Prospective study of sentinel node biopsy for high-risk cutaneous squamous cell carcinoma of the head and neck.

BACKGROUND Nodal metastasis from cutaneous squamous cell carcinoma (SCC) is poorly predicted clinically and is associated with a high mortality rate. METHODS From 2010 to 2013, patients with high-risk cutaneous SCC were assessed with sentinel node biopsy (SNB) either at the time of primary cutaneous tumor resection or at secondary wide local excision. RESULTS Of 57 patients, 8 (14%) had nodal metastasis. Significant predictors of metastasis are the number of high-risk factors (p = .008), perineural invasion (PNI; p = .05), and lymphovascular invasion (LVI; p = .05). During a mean of 19.4 months, 9 patients developed recurrence and 6 died of cutaneous SCC, indicating that over 1300 patients would be required for a randomized controlled trial with 80% power to detect a significant difference in disease-free survival. CONCLUSION Lymph node metastasis occurs in 14% of patients with high-risk cutaneous SCC. Larger studies will be required to identify which "high-risk" factors should be considered as an indication for surgical assessment of the nodal basin. © 2015 Wiley Periodicals, Inc. Head Neck 38: E884-E889, 2016.