Giant intramuscular thigh lipoma: A case report and review of literature

Introduction: Lipomas represent the most frequent type of soft tissue tumor. A giant lipoma is typically defined as a lesion measuring ≥10 cm in at least one dimension or weighing more than 1000 g.

While these tumors are often asymptomatic, they may occasionally produce compressive symptoms, including neuropathic pain or motor impairment, particularly when located in areas that affect gait or mobility.

Presentation of case: We report the case of a 48-year-old woman with no relevant past medical history who presented with a nine-year history of a progressively enlarging, painless mass on the right thigh. The lesion had gradually increased in size, leading to discomfort and limitation of daily activities. Magnetic resonance imaging (MRI) revealed a well-defined intramuscular , adipose mass measuring 26.5 × 12.5 × 6 depending on the rectus femoris muscle, well defined and encapsulated, with the same signals as fat.

Its lower pole reaches the myotendinous junction of the quadriceps, and its upper pole reaches the trochanteric massif.. Complete excision with clear margins was achieved while preserving the affected musculature. The postoperative course was uneventful, and the patient demonstrated a satisfactory functional recovery.

Discussion: Lipomas are common benign tumors originating from adipose tissue. Their considerable size or deep extension can pose challenges in surgical management. Although malignant transformation is rare, careful excision is warranted. Close collaboration between radiologists and surgical pathologists is essential, particularly in assessing muscular involvement and identifying any infiltrative growth patterns.

Conclusion: Giant lipomas should always prompt consideration of potential malignant transformation. Radiological assessment usually provides sufficient information to determine the necessity of a biopsy, thereby preventing unnecessary invasive procedures. During surgical excision, maintaining a margin of approximately 1 cm of healthy tissue is recommended to minimize the risk of local recurrence.