Silently Wrapped: Embolization and Surgical Strategy for Giant Sciatic-Sparing Myxoid Liposarcoma-Case Report.

Abstract

Background and Clinical Significance: Myxoid liposarcoma (MLS) is a malignant soft tissue tumor that often presents as a painless, slow-growing mass and is known for its atypical extrapulmonary metastatic pattern. Although sciatic nerve involvement is rare, when present, it usually causes neurologic symptoms. In this case, a large MLS silently expanded and completely encased the sciatic nerve without causing deficits, highlighting the importance of early imaging, multidisciplinary planning, and individualized surgical strategy in managing complex soft tissue sarcomas. Case Presentation: This case report describes a 67-year-old male with a 30 cm encapsulated myxoid liposarcoma of the posterior left thigh. The tumor had grown insidiously over one year and completely encased the sciatic nerve without causing pain, paresthesia, or motor impairment. Selective embolization was performed preoperatively to minimize blood loss. A posteromedial surgical approach allowed for en bloc resection with negative margins and preservation of sciatic nerve integrity. Histopathology confirmed a myxoid liposarcoma composed primarily of spindle-shaped tumor cells. The patient experienced no postoperative complications or neurologic deficits. At the two-year follow-up, he remains disease-free with full functional recovery. Conclusions: This case illustrates the potential for large, asymptomatic myxoid liposarcomas to encase critical neurovascular structures without infiltration. Preoperative embolization as part of a multidisciplinary plan was key to achieving safe resection and excellent functional outcomes.