Friborg Jeppe, Hamilton-Therkildsen Marianne, Homoe Preben, Kristensen Claus, Hui Angela, Liu Fei-Fei, Weinreb Ilan
Department of Radiation Oncology, University Health Network, Toronto, ON, Canada.
Head Neck Pathol. 2012 Dec;6(4):445-50. doi: 10.1007/s12105-012-0394-z. Epub 2012 Aug 28.
Nasopharyngeal carcinomas of the undifferentiated or lymphoepithelial type are most commonly seen in South East Asians. Identical tumors have also been described at a variety of other sites including lung, skin and salivary gland and have been referred to by a number of names including lymphoepithelial carcinoma (LEC). LECs of major salivary gland are extremely rare. They are particularly common amongst the Inuit populations of the arctic region including Greenland (Denmark), Canada and Alaska, as well as South East Asians. Within the Inuit group, this tumor represents the majority of all salivary gland carcinomas. Amongst primary LEC of major salivary gland, most cases reported in the literature have represented typical nasopharynx-like tumors. Variants of Epstein-Barr Virus (EBV) associated LEC have not been described previously, to the best of our knowledge. In this report, we describe 4 EBV-associated major salivary gland LECs with prominent basaloid morphology, which represent 22 % of a cohort of 18 salivary LECs from an Inuit population in Greenland. The features described in these cases raise a differential diagnosis of other basaloid tumors, particularly in light of the salivary gland location. A basaloid variant of LEC in major salivary gland should be recognized, especially in highly prone populations, to avoid misdiagnosis of other more common salivary tumors.
未分化型或淋巴上皮样鼻咽癌在东南亚人群中最为常见。在包括肺、皮肤和唾液腺在内的其他多种部位也发现了类似的肿瘤,它们有许多名称,包括淋巴上皮癌(LEC)。大唾液腺的LEC极为罕见。它们在北极地区的因纽特人群中尤为常见,包括格陵兰(丹麦)、加拿大和阿拉斯加,以及东南亚人群。在因纽特人群中,这种肿瘤占所有唾液腺癌的大多数。在大唾液腺原发性LEC中,文献报道的大多数病例为典型的鼻咽样肿瘤。据我们所知,此前尚未描述过与爱泼斯坦-巴尔病毒(EBV)相关的LEC变体。在本报告中,我们描述了4例具有显著基底样形态的与EBV相关的大唾液腺LEC,占来自格陵兰因纽特人群的18例唾液腺LEC队列的22%。这些病例中描述的特征引发了对其他基底样肿瘤的鉴别诊断,特别是考虑到唾液腺的位置。应认识到大唾液腺LEC的基底样变体,尤其是在高发人群中,可以避免误诊为其他更常见的唾液腺肿瘤。