Level IV neck dissection in cN0 HPV-negative oropharyngeal squamous cell carcinoma: a retrospective cohort study.

Background: As opposed to observation of the neck, elective neck dissection has a survival benefit for cN0 oropharyngeal squamous cell carcinoma (OPSCC). However, there are limited date on level IV neck dissection in human papillomavirus (HPV)-negative OPSCC because most earlier studies did not stratify by P16 or HPV status. Thus, whether to exclude level IV from selective dissection (SND) of cN0 HPV-negative OPSCC remains controversial.

Methods: In this single-center retrospective cohort study, disease-free survival (DFS) was estimated as the primary endpoint for 124 cN0 HPV-negative OPSCC patients who received SND of levels I-III (Group A) and I-IV (Group B). Overall survival (OS) and disease-specific survival (DSS) were considered secondary endpoints.

Results: For the entire cohort, the 5-year DFS rates of Groups A and B were 55.0% and 60.1%, respectively. Five-year OS rates were 58.9% and 61.5%, and 5-year DSS rates were 74.0% and 64.8%, respectively. Group B did not show higher 5-year DFS, OS, or DSS than Group A.

Conclusions: This retrospective cohort study validated that in cN0 HPV-negative OPSCC, SND including level IV does not have substantial benefits regarding DFS, OS or DSS.