Pulmonary blastoma: a rare childhood malignancy.

Pulmonary blastoma is a rare primary malignancy of the lung, with few cases reported in children. The tumor consists of mesenchymal and epithelial components resembling the fetal lung. Seven children (aged 18 months to 5 years) with pulmonary blastoma were studied. The pulmonary radiographic patterns seen were a large, space-occupying solid mass with opacification of the hemithorax and preexisting cystic disease with a small solid tumor component. Computed tomographic images showed a low-attenuation mass with whorls of high-attenuation solid tissue. Four of the seven patients died within 2 years despite surgery and therapy; of the three surviving patients, one has recurrent disease.