Abstract：
UNASSIGNED: An 87-year-old woman presented with a pedunculated nodule of 1.2 × 1.2 × 0.6 cm on her left cheek. Microscopic examination of the lesion revealed bowenoid and rosette-like basaloid components, resembling Bowen disease and neuroendocrine carcinoma, respectively. Immunohistochemically, both components were positive for Wnt signaling pathway molecules-nuclear/cytoplasmic beta-catenin, lymphoid enhancer binding factor 1 (LEF1), and caudal type homeobox 2 (CDX2)-and the adnexal marker SRY-box transcription factor 9 (SOX9). Unlike neuroendocrine tumors and basal cell carcinomas, the basaloid component in the present case was negative for chromogranin A, INSM1, synaptophysin, and p40. Previously reported cases of similar CDX2-positive lesions were diagnosed as squamous cell carcinoma with enteric adenocarcinomatous differentiation and basaloid cutaneous carcinoma with a primitive cytomorphology. However, the lesion in the present case was simultaneously positive for SOX9, indicating adnexal differentiation. In particular, the expression of multiple Wnt signaling pathway molecules indicates follicular differentiation despite the absence of morphological follicular features, such as shadow cells. Moreover, shared immunopositivity for SOX9, CDX2, nuclear/cytoplasmic beta-catenin, and LEF1 by both bowenoid and basaloid components indicated that the bowenoid component did not represent Bowen disease but a part of the adnexal tumor, and that the basaloid component was not a tumor-to-tumor metastasis. After complete excision, no recurrence has been observed for 5 months. The findings of the present case expand the histological spectrum of cutaneous adnexal tumors with follicular immunophenotypic differentiation.
摘要：
■一名87岁的妇女，其左脸颊上有一个1.2×1.2×0.6厘米的带蒂结节。病变的显微镜检查显示弓形体和玫瑰花状基底细胞样成分，类似于Bowen病和神经内分泌癌，分别。免疫组织化学，这两个成分对Wnt信号通路分子-核/细胞质β-catenin均呈阳性，淋巴增强子结合因子1（LEF1），和尾型同源异型盒2（CDX2）-和附件标记SRY-盒转录因子9（SOX9）。与神经内分泌肿瘤和基底细胞癌不同，本病例中的基底细胞成分对嗜铬粒蛋白A呈阴性，INSM1，突触素，p40先前报道的类似CDX2阳性病变的病例被诊断为具有肠腺癌分化的鳞状细胞癌和具有原始细胞形态的基底样皮肤癌。然而,本病例的病变同时SOX9阳性,提示附件分化.特别是,多个Wnt信号通路分子的表达表明卵泡分化，尽管没有形态卵泡特征，如阴影细胞。此外，SOX9，CDX2，核/细胞质β-连环蛋白，和LEF1的弓形体和基底样成分表明弓形体成分不代表Bowen病，而是附件肿瘤的一部分，并且基底细胞成分不是肿瘤到肿瘤的转移。完全切除后,5个月内无复发.本病例的发现扩大了具有滤泡免疫表型分化的皮肤附件肿瘤的组织学范围。
