Mazloom Sean E, Stallings Alicia, Kyei Angela
*Virginia Tech Carilion Dermatology and Mohs Surgery, Roanoke, VA; and †Cleveland Clinic, Dermatology and Plastic Surgery Institute, Cleveland, OH.
Am J Dermatopathol. 2017 Jan;39(1):33-39. doi: 10.1097/DAD.0000000000000574.
Reactive angioendotheliomatosis (REA) is a rare benign angioproliferative condition of the skin, which has been noted to occur in patients with a variety of underlying systemic diseases. Histopathologically, this condition is characterized by vascular proliferation, and endothelial cell hyperplasia within the lumina and around dermal vessels, without significant cellular atypia. Since the first case of RAE was reported in 1958, multiple histologic patterns of benign cutaneous vascular proliferations with similar clinical presentations to RAE have been described in the literature and have been proposed as subtypes of the originally described condition. Among these entities are diffuse dermal angiomatosis (DDA), acroangiodermatitis, glomeruloid angioendotheliomatosis, and angiomatosis associated with cryoproteins. It has also been proposed that another entity, characterized by the benign proliferation of histiocytes within the lumina of cutaneous vessels, is a subtype of RAE. Histiocytosis within dermal vessels, in conjunction with skin pathology, was first reported in 1994. Based on the appearance of involved vessels, it was initially believed that the histiocytic proliferations were within the lumina of capillaries. Hence, the term intravascular histiocytosis was introduced to describe this histologic finding. However, subsequent introduction of an immunohistochemical (IHC) marker specific for lymphatic vessels demonstrated that most cases of cutaneous histiocyte proliferation are intralymphatic, rather than truly intravascular. However, there have also been reports of IHC-confirmed cases of true intravascular (intracapillary) histiocytosis. In this study, clinical and histologic data from all of the cases of RAE and IHC-confirmed cases of intravascular histiocytosis and intralymphatic histiocytosis reported in the literature to date are examined. Through comparison of the frequency with which key clinical and histologic features present in cases of each group, the authors provide improved clarity of the similarities and differences between these 3 entities.
反应性血管内皮瘤病（REA）是一种罕见的皮肤良性血管增殖性疾病，已发现其发生于多种潜在全身性疾病的患者中。组织病理学上，该病的特征为血管增殖，以及管腔内和真皮血管周围的内皮细胞增生，无明显细胞异型性。自1958年首例RAE病例报告以来，文献中已描述了多种与RAE临床表现相似的良性皮肤血管增殖的组织学模式，并被提议作为最初描述疾病的亚型。其中包括弥漫性真皮血管瘤病（DDA）、肢端血管性皮炎、肾小球样血管内皮瘤病以及与冷球蛋白相关的血管瘤病。也有人提出，另一种以皮肤血管管腔内组织细胞良性增殖为特征的实体是RAE的一个亚型。真皮血管内的组织细胞增多症，连同皮肤病理学，于1994年首次报道。基于受累血管的外观，最初认为组织细胞增殖发生在毛细血管腔内。因此，引入了术语“血管内组织细胞增多症”来描述这一组织学发现。然而，随后引入的一种针对淋巴管的免疫组织化学（IHC）标记物表明，大多数皮肤组织细胞增殖病例是淋巴管内的，而非真正的血管内。不过，也有免疫组化证实的真正血管内（毛细血管内）组织细胞增多症的病例报告。在本研究中，对迄今为止文献报道的所有RAE病例以及免疫组化证实的血管内组织细胞增多症和淋巴管内组织细胞增多症病例的临床和组织学数据进行了检查。通过比较每组病例中关键临床和组织学特征出现的频率，作者更清晰地阐述了这三种实体之间的异同。
