PNI < 45) and PNI-high (PNI ≥ 45) groups. The PNI-low group had significantly worse overall survival (OS) in both the whole cohort (p = 0.002) and in the GBC subgroup (p = 0.001), but had similar OS as the PNI-high group in the CHO subgroup (p = 0.328). Multivariate analysis revealed that low PNI is an independent risk factor for worse survival in GBC (hazard ratio 1.623, 95% confidence interval 1.063-2.480, p = 0.026). PNI was found to predict clinical outcome in women (p < 0.001) and patients without obstructive jaundice (p = 0.017) with GBC, but was not a prognostic factor in any subgroup with CHO. The estimated area under the time-dependent receiver operating characteristic curve was significantly greater when TNM stage was combined with PNI in women with GBC.
Conclusions: PNI is an independent predictor of OS in GBC, but not in CHO. It has no prognostic value in men with GBC or patients with obstructive jaundice.