A man with a cough who couldn't sleep on his left side

This 40-year-old white male construction worker was referred to our university medical center to rule out lung cancer. He had seen his family physician 4 months before for an upper respiratory infection. His symptoms included cough, fever, night sweats, and a temperature of 102°F. He was treated with antibiotics, and the acute illness resolved, but a nonproductive cough continued. When we saw him, his blood pressure was 150/90 mm Hg; pulse rate, 80; and respiration, 17-18 breaths per minute. He said the cough was exacerbated by lying on his left side and relieved by lying on his right side, the only position in which he could sleep. He had no hemoptysis, pleuritic pain, or history of tuberculosis. He said he lost about 1015 lb over the 4-month period. A single posteroanterior (PA) chest radiograph revealed a left lung mass, which prompted his referral to our center. On admission, pertinent findings of his physical examination were diminished breath sounds and wheezing at the left lung base. A routine laboratory workup detected proteinuria (2+ to 4+)