A 65-year-old man presents to the emergency room complaining of intermittent hemoptysis for the past 1 week. He describes no chest pain, fever, cough, or chronic sputum production. He smokes 1 pack of cigarettes a day and has done so for the past 35 years. There are no risk factors for DVT or PE, and he is not taking any medications.On physical examination, his vital signs are normal, JVP is at 2 cm, heart sounds are normal, and the chest is clear on auscultation. There are no palpable lymph nodes and the remaining examination is normal. His sputum cytology is positive for malignant cells, but the CXR and CT chest are normal. Which of the following is the next best step in management?