The surgical approach to "dumbbell tumors" of the mediastinum.

BACKGROUND

Successful management of posterior mediastinal dumbbell tumors depends on complete resection with adequate exposure. Correct preoperative assessment of neuroforaminal extension is important to avoid spinal cord injury. The surgical approach remains controversial.

METHODS

We report a retrospective analysis of posterior mediastinal dumbbell tumors over a 28-year period. All patients underwent one or more radiographic examinations available at the time of presentation and underwent a single-stage one-incision combined thoracic and neurosurgical procedure.

RESULTS

Among 16 patients aged 5 to 76 years, neuroforaminal involvement was identified before operation in 14 (87.5%) and during the procedure in 2 patients (12.5%). Computed tomography scan missed neuroforaminal involvement in 3 patients. Magnetic resonance imaging in 9 patients correctly identified neuroforaminal extension of the tumor but before MRI, myelography missed this extension in 3 patients. All patients underwent thoracotomy and posterior laminectomy was required in 10 of them. In 6 patients (38%) without laminectomy, resection required widening of the neural foramen in 3 whereas tumor was removed in 3 others through an already widened foramen. Spinal stabilization was required in 2 patients. There were 14 benign and 2 malignant lesions. Complete resection was performed in all patients without spinal cord injury or other major complication. No recurrences have been observed in a follow-up period from 2 months to 28 years (mean, 7.5 years).

CONCLUSIONS

Posterior mediastinal tumors should be evaluated for neuroforaminal involvement. A single-stage combined thoracic and neurosurgical approach is safe and leads to good long-term results. Laminectomy may be avoided in some patients.