As a resident, you see a 58-year-old, Latino man who comes to your clinic with a 2 month history of cough, headache, light-headedness, nasal congestion, weight loss, and facial swelling. Other than his being a cigarette smoker, you do not know his past medical history because his interpreter is not available at the time of your interview of him. On the way to getting the interpreter, you come across your clinic attending physician who asks you for a brief presentation on the patient. Now you are asked what you think of the patient’s diagnosis. You insist that you have not finished a whole interview and physical examination yet. However, the attending physician says, “Oh, we already know his problem, don't we?”
What is the most likely diagnosis? What test do you order first?