Mediastinal Mass in a 25-Year-Old Man

A 25-year-old black man presented with left-sided chest pain and cough for 3 days. His pain was pressure-like and nonradiating and was aggravated with movement and relieved when the patient lay at a 45 degrees angle. The patient denied fevers, chills, night sweats, and swelling but reported gaining 4 to 6 kg (10 to 15 lbs) in the past few months. His cough had started 2 weeks prior with yellow mucus production but he denied facial swelling or tenderness. He had no chronic medical conditions and was not taking medications. He had no known exposure to chemicals, fumes, or dust and no history of tobacco or alcohol abuse.