Aortic angiosarcoma clinically mimicking polyarteritis nodosa.

We report two patients in whom angiosarcoma of the aorta (ASA) with distal emboli and skin metastases was initially clinically misdiagnosed as polyarteritis nodosa (PAN). Both presented with features highly suggestive of systemic necrotizing vasculitis, including constitutional symptoms, orchitis (in one), leg pain with sensory neuropathy, livedo, focal areas of skin necrosis, painful cutaneous nodules demonstrating vasculitis or inconspicuous changes on biopsy, raised acute phase reactants, and transient improvement with systemic corticosteroids. Repeated skin biopsies revealed an atypical endovascular cell proliferation with strong reactivity for factor VIII. Magnetic resonance angiography (MRA) demonstrated an intra-luminal aortic tumour at the infra-renal level. In retrospect, the (PAN)-like features appeared to involve exclusively the lower part of the body in these patients.