%0 Journal Article %T Reci¨¦n nacido con masa pulmonar de etiolog¨ªa infrecuente %A Pellegrino Cid %A Christian %A Maglio %A Silvana %A Gentile %A Luis Fernando %J Archivos argentinos de pediatr£¿-a %D 2012 %I Sociedad Argentina de Pediatria %X thoracic masses in neonates usually respond to congenital anomalies of the respiratory system. they comprise a large number of diseases that can compromise the development of larynx, trachea, bronchi, pulmonary parenchyma and diaphragm or chest wall. diagnosis is carried out during prenatal period by ultrasound in most cases. in others, respiratory distress is diagnosed during post-birth examination or later as a radiological fnding. we present the case of a full term newborn with prenatal diagnosis of cystic "lung mass". physical examination was unremarkable except for decreased breath sounds on the right lung. different image studies were carried out to characterize the lesion. the patient underwent surgery and chemotherapy at ffth month of life. pleuropulmonary blastoma diagnosis was confrmed by pathological study of the surgical specimen. this is a rare intrathoracic malignant tumor, appearing almost exclusively in children less than 7-years-old. %K pleuropulmonary blastoma %K chest mass in neonates. %U http://www.scielo.org.ar/scielo.php?script=sci_abstract&pid=S0325-00752012000300016&lng=en&nrm=iso&tlng=en