Exocrine pancreatic insufficiency in a patient with regionally recurrent cutaneous squamous cell carcinoma undergoing treatment with cemiplimab.

Cutaneous squamous cell carcinoma (cSCC) is a common non-melanoma skin cancer with low rates of local recurrence or distant metastasis except for tumours with high-risk features, which result in significantly decreased rates of overall survival compared with low-risk lesions. Immune checkpoint inhibitors (ICIs) (cemiplimab and pembrolizumab) represent a promising therapeutic option for cases of unresectable or metastatic disease, but despite their benefit, they pose a risk of immune-related adverse effects. We present the case of a patient with recurrent cSCC on cemiplimab, who developed exocrine pancreatic insufficiency induced by ICI. She presented with symptoms related to malabsorption that improved with pancrelipase but did not exhibit hyperglycaemia, contrary to what is commonly described with ICI-exocrine pancreatic insufficiency (EPI). This case highlights the importance of recognising ICI-EPI as a potential adverse effect in patients with malabsorption while on ICI and to risk-stratify patients with high-risk cSCC for prompt treatment and improved outcomes.