Surgical considerations in post-programmed cell death-1 therapy for cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (cSCC) can present as advanced disease requiring systemic therapy. Programmed cell death-1 (PD-1) inhibitors such as cemiplimab enable significant tumor regression. We report a patient with advanced cSCC who achieved near-complete remission after cemiplimab, followed by Mohs surgery revealing unexpected frontal sinus communication. This case underscores the importance of considering underlying structural changes when operating in previously treated areas.