Pemigatinib-Associated Psoriasis in a Patient With Cholangiocarcinoma.

Psoriasis is a chronic autoimmune skin disease that may be triggered or exacerbated by medications, including targeted oncologic therapies. Pemigatinib is a fibroblast growth factor receptor inhibitor used for the treatment of cholangiocarcinoma. We present the case of a 61-year-old woman with unresectable cholangiocarcinoma and lung metastases who developed psoriatic plaques after four cycles of pemigatinib. She had a remote history of limited psoriasis but no other new triggers. Her presentation included occipital scalp and leg plaques. Topical therapies were prescribed; however, follow-up revealed persistent disease and uncertain treatment adherence. The patient ultimately deprioritized dermatologic symptoms in the context of systemic illness. To our knowledge, based on searches in PubMed and other databases, this represents the first reported case of pemigatinib-induced psoriasis. Recognition and management of dermatologic adverse effects are critical to minimizing morbidity in the setting of life-prolonging oncologic treatments. Given the limitations of a single-case inference, further surveillance and study are needed to determine whether patients with pre-existing psoriasis may be at increased risk.