Dumbbell neurogenic tumors of the mediastinum. Diagnosis and management.

Among 706 collected cases of mediastinal neurogenic tumors were 69 patients (9.8%) with extension through an intervertebral foramen, so that the composite neoplastic mass was dumbbell-shaped. Although only 10% of these dumbbell tumors were malignant, the majority of the patients presented with neurologic symptoms of spinal cord compression. In about 40% of reported cases, the intraspinal component, although present, was not clinically apparent. Such cases of asymptomatic intraspinal extension should be suspected when special roentgenologic views of the spine demonstrate erosion of the vertebral pedicle or enlargement of the intervertebral foramen adjacent to the posterior mediastinal mass. Workup of these patients should include myelographic studies to determine whether a dumbbell tumor is indeed present; if it is, surgery should be carried out by a team of thoracic surgeons and neurosurgeons in a one-stage combined resection of both the intraspinal and the mediastinal component of the tumor. With early diagnosis and surgical intervention, long-term survival is the rule. When the patient is in the pediatric age bracket, an orthopedic surgeon should be included on the team to help minimize subsequent skeletal growth deformity.