Question
A 22-year-old man was referred to us for evaluation of an asymptomatic abnormality detected on chest radiography performed during a physical screening before the start of military service. He was a nonsmoker, had no pulmonary symptoms, and was otherwise well.
Where is the abnormality on this chest radiograph?
Left lower lobe
Left upper lobe
Right lower lobe
Right upper lobe
Superior mediastinum
Show Correct.Answer
Correct Answer : Left upper lobe
Explanation : A pulmonary mass is visible in the left upper lung.
Nonenhanced computed tomography (CT) of the chest revealed a well-defined mass, 3 cm in diameter, in the left upper lobe, containing multiple calcifications .A magnified image of the mass showed calcifications of a linear, nodular, irregular shape, known as “popcorn” calcifications. The CT findings were highly suggestive of pulmonary chondroid hamartoma. Pathological examination of tissue obtained by means of percutaneous biopsy revealed cartilage and spindle-cell mesenchymal stroma, confirming the diagnosis. Two years later, the patient remains well, and the tumor is unchanged. Pulmonary hamartoma is a benign lung tumor that should be considered when an incidental solitary pulmonary nodule is identified. Popcorn calcifications within a well-circumscribed pulmonary nodule are highly suggestive of pulmonary chondroid hamartoma.
Created by USMLE PlAB MCQ
Created by USMLE PlAB MCQ
