Abstract

Background: Mammary analogue secretory carcinoma (MASC) is characterized by similar histologic, immunohistochemical, and molecular features with breast secretory carcinoma. MASC usually occurs in adults. Case report: A 4-year-old boy presented with a right infra-auricular mass. Features of the tumor include solid, tubular, and papillary growth patterns, with homogenous eosinophilic secretions inside microcystic structures. Immunohistochemical stains showed strong, diffuse staining for CK7, S100, pan-TRK protein. P63 was positive in a peripheral pattern. Fluorescence in situ hybridization (FISH) analysis showed the characteristic ETV6-NTRK3 gene fusion. Conclusion: Typical histological, immunohistochemical, and molecular features are present in MASC occurring early in childhood.

摘要

背景：类似乳腺分泌性癌 (MASC) 具有与乳腺分泌性癌相似的组织学、免疫组织化学和分子特征。MASC 通常发生在成人身上。病例报告：一名 4 岁男孩因右侧耳下肿块就诊。肿瘤的特征包括实性、管状和乳头状生长模式，微囊结构内有均质嗜酸性分泌物。免疫组织化学染色显示 CK7、S100、pan-TRK 蛋白呈强弥漫性染色。P63 在外围模式中呈阳性。荧光原位杂交 (FISH) 分析显示特征性的 ETV6-NTRK3 基因融合。结论：典型的组织学、免疫组织化学和分子特征存在于儿童早期发生的 MASC 中。