Department of Pathology, Ningbo Diagnostic Pathology Center, Huan Cheng Bei Lu, Jiang Bei District, Ningbo, 315000, Zhejiang, China.
Virchows Arch. 2021 Aug;479(2):257-263. doi: 10.1007/s00428-021-03048-y. Epub 2021 Feb 11.
Sarcomatoid malignant mesothelioma (SMM) tends to occur in the pleura and is morphologically similar to lung sarcomatoid carcinoma (LSC) and organizing pleuritis (OP). Because SMM often does not express mesothelial markers, it is very difficult to distinguish from LSC and OP. GATA-binding protein 3 (GATA3) is a specific immunohistochemical (IHC) marker of breast and urothelial carcinoma. We routinely find that GATA is expressed in MM; however, GATA3 expression in SMM and its reference value for distinguishing SMM from LSC and OP remain unclear. Here, we used IHC methods to detect the expression of GATA3 and classic mesothelial markers in 17 SMM, 12 LSC, and 7 OP cases. We detected the following expression rates in SMM versus LSC cases: GATA3 (70.6% vs. 16.7%, p = 0.008), calretinin (52.9% vs. 8.3%, p = 0.019), Wilms tumor (WT)-1 (64.7% vs. 0%, p = 0.000), D2-40 (47.1% vs. 16.7%, p = 0.126), CK5/6 (35.3% vs. 25.0%, p = 0.694), and pan-cytokeratin (CKpan) (88.2% vs. 100.0%, p = 0.498). The specificities of calretinin, WT-1, and GATA3 in distinguishing SMM from LSC were 91.7%, 100%, and 83.3%, respectively, and combinations of any two of these three markers exhibited 100% specificity for SMM. Notably, the sensitivity of calretinin+/WT1+ staining for SMM was only 23.5%, which increased to 64.7% after including GATA3. Furthermore, all OP cases showed partial or diffuse expression of CKpan, WT-1, and D2-40 but no GATA3 and calretinin expression. In conclusion, GATA3 is an IHC marker with excellent sensitivity and specificity for SMM, and the combined consideration of GATA3, calretinin, and WT-1 was best for distinguishing SMM from LSC. Moreover, CKpan, WT-1, and D2-40 had no value for distinguishing SMM from OP, and GATA3 and calretinin were the most specific markers for distinguishing these two lesions.
肉瘤样恶性间皮瘤（SMM）倾向于发生在胸膜，形态上类似于肺肉瘤样癌（LSC）和机化性胸膜炎（OP）。由于 SMM 通常不表达间皮标志物，因此很难将其与 LSC 和 OP 区分开来。GATA 结合蛋白 3（GATA3）是乳腺和尿路上皮癌的一种特定免疫组织化学（IHC）标志物。我们经常发现 GATA 在 MM 中表达；然而，SMM 中 GATA3 的表达及其用于区分 SMM 与 LSC 和 OP 的参考价值尚不清楚。在这里，我们使用 IHC 方法检测了 17 例 SMM、12 例 LSC 和 7 例 OP 病例中 GATA3 和经典间皮标志物的表达。我们在 SMM 与 LSC 病例中检测到以下表达率：GATA3（70.6% vs. 16.7%，p=0.008）、钙视网膜蛋白（52.9% vs. 8.3%，p=0.019）、Wilms 肿瘤（WT）-1（64.7% vs. 0%，p=0.000）、D2-40（47.1% vs. 16.7%，p=0.126）、CK5/6（35.3% vs. 25.0%，p=0.694）和 pan-cytokeratin（CKpan）（88.2% vs. 100.0%，p=0.498）。钙视网膜蛋白、WT-1 和 GATA3 在区分 SMM 与 LSC 方面的特异性分别为 91.7%、100%和 83.3%，这三种标志物中的任意两种组合在区分 SMM 方面均具有 100%的特异性。值得注意的是，钙视网膜蛋白+/WT1+染色对 SMM 的敏感性仅为 23.5%，而包含 GATA3 后则增加到 64.7%。此外，所有 OP 病例均表现为 CKpan、WT-1 和 D2-40 的部分或弥漫表达，但无 GATA3 和钙视网膜蛋白表达。总之，GATA3 是一种用于 SMM 的具有优异敏感性和特异性的 IHC 标志物，考虑 GATA3、钙视网膜蛋白和 WT-1 的联合使用最有利于区分 SMM 与 LSC。此外，CKpan、WT-1 和 D2-40 对区分 SMM 与 OP 没有价值，而 GATA3 和钙视网膜蛋白是区分这两种病变的最特异标志物。
