Prognostic value of pretreatment prognostic nutritional index and lactated dehydrogenase in locally advanced nasopharyngeal carcinoma patients.

BACKGROUND

To evaluate the prognostic value of pretreatment prognostic nutritional index (PNI), lactated dehydrogenase (LDH) and their combination (PNI-LDH) in patients with locally advanced NPC receiving induction chemotherapy (IC) followed by concurrent chemoradiotherapy (CCRT).

METHODS

A total of 213 patients diagnosed with locally advanced (III-IVA) NPC between January 2013 and December 2017 were retrospectively reviewed. The optimal PNI and LDH cutoff values were determined by the quartiles. The association between PNI and LDH and the clinicopathological characteristics of the patients was examined. Survival curves were analyzed using the Kaplan-Meier method and compared by the log-rank test between the different PNI and LDH subgroups. Univariate and multivariate analyses were performed by the Cox proportional hazards regression model to evaluate the prognostic impact on overall survival (OS), progression-free survival (PFS), locoregional recurrence free survival (LRFS) and distant metastasis-free survival (DMFS). Furthermore, the prognostic values of the PNI, LDH, and PNI-LDH were evaluated by comparing the AUC area.

RESULTS

The optimal cut-off values of PNI and LDH were 52 and 177, respectively. Multivariate analyses revealed that patients with a higher PNI had inferior OS (P=0.027), PFS (P=0.040), LRFS (P=0.015) and DMFS (P=0.040), and patients with a higher LDH level had poorer OS (P=0.040), PFS (P=0.001), LRFS (P=0.001) and DMFS (P=0.001). Furthermore, EBV DNA positive, stage IVA were independent prognostic factors for survival outcomes in the multivariate analyses. Moreover, we further demonstrated that low PNI-high LDH in locally advanced NPC patients was significantly related to poor OS (P=0.012), PFS (P=0.001), LRFS (P=0.001) and DMFS (P=0.001). The AUC of the PNI, LDH and PNI-LDH were 0.653 (P=0.021), 0.647 (P=0.028) and 0.751 (P=0.001), respectively, indicating that PNI-LDH is superior to either score alone.

CONCLUSIONS

Pretreatment PNI and LDH could be considered as valuable predictors for survival outcomes in locally advanced NPC patients. The combination of them, superior to either score alone, can be used as a supplement to the traditional TNM staging system.