A 47-year-old man attended the emergency department complaining of shortness of breath and palpitations. He had felt generally unwell over the preceding weeks, with a dry cough, dyspnoea, unintentional weight loss and fatigue. His past history included a resected gastric carcinoma (T4, N1, M0), and asthma, which had been present since childhood. He took 40 mg omeprazole OD and used a salbutamol inhaler several times daily. He had previously worked as a laboratory technician but was currently unemployed. He had no recent travel history. He was a current smoker with a 40 pack year history and did not drink alcohol.