Sentinel lymph node biopsy in T1-T3 N0 oral tongue squamous cell carcinoma

In patients with clinically non-metastatic (N0) oral tongue squamous cell carcinoma (OTSCC), occult metastases remain a critical determinant of survival.

This study evaluates sentinel lymph node biopsy (SLNB) utilizing dual ICG fluorescent and 99mTc radioactive tracers as a less invasive technique to detect lymphatic dissemination, compared to elective neck dissection. The primary objective was to determine the sensitivity and negative predictive value of SLNB. Secondary objectives included characterizing the distribution of sentinel nodes (SNs) and metastases and to assess recurrence rates.

40 consecutive T1-T3N0 OTSCC (C02.1) patients underwent SLNB followed by ipsilateral modified neck dissection. All patients had a minimum follow-up of 24 months.

The study demonstrated a sensitivity of 92.3% (95% CI: 66.7-98.6%) and a negative predictive value of 96.4% (95% CI: 82.3-99.4%) for SLNB. In 53% of the cases, SNs were identified outside of ipsilateral levels 1-3, with 13% in the contralateral neck. Metastatic involvement of SNs outside ipsilateral levels 1-3 occurred in 42% of cases, and contralateral metastases in 8%. The overall recurrence rate was 13%, with isolated regional recurrence in 2% of patients.

The results suggest that SLNB with combined tracers is an accurate and reliable alternative to neck dissection for evaluating lymphatic spread in early-stage OTSCC.