鼻咽原发性腺样囊性癌及其与EB病毒感染的关系

Primary adenoid cystic carcinoma of the nasopharynx and its relation to Epstein-Barr virus infection

目的 探讨鼻咽癌高发的广州地区鼻咽原发性腺样囊性癌的临床病理特征及其与EB病毒感染的关系。方法 对17例鼻咽原发性腺样囊性癌进行临床资料分析。除HE、阿辛蓝及过碘酸Schiff(PAS)常规染色外,采用标记链酶素卵白素生物素(LUAB)免疫组织化学法检测一系列上皮性标志物、CD21和EB病毒编码的潜伏膜蛋白(LMP)1的表达。采用原位杂交法检测EB病毒编码的小RNAs(EBER)。用巢式聚合酶链反应(PCR)法检测EB病毒DNA W片段。结果 17例鼻咽原发性腺样囊性癌患者的男女之比为7:10,年龄30～63岁,中位年龄46岁。17例中14例的肿物呈明显局部侵袭性生长,病变属T3或T4期,仅1例有同侧颈淋巴结转移。大部分肿瘤细胞呈基底细胞样,核小而深染、仅有少许胞质;细胞之间常可见伊红染色同质性或黏液样物质;16例可见筛孔状的特征性结构。鼻咽原发性腺样囊性癌均表达广谱细胞角蛋白和上皮膜抗原。9例(9/17)可见少数癌细胞呈EBER阳性,采用巢式PCR法同时检测到这9例活检组织192bp的EB病毒W片段阳性带,EBER阳性癌细胞的病例中,5例的癌细胞表达LMP1;其中3例的肿瘤间质中又可见少数EBER阳性的浸润性淋巴细胞。所有17例的癌细胞,包括EBER阳性的癌细胞均不表达CD21。结论 鼻咽原发性腺样囊性癌患者以女性为多见。肿瘤生长呈明显的侵袭性。

Objective To investigate the clinicopathologic characteristics of primary nasopharyngeal adenoid cystic carcinoma ( NPACC) and its relation to Epstein-Barr virus ( EBV) infection in Guangzhou where is a high-incidence area of EBV-associated nasopharyngeal carcinoma ( NPC). Methods 17 cases of NPACC with clinical record and biopsy samples were collected in Guangzhou and their clinical manifestations were reviewed. Besides HE, Alcian blue and PAS, LSAB immunohistochemistry was performed for detecting the expression of a variety of epithelial markers, CD21 and EBV encoded LMP1. EBV encoded early RNAs (EBER) was detected by using in-situ hybridization. Nested PCR was applied for studying the presence of EBV W-fragment in tissues. Results The ratio of male to female was 7:10. The patients' age ranged from 30 to 63 years, and the median age was 46 years. 14 out of 17 tumors showed markedly local aggressive growth, presenting as T3 or T4. However, only 1 patient had metastasis of an ipsilateral cervical lymph node. The majority of neoplastic cells were basal-cell like in shape and with scanty cytoplasm and a deeply stained nucleus. Intercellular hyaline or mucinous substance was always present in between the carcinoma cells. Cribriform structure formed by the neoplastic cells could be found in 16 out of these 17 biopsies. The NPACC always express the wide-spectrum cytokeratin and the epithelium membrane antigen. Only a few or a small number of carcinoma cells showed nuclear EBER-signals in 9 cases (9/17). Concurrently, these 9 NPACCs showed a 192 bp W-fragment positive band on electrophoresis gel by nested PCR. LMP1 expression had been found in 5 out of the 9 NPACCs (55.6 % ) accompanying with EBER-positive carcinoma cells. The EBER-positive infiltrating lymphocytes could also be found in the stroma of 3 out of the 9 EBER-stained NPACC slides. All the tumor cells, including the EBER-positive cell of the 17 NPACCs showed no CD21 expression. Conclusions The female is predominant over the male in development of NPACC, which often accompanied with a markedly invasive capacity at the nasopharynx and its neighboring sites. Only a small number of tumor cells, nearly a half of the studied cases were infected with EBV. Therefore, it's postulated that there seems no close relation present between NPACC and EBV infection.