肺原发淋巴上皮样癌18例临床病理研究

Clinicopathologic study of lung primary lymphoepithelial-like carcinoma: an analysis of 18 cases

目的探讨肺原发淋巴上皮样癌(lymphoepithelial-like carcinoma,LELC)的临床病理特点。方法选取2006年1月至2016年5月住院、经手术切除、病理诊断证实为肺原发LELC的18例患者的临床资料,所有患者均常规行鼻咽部检查未发现原发性鼻咽肿瘤。研究其临床特点、病理形态学特征、相关免疫组化及EB病毒编码的小RNA(EBER)原位杂交检测结果,并进行相关文献的复习。结果男性5例,女性13例;年龄39~69岁,中位年龄54岁。肉眼观肿物结节多为单发,类圆形,边界欠清,切面灰白灰褐色、实性质中;镜下瘤细胞极似鼻咽部泡状核细胞癌,呈大小不等片块状或巢状排列,癌细胞大,胞质中等量,淡染或弱嗜酸性,核呈泡状,核仁清晰,核分裂像可见,无鳞状细胞或腺样分化特征,纤维间质内见大量成熟的淋巴细胞、浆细胞浸润;免疫组化广谱细胞角蛋白(panCK)、CK5/6阳性率均为100%(18/18),p63阳性率均为94.4%(17/18),EBER原位杂交阳性率100%(18/18)。结论肺原发LELC属肺大细胞癌的一种少见的变异型肿瘤,临床表现无特异性,与EB病毒感染密切相关,诊断主要依靠病理组织形态学、免疫组织化学和原位杂交检测结果,EBER原位杂交阳性可作为有效诊断依据。

Objective To study the clinicopathologic features of primary lymphoepithelial-like carcinoma（LELC） of the lung. Methods Clinical data of 18 patients with lung primary LELC who were hospitalized between January 2006 and May 2016 and confirmed as LELC by surgical resection and pathological diagnosis were collected. Examination of nasopharynx was routinely performed in all patients, and no primary nasopharyngeal neoplasm was found. The clinical characteristics, pathomorphological features, the results of relevant immunohistochemical detection and in situ hybridization （ISH） detec- tion of Epstein-Barr virus encoded-small RNA （EBER） were studied. Review of relevant literature was carried out. Results There were 5 males and 13 females aged 39 to 69 years （median age ：54 years）. Naked eye view showed that neoplasm nodules mostly were solitary, quasi-circular, solid and medium texture;boundary was not clear; cut surface presented hoar- taupe. Microscopic observation showed that the tumor cell was very similar to that of nasopharyngeal vesicular nuclei cell carcinoma;the tumor cell presented size-unequal blocky or nest like arrangement;cancer cell was large ; cytoplasm had mo- derate quantity, pale or weakly eosinophilic in color;cell nucleus appeared bulliform; nucleolus was clear;mitotic figure of nucleus was visible;there were no features of squamous cells or glandular differentiation;the infiltrations of a large number of mature lymphocytes and plasma cells in fibrous stroma were found. The positive rates of pan-cytokeratin （panCK） and CK5/6 were all 100% （ 18/18 ）. The positive rate of p63 was 94.4% （ 17/18 ）. The positive rate of ISH of EBER was 100% （18/18）. Conclusions Lung primary LELC is a rare variant type tumor in lung large cell carcinoma. Clinical mani- festations of LELC were no specific. LELC was closely related to EB virus infection. The diagnosis of LELC mainly depends on the testing results of pathological tissue morphology, immunohistoehemistry and ISH. Positive ISH of EBER can be used as an effective diagnostic basis.