Gao Ling, Reeves Ward, Demay Richard M
Department of Pathology, Division of Cytopathology, The University of Chicago, 5841 S. Maryland Avenue, Chicago, 60637, IL, USA.
Cytojournal. 2012;9:18. doi: 10.4103/1742-6413.99170. Epub 2012 Jul 28.
Malignant mesothelioma (MM) is an aggressive neoplasm with a poor prognosis. Its incidence has been increasing worldwide. Cytological examination of an effusion is often the first opportunity to diagnose MM. However, the cytological diagnosis of MM can be difficult. We have noticed that parakeratotic-like cells, with orange cytoplasm and pyknotic nuclei, are present in many cases of mesothelioma on Papanicolaou-stained cytology slides. Although this cytological finding has been described previously, to our knowledge, there has been no systematic study of this finding. Our study is to determine whether the presence of small parakeratotic / orangeophilic cells (PK-like cells) is specific for the cytodiagnosis of mesothelioma.
A total of 90 body fluid cases were selected from our archived specimens in the Cytology Section at the University of Chicago Hospital accessioned between January 2000 to November 2011. They included 30 cases of mesothelioma, 30 cases of adenocarcinoma, and 30 cases of reactive mesothelial cells.
PK-like cells were present in 83% of the mesothelioma cases, 13% of the adenocarcinoma cases, and 7% of the reactive cases. Our data showed that the presence of PK-like cells has a specificity of 90%, sensitivity of 83%, positive predictive value of 81%, and negative predictive value of 84% for the diagnosis of malignant mesothelioma in body cavity fluids.
The presence of PK-like cells in the effusion specimen, especially in pleural effusions, is a highly specific and moderately sensitive cytological feature for diagnosis of mesothelioma.
恶性间皮瘤（MM）是一种侵袭性肿瘤，预后较差。其发病率在全球范围内呈上升趋势。对积液进行细胞学检查往往是诊断MM的首个机会。然而，MM的细胞学诊断可能具有挑战性。我们注意到，在巴氏染色的细胞学玻片上，许多间皮瘤病例中存在具有橙色细胞质和固缩核的不全角化样细胞。尽管此前已有关于这一细胞学发现的描述，但据我们所知，尚未对该发现进行系统研究。我们的研究旨在确定小的不全角化/嗜橙色细胞（PK样细胞）的存在是否对间皮瘤的细胞诊断具有特异性。
从芝加哥大学医院细胞学部门2000年1月至2011年11月存档的标本中选取了90例体液病例。其中包括30例间皮瘤、30例腺癌和30例反应性间皮细胞病例。
83%的间皮瘤病例、13%的腺癌病例和7%的反应性病例中存在PK样细胞。我们的数据显示，PK样细胞的存在对体腔液中恶性间皮瘤诊断的特异性为90%，敏感性为83%，阳性预测值为81%，阴性预测值为84%。
积液标本中，尤其是胸腔积液中PK样细胞的存在是诊断间皮瘤的一种高度特异性且中度敏感的细胞学特征。
