Ordóñez N G
The University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
Am J Surg Pathol. 1998 Oct;22(10):1215-21. doi: 10.1097/00000478-199810000-00006.
The immunohistochemical diagnosis of mesothelioma is commonly made by using a battery of antibodies that reacts with lung adenocarcinomas but not with epithelial mesotheliomas. Only recently have markers that are often expressed in mesotheliomas but not in adenocarcinomas been recognized. Some of these markers, however, require frozen tissue sections, whereas others are not commercially available, or their value remains controversial. In a recent publication, it was suggested that immunostaining for cytokeratin 5/6 could assist in distinguishing epithelial mesothelioma from lung adenocarcinoma. To determine the practical value of cytokeratin 5/6 immunostaining in the diagnosis of mesothelioma, 40 formalin-fixed, paraffin-embedded epithelial pleural mesotheliomas, 30 pulmonary adenocarcinomas, 93 nonpulmonary adenocarcinomas, 15 squamous carcinomas of the lung, 5 large cell undifferentiated carcinomas of the lung, and 12 metastatic transitional cell carcinomas to the lung were stained with the same antibody, which was obtained from a commercial source. Cytokeratin 5/6 reactivity was observed in all 40 mesotheliomas, but there was none in any of the 30 pulmonary adenocarcinomas. Focal or weak reactivity was observed in 14 of 93 nonpulmonary adenocarcinomas (10 of 30 ovarian, 2 of 10 endometrial, 1 of 18 breast, I of 7 thyroid, 0 of 10 kidney, 0 of 10 colonic, and 0 of 8 prostatic). All 15 squamous carcinomas of the lung, 6 of 12 transitional cell carcinomas metastatic to the lung, and 3 of 5 large cell undifferentiated carcinomas of the lung expressed cytokeratin 5/6. It is concluded that cytokeratin 5/6 immunostaining is not only useful in separating epithelial pleural mesotheliomas from pulmonary adenocarcinomas but also can assist in distinguishing epithelial mesotheliomas from nonpulmonary adenocarcinomas metastatic to the pleura.
间皮瘤的免疫组化诊断通常通过使用一组与肺腺癌反应但不与上皮性间皮瘤反应的抗体来进行。直到最近，才认识到一些常在间皮瘤中表达而不在腺癌中表达的标志物。然而，其中一些标志物需要冷冻组织切片，而其他一些则没有商业供应，或者它们的价值仍存在争议。在最近的一篇出版物中，有人提出细胞角蛋白5/6免疫染色有助于区分上皮性间皮瘤和肺腺癌。为了确定细胞角蛋白5/6免疫染色在间皮瘤诊断中的实际价值，用从商业来源获得的同一抗体对40例福尔马林固定、石蜡包埋的上皮性胸膜间皮瘤、30例肺腺癌、93例非肺腺癌、15例肺鳞状细胞癌、5例肺大细胞未分化癌和12例肺转移性移行细胞癌进行染色。在所有40例间皮瘤中均观察到细胞角蛋白5/6反应性，但在30例肺腺癌中均未观察到。在93例非肺腺癌中有14例（30例卵巢癌中的10例、10例子宫内膜癌中的2例、18例乳腺癌中的1例、7例甲状腺癌中的1例、10例肾癌中的0例、10例结肠癌中的0例和8例前列腺癌中的0例）观察到局灶性或弱阳性反应。所有15例肺鳞状细胞癌、12例肺转移性移行细胞癌中的6例以及5例肺大细胞未分化癌中的3例均表达细胞角蛋白5/6。结论是，细胞角蛋白5/6免疫染色不仅有助于将上皮性胸膜间皮瘤与肺腺癌区分开来，而且还可以协助将上皮性间皮瘤与转移至胸膜的非肺腺癌区分开来。
