A 40-year-old man presents with a tender mobile subcutaneous nodule. On biopsy, pathology shows a well-circumscribed mass containing adipocytes with a prominent vascular pattern and occasional thrombi. What is the diagnosis?
C. The histologic description is characteristic of angiolipoma. Spindle cell lipomas contain bland-appearing spindle cells and normal adipocytes. Liposarcoma contains adipocytes and lipoblasts, and may stain for S100 (in one-third of cases). Pleomorphic lipoma contains bizarre multinuclated giant cells with normal adipocytes.
A 55-year-old man presents with a painless, rapidly enlarging subcutaneous mass on his thigh. Wide excision revealed a delicate plexiform capillary network containing lipoblasts, and normal adipocytes in a myxoid stroma. Under immunohistochemistry the cells stain positive for S100. What other location is this tumor typically found?
D. This is liposarcoma, the most common sarcoma in adults. It typically is found in the retroperitoneum, thighs, and inguinal region.
A 60-year-old obese woman presents with progressive onset of multiple painful subcutaneous nodules on her trunk, neck, and upper extremities. Biopsy revealed a diffuse infiltrate of adipose tissue into adjacent nerves and muscle. What other medical condition is this associated with?
D. Renal tubular acidosis
A. This is a description of Dercum disease (adiposis dolorosa). It classically presents in postmenopausal women and is associated with nervous system dysfunction and depression is often comorbid. Other conditions associated include obesity, dementia, confusion, weakness, and lethargy. Surgical management of lipomatosis and weight loss may help with symptoms.
A 38-year-old woman presents with progressive loss of subcutaneous fat on her face and torso. She denies recent changes in diet, medications, or illnesses. What labs should be checked?
A. Protein electrophoresis
B. This is acquired partial lipodystrophy associated with the C3 nephritic factor. This factor binds factor H, an inhibitor of C3 resulting in uncontrolled activation of C3 causing ...