Johansson L, Lindén C J
Department of Pathology, University Hospital, Lund, Sweden.
Chest. 1996 Jan;109(1):109-14. doi: 10.1378/chest.109.1.109.
The prognosis of patients with pleural mesothelioma is more dependent on "pretreatment factors" than on the effect of therapeutic interventions. Histopathologic subtype is one of several important prognostic factors in pleural mesothelioma, and several studies indicate that the epithelial subtype of pleural mesotheliomas has a more favorable prognosis than the sarcomatoid. In this study, we retrospectively evaluated qualitative and quantitative aspects of the tissue specimens used for histopathologic diagnosis in 85 patients with pleural mesothelioma.
The prognostic roles of two different histopathologic classification systems were evaluated in 85 consecutive cases of pleural mesotheliomas. Efficiency of different diagnostic procedures, influence of the size of the biopsy specimens on the histopathologic diagnosis, and immunohistochemical profiles for histopathologic subtypes of mesotheliomas were also evaluated.
Patients with pure epithelial mesotheliomas (n = 35), and especially those with the tubulopapillary subtype (n = 18) of epithelial mesotheliomas, survived significantly longer than those with a sarcomatoid component (n = 50). With larger biopsy specimens (surgical biopsy, autopsy), more tumors were classified as biphasic (36/78 vs 9/44, p < 0.005). The sarcomatoid mesotheliomas comprised about 20% of the tumors regardless of type of biopsy. Staining intensity for cytokeratin CAM 5.2 was equal in all types of mesotheliomas, while intensity with cytokeratin AE1/AE3 decreased from the epithelial to the sarcomatoid mesotheliomas. Staining with vimentin was most intense among the sarcomatoid mesotheliomas, while with epithelial membrane antigen it was most intense among the epithelial mesotheliomas.
The quality of the biopsy specimens has considerable impact on the possibility to arrive at a correct histopathologic diagnosis. Based on our results, we suggest tubulopapillary mesotheliomas be regarded as "low-grade mesotheliomas" and other types, including the epithelioid type of epithelial mesotheliomas, as "high-grade mesotheliomas." This should be taken into account when designing clinical trials.
胸膜间皮瘤患者的预后更多地取决于“治疗前因素”，而非治疗干预的效果。组织病理学亚型是胸膜间皮瘤几个重要的预后因素之一，多项研究表明，胸膜间皮瘤的上皮亚型预后比肉瘤样亚型更有利。在本研究中，我们回顾性评估了85例胸膜间皮瘤患者用于组织病理学诊断的组织标本的定性和定量方面。
在85例连续的胸膜间皮瘤病例中评估了两种不同组织病理学分类系统的预后作用。还评估了不同诊断程序的效率、活检标本大小对组织病理学诊断的影响以及间皮瘤组织病理学亚型的免疫组化特征。
纯上皮性间皮瘤患者（n = 35），尤其是那些具有上皮性间皮瘤管状乳头亚型（n = 18）的患者，存活时间明显长于具有肉瘤样成分的患者（n = 50）。活检标本较大（手术活检、尸检）时，更多肿瘤被分类为双相性（36/78 vs 9/44，p < 0.005）。无论活检类型如何，肉瘤样间皮瘤约占肿瘤的20%。细胞角蛋白CAM 5.2的染色强度在所有类型的间皮瘤中相同，而细胞角蛋白AE1/AE3的强度从上皮性间皮瘤到肉瘤样间皮瘤逐渐降低。波形蛋白染色在肉瘤样间皮瘤中最强，而上皮膜抗原染色在上皮性间皮瘤中最强。
活检标本的质量对获得正确的组织病理学诊断的可能性有相当大的影响。根据我们的结果，我们建议将管状乳头间皮瘤视为“低级别间皮瘤”，将其他类型，包括上皮性间皮瘤的上皮样类型，视为“高级别间皮瘤”。在设计临床试验时应考虑到这一点。
