Objective:

To analyze predictors of nodal involvement at primary surgery and characterize local and regional recurrence patterns in patients with oral squamous cell carcinoma (OSCC) of the tongue and floor of mouth.

Approach:

• Study Design: A retrospective cohort study including patients treated for primary OSCC at the institution between 2011 and 2021.
• Patient Identification: Patients were identified through diagnosis codes and verified using electronic medical records.
• Cohort Analysis: Two-stage analysis: Stage 1 for baseline characteristics and treatment patterns; Stage 2 for recurrence analyses with specific follow-up criteria.
• Endpoints: Overall oncologic recurrence, lymph node recurrence (ipsilateral and contralateral), and time-to-event calculations.

Key Findings:

• Regional nodal recurrences in OSCC predominantly occur on the ipsilateral side, particularly involving level II lymph nodes.
• Contralateral nodal recurrence is less common but noted in advanced lesions or those near the midline.
• Nodal parameters like lymph node ratio (LNR) and extranodal extension are associated with recurrence risk.

Interpretation:

Pathological findings at primary surgery may predict distinct patterns of failure, suggesting local, ipsilateral, and contralateral recurrences may be driven by different clinicopathological factors.

Limitations:

• Retrospective design may introduce biases.
• Some variables were not available for all patients due to evolving documentation standards.

Conclusion:

The study aims to enhance understanding of recurrence patterns in OSCC.