Does Sentinel Lymph Node Biopsy Accurately Stage the Clinically Negative Neck in Early Oral Cavity Squamous Cell Carcinoma?

Abstract

Sentinel lymph node biopsy (SLNB) is being increasingly used worldwide as a minimally invasive option to stage the clinically node-negative neck (N0) in patients with early oral cavity squamous cell carcinomas (OCSCC). We performed this trial to assess the reliability and validity of the technique. We did this prospective interventional nonrandomized study in patients with early (cT1-T2 OCSCC) and with negative neck. All patients underwent preoperative lymphoscintigraphy; SLNB was followed immediately by completion neck dissection (CND), thus each patient serving as their own control. The primary outcomes evaluated are sentinel lymph node (SLN) detection rate, SLN retrieval rate, and SLN status (positive or negative) compared with pathology of CND specimen to detect any false negatives. The secondary outcomes included SLN analyses (tumor burden, location in different levels of the neck, laterality, extracapsular spread, and total nodes positive) and overall survival. Of 60 patients, 59 (98%) had successful SLN detection with the lymphoscintigram failing to localize in 1 patient. Of the remaining 59 patients, 58 (96%) had all the SLNs retrieved, resulting in 96.4% sentinel node retrieval rate. In total, 24 (41%) SLNs were positive with 1 false negative. Using a combination of SLN and CND findings as the gold standard for lymph node involvement status, SLNB had a sensitivity of 96% (95% confidence interval [CI]: 80-100%), a specificity of 100% (95% CI: 90-100%), and negative predictive value of 97% (95% CI: 85-100%). The results of this study suggest that SLNB is an accurate technique to assess the nodal status in patients with cT1-T2 N0 OCSCC and should be considered for eligible patients.