Sentinel node biopsy in early oral squamous cell carcinomas: A 10-year experience

Objectives/Hypothesis: To evaluate the reliability of the sentinel node (SN) biopsy in early oral squamous cell carcinomas. Study Design: Prospective cohort study. Methods: We conducted a primary prospective study on 53 consecutive patients presenting T1, T2 N0 squamous cell carcinomas of the oral cavity between January 2000 and June 2003. Primary results demonstrated a negative predictive value of 100%. The series was then extended until June 2010, with a total number of 166 successful procedures. Results: The cohort accounted for 118 males and 48 females with a mean age of 56 years. The median follow-up period was 36 months. There were 42 patients (25%) with positive SNs, 14 of them (33%) only harboring micrometastasis. The negative predictive value of the sentinel node biopsy was 95.2%. The SN involvement was strongly correlated with the tumor location (34% of SN+ for the tongue vs. 13% for the floor of mouth, P =.003), tumor stage (18% of SN+ for T1 vs. 40% for T2, P =.002), depth of invasion (median depth for SN+ lesions was 6.5 mm vs. 4 mm for SN- lesions, P =.028), and lymphovascular involvement (P =.002). The false-negative rate of frozen section examination was 42%. Conclusions: The sentinel node biopsy appears to be an excellent staging method in early oral cancers. This study also provides evidence that routinely undiagnosed micrometastasis may have clinical significance.