Wilk Michael, Zelger Bettina G, Debiec-Rychter Maria, Sciot Raf, Zelger Bernhard
Dermatohistological Laboratory, P.O. Box 4145, 90021, Nuernberg, Germany.
J Dtsch Dermatol Ges. 2015 May;13(5):441-8. doi: 10.1111/ddg.12600.
Angiomatoid fibrous histiocytoma (AFH) is a rare, low-grade malignant, subcutaneous neoplasm in children or young adults.
AFHs in different disease stages were studied histologically, in part, also immunohistologically, and by fluorescence in situ hybridization.
Depending on the degree of fibrosclerosis, nine AFH were divided into the following categories: classic type (n = 3): well-defined subcutaneous lesions composed of multinodular spindle to epithelioid (histiocytoid) cells surrounding a pseudoangiomatous space filled with blood. Peripherally, there is a fibrous pseudocapsule and an inflammatory infiltrate. Early sclerotic type (n = 4): the fibrous capsule extends more to the inner circle of the lesion, focally replacing the cellular neoplastic component and pseudoangiomatous spaces. Late sclerotic type (n = 2): the architecture of AFH with its zonal arrangement of an outer fibrous and inner cellular component is largely replaced by fibrosis occluding the pseudovascular space in the center of the lesion. Immunohistochemistry was available in 5/9 cases with positivity for EMA (5/5), desmin (3/5), caldesmon (1/2), and CD99 (2/5). One of two cases tested displayed EWSR1 rearrangement.
Late-stage AFH may present with marked fibrosis obscuring the real nature of the lesion and may easily be misinterpreted by the unwary as a harmless fibrotic condition.
血管样纤维组织细胞瘤（AFH）是儿童或年轻人中一种罕见的低度恶性皮下肿瘤。
对处于不同疾病阶段的AFH进行组织学研究，部分还进行了免疫组织化学和荧光原位杂交研究。
根据纤维硬化程度，9例AFH分为以下几类：经典型（n = 3）：边界清晰的皮下病变，由围绕充满血液的假血管瘤样腔隙的多结节状梭形至上皮样（组织细胞样）细胞组成。外周有纤维性假包膜和炎性浸润。早期硬化型（n = 4）：纤维性包膜更多地延伸至病变的内圈，局灶性取代肿瘤细胞成分和假血管瘤样腔隙。晚期硬化型（n = 2）：AFH的结构及其外层纤维和内层细胞成分的带状排列在很大程度上被纤维化所取代，纤维化封闭了病变中心的假血管腔隙。9例中有5例进行了免疫组织化学检测，结果显示EMA（5/5）、结蛋白（3/5）、钙调蛋白（1/2）和CD99（2/5）呈阳性。检测的2例中有1例显示EWSR1重排。
晚期AFH可能表现为明显的纤维化，掩盖了病变的真实性质，粗心的人可能很容易将其误解为无害的纤维化情况。
