Fig. 4.

Gross pathology (A), H&E stained sections ((B) and (C)), and progesterone stained section (D) of the tumor. Gross evaluation demonstrates a lobulated mass with a tan-gray and pink surface; normal yellow fat (arrows in (A)) is noted along the periphery. Histologically, the tumor is composed of a uniform distribution of bland-appearing spindle-shaped cells (B), with local invasion of the adjacent fat (asterisks). The lesion is highly vascular, with some blood vessels showing characteristic thickened walls (between straight arrows, (C)) and hyalinization surrounding the vessel walls (curved arrow, (C)). The tumor stained positive for both progesterone (D) and estrogen (not shown) receptors.