A 19-year-old man presented with chronic cough for 3 months and shortness of breath for 2 weeks. His vital signs were stable. His trachea was central. He had decreased air entry on right chest with dullness on percussion. Chest XR (Figure 1) showed a ‘white-out’ right lung. A computed tomography of the thorax was done (Figure 2) and it showed a large soft tissue mass in the anterior mediastinum, measuring 20 cm in diameter at level of carina. It has lobulated margins, with solid and cystic components, including foci of coarse calcification. There was no lymphadenopathy. He underwent percutaneous fine needle aspiration of the mass but it was not diagnostic. Both serum alpha-fetoprotein and B-hCG were markedly elevated at 16968 ug/L and 867 mIU/mL. Based on the characteristic thorax images and elevated tumor markers, extra-gonadal mediastinal primary germ cell tumor (non-seminoma) was diagnosed. The patient was started immediately on bleomycin, etoposide and cisplatin to decrease the tumor size followed by surgical debulkment.
The common causes of a ‘white-out’ unilateral lung on chest XR include complete collapse of one lung, massive pleural effusion and extensive consolidation. Rarely, a tumor in the lung or mediastinum can result in such chest XR finding.
Yeow Kwan Teo
