A Giant Lipoma with Dedifferentiated Liposarcoma of the Thoracic and Dorsal Regions: A Case Report and Literature Review

A lipoma is a benign soft tissue tumor caused by the benign proliferation of mature adipose tissue. Tumors weighing over 1 kilogram or exceeding 5 centimeters in diameter are considered giant lipomas. Dedifferentiated liposarcoma, a highly malignant tumor derived from mesenchymal tissue, is a subtype of liposarcoma primarily found in the retroperitoneum. We report a rare case of a 56-year-old male patient who had a progressively enlarging massive tumor on his thoracic and dorsal regions over 10 years. Surgical excision was successful, and pathological examination revealed that most of the tumor showed mature lipoma changes, while a small area exhibited dedifferentiated liposarcoma changes.