Log odds of positive lymph nodes as an independent predictor of overall survival in oral squamous cell carcinoma.

CONTEXT

Log odds of positive lymph nodes (LODDS) have been recently demonstrated as a very promising staging model and have outperformed AJCC pN, lymph node ratio (LNR) category in major cancers. Literature is scarce concerning the prognostic ability of LODDS in oral squamous cell carcinoma (OSCC) patients.

AIMS

The present study was aimed to evaluate the importance of LODDS in predicting locoregional recurrence and overall survival (OS) in patients with OSCC compared to LNR.

SETTINGS AND DESIGN

The retrospective study was carried out on 194 patients with OSCC cases treated by surgery ± adjuvant therapy from 2008 to 2014 at our institution.

SUBJECTS AND METHODS

Demographical and clinicopathological details of study cases were recorded. LNR and LODDS were calculated and expressed as a percentage and mean ± standard deviation.

STATISTICAL ANALYSIS USED

The OS analysis was done by the Kaplan-Meier curve followed by log-rank (mantel-cox) test. Univariate and multivariate survival analysis was done to analyze the prognostic ability of LNR% and LODDS after adjusting the clinicopathological parameters by the Cox proportional hazards model.

RESULTS

Patients with cut off values of LODDS >-1.2 and LNR% >4 had significantly lower mean OS ( ≤ 0.001). Multivariate analysis indicated that only mean LODDS >-1.2 was significantly associated with poor OS. Although there was a correlation with locoregional recurrence, LODDS and LNR failed to be the independent predictors of locoregional recurrence.

CONCLUSIONS

LODDS was an independent reliable prognostic indicator for patients with OSCCs than conventional staging systems and LNR.