Erlotinib-Related Severe Hair Loss with Severe Exanthematous Drug Eruption: A Case Report

A 54-year-old woman with metastatic non-small-cell lung cancer experienced severe hair loss and erythematous skin patches after starting erlotinib, a drug that inhibits the epidermal growth factor receptor. Histopathological examinations revealed significant infiltration of immune cells in the skin and scalp. Discontinuation of erlotinib led to improvements in both hair loss and skin lesions. While hair loss occurred in 5% of patients on erlotinib, this case was notable for complete baldness and an exanthematous drug eruption, which had not been previously reported as a side effect of erlotinib. The findings suggested a possible link to erlotinib hypersensitivity.