Successful Outcome in a Geriatric Patient With Giant Dedifferentiated Liposarcoma of the Lower Extremity: A Case Report

Liposarcomas are rare malignant soft tissue tumors; the dedifferentiated liposarcoma (DDL) subtype accounts for 6% of all soft tissue sarcomas. This tumor can develop de novo or transition from an atypical lipomatous tumor (ALT), occurring more frequently in the retroperitoneum; presentation in the extremities is uncommon. This subtype behaves aggressively, leading to local recurrence, metastasis, and a poor disease-free survival rate if treated improperly. We present the case of a 70-year-old female with a history of a giant soft tissue mass of one year of growth, with limited range of motion of her right lower extremity and edema. Initial histological analysis identified the mass as a well-differentiated liposarcoma/ALT. Post-surgical histological examination revealed a DDL, measuring 28 cm x 24 cm x 21 cm. Dedifferentiation from a well-differentiated tumor happens in approximately 10% of cases. Age, location, size, histological subtype, and presence of metastasis are the most important prognostic factors. Early suspicion of liposarcoma is paramount when facing a large, growing tumor in soft tissues; histological examination must be done to offer the proper treatment.