Patterns of nodal metastasis and prognosis in human papillomavirus-positive oropharyngeal squamous cell carcinoma.

BACKGROUND: The current American Joint Committee on Cancer (AJCC) staging system may not accurately reflect survival in patients with human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (SCC). The purpose of this study was to develop a system that more precisely predicts survival. METHODS: CT scans from 156 patients who underwent chemoradiation for advanced-stage oropharyngeal SCC with >2 years follow-up were reviewed. We modeled patterns of nodal metastasis associated with different survival rates. We defined HPV+ N1 as a single node <6 cm, ipsilaterally, contralaterally, or bilaterally. HPV+ N2 was defined as a single node ≥6 cm or ≥2 nodes ipsilaterally/contralaterally or ≥3 nodes bilaterally. HPV+ N3 was defined as matted nodes. RESULTS: There was no significant difference in disease-specific survival (DSS; p = .14) or overall survival (OS; p = .16) by AJCC classification. In patients grouped by HPV+ N1, HPV+ N2, and HPV+ N3 nodal classification, significant differences in DSS (100%, 92%, and 55%, respectively; p = .0001) and OS (100%, 96%, and 55%, respectively; p = .0001) were found. CONCLUSION: A staging system with reclassification of size, bilaterality, and matted nodes more accurately reflects survival differences in this cohort of patients. Review of the AJCC staging system with these criteria should be considered for HPV-positive oropharyngeal SCC.