Giant intrapelvic malignant peripheral nerve sheath tumor mimicking disc herniation: A case report.

Giant intrapelvic malignant peripheral nerve sheath tumors arising in the sciatic nerve in the pelvic cavity are a rare occurrence and their symptomatology is usually misdiagnosed as intervertebral disc herniation. We herein report the case of a 46-year old woman presenting with pain, hypesthesia and weakness of the left lower extremity due to a giant intrapelvic malignant peripheral nerve sheath tumor of the sciatic nerve. Prior to being referred to our institution, the patient was misdiagnosed as a case of sciatica due to a lumbar disc herniation and underwent an operation unsuccessfully, as there was little symptomatic improvement 2 months after the surgery. A magnetic resonance imaging examination of the pelvic cavity revealed a tumor of the sciatic nerve. The mass was resected via the posterior approach and histopathological examination confirmed the diagnosis of malignant peripheral nerve sheath tumor. Intrapelvic malignant peripheral nerve sheath tumors are an uncommon cause of sciatica and are commonly misdiagnosed as lumbar intervertebral disc herniation. Accurate diagnosis and complete surgical excision prior to metastasis are crucial for effective management of this condition.