Participants
Patients 18 years or older
diagnosed with or treated for clinical T1 or T2 cancers with N0 or N1
nodal status and M0 OPSCC from 2004 to 2013 were eligible for inclusion
in the study. Exclusion criteria
included histologic diagnosis other than squamous cell carcinoma,
advanced clinical stage disease, cases treated with palliative intent,
and cases with missing information. Patients without known HPV status
were also included in the study. Patients without HPV status were
included in this study due to the overwhelming number (78%) of patients
within the NCDB lacking HPV status.