FIG. 4. Original magnification ×1.25 ( A ) and ×10 ( B ). Hematoxylin and eosin stain demonstrates hypercellular stroma, which consisted of spindle cells with thin-walled microvessels, staghorn vessels, and collagen fibers ( asterisks ), were shown. There were also dilated vessels with blood cells inside that formed cystic cavity ( arrowheads ).