Sentinel lymph node biopsy in early-stage oral squamous cell carcinoma: clinical outcomes and optimal lymph node removal thresholds.

BACKGROUND

Sentinel lymph node biopsy (SLNB) is an effective method for managing clinically node-negative (cN0) early-stage oral squamous cell carcinoma (OSCC). This study examines lymphatic drainage patterns and clinical outcomes in pT1/T2 OSCC patients undergoing SLNB while establishing optimal thresholds for SLN identification and lymph node removal.

METHODS

Clinicopathological data were analyzed to assess associations between SLN localization and tumor characteristics. Logistic regression identified risk factors for contralateral SLN involvement. Receiver operating characteristic curves determined optimal thresholds for SLN identification and lymph node removal. Survival analysis was conducted using Kaplan-Meier curves and log-rank tests.

RESULTS

Most SLNs were ipsilateral (83.33 %), with fewer contralateral (8.33 %) or bilateral (8.33 %) cases. The most common SLN sites were Levels 1b and 2a (70.83 %), with Level 2a being the most frequent (39.58 %). Metastases were found in 8.33 % of patients, requiring neck dissection. During follow-up, 6.25 % experienced regional recurrence. Identifying ≥2 SLNs and removing >4 lymph nodes significantly improved recurrence-free survival (p < 0.05).

CONCLUSION

SLNB effectively maps lymphatic drainage in small OSCC tumors, detecting atypical pathways and metastases. Identifying at least two SLNs and removing more than four lymph nodes improves recurrence-free survival, highlighting the importance of thorough lymph node removal to optimize patient outcomes and reduce recurrence risk.