Undiff. Pleomorphic Sarcoma: Gross Pathology
Gross Pathology: Undifferentiated pleomorphic sarcoma is a solitary, large, fleshy, multilobulated mass, usually located deep within the skeletal muscles. The size ranges from 5 to 10 cm. The tumor appears grossly circumscribed, but it has a tendency to spread along the fascial planes, accounting for a high recurrence rate. Tumors located near a bone may erode the cortex or incite periosteal reaction. The cut surface is tan to gray to white. Tumors with numerous inflammatory cells (especially xanthoma cells) appear yellow. The presence of significant amount of hemorrhage may cause it to turn red or brown. Cases with myxoid stroma appear translucent and gelatinous. Necrosis and hemorrhage are frequent. When hemorrhage is extensive (about 5% of cases), the tumor may be converted into a fluid-filled sac resembling a hematoma. Image courtesy of Dr. K. V. Santosh, Bengaluru, India. Used with permission.