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Planning of Surgical Management of Giant Spinal Schwannomas: Report of Four Cases

OBJECTIVE: Giant spinal schwannomas are rare tumors. Complete excision is recommended for these tumors because inadequate removal has a high risk of recurrence, which requires more definitive, difficult, and dangerous surgery. However, complete removal poses difficulties and combined multistage approaches may be necessary. METHODS: Four cases with giant spinal schwannomas were reported. Two of them were giant dumbbell tumors, and two were invasive type schwannomas. RESULTS: Two cases were operated by an anterolateral retroperitoneal approach, one by a lumbar posterior approach and instrumentation, and one with a thoracic tumor by costotransversectomy and laminectomy. In three cases, the tumors were totally removed. In the other case with a huge lumbar tumor treated by the anterolateral approach, the tumor could not be totally removed and a second stage was required but the patient refused the operation. CONCLUSION: In selected cases with giant spinal schwannomas, one staged posterior or anterolateral operation may be sufficient for complete removal of the tumor. Therefore, a cautious evaluation of the preoperative radiological examination is essential to plan the surgery and to avoid unnecessary operations. In addition, spinal stability must be evaluated preoperatively. Stabilization may be required especially when a posterior approach is planned for treatment of invasive type schwannomas extending into the vertebral bodies, and the paravertebral region.