Wang Kuo-Hsien, Chu Jan-Show, Lin Yun-Ho, Hu Chung-Hong, Lee Woan-Ruoh
Department of Dermatology, Taipei Municipal Wan-Fang Hospital, Taipei, Taiwan.
J Cutan Pathol. 2004 Apr;31(4):336-40. doi: 10.1111/j.0303-6987.2004.0181.x.
Milium-like syringoma is a variant of syringoma first described in 1987. Only few cases have been reported in the literature. It may be misleading clinically, and its histogenesis has not been clarified.
We present a case of periorbital milium-like syringoma, with studies on the histopathologic, histochemical, and immunohistochemical features.
Histology showed a large keratin-filled cyst in the upper portion of the lesion approximating the epidermis. Serial sections revealed that the cyst connected with the underlying syringomatous epithelial strands. Melanin was absent in the wall of the cyst, as demonstrated by Fontana-Masson stain. Cytokeratin 7 was expressed neither in the milia nor in the solid epithelial parts. Carcinoembryonic antigen (CEA) reactivity was seen in the luminal cells of the keratinous cysts. However, in the largest keratin-filled cyst clinically suggesting a milium, only the lower half of the cyst was positive for CEA. These results proved that the milia were part of syringoma with eccrine duct differentiation. Fusion of the upper half of the largest cyst with the epidermis may explain the absence of CEA positivity in this part, analogous with eccrine duct milia. Review of the literature indicated that this variant of syringoma occurs more often in Asians.
We present evidence, and propose the histogenesis of milium-like syringoma, that it is a variant of syringoma with a prominent cystic component showing features of eccrine duct milia. Recognition of its nature is of therapeutic significance. Further studies are required to verify its clinical characteristics as compared with ordinary syringomas.
粟丘疹样汗管瘤是汗管瘤的一种变异型，于1987年首次被描述。文献中仅报道了少数病例。它在临床上可能具有误导性，其组织发生尚未明确。
我们报告一例眶周粟丘疹样汗管瘤病例，并对其组织病理学、组织化学和免疫组织化学特征进行了研究。
组织学显示病变上部靠近表皮处有一个大的充满角蛋白的囊肿。连续切片显示该囊肿与下方的汗管瘤样上皮条索相连。Fontana-Masson染色显示囊肿壁无黑色素。细胞角蛋白7在粟丘疹及实性上皮部分均未表达。在角质囊肿的管腔细胞中可见癌胚抗原（CEA）反应性。然而，在临床上提示为粟丘疹的最大的充满角蛋白的囊肿中，仅囊肿的下半部分CEA呈阳性。这些结果证明粟丘疹是具有小汗腺导管分化的汗管瘤的一部分。最大囊肿的上半部分与表皮融合可能解释了该部分CEA阳性缺失的原因，这与小汗腺导管粟丘疹类似。文献回顾表明，这种汗管瘤变异型在亚洲人中更常见。
我们提供了证据，并提出了粟丘疹样汗管瘤的组织发生，即它是汗管瘤的一种变异型，具有突出的囊性成分，表现出小汗腺导管粟丘疹的特征。认识其本质具有治疗意义。需要进一步研究以验证其与普通汗管瘤相比的临床特征。
