A 52-year-old man with a 30-pack-year smoking history presents with chronic cough and recurrent respiratory infections. Bronchoscopic biopsy of the left mainstem bronchus shows columnar metaplastic epithelium with focal areas of nuclear enlargement, hyperchromasia, and loss of orderly maturation. The pathologist reports intestinal metaplasia with low-grade dysplasia. What is the most appropriate next step in management?