[Vascular complication disclosing lung cancer in children].

Stroke are not as rare in pediatric patients as once suspected. Exhaustive diagnostic evaluation must be performed, to identify a cause, evaluate risk factors of recurrence and propose preventive treatment. We report a case in a teen-ager secondary to cerebral embolism. These embols have an exceptional origin: pulmonary venous thrombosis, secondary to undifferentiated sarcoma located in the lung and extended to pulmonary vein. Stroke by cerebral embolism are not always originated from heart disease, and may be misdiagnosed only transthoracic echocardiography is realised.