HSS Ultrasound of the Month Case 126

Clinical History 74 year old female with a growing painful mass just below the knee.

Ultrasound of the Month – Case 126

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Ultrasound of the Month – Case 126

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Ultrasound of the Month – Case 126

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Ultrasound of the Month – Case 126

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Diagnosis: High-grade Pleomorphic Sarcoma of the Lower Leg Undifferentiated pleomorphic sarcoma (UPS), formerly known as malignant fibrous histiocytoma (MFH), is the most common soft tissue sarcoma in adults with an aggressive behavior and poor prognosis.

They have a predilection for the lower and upper limbs, but can also arise in the retroperitoneum or the peritoneal cavity.

Clinically, these tumors present as a rapidly growing mass.

Most UPS are of high grade (grades 3 and 4), will have frequently metastasized at time of diagnosis, and can locally recur even with aggressive treatment.

MRI is the imaging modality of choice for assessing these tumors.

Ultrasound will show a nonspecific solid mass, but ultrasound has the advantage of allowing for image-guided soft tissue biopsy should a tissue diagnosis be required.

Ultrasound of the Month – Case 126

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