Case report: pulmonary blastoma: presentation of two atypical cases and review of the literature.

Pulmonary blastoma is a relatively rare aggressive adult malignancy. The clinical and radiographic features of two cases are described and the literature reviewed. Pulmonary blastoma usually presents radiologically as a well-defined mass lesion on chest radiography, which may be large enough to completely opacify the hemithorax and cause mediastinal shift. On CT, pulmonary blastoma is seen as a mixed solid and cystic lesion with variable contrast enhancement and a necrotic centre. Pleural effusion may be present but is not the predominant abnormality. Our cases are unusual as recurrent pleural effusions in the absence of a significant lung mass were the presenting findings.