Giant cystic schwannoma of the cauda equina

Long Completely Cystic Sciatic Schwannoma: A Rare Case

Schwannomas are the most common peripheral nerve sheath tumors. Benign schwannomas with malignant transformation are rarely reported. Most common schwannomas occur in the head and neck region. Sciatic schwannomas are rare, as are completely cystic schwannomas. Sciatic nerve schwannomas represent less than 1% of all schwannomas. Benign tumors in the sciatic nerve consist of 60% neurofibromas and 38% schwannomas. In general, a schwannoma induces chronic symptoms. It can be misleading, sometimes mimicking degenerative spinal pathology due to disc herniation. Schwannoma involving the sciatic nerve can be asymptomatic or may present with sciatica or neurological deficits. Most schwannomas are solid or heterogeneous tumors, and completely cystic schwannomas are rare. The differential diagnoses of nondiscogenic sciatica include lumbar disc herniation, tumor, abscess, hematoma, facet syndrome, lumbar instability, sacroiliitis, piriformis syndrome, and sciatic neuritis. We report a rare case of a long completely cystic sciatic schwannoma in the left foraminal L5–S1 zone extending to the left ischial groove with chronic sciatica that was diagnosed radiologically with a combination of conventional MRI and MR neurography and confirmed histopathologically by surgical resection. The patient previously had conservative therapy, but the complaints were not reduced. Nonsurgical therapy is considered the first choice, and surgical therapy is indicated in cases that do not respond to conservative therapy, with recurrent cysts, severe pain, or neurological deficits.

Thoracic cystic schwannoma: case report and review of literature

INTRODUCTION

Schwannomas are the second most common type of intra-dural lesions involving the thoracic spine. They are frequently seen as solid and heterogeneous lesions. Totally cystic thoracic schwannomas represent a rare pathological schwannoma variant, with only four cases reported in the English literature to our knowledge.

CASE PRESENTATION

We report an 80-year-old male who presented with upper back pain for 3 months. Magnetic resonance imaging (MRI) showed a cystic lesion at the level of T6-T7 with peripheral contrast enhancement. The lesion was removed in total surgically with complete resolution of the patient's symptoms.

DISCUSSION

The diagnosis of cystic schwannomas is often delayed due to the paucity of symptoms and the lack of meticulous investigation. The presence of rim enhancement on contrast-enhanced MRI may be the only clue for the diagnosis. It is important to consider cystic schwannomas in the differential diagnosis of cystic spinal lesions since the best surgical outcome is strongly related to earlier diagnosis and total resection of the lesion.