Abstract
Pulmonary Langerhans cell histiocytosis (PLCH) is a rare neoplastic condition that occurs almost exclusively in young smokers and presents with multiple solid and/or cystic nodules in a primarily upper lobe distribution on chest imaging. Frequently, suspicion arises incidentally on imaging performed for alternative reasons, such as lung cancer screening, but diagnosis requires biopsy studies. We describe an uncommon case of PLCH in an elderly female patient presenting with mild dyspnea and a significant history of smoking. Diagnosis was made with a biopsy of a new pulmonary nodule in her left lung found on lung cancer screening computed tomography (CT) scan. No gold standard therapy exists, and novel agents are being studied for future use. At present, she has been advised to quit smoking and is being followed with serial imaging studies to determine additional measures.