Tanaka Makoto, Sawamoto Osamu
Research Promotion Laboratory, Research and Development Center, Otsuka Pharmaceutical Factory, Inc., 115 Kuguhara, Tateiwa, Muya-cho, Naruto, Tokushima 772-8601, Japan.
J Toxicol Pathol. 2013 Sep;26(3):325-8. doi: 10.1293/tox.26.325. Epub 2013 Oct 15.
A spontaneous ameloblastic fibroma was found in a 9-week-old guinea pig. Histopathologically, neoplastic cells consisted of two components: an odontogenic epithelium and odontogenic mesenchyme. The odontogenic epithelium formed strands, nests and islands that were interspersed within the odontogenic mesenchyme. In the marginal region, odontoblasts and scant dysplastic eosinophilic material were seen between these two components. Immunohistochemically, the odontogenic epithelium was positive for cytokeratin AE1/AE3, and the odontogenic mesenchyme and odontoblast were positive for vimentin, in the same manner as in the normal tooth germ (control). We could not obtain conclusive data suggesting that the eosinophilic material was dental hard tissue because the eosinophilic material was not stained specifically by any methods. Based on these histological characteristics, the tumor in the present case was diagnosed as an ameloblastic fibroma. This is the first report of ameloblastic fibroma in guinea pigs.
在一只9周龄的豚鼠身上发现了一例自发性成釉细胞纤维瘤。组织病理学检查显示，肿瘤细胞由两种成分组成：牙源性上皮和牙源性间充质。牙源性上皮形成条索、巢状和岛状结构，散布于牙源性间充质内。在边缘区域，这两种成分之间可见成牙本质细胞和少量发育异常的嗜酸性物质。免疫组织化学检测显示，牙源性上皮细胞角蛋白AE1/AE3呈阳性，牙源性间充质和成牙本质细胞波形蛋白呈阳性，与正常牙胚（对照）情况相同。由于嗜酸性物质未被任何方法特异性染色，我们无法获得确凿数据表明该嗜酸性物质为牙硬组织。基于这些组织学特征，本病例中的肿瘤被诊断为成釉细胞纤维瘤。这是关于豚鼠成釉细胞纤维瘤的首次报道。
