Giant retroperitoneal schwannoma from the fifth lumbar nerve root with vertebral body osteolysis: a case report and literature review

Study design  To report a rare case of retroperitoneal schwannoma from lumbar nerve root with difficult surgery and potential vascular complication. Objective  We report a rare case of giant schwannoma which arises from fifth lumbar root with L5 vertebral body destruction. Summary of background data  Retroperitoneal schwannomas are rare, and those with bony involvement are even rarer and may be mimicking malignant tumors. Methods  Retroperitoneal removal of the tumor with partial killing of right L5 nerve root and allograft of L5 vertebral body defect were performed. Incidental injury of common iliac vein was encountered due to adhesion of the vein to tumor capsule. The laceration was repaired by cardiovascular surgeon. Results  At final follow-up, the patient had mild weakness of dorsi-flexion of right ankle and mild right L5 dermatome numbness. No walking difficulty and no sign of local recurrence in the image studies. Conclusions  Retroperitoneal schwannomas are rare, and they can become very large when diagnosed. Major vessels impingement and adhesion can occur which make the surgery difficult. Careful pre-operative evaluation and explanation is very important.