Department of Pathology, Vancouver General Hospital and University of British Columbia, Vancouver, BC, Canada.
Department of Pathology, Fukuoka University School of Medicine and Hospital, Fukuoka, Japan.
Lung Cancer. 2018 Oct;124:95-101. doi: 10.1016/j.lungcan.2018.07.041. Epub 2018 Jul 30.
The separation of benign from malignant mesothelial proliferations and exact subclassification of mesothelioma subtypes is crucial to determining patient care and prognosis but morphologically can be very difficult.
This session of the 2018 IMIG meeting addressed these problems.
A new immunohistochemical marker, methylthioadenosine phosphorylase, was shown to correlate well with CDKN2A FISH and is cheaper and faster to run. A 117 gene expression panel also provided good separation on both tissue biopsy and cytology samples. Review of a series of mesotheliomas thought to be biphasic produced only a moderate level of agreement among expert pathologists with some cases being classified as purely epithelioid or sarcomatoid; these classifications had prognostic significance. The entity called transitional mesothelioma was found to behave exactly like sarcomatoid mesothelioma. RNA-seq analysis of a large series of mesotheliomas from a public database showed that, genetically, the morphologic breakdown into epithelioid, sarcomatoid, or biphasic mesotheliomas is artificial because there is a continuous spectrum of genomic changes. There are now criteria for the diagnosis of mesothelioma in situ and this is potentially important, since such cases might be curable.
This session documented new morphological and molecular approaches to separating benign from malignant mesothelial proliferations and to subclassifying malignant mesoteheliomas in clinical relevant ways.
良性间皮增生与恶性间皮瘤的区分，以及间皮瘤亚型的准确分类，对于确定患者的治疗和预后至关重要，但在形态学上可能非常困难。
2018 年国际间皮瘤学会会议的这一环节解决了这些问题。
一种新的免疫组织化学标志物——甲基硫腺苷磷酸化酶，与 CDKN2A FISH 相关性良好，且成本更低、运行速度更快。一个 117 个基因表达谱也能很好地区分组织活检和细胞学样本。对一系列被认为是双相性的间皮瘤进行的回顾性研究，仅在专家病理学家中产生了中等程度的一致性，有些病例被归类为纯上皮样或肉瘤样；这些分类具有预后意义。被称为过渡型间皮瘤的实体被发现与肉瘤样间皮瘤的行为完全一致。从公共数据库中对大量间皮瘤进行 RNA-seq 分析表明，从遗传学角度来看，将形态学分为上皮样、肉瘤样或双相性间皮瘤是人为的，因为存在连续的基因组变化谱。现在已经有了原位间皮瘤的诊断标准，这是非常重要的，因为这类病例可能是可以治愈的。
本环节记录了新的形态学和分子方法，用于区分良性和恶性间皮增生，以及以临床相关的方式对恶性间皮瘤进行亚分类。
