Prognostic nutritional index and its dynamics after curative treatment are independent prognostic factors on survival in non-metastatic nasopharyngeal carcinoma

Purpose We aimed to identify the prognostic and predictive values of post-treatment prognostic nutritional index (PNI) and PNI dynamics in nasopharyngeal cancer patients (NPC) in this study. Methods One hundred seven non-metastatic NPC patients were included. PNI was calculated by using the following formula: [10 × serum albumin value (gr/dL)] + [0.005 × total lymphocyte count (per mm3)]. ROC analysis was used for determining prognostic PNI values and univariate and multivariate statistical analyses for prognostic characterization of PNI. Results The statistically significant cut-off values for pre- and post-treatment PNI were 50.65 and 44.75, respectively. Of the pre-treatment PNI analysis, PNI ≤ 50.65 group had shorter loco-regional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS), and overall survival (OS). Furthermore, for post-treatment PNI analysis, PNI ≤ 44.75 group had shorter LRRFS and OS. In univariate analysis, only pre-treatment PNI was associated with LRRFS and DMFS, while pre- and post-treatment PNI were both associated with OS. In multivariate analysis, both PNI were independent prognostic markers for OS. In the combined analysis, pre- and post-treatment PNI, differences between the groups were statistically significant, and the PNI dynamics was an independent prognostic indicator for OS. Conclusion PNI is a useful, independent prognostic marker for non-metastatic NPC patients. It is used for either pre- or post-treatment patients. Furthermore, changes in pre-treatment PNI value after curative treatment is a significant indicator for OS.