The Prognostic Significance of Elective Level 4 Neck Dissection in Oral Tongue Cancer

Elective neck dissection (END) for oral tongue squamous cell carcinoma (OTSCC) typically involves level 4 due to potential metastases that may bypass levels 1-2. Our study challenges this notion and investigates the necessity of level 4 inclusion in END for OTSCC.

A retrospective cohort study performed in a tertiary-care university affiliated medical center and included all OTSCC patients treated with END from 2000 to 2020, with a minimum 2-year follow-up. The study compared patients with END levels 1-3 to those with levels 1-4 regarding regional recurrence, disease-specific and disease-free survival rates.

120 patients with OTSCC and clinically negative neck were included. END included levels 1-4 in 33 patients (27.5%) and levels 1-3 in the remaining 87 patients (72.5%). Out of all 33 patients who underwent END of levels 1-4, only 1 patient had level 4 metastasis (3%). There was no significant difference in the regional recurrence rate (21.8% vs. 18.2%, p = 0.66) and level 4 recurrence rate (3.5% vs. 3%, p = 0.91) between the groups. No difference regarding 5-years overall, disease-specific, and disease-free survival was demonstrated between the 1-3 END and 1-4 END groups (69.3% vs. 61.1%, Log-rank p = 0.7, 82% vs. 66.2%, Log-rank p = 0.15% and 66.4% vs. 60.7%, Log-rank p = 0.54, respectively).

Inclusion of level 4 in the elective neck dissection for OTSCC does not seem to improve regional control, disease-free and overall survival. Hence, elective neck dissection of levels 1-3 seems appropriate for most cases of OTSCC, as for other oral cavity subsites.