Kakudo Kennichi
Department of Pathology, Cancer Genome Center and Thyroid Disease Center, Izumi City General Hospital, Izumi 594-0073, Japan.
Cancers (Basel). 2022 Feb 5;14(3):812. doi: 10.3390/cancers14030812.
Histopathological diagnosis of papillary thyroid carcinomas (PTCs) is prone to significant observer variation due to different thresholds of -like nuclear changes among pathologists. This gap recently widened due to a defensive attitude by Western pathologists where malpractice litigation is significant. Cases with delicate -like nuclear changes are follicular adenomas when they are noninvasive, follicular carcinomas when invasive, and follicular variant PTCs when they have fully developed PTC-type nuclear features in Asian practice. The different diagnostic threshold of PTC nuclear features resulted in a high (50-90%) incidence of mutation of PTCs in most Asian countries, whereas it was low (35-50%) in most Western patient cohorts. The contamination of indolent -like tumors in the malignant PTC category in Western patient cohorts explains why the gene test identifies aggressive PTCs. However, the test has no prognostic value for Asian PTC patients because most biologically benign or low-risk -like tumors are excluded from PTC. All prognostic analyses of thyroid carcinomas before 2017 must be re-evaluated because most clinical guidelines were established based on data obtained from Western patient cohorts where a significant number of indolent -like tumors were misclassified in the malignant category.
由于病理学家对核仁样改变的阈值不同，甲状腺乳头状癌（PTC）的组织病理学诊断容易出现显著的观察者差异。由于西方病理学家的防御态度（在那里医疗事故诉讼很常见），这种差距最近进一步扩大。在亚洲实践中，具有微妙核仁样改变的病例，若为非侵袭性则为滤泡性腺瘤，若为侵袭性则为滤泡癌，若具有完全发展的PTC型核特征则为滤泡变异型PTC。PTC核特征的不同诊断阈值导致在大多数亚洲国家PTC的BRAF突变发生率较高（50 - 90%），而在大多数西方患者队列中该发生率较低（35 - 50%）。西方患者队列中惰性核仁样肿瘤混入恶性PTC类别中，这解释了为什么BRAF基因检测能识别侵袭性PTC。然而，BRAF检测对亚洲PTC患者没有预后价值，因为大多数生物学上良性或低风险的核仁样肿瘤被排除在PTC之外。2017年之前所有关于甲状腺癌的预后分析都必须重新评估，因为大多数临床指南是基于从西方患者队列获得的数据制定的，在这些队列中大量惰性核仁样肿瘤被错误分类到恶性类别中。
