Abstract
Langerhans cell histiocytosis (LCH) is a rare neoplastic disease characterized by infiltration of histiocytes and dendritic cells into body organs. While treatment is better established in pediatrics, there is still no consensus on therapy in the adult population. Imatinib has shown promising results in some case reports and a small clinical trial. We present here a fifty-nine-year-old patient with LCH in the lung, liver, and bone who responded well to an imatinib dose of 100 mg daily. Her symptoms improved within 3 months of treatment, and subsequent positron emission tomography-computed tomography (PET/CT) showed resolution of 18F-fluorodeoxyglucose (FDG)-avid lesions.