Pulmonary blastoma, a true congenital neoplasm.

An infant, after a difficult delivery, had X-ray shadowing in the right lung. After 32 days sudden death occurred, a pulmonary blastoma being found at autopsy. The controversy over whether this tumour is a blastoma or a carcinosarcoma is discussed and arguments are advanced for acceptance of the designation pulmonary blastoma when the tumour occurs in infancy and childhood. When the equivalent tumour occurs in adults with or without the addition of areas of carcinoma and/or sarcoma, the title 'mixed tumour of lung' should replace the term carcinosarcoma.