A 70-year-old white woman presented to the hospital for evaluation of shortness of breath and chest pain. Her dyspnea began 10 months ago and progressively worsened in the last 2 months. In the 48 h prior to admission, she also had right-sided pleuritic chest pain. She complained of cough with clear sputum for approximately 1 month, but denied hemoptysis, voice changes, or dysphagia. She reported weight loss of 15 pounds over the prior 3 months, as well as fatigue and occasional night sweats. She denied fever or chills. She smoked one pack of cigarettes a day for 15 years, until she quit smoking 30 years ago. She consumed two to three glasses of wine daily, until she quit 6 months ago. Her past medical history was significant only for hypertension. She had worked as a nurse, but denied any occupational exposures to animals, fumes, metals, or dusts.