Joint clues to a silent killer: hypertrophic osteoarthropathy and lung cancer.

A 54-year-old chronic smoker presented with dyspnea, chronic cough, digital clubbing, and painful forearm swelling. Imaging revealed periosteal new bone formation and a pleural-based lung mass with high FDG uptake. Biopsy confirmed lung adenocarcinoma with secondary hypertrophic osteoarthropathy. The patient was started on Pemetrexed and Paclitaxel chemotherapy and remains under oncology follow-up.