Diffuse pulmonary hamartoma: a case report.

Pulmonary hamartoma usually occurs as a benign, well-circumscribed single nodule in the lung parenchyma. We report on a unique case of hamartoma that extended along the bronchial tree, formed endobronchial polypoid lesions, and expanded into the lung parenchyma. The patient, a 48-year-old man, was admitted with dyspnea and chest pain. A transbronchial biopsy was performed on a tumorous lesion that was diagnosed histologically as a hamartoma. As this lesion was found to be growing diffusely along the bronchial tree, a left pneumonectomy was performed. Gross examination showed that yellowish soft tissue had surrounded the bronchial tree and extended into the lung parenchyma. Histologically, the lesion contained mainly mature adipose tissue, cartilage, and muscle tissue with a minor component of short spindle cells in a myxomatous matrix. The patient was diagnosed as having diffuse pulmonary hamartoma.