Takeda Y, Satoh M, Nakamura S, Matsumoto D
Department of Oral Pathology, School of Dentistry, Iwate Medical University, Morioka, Japan.
Pathol Int. 2000 Dec;50(12):999-1002. doi: 10.1046/j.1440-1827.2000.01141.x.
The histologic and immunohistochemical findings of an extremely rare case of congenital soft tissue mass on the alveolar ridge in an infant are reported. The lesion clinically mimicked an ordinary congenital epulis (congenital granular cell epulis, granular cell tumor of the newborn); however, histologically it consisted of a conglomerate of spindle-shaped cells, akin to smooth muscle cells, which formed interlacing and whorled fasciculi. Nerve fibers with myxoid degeneration, capillaries and muscle walled small vessels intermingled with fasciculi of spindle-shaped cells. The border between the conglomerate of spindle-shaped cells and the surrounding connective tissue was not evident. Immunohistochemically, most of the spindle-shaped cells were intensely positive for antibodies to alpha-smooth muscle actin, HHF-35 and desmin. These findings suggest that the lesion was composed of mature smooth muscle cells that were of hamartomatous or choristomatous nature. The term 'congenital leiomyomatous epulis' is proposed.
报告了1例极其罕见的婴儿牙槽嵴先天性软组织肿块的组织学和免疫组化结果。该病变临床症状类似普通先天性龈瘤（先天性颗粒细胞龈瘤、新生儿颗粒细胞瘤）；然而，组织学上它由一团梭形细胞组成，类似于平滑肌细胞，形成交错和漩涡状束状结构。伴有黏液样变性的神经纤维、毛细血管和肌壁小血管与梭形细胞束相互交织。梭形细胞团与周围结缔组织之间的边界不明显。免疫组化显示，大多数梭形细胞对α-平滑肌肌动蛋白、HHF-35和结蛋白抗体呈强阳性。这些结果表明，该病变由错构瘤性或迷离瘤性的成熟平滑肌细胞组成。本文提出了“先天性平滑肌瘤性龈瘤”这一术语。
