Adenopathy and extensive skin patch overlying plasmacytoma syndrome-the clue to early diagnosis of polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes: A case series and literature review.

Here, we present the second case series of three patients with adenopathy and extensive skin patch overlying plasmacytoma syndrome who all meet the diagnostic criteria for polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes. The diagnosis was suspected based on the presence of the violaceous cutaneous patch along with symptoms of systemic involvement (fatigue, weight loss, weakness). Dermoscopy revealing regular dilated parallel capillaries was suggestive of a benign/reactive vascular process. Histopathology in all three cases showed reactive vascular proliferation with a characteristic 90° branching. To date only 20 cases of adenopathy and extensive skin patch overlying plasmacytoma have been published, including ours. All patients presented with cutaneous lesions (violaceous patch and others) and most, at least 15/20, met the diagnostic criteria for polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes. When clinical follow-up was reported, most patients had a favorable prognosis with partial or complete symptom resolution following treatment of the underlying plasmocytoma.