Sciatic nerve schwannoma: Case report

Background. Schwannomas are common, benign tumors of the sheath of peripheral nerves. Sciatic schwannomas are rare. PURPOSE: We report a case of a large sciatic schwannoma, emphasizing the role of nerve preservation. Material & methods. A 54 years old female was admitted in our clinic for persistent right sciatalgia, and right L5 and S1 motor loss, symptoms lasting for almost 2 years. Patient underwent surgery in a different department, but the operation was stopped, because of excessive bleeding. Results Neurological examination revealed right sciatalgia, right L5 and S1 motor loss and diminished ankle jerk reflex, but failed to reveal relevant symptoms for disc herniation clinical diagnostic. Thigh CT-scan and MRI showed a large (70/80/75 mm) encapsulated, contrast-enhancing tumor, located in the middle third of the posterior thigh, in intimated relation with the sciatic nerve. Associated chronic myeloproliferative syndrome required oncological treatment and surgery postponement. We performed a subtotal resection of a large, solid tumor, infiltrating the sciatic nerve on 4 cm length, with anatomic integrity of sciatic preservation. Histopathological examination found cellular schwannoma. Outcome was favorable, and on follow-up examination the patients present no additional deficits and thigh CT-scan showed any evidence of tumor regrowing. Discussions & Conclusions. Diagnostic is challenging, in many symptoms are attributed to degenerative spinal pathology. Any persistent sciatlagia, with irrelevant lumbar MRI must raise the suspicion of a peripheral sheath tumor, and must be further investigated. Surgery is very demanding and associated co-morbidities must be treated prior surgery. Preserving the integrity of the sciatic nerve, assure favorable outcome, with no additional neurological deficits