Management of Regional Lymph Nodes in Clinically Node-Negative Cutaneous Squamous Cell Carcinoma of the Head and Neck: A Systematic Review & Meta-Analysis

Background/Objectives: Head and neck cutaneous squamous cell carcinoma (HNcSCC) has the potential to metastasize to local lymph nodes, which can significantly impact prognosis. However, the optimal management of patients with clinically node-negative (cN0) disease remains unclear. Methods: We conducted a systematic review and meta-analysis following PRISMA guidelines. PubMed, Scopus, CINAHL, and Web of Science databases were searched from inception to 7 August 2025. Two parallel searches were conducted: one to capture management strategies and outcomes of cN0 patients with HNcSCC and one to capture occult nodal metastasis rates of the same population. Results: A total of 38 studies were included. Post-excision management strategies included observation, sentinel lymph node biopsy (SLNB), elective dissection (ED), and elective nodal irradiation. The pooled rate of occult lymph node metastasis was 13.9% in 1673 HNcSCC tumors overall and 12.5% when limited to 977 high-risk tumors. Overall recurrence in the SLNB group (8.3%) was significantly lower than both the observation (16.9%, p < 0.0001) and ED (23.7%, p < 0.0001) groups. Additionally, overall mortality in the SLNB group (6.1%) was significantly lower than observation (29.9%, p < 0.0001) and ED (31.4%, p < 0.0001). Conclusions: We found that SLNB was associated with lower recurrence and mortality compared with observation and ED. While not assumed to be causative, our findings support the role of SLNB in diagnosing occult metastasis and staging disease in this population.