Department of Anatomical Pathology, Flinders University and Medical Centre, Adelaide, Australia.
Mod Pathol. 2010 Mar;23(3):470-9. doi: 10.1038/modpathol.2009.180. Epub 2010 Jan 15.
Sarcomatoid mesothelioma is the least common, but most aggressive of the three major histological types of mesotheliomas. This study comprises 326 cases of sarcomatoid mesotheliomas among 2000 consecutive malignant mesothelioma cases received in consultation (16%). Patients included 312 men (96%) and 14 women (4%), with a median age of 70 years (range 41-94 years). Most tumors were pleural (319; 98%), and 7 were peritoneal (2%). Some desmoplastic features were identified in 110 cases (34%), and 70 (21%) were classified as desmoplastic. Rare subtypes included two cases with a lymphohistiocytoid pattern (<1%) and eight heterologous mesotheliomas (2%). Labeling for cytokeratins (CKs) was observed in 261/280 cases (93%), and for calretinin and vimentin in 31 and 91%, respectively. Pleural plaques were present in 79% of cases for which information was available, and asbestosis was diagnosed in 34/127 cases (27%). Median survival was 3.5 months. Fiber analysis was performed in 61 cases. The median asbestos body count was 1640/g wet lung tissue (by light microscopy). Amosite fibers were the most commonly identified fibers using energy-dispersive X-ray analysis and were significantly higher in the sarcomatoid cases, as were uncoated fibers using scanning electron microscopy. This study represents the largest series of sarcomatoid and desmoplastic malignant mesotheliomas to date and confirms the diagnostic usefulness of CK immunohistochemistry. The relationship with asbestos exposure--particularly amosite--and an association with pleural plaques and less often asbestosis is confirmed.
肉瘤样间皮瘤是三种主要组织学类型的间皮瘤中最不常见但侵袭性最强的一种。这项研究包括在 2000 例连续会诊的恶性间皮瘤病例中，肉瘤样间皮瘤 326 例（16%）。患者包括 312 名男性（96%）和 14 名女性（4%），中位年龄为 70 岁（范围为 41-94 岁）。大多数肿瘤为胸膜（319 例，98%），7 例为腹膜（2%）。110 例（34%）存在一定程度的纤维组织增生特征，70 例（21%）被归类为纤维组织增生型。罕见的亚型包括 2 例具有淋巴组织细胞样形态（<1%）和 8 例异源性间皮瘤（2%）。280 例中有 261 例（93%）观察到细胞角蛋白（CKs）的标记，31 例（11%）和 91 例（32%）分别观察到钙视网膜蛋白和波形蛋白的标记。有信息可查的 79%的病例存在胸膜斑，34/127 例（27%）诊断为石棉肺。中位生存期为 3.5 个月。在 61 例中进行了纤维分析。通过光镜观察，每克湿肺组织中的石棉体计数中位数为 1640 个。用能量色散 X 射线分析，最常见的纤维是铁石棉纤维，在肉瘤样病例中含量明显更高，用扫描电子显微镜观察，未涂层纤维的含量也更高。本研究是迄今为止最大的一组肉瘤样和纤维组织增生性恶性间皮瘤系列，证实了 CK 免疫组化的诊断价值。间皮瘤与石棉暴露的关系——特别是铁石棉——与胸膜斑的关系以及与石棉肺的关系较少得到证实。
