Rapidly Growing Endobronchial Hamartoma With Bone Marrow Tissue

A 29-year-old woman presented with a 4 × 3.5 cm circumscribed mass located in the left upper lobe, which had not been detected in a chest roentgenogram that was taken 3 years prior. Bone scintigraphy using technetium-99m methylene diphosphonate revealed an increased uptake of the isotope in the mass, indicating increased osteoplastic activity. She underwent surgical resection of the mass and the pathologic diagnosis was endobronchially located pulmonary hamartoma, which contained bone marrow tissue. An extremely rare case of pulmonary hamartoma showing rapid growth and involving bone marrow tissue is presented.