Definition: Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.
Input: Abstract: A [99mTc]RBC study in a 63-yr-old man showed intrahepatic lesions which initially had less activity than surrounding liver tissue. When viewed 3 hr later, these had "reversed" and the lesions revealed increased uptake of the radiolabeled red cells. Some extrahepatic areas showed the same pattern (these were in the mesentery of the small bowel). The lesions proved to be angiosarcomas. Hence, the behavior of labeled red cells in these angiosarcomas mimicked that in benign hemangiomas.

Hepatic angiosarcoma: mimicking of angioma on three-phase technetium-99m red blood cell scintigraphy.