Acute Macrocystic Thoracic Schwannoma: Systematic Review and Illustrative Case Example.

BACKGROUND: Schwannomas are benign peripheral nerve sheath tumors arising from myelinating Schwann cells. Although macrocystic changes are regularly encountered in schwannoma variants such as vestibular nerve tumors, they are exceedingly rare among spinal neoplasms.

METHODS: Case report and systematic review of four databases (Ovid Medline, PubMed, Science Direct, and SCOPUS) from inception to present. All peer-reviewed publications reporting intradural cystic thoracic schwannoma were included.

RESULTS: We identified 8 publications documenting 9 cases of cystic thoracic schwannoma. Four were female, five male; median age was 41 years (range, 27-80). Presentations ranged from incidental to pain, sensory changes, lower extremity paresis, or bowel/bladder dysfunction. Characteristic radiographic findings included T1 hypointensity, T2 hyperintensity, and cord effacement or compression. The present case followed a similar pattern: a 52-year-old male presented with worsening bilateral lower extremity weakness, low back pain, and gait dysfunction, worsening over three days. Examination also revealed decreased left lower extremity sensation. Imaging identified a well-delineated intradural, extramedullary macrocystic extending over T7-T10. The patient underwent a laminectomy resulting in complete tumor resection and restoration of intact neurological function. Final pathology confirmed benign cystic schwannoma.

CONCLUSION: Macrocystic thoracic schwannomas are exceedingly rare, and lack a comprehensive scheme for clinical classification of their natural history and pathogenesis. We report the 10th case of such a schwannoma, and the first associated systematic review. Although macrocystic thoracic schwannomas are not frequently encountered, accurate diagnosis and appropriate neurosurgical treatment is critical in these vulnerable patients, given the opportunity for excellent functional outcomes following neurosurgical treatment.