Pulmonary blastoma.

Pulmonary blastoma is a rare primary malignant lung neoplasm, originating from multipotential pulmonary cells composed of immature mesenchyme and epithelium, which is morphologically similar to fetal lung tissue. It represents 0.25% to 0.5% of all primary lung tumors. There are no specific clinical features that differentiate this tumor from common lung neoplasm. We are reporting a case of pulmonary blastoma in a 70 years old male, cigarette smoker. He had initial diagnosis of hydatid cyst for which thoracotomy was done. Operative findings revealed a mass lesion in right lung involving oblique fissure. Biopsy showed malignant neoplasm with predominant sarcomatous (rhabdoid) component suggestive of pulmonary blastoma of biphasic type.