Congenital pulmonary myofibroblastic tumor: a case report with cytogenetic analysis and review of the literature.

We report a case of congenital pulmonary myofibroblastic tumor, and review prior reports of this rare neoplasm to demonstrate its clinically benign behavior despite histologic features previously interpreted as sarcoma. The patient, a female neonate, presented with severe respiratory distress after cesarean section delivery. A large radio-opaque mass was detected in the right hemithorax and resected by right bilobectomy. The tumor mass, confined to the lung, was composed of interlacing fascicles of plump spindle cells showing myofibroblastic differentiation and complex cytogenetic abnormalities. Though sarcomatous in appearance, with highly cellular areas and numerous mitoses, there has been neither tumor recurrence nor metastases. The patient remains alive and well 1 year after surgery. Review of the few other reported cases confirms the uniformly benign behavior of this tumor.