Liposarcoma

Liposarcoma is a cancer that arises in fat cells in soft tissue, such as that inside the thigh or in the retroperitoneum. It is a rare type of cancer that bears a resemblance to fat cells when examined under a microscope. It is typically a large, bulky tumor, and tends to have multiple smaller satellites that extend beyond the main confines of the tumor. Liposarcomas, like all sarcomas, are rare.Medical ultrasonography of a liposarcoma: In this case a heterogeneous mass consisting of an upper hyperechoic portion, corresponding to lipomatous matrix, and areas of hypoechogenicity corresponding to nonlipomatous components.Ultrasonography of a liposarcoma mimicking a lipoma. A homogeneous hypoechoic mass presenting with the same appearance of lipoma. It was clinically distinguished as having rapid growth.Micrograph of a myxoid liposarcoma, H&E stainMicrograph of a dedifferentiated liposarcoma, H&E stain Liposarcoma is a cancer that arises in fat cells in soft tissue, such as that inside the thigh or in the retroperitoneum. It is a rare type of cancer that bears a resemblance to fat cells when examined under a microscope. It is typically a large, bulky tumor, and tends to have multiple smaller satellites that extend beyond the main confines of the tumor. Liposarcomas, like all sarcomas, are rare. Patients usually note a deep-seated mass in their soft tissue. Only when the tumor is very large do symptoms of pain or functional disturbances occur. Retroperitoneal tumors may present themselves with signs of weight loss and emaciation and abdominal pain. These tumors may also compress the kidney or ureter, leading to kidney failure. The diagnosis is established by histologic examination of the tissue, i.e., biopsy or excision. Lipoblasts are often present; these are cells with an abundant clear multivacuolated cytoplasm and an eccentric darkly staining nucleus that is indented by the vacuoles. Ultrasonography may not be able to distinguish a liposarcoma from a benign lipoma, and therefore, MRI is the initial imaging of choice.