Prognostic value of log odds of positive lymph nodes in patients with resectable oral squamous cell carcinoma

Objectives: Log odds of positive lymph nodes (LODDS) was reported to be significantly associated with prognosis in several malignant tumors. However, few are the studies on the correlation between LODDS and overall survival (OS) in patients with oral squamous cell carcinoma (OSCC). Materials and methods: A retrospective study including 233 patients with OSCC during 2009 to 2013 was conducted. We probed the correlation between clinicopathological factor, LODDS, lymph node ratio (LNR), pN and OS. The potential prognostic factor and the independent factor were calculated using univariate analysis and multivariate analysis respectively. The goodness of fit and the discriminability was analyzed with Somer's D value, Nagelkerke R2 index, and Akaike information criterion (AIC). Kaplan-Meier survival curve of OS was contrasted by log-rank test in LODDS, LNR and pN, respectively. Results: According to the X-tile, the cut-off values are -1.491 and -0.763 for LODDS, 0.024 and 0.133 for LNR. LODDS, LNR and pN were significantly correlated with OS by univariate analysis (P < 0.001). Multivariate analysis demonstrated LODDS, LNR and pN as an independent prognostic factors for OS (P < 0.01). Compared with pN and LNR models, LODDS showed the strongest predictive power. LODDS was superior to LNR and pN in predicting outcomes in patients with no positive lymph nodes and inadequate neck dissection. Conclusion: LODDS would be incorporated into future N classification, which may be conducive to discern the prognosis of OSCC and make a decision of adjuvant therapy in clinical practice.