Background: Aneurysms are the most frequent cause of a pulsating vascular tumor. Rarely does one have to take under consideration a vascular neoplasm in differential diagnosis.Case Report: A 41-year old man with a subclavicular pulsating tumor and a suspicion of right subclavian artery pseudoaneurysm is presented. The patient underwent several open biopsies and a lymphadenectomy which did not conclude to a final diagnosis. A well-vascularized tumor connected to the right subclavian artery and compressing the right subclavian vein was observed in duplex scan examinations, arteriography and NMR. The tumor had no features of a typical pseudoaneurysm. The tumor was excised along with the adjacent artery and replaced with a synthetic vascular prosthesis. The final pathology reportrevealed a haemangioendothelioma epithelioides – a rare vascular neoplasm.Conclusions: Presence of vascular neoplasm should be considered, especially when results of investigations are not obvious.

Keywords: vascular tumor, haemangioendothelioma epithelioides, pseudoaneurysm