原发性肺淋巴上皮瘤样癌20例临床病理分析

Primary pulmonary lymphoepithelioma-like carcinoma: a clinicopathological analysis of twenty cases

目的探讨原发性肺淋巴上皮瘤样癌(lymphoepithelioma-like carcinoma,LELC)的临床病理特点、治疗及预后。方法回顾性分析20例原发性肺LELC的临床资料、病理形态、免疫表型、治疗等,并复习相关文献。结果镜下癌细胞呈合体样、巢片状排列生长;细胞核大、空泡状,核仁明显,细胞异型较大,间质内具有丰富的淋巴细胞浸润,类似鼻咽未分化癌的形态。免疫表型:癌细胞CKpan(20/20)、EBER(20/20)、CK5/6(19/20)、p63(18/20)及p40(16/20)均阳性。3例行EGFR基因突变检测阴性,2例行EML4-ALK融合基因检测阴性,1例行K-RAS基因突变检测阴性。治疗以手术、放化疗等综合治疗为主。结论原发性肺LELC是肺部少见的恶性肿瘤,组织形态及免疫组化是诊断的主要手段,但要排除其他部位转移;同时EGFR、ALK等肺癌常见基因突变在肺LELC中少见,PD1/PD-L1突变可能有一定的潜在治疗价值。目前,临床仍以经验性治疗为主。

Purpose To study the elinieopathological char- acteristics, treatments and prognosis of primary pulmonary lym- phoepithelioma-like carcinoma （LELC）. Methods Twenty ca- ses of LELC were collected and the elinicopathologieal character- istics, immunohistochemical expression, survival data and clini- cal treatments were analyzed, with review of the literatures. Re- suits Histopathologically, it was characterized by the syneytial pattern of growing with large vesicular nuclei, conspicuous nu- eleoli, and a marked lymphocytic infiltrate in the stroma that was similar to undifferentiated nasopharyngeal carcinoma. The immu- nohistochemical staining of CKpan showed positive expression in all cases （ 100% ）. Also the positive expression of in situ hy- bridization of Epstein-Bar virus-encoded RNA （EBER） were in all cases （ 100% ） while the positive cases of CK5/6, p63 and 1340 were 19, 18, and 16 respectively. But gene mutations suchas EGFR, K-RAS were negative. All the LELC patients in this cohort were survived until the deadline of follow-up. Comprehen- sive treatments were done such as surgical resection, radiothera- py and chemotherapy. Conclusion Primary pulmonary LELC is a rare disease that histomorphological analysis and immunohisto- chemistry are the main methods of diagnosis for it. It must be excluded the metastasis carcinoma from other locations. While both EGFR mutation and anaplastic lymphoma kinase （ALK） mutation could be commonly detected in non-small cell lung cancer, but seldom in LELC of lung. The high expression of PD1/PD-L1 may provide a rationale for immunotherapy in this subtype of lung cancer. Currently, experimental therapy is still taken in the pulmonary LELC.