Neoadjuvant Cetuximab Leading to a Complete Pathologic Response in Locally Advanced Lip Squamous Cell Carcinoma.

Vermillion lip squamous cell carcinoma (SCC) is a rare cancer, currently grouped together with the cutaneous lip under the cutaneous squamous cell carcinoma (cSCC) system. Herein, we present a case of an 81-year-old male with locally advanced lower lip SCC involving the vermillion who achieved a complete pathologic response to neoadjuvant cetuximab after the failure of the programed cell death protein-1 (PD-1) inhibitor, cemiplimab. He was followed with clinical observation, with special attention to skin/mucosal surfaces. At the 24-week follow-up visit, he had no signs of recurrence and was very content with the surgical and cosmetic outcome. To our knowledge, there have been no documented cases of successful use of cetuximab as a neoadjuvant treatment for cSCC of the vermilion lip to date. This case highlights the potential role of cetuximab in this setting, where we believe clinical trials are warranted.