Fade to black!

A 71-year-old man presented to the emergency room with chest pain, dry cough, shortness of breath and night sweats for 10 days. He had no fever, flu-like symptoms, sputum production or haemoptysis. There was no history of recent travel or sick contacts. A general review of systems was remarkable for subjective weight loss and malaise. He was an active smoker with a 100 pack-years smoking history and a past medical history of rectal squamous cell...