A clinicopathological study on diagnostic techniques for malignant mesothelioma in dogs and cats

间皮瘤是一种起源于体腔浆膜表面的恶性上皮性肿瘤，近年来发病率呈上升趋势。由于浆膜表面是来自内脏器官的各种恶性肿瘤（包括肺和乳腺腺癌）转移扩散的常见部位，因此将恶性间皮瘤与此类腺癌分离可能是一个重大挑战。免疫组化已被证明是有价值的恶性间皮瘤的诊断，虽然没有特异性抗体尚未开发，可以被接受为这些肿瘤的专属。为探讨免疫组化在间皮瘤诊断中的价值，对7例间皮瘤、6例滑膜肉瘤（SS）、5例肺腺癌（LA）和14例乳腺腺癌（MA）的手术和尸检标本进行免疫组化评价。应用广谱单克隆抗体：波形蛋白、钙视网膜蛋白、血栓调节蛋白、细胞角蛋白5/6、EMA、CEA、Ber-EP 4和MOC-31。这些抗体包括通常预期与间皮瘤反应的标记物（“阳性”标记物）和通常预期不与间皮瘤反应的标记物（“阴性”标记物）。波形蛋白在100%的间皮瘤、100%的SS、0%的LA和57.1%的MA中呈阳性。钙视黄蛋白仅在7.1%的MA中;细胞角蛋白5/6在100%的间皮瘤、33.3%的SS、100%的LA和100%的MA中; EMA在14.3%的间皮瘤、83.3%的SS、100%的LA和85.7%的MA中。血栓调节蛋白、CEA、Ber-EP 4和Moc-31在本研究中检查的所有肿瘤中均为阴性。我们的研究结果表明，波形蛋白和细胞角蛋白5/6的组合作为阳性标记物，EMA作为阴性标记物的显着有用性。三抗体免疫组化法检测的敏感性为85.7%，特异性为100%。

Mesothelioma is a malignant epithelial tumor originating from the serosal surface of body cavities and its incidence has increased in recent years. Because serosal surfaces are a common site of metastatic spread for a variety of malignant tumors from internal organs, including lung and mammary adenocarcinomas, the separation of malignant mesothelioma from such adenocarcinomas can be a major challenge. Immunohistochemistry has proven valuable for the diagnosis of malignant mesothlioma, although no specific antibodies have yet been developed that can be accepted as exclusive for these tumors. The purpose of this study was to evaluate the value of immunochemistry in the accurate diagnosis of mesothelioma.Surgical and necropsy specimens from 7 cases of mesothelioma, 6 cases of synovial sarcoma (SS), 5 cases of lung adenocarcinoma (LA), and 14 cases of mammary adenocarcinoma (MA) were evakuated immunohistochemically. A broad spectrum monoclonal antibodies was applied: vimentin, calretinin, thrombomodulin, cytokeratin 5/6, EMA, CEA, Ber-EP4, and MOC-31. These antibodies included markers that are commonly expected to react with mesothelioma ("positive" markers and markers that are not commonly expected to react with mesothelioma ("negative" markers).Vimentin was positive in 100% of mesothelioma, 100% of SS, 0% of LA, and 57.1% of MA.; Calretinin only in 7.1% of MA ; cytokeratin 5/6 in 100% of mesothlioma, 33.3% of SS, 100% of LA, and 100% of MA; and EMA in 14.3% of mesothelioma, 83.3% of SS, 100% of LA, and 85.7% of MA. Thrombomodulin, CEA, Ber-EP4, and Moc-31 were negative in all tumors examined in the present study. Our results demonstrate that the significant usefulness of a combination of vimentin and cytokeratin 5/6 as positive markers, and of EMA as a negative marker. The 3-antibody immunohistochemical panel showed the sensitivity of 85.7% and the specificity of 100%.