Li-Min Lao, Masanobu Kumakiri, Takahiro Kiyohara, Keiko Sakata, Akiteru Takeuchi
DOI: 10.1080/00015550410024120

This is a report of papillary endothelial hyperplasia in a 9-year-old girl with a pilomatricoma showing bullous appearance. Histologically, papillary proliferation of endothelial cells was found within dilated lymphatic endothelium-lined vascular channels overlying a pilomatricoma. The endothelial cells covering the papillae were of a lymphatic endothelial cell nature proved by immunohistochemistry and electron microscopy. Abundant fibrous long-spacing collagen was observed in the connective tissue and fibroblasts within papillae.