Swiss Recommendations for Systemic Therapies in Locally Advanced and Metastatic Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma (cSCC) is the second most frequent type of non-melanoma skin cancer. Its incidence has been rising in recent years, with the highest rate reported in Switzerland compared to other countries in Europe. While the majority of cSCC cases are low-grade tumors with an excellent prognosis following surgical excision, a minority of cSCC lesions (approximately 5% of patients) progress to locally advanced cSCC (lacSCC) or distant metastatic disease (mcSCC), both of which have an unfavorable prognosis. Recent evidence from studies with checkpoint immunotherapy has changed the systemic treatment landscape for lacSCC and mcSCC patients. While both programmed death-1 (PD-1) receptor inhibitors cemiplimab and pembrolizumab are approved by the FDA, cemiplimab is the only approved systemic therapy for the treatment of nonresectable advanced cSCC in the EU and was recently also approved in Switzerland. Based on the latest evidence from randomized clinical trials, national consensus recommendations for the systemic treatment of advanced cSCC have been defined. For classification and optimal management of patients with lacSCC or mcSCC, an interdisciplinary tumor board discussion should be mandatory. Difficult-to-treat advanced cSCC patients should be referred to and treated by specialized centers. These Swiss recommendations provide guidance for the management of patients aged ≥18 years with lacSCC or mcSCC, specifically systemic therapy with a PD-1 inhibitor in the first-line setting. These up-to-date recommendations will also help Swiss physicians in their decision-making and address treatment variability in Swiss clinical practice. Keywords: cSCC, locally advanced, metastatic, systemic treatment, immunotherapy, cemiplimab