Intravascular Papillary Endothelial Hyperplasia (Masson's Tumor) of the Supraclavicular Region: Management of a Rare Case.

BACKGROUND Masson's tumor, also known as IPEH (intravascular papillary endothelial hyperplasia), is a rare benign vascular process, comprising approximately 2% of vascular tumors of the skin and subcutaneous tissue. IPEH presenting as a neck mass is rare, with only 5 reports of anterior neck mass and 7 cases of lateral neck lesions, of which 1 was in an external jugular vein aneurysm. To the best of our knowledge, the localization of intravascular papillary endothelial hyperplasia in the supraclavicular region is rarely reported.