She was aware of mild postnasal drip and had no symptoms of gastroesophageal reflux. Her exercise tolerance was normal. On physical examination, her chest had hard palpable masses over the right fifth and left third ribs. The remainder of the examination was normal. Routine complete blood count (CBC), liver function tests and chemistry, including calcium, were all normal. Office spirometry showed a forced expiratory volume in 1 s (FEV1) of 2.6 L/s and a forced vital capacity (FVC) of 3.2 L/s. A methacholine challenge was positive at 4 mg and showed mild to moderate airway hyperreactivity.
A chest radiograph showed two well-marginated masses within the thorax – 6 8 cm on the right side and 4.5 5 cm on the left side (Figure 2). The angle of junctions with the pleura was obtuse superiorly and acute inferiorly. A computed tomography (CT) scan confirmed the presence of the two masses, arising from the fifth right rib with displacement of the serratus anterior muscle and from the third left rib anterolaterally. Both masses contained internal septations of bone (Figure 3). Similar lesions were found in the lower thoracic vertebrae without expansion.
A diagnosis of asthma was made, and the patient was treated with inhaled fluticasone 250 g bid and salbutamol as required, with improvement in her symptoms. A two-year follow-up chest radiograph showed no changes in the size of the lesions, and the patient remains asymptomatic.