Giant Retroperitoneal Schwannoma: Case Report and Review of the Literature.

Retroperitoneal schwannomas are rare benign tumors of peripheral nerve sheath origin. We report a 72-year-old woman presenting with abdominal pain, altered bowel habits, and intermittent fever. CT imaging revealed a large (83 × 83 × 104 mm), well-circumscribed retroperitoneal mass with calcifications and heterogeneous enhancement, without invasion of adjacent structures. Following multidisciplinary discussion among thoracic surgery, medical oncology, pathology, and radiation oncology, a midline laparotomy was performed, and the tumor was completely excised. Histology demonstrated Antoni A and B areas, cystic degeneration, and focal palisading. Immunohistochemistry was positive for SOX10 and negative for CD34, DOG1, and desmin, confirming schwannoma. The postoperative course was uneventful, and the patient was discharged on day 14. We also conducted a focused review.