Previous radiotherapy increases the efficacy of cemiplimab in the treatment of locally advanced and metastatic cutaneous squamous cell carcinoma: a retrospective analysis

Background Cemiplimab, a PD-1 inhibitor approved in 2018 for patients with locally advanced or metastatic cutaneous squamous cell carcinoma (cSCC) who are ineligible for curative therapies, lacks clarity regarding the optimal patient selection despite its known efficacy. Objective This retrospective study aims to assess the real-world treatment patterns and outcomes in patients with cSCC at our institution. Methods A retrospective analysis of consecutively treated patients with cemiplimab for cSCC was conducted. Progression-Free Survival (PFS) and Overall Survival (OS) were evaluated alongside clinical-pathologic characteristics. Results 45 patients were included, of which 73.3% were male with a median age of 77 years. After 18 months of median follow-up median PFS and OS were not reached with a mean of 21.3 months ± 2.2 months and 25.3 ± 2.1 months, respectively. Univariate and multivariate analyses revealed significant correlations only between PFS and previous radiotherapy (p-values: 0.043 and 0.046, respectively).Limitations: limitations include its retrospective nature, the low number of patients analyzed and the potential for inherent biases. Conclusions The study reveals a significant association between prior radiotherapy and improved PFS in cemiplimab-treated cSCC, suggesting the potential for combining radiotherapy with cemiplimab. Further exploration of this combined approach is warranted.