Yamada Yuichi, Kinoshita Izumi, Kohashi Kenichi, Yamamoto Hidetaka, Kuma Yuki, Ito Takamichi, Koda Kenji, Kisanuki Atsushi, Kurosawa Manabu, Yoshimura Michiko, Furue Masutaka, Oda Yoshinao
Department of Anatomic Pathology, Pathological Sciences, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka-ken, 812-8582, Japan.
Department of Pathology, Fujieda Municipal General Hospital, 4-1-11 Surugadai, Fujieda-shi, Shizuoka-ken, 426-8677, Japan.
Virchows Arch. 2017 Jul;471(1):117-122. doi: 10.1007/s00428-017-2122-2. Epub 2017 May 6.
Ischemic fasciitis is a benign myofibroblastic lesion, occurring in the sacral region or proximal thigh of elderly or bedridden individuals. The pathogenesis of ischemic fasciitis is thought to be based on ischemic condition; however, it has never been demonstrated. In this study, we examined the expression of ischemia-associated proteins in ischemic fasciitis by immunohistochemical and genetic methods. Specifically, this study aimed to reveal the expression of HIF-1α, MDM2, CDK4, p16, and gene amplification of MDM2 gene. Seven cases of ischemic fasciitis from among the soft-tissue tumors registered at our institution were retrieved. Histopathological findings were as follows: poorly demarcated nodular masses, a proliferation of spindle-shaped fibroblastic or myofibroblastic cells with oval nuclei and eosinophilic or pale cytoplasm, zonal fibrinous deposition, pseudocystic degeneration, granulation-like proliferation of capillary vessels, ganglion-like cells, myxoid or hyalinized stroma, and chronic inflammatory infiltration. Immunohistochemically, the spindle cells were positive for HIF-1α (7/7 cases), MDM2 (4/7 cases), CDK4 (4/7 cases), p16 (7/7 cases), p53 (2/7 case), cyclin D1 (7/7 cases), and alpha-smooth muscle actin (6/7 cases). Neither MDM2 gene amplification nor USP6 gene split signal was detected in any case. Overexpression of the above proteins may be associated with the pathogenic mechanism of ischemic fasciitis. It is noted that the immunohistochemical positivity of MDM2, CDK4, and p16 do not necessarily indicate malignant neoplasm such as dedifferentiated liposarcoma.
缺血性筋膜炎是一种良性肌成纤维细胞病变，发生于老年人或卧床患者的骶部或大腿近端。缺血性筋膜炎的发病机制被认为基于缺血状态；然而，这从未得到证实。在本研究中，我们通过免疫组织化学和基因方法检测了缺血性筋膜炎中缺血相关蛋白的表达。具体而言，本研究旨在揭示缺氧诱导因子-1α（HIF-1α）、鼠双微体2（MDM2）、细胞周期蛋白依赖性激酶4（CDK4）、p16以及MDM2基因扩增的表达情况。从我们机构登记的软组织肿瘤中检索出7例缺血性筋膜炎病例。组织病理学表现如下：边界不清的结节状肿块，梭形纤维母细胞或肌成纤维细胞增生，细胞核呈椭圆形，胞质嗜酸性或淡染，带状纤维蛋白沉积，假囊性变性，毛细血管呈肉芽样增生，神经节样细胞，黏液样或玻璃样变性的间质，以及慢性炎症浸润。免疫组织化学检测显示，梭形细胞HIF-1α阳性（7/7例）、MDM2阳性（4/7例）、CDK4阳性（4/7例）、p16阳性（7/7例）、p53阳性（2/7例）、细胞周期蛋白D1阳性（7/7例）、α-平滑肌肌动蛋白阳性（6/7例）。所有病例均未检测到MDM2基因扩增和泛素特异性蛋白酶6（USP6）基因断裂信号。上述蛋白的过表达可能与缺血性筋膜炎的发病机制有关。需要注意的是，MDM2、CDK4和p16的免疫组织化学阳性不一定表明存在去分化脂肪肉瘤等恶性肿瘤。
