Nasopharyngeal angiofibroma is a tumor that grows behind the nose. Although it is a benign tumor (not cancerous), it is aggressive and serious. It can spread from the nasal cavity to the sinuses, eye socket, skull and brain. The nasopharyngeal angiofibroma tumor is made mostly of blood vessels, which can result in frequent nosebleeds. The condition is also called juvenile nasopharyngeal angiofibroma (JNA) because the vast majority of these tumors grow in adolescent males. Doctors also call it juvenile angiofibroma (JA).