Perifollicular Xanthoma Occurring in Patients after Erlotinib Treatment.

Erlotinib (Tarceva) is a drug used for the treatment of non-small cell lung cancer in patients with epidermal growth factor receptor (EGFR) mutations. Since EGFR is expressed in the skin, EGFR inhibitors commonly develop cutaneous side effects such as acneiform eruption, paronychia, telangiectasias, and abnormal eyelash growth. A 56-year-old man and a 46-year-old man visited the dermatology clinic complaining of yellowish papuloplaques and acneiform eruption on the face. They had been treated with erlotinib for lung cancer. Since patients using EGFR inhibitors are increasing, physicians should be aware that xanthomatous change can occur in severe acneiform eruptions after erlotinib treatment.