Minimally invasive costotransversectomy for the resection of large thoracic dumbbell tumors.

Background: Due to their important size and complex localization, the management of thoracic dumbbell tumors is challenging, frequently requiring the need for an anterior approach. Our study aims to first report the feasibility and safety of a single-stage posterior minimally invasive procedure in achieving complete resection of voluminous thoracic dumbbell tumors.
Methods: We retrospectively reviewed the medical records of five consecutive patients, who underwent the minimally invasive resection of a type III thoracic dumbbell tumor in our institution between March 2007 and March 2012. There were two men and three women, with a mean age at diagnosis of 57 years (range 41-68 years). After the placement of a non-expandable tubular retractor under fluoroscopic control, a costotransversectomy was achieved. By moving the retractor in all directions, the tumor was largely exposed and resected with the cavitron ultrasonic surgical aspirator. Clinical and radiological monitoring was performed before discharge, at 6 months, 1 year and 2 years.
Results: No major intraoperative complication was reported. Gross total resection was achieved in four patients. The mean operative time was 219 mins (range 75-540 mins) and the mean estimated blood loss was 230 ml (range 50-500 ml). No postoperative complication was reported. The mean length of hospital stay was 3.6 days (range 2-6 days) and all patients were discharged home. Histological analysis confirmed the diagnosis of grade 1 schwannoma in four patients and revealed a hemangiopericytoma in one patient. No tumor recurrence was noted with a mean follow up period of 46 months (range 32-54 months).
Conclusion: Thoracic dumbbell tumors can be safely and completely resected using a single-stage minimally invasive procedure. The costotransversectomy can be performed through a non-expandable retractor allowing sufficient access to all parts of the tumor.