Tumor-Infiltrating Lymphocytes Predict Extranodal Extension and Prognosis in Regionally Advanced Oral Cavity Cancer

Area of Science:

• Oncology
• Immunology
• Pathology

Background:

• Oral cavity squamous cell carcinoma (OCSCC) presents aggressive behavior and poor survival rates.
• The prognostic role of tumor-infiltrating lymphocytes (TILs) in OCSCC is not well-established.
• p16-negative OCSCC often indicates a poorer prognosis.

Purpose of the Study:

• To determine the prognostic significance of TILs in patients with regionally advanced, p16-negative OCSCC.
• To investigate the association between TILs and extranodal extension (ENE) in OCSCC.
• To explore TILs as a potential biomarker for OCSCC management.

Main Methods:

• Retrospective analysis of 103 OCSCC patients treated with surgical resection.
• Quantification of TILs using the standardized International Immuno-Oncology Biomarkers Working Group method.
• Statistical evaluation of TILs' association with survival endpoints and ENE.

Main Results:

• High stromal TILs (>25%) at the invasive margin independently predicted improved overall survival, disease-specific survival, and disease-free survival.
• Patients with extranodal extension (ENE) had significantly lower TILs compared to ENE-negative patients (median 40% vs. 57.5%).
• TILs demonstrated a statistically significant association with both survival and ENE status.

Conclusions:

• TILs are a reliable and independent prognostic biomarker in regionally advanced OCSCC across all subsites.
• TILs are significantly associated with the presence or absence of extranodal extension.
• Findings support the integration of TILs into immunotherapeutic decision-making and further research into TIL-ENE interactions.