Pulmonary blastoma.

Pulmonary blastoma is now accepted as a distinctive neoplasm. It remains rare, and only 28 cases have been reliably recorded. A further two cases are now reported, and the previous literature is reviewed. There are no specific clinical or radiological features of pulmonary blastoma. The presentation can be that of any other pulmonary tumour although a peripheral situation is usual and a large size is often attained before detection. Pulmonary blastoma is a mixed tumour with malignant epithelial and connective tissue components with a distinctive resemblance to fetal lung. The treatment of choice is surgical excision but the overall prognosis is poor. It is doubtful whether the tumour has a true blastomatous origin.