Imatinib-Induced Classical Lichen Planopilaris in Blaschko-Linear Distribution Leading to Cicatricial Alopecia

A 27-year-old male with chronic myeloid leukemia (CML) developed classical lichen planopilaris (LPP) and atrophic lichenoid plaques in a blaschko-linear distribution, leading to cicatricial alopecia, after three months of treatment with imatinib. This case was the first reported instance of imatinib-induced LPP in such a distribution. The patient exhibited violaceous, atrophic, and alopecic plaques on the scalp, eyebrow, and forehead. Despite the psychological impact of visible lesions, the patient was advised to continue imatinib due to its life-saving nature. After switching to a different treatment and using topical mometasone furoate, the lesions did not progress. The exact mechanism of lichenoid eruptions from imatinib remained unclear, though they were thought to be dose-dependent.