A UK Delphi consensus study on the definition and management of advanced cutaneous squamous cell carcinoma.

BACKGROUND: Advanced cutaneous squamous cell carcinoma (acSCC) encompasses locally advanced and metastatic disease; however, no standardized definition exists. Recognition and categorization, therefore, often rely on multidisciplinary judgment, which may lead to variations in diagnosis and management between centers. This study aimed to establish United Kingdom (UK) consensus on the definition and optimal management of acSCC. METHODS: A modified Delphi methodology was followed. Ten senior clinicians formed a steering group and identified four key topics for consensus statement development surrounding the challenges of acSCC, disease definition, assessment, and optimal management. Forty-two consensus statements were developed and distributed via an online survey to UK clinicians experienced in acSCC care. Agreement was rated on a 4-point Likert scale, with consensus predefined as ≥75% agreement. RESULTS: A total of 130 responses were received from dermatologists, oncologists, surgeons, and clinical nurse specialists, among others. The consensus threshold was met for 39 of 42 statements (93%). A consensus definition, eight best-practice recommendations, and a treatment algorithm were developed. CONCLUSION: This study provides a UK-derived definition of acSCC, addressing the current lack of agreed terminology. The study outputs may help standardize disease classification, reduce practice variation, and support more consistent management of acSCC across UK services.