Morohashi M, Sakamoto F, Takenouchi T, Hashimoto T, Tago O, Ito M
Department of Dermatology, Niigata University School Medicine, Japan.
J Cutan Pathol. 2000 Apr;27(4):191-8. doi: 10.1034/j.1600-0560.2000.027004191.x.
We report the case of a 22-year-old woman with a nevoid plaque that we termed localized follicular hamartoma. The plaque was noticed at puberty on a unilateral site of the face and scalp. Clinically, it revealed numerous, skin-colored to light brown papules alone and in groups, occasionally bearing a single hair. Histologically, branched epithelial nests of squamoid and/or basaloid cells were revealed in connection with the interfollicular epidermis and the upper portions of hair follicles, of which the lower portions showed normal structures. Immunohistochemically, the epithelial nests showed the keratin expression consisted with that of the infundibular epithelium. S-100-positive cells were found in the epithelial nests and the stroma. Factor XIIIa-positive dendritic cells were numerous in adjacent to the epithelial nests. Ultrastructurally, immature melanocytes with a small number of premelanosomes and Merkel cells were found in the nests. Stromal dendritic cells showed the adherent features of the cytoplasmic processes to anchoring fibrils or basal lamina of the epithelial nests. From these findings, our case is a hamartoma, which seems to be an abortive growth of secondary hair germs with a limited differentiation to the upper follicular portion.
我们报告了一例22岁女性病例，其患有一个我们称为局限性毛囊错构瘤的痣样斑块。该斑块在青春期时于面部和头皮的单侧部位被发现。临床上，它表现为单独或成群的许多肤色至浅棕色丘疹，偶尔带有一根毛发。组织学上，可见与毛囊间表皮和毛囊上部相连的分支状鳞状和/或基底样上皮巢，其下部结构正常。免疫组化显示，上皮巢的角蛋白表达与漏斗状上皮一致。在上皮巢和基质中发现S-100阳性细胞。在紧邻上皮巢处有大量因子ⅩⅢa阳性树突状细胞。超微结构上，在上皮巢中发现了含有少量前黑素体的未成熟黑素细胞和默克尔细胞。基质树突状细胞显示其胞质突起与上皮巢的锚定纤维或基膜有黏附特征。基于这些发现，我们的病例是一种错构瘤，似乎是次级毛胚的发育不全性生长，仅向上部毛囊部分有有限的分化。
