Intravascular Papillary Endothelial Hyperplasia Presenting as a Lateral Neck Mass.

Objective: 1) To present an abnormal presentation of intravascular papillary endothelial hyperplasia (IPEH) as a lateral neck mass. 2) Discuss typical pathologic and radiographic findings associated with IPEH. Method: Case presentation representing a patient who presented with a lateral neck mass. The ultimate pathologic diagnosis was IPEH, a rare benign condition. The typical radiographic and pathologic characteristics of this rare entity are presented and discussed. Results: IPEH is a proliferation of vascular endothelial cells that typically presents as a subcutaneous mass. In the aerodigestive tract it may also present as a tender submucosal nodule or a bluish, raised mucosal lesion. The mass manifested in IPEH represents an exaggerated growth response by endothelial cells as they respond to an inciting stimulus. It may present in a normal blood vessel, a vascular malformation, or in response to trauma. IPEH occurs in the setting of recannalization after thrombosis. IPEH shares many clinical and histopathologic features with angiosarcoma. It is important to differentiate this benign proliferative process from malignant disease. Conclusion: IPEH is a rare cause of a slowly growing neck mass. This condition is not a true neoplasm but rather reactive hyperplasia of the vascular endothelium. Diagnosis is based on micropathology and it is important to differentiate it from angiosarcoma. The primary curative management of these lesions is surgical excision.