Wang Cai-Xia, Liu Biao, Wang Yan-Fen, Zhang Ru-Song, Yu Bo, Lu Zhen-Feng, Shi Qun-Li, Zhou Xiao-Jun
Department of Pathology, Clinical School of Medical College of Nanjing University, Nanjing Jingling Hospital Nanjing, China.
Int J Clin Exp Pathol. 2014 Feb 15;7(3):1266-74. eCollection 2014.
Pulmonary enteric adenocarcinoma (PEAC), a extremely rare variant of primary invasive adenocarcinoma of the lung, was recognized by the international multidisciplinary classification of lung adenocarcinoma which was proposed by the International Association for the Study of Lung Cancer (IASLC), the American Thoracic Society (ATS), and the European Respiratory Society (ERS) published in early 2011. Histologically, PEAC is considered to be mainly composed of tall columnar cells arranged in an irregular glandular cavity or cribriform pattern with extensive central necrosis which show high resemblance to that of intestinal epithelia and colorectal carcinomas. Immunohistochemically, PEAC can not only expresses typical proteins common to lung primaries but is positive for at least one intestinal markers, such as CDX2, cytokeratin (CK) 20, MUC2, therefore, the differentiation of primary PEACs from metastatic colorectal cancers can be challenging. In this study, we report 9 cases of PEAC and a panel of immunohistochemical protein markers of CK7, CK20, thyroid transcription factor 1 (TTF-1), Napsin A, MUC2 and villin was analyzed with the comparison of 20 metastatic colorectal carcinomas (MCRs), and 20 typical primary adenocarcinomas (tPACs). As was expected, CK7 expression was documented in all 9 PEACs and 20 tPCAs while CK20 was significantly more prevalent in adenocarcinoma that originated from colorectal. Additionally, we evaluate the classical mutations of EGFR, KRAS in the 9 cases of PEACs, it turned out that all tumors were EGFR-wild and KRAS-wild types, which confirmed that PEAC has a separate phenotype from usual pulmonary adenocarcinoma.
肺肠型腺癌（PEAC）是原发性肺浸润性腺癌中一种极其罕见的变异类型，它是由国际肺癌研究协会（IASLC）、美国胸科学会（ATS）和欧洲呼吸学会（ERS）于2011年初提出的国际多学科肺腺癌分类所认可的。从组织学上看，PEAC被认为主要由高柱状细胞组成，这些细胞排列在不规则的腺腔或筛状模式中，并伴有广泛的中央坏死，这与肠上皮和结直肠癌的表现高度相似。免疫组化方面，PEAC不仅表达肺原发性肿瘤常见的典型蛋白，而且至少对一种肠道标志物呈阳性，如CDX2、细胞角蛋白（CK）20、MUC2，因此，将原发性PEAC与转移性结直肠癌区分开来可能具有挑战性。在本研究中，我们报告了9例PEAC病例，并分析了一组免疫组化蛋白标志物，包括CK7、CK20、甲状腺转录因子1（TTF-1）、Napsin A、MUC2和绒毛蛋白，并与20例转移性结直肠癌（MCR）和20例典型原发性腺癌（tPAC）进行了比较。正如预期的那样，所有9例PEAC和20例tPCA中均检测到CK7表达，而CK20在源自结肠的腺癌中明显更为普遍。此外，我们评估了9例PEAC病例中EGFR、KRAS的经典突变情况，结果发现所有肿瘤均为EGFR野生型和KRAS野生型，这证实了PEAC具有与常见肺腺癌不同的表型。
