Uptake of technetium-99m methylene diphosphonate by a pulmonary hamartoma/mesenchymoma

Pulmonary hamartomas (or mesenchymomas) are benign developmental abnormalities of the lung, and are usually discovered as an incidental finding on a chest radiograph. Some exhibit characteristic “popcorn” calcification that may be recognized on plain chest radiography or standard tomography (Bateson et al, 1960), but computed tomography (CT) has been shown to be more sensitive in detecting calcification (Siegelman et al, 1980). Bone scanning using technetium-99m methylene diphosphonate (99Tcm MDP), a bone-seeking radiopharmaceutical, provides information that reflects skeletal metabolic activity. We report a case of pulmonary hamartoma in which a carcinoma developed in the contralateral lung. In the course of investigating the patient a bone scan was performed and radioisotope uptake by the hamartoma was observed. As far as we are aware this has not been described previously in a pulmonary hamartoma.