A predictive model for patients with local-regionally advanced oropharyngeal squamous cell carcinoma treated after cervical lymph node dissection.

Purpose: To develop a nomogram to predict the cancer-specific survival of patients with local-regionally advanced oropharyngeal squamous cell carcinoma after cervical lymph node dissection.

Methods: The clinical variables of patients confirmed as having oropharyngeal squamous cell carcinoma between 2008 and 2015 were retrieved from the Surveillance, Epidemiology and End Results database. Univariate and multivariate analysis were performed, followed by the construction of nomograms for CSS. Nomogram' accuracy was evaluated through the concordance index, calibration curves and decision curve analysis.

Results: A total of 1994 oropharyngeal squamous cell carcinoma patients who underwent surgery were included in this study. Sex, T-stage, American Joint Committee on Cancer-stage, positive lymph nodes, positive lymph node ratio, log odds of positive lymph nodes, and postoperative radiotherapy were selected to establish the nomogram for oropharyngeal squamous cell carcinoma. The concordance index of the nomogram was 0.747 (95% CI 0.714-0.780) in the training calibration cohort and 0.735 (95% CI 0.68-0.789) in the validationcohort and the time-dependent Area under the curve (> 0.7) indicated satisfactory discriminative ability of the nomogram. The calibration plot shows that there is a good consistency between the predictions of the nomogram and the actual observations in the training and validation cohorts. In addition, decision curve analysis showed that the nomogram was clinically useful and had a better ability to recognize patients at high risk than the American Joint Committee on Cancer tumor-node-metastasis staging.

Conclusion: The predictive model has the potential to provide valuable guidance to clinicians in the treatment of patients with locoregionally advanced OPSCC confined to the cervical lymph nodes.