Giant well-differentiated liposarcomas of the gluteal region: A case report.

RATIONALE: Well-differentiated liposarcoma (WDL), a rare mesenchymal tumor with adipocytic differentiation, represents a distinct subtype of liposarcoma (LPS). It demonstrates relatively high incidence and typically arises in the deep soft tissues of the extremities, retroperitoneum, or cervical regions. This case report presents a 55-year-old female patient with a 12.0 cm × 9.0 cm × 6.5 cm tumor in the right gluteal region, which was successfully managed with surgical resection in the absence of distant metastasis. PATIENT CONCERNS: A 55-year-old female patient was admitted to our hospital due to right gluteal swelling accompanied by progressive ipsilateral lower limb soreness and numbness for 3 days, which worsened with activity and alleviated at rest, leading to difficulty in walking. Based on clinical manifestations, physical examination, and imaging findings, a preliminary diagnosis of gluteal liposarcoma was considered. DIAGNOSES: Histopathological analysis definitively diagnosed a giant WDL located in the right gluteal region. INTERVENTIONS: The lesion was completely removed with marginal resection, achieving en bloc excision along the plane outside the tumor capsule. OUTCOMES: The patient was discharged on postoperative day 14 without complications. Telephone follow-up at 1, 3, 6 months, and 1 year postoperatively, along with ultrasound and magnetic resonance imaging examinations, revealed no evidence of recurrence. LESSONS: WDL represents a rare neoplastic entity. Due to its nonspecific clinical presentation and diagnostic inexperience, definitive preoperative diagnosis remains challenging. Accurate diagnosis of WDL relies on comprehensive histopathological examination, immunohistochemical profiling, and molecular analysis. Our findings underscore the critical importance of surgical intervention to prevent neurovascular complications and optimize clinical outcomes.