Chang Kenneth T E, Chadha Neil K, Leung Richard, Shago Mary, Phillips M James, Thorner Paul S
Department of Pediatric Laboratory Medicine, Hospital for Sick Children, Toronto, Ontario, Canada.
Pediatr Dev Pathol. 2010 Jul-Aug;13(4):331-7. doi: 10.2350/09-08-0701-CR.1.
Lymphadenoma of the salivary gland is a rare benign tumor with only 11 reported cases in the English language literature, most of which have occurred in adults. We report a case of a lymphadenoma occurring in the parotid gland of a 15-year-old girl. The tumor was composed of variably sized cystic cavities within abundant reactive lymphoid tissue. The cystic spaces were filled with eosinophilic secretions with occasional histiocytes. Many of these features were also apparent on cytologic preparations. The cysts were lined by epithelium lacking atypia and showed luminal and abluminal differentiation both by immunohistochemistry and by electron microscopy. Tumor cells were not cycling as determined by MIB1 immunostaining, and the tumor karyotype was normal. This is only the second case to be reported in the pediatric age group. Ultrastructural features and karyotype analysis are reported for the first time. Although this tumor is rarely encountered by pediatric pathologists, awareness of its existence is important to distinguish it from possible malignant mimics, such as lymphoepithelial carcinoma and metastatic mucoepidermoid carcinoma in a lymph node.
涎腺淋巴腺瘤是一种罕见的良性肿瘤，英文文献中仅报道过11例，其中大多数发生于成人。我们报告1例发生于一名15岁女孩腮腺的淋巴腺瘤。肿瘤由丰富的反应性淋巴组织内大小不一的囊腔构成。囊腔内充满嗜酸性分泌物，偶见组织细胞。这些特征在细胞涂片上也很明显。囊肿内衬无异型性的上皮，免疫组化和电镜检查均显示有腔内和腔外分化。MIB1免疫染色显示肿瘤细胞无增殖，肿瘤核型正常。这是儿科年龄组报道的第二例。首次报道了超微结构特征和核型分析。尽管儿科病理学家很少遇到这种肿瘤，但了解其存在对于将其与可能的恶性模仿物，如淋巴结中的淋巴上皮癌和转移性黏液表皮样癌相鉴别很重要。
