阑尾及结直肠肿瘤2019年第5版WHO分类变更解读

Interpretation of the 5th edition(2019)WHO classification of digestive system(appendix and colorectal)tumors

2019年第5版(以下简称“第5版”)世界卫生组织(WHO)消化系统肿瘤新分类在2010年第4版(以下简称“第4版”)的基础上对阑尾及结直肠肿瘤的相关内容做了较大的改动,增加了引言、锯齿状病变和息肉、黏液性肿瘤等内容,将不再推荐使用无蒂锯齿状息肉或腺瘤的诊断名称,改称为无蒂锯齿状病变,增加了未分类锯齿状腺瘤。第5版把混合性腺神经内分泌癌改称为混合性神经内分泌-非神经内分泌肿瘤,并指出两者具有克隆相关性,杯状细胞类癌不再被认为是神经内分泌肿瘤的一个亚型,改称为杯状细胞腺癌。第5版进一步细化结直肠腺癌的内容,把血管浸润分为肠壁内血管浸润和肠壁外血管浸润(超出黏膜肌),后者发生率高于前者,而且预后更差。第5版认为肿瘤出芽及差分化癌细胞团是上皮间质转化的征兆,并且应用RNA测序或基于基因芯片技术,以肿瘤基因谱网络和转录组学分析的数据为基础,提出了共识分子分型。同时,第5版也更新了阑尾及结直肠肿瘤的TNM分期。为了帮助医务人员尽快熟悉第5版变更的内容,本文就更新后第4版与第5版的异同进行总结。

The contents related to appendix and colorectal tumors in the new 5th edition World Health Organization(WHO)classification of digestive tract tumors in 2019(hereinafter referred to as"the 5th edition")have considerably changed compared with those in the 4th edition WHO classification in 2010(hereinafter referred to as"the 4th edition").In addition,contents related to disease evolution in introduction,serrated lesions,polyps and mucinous tumors,and so on have been newly added.The use of the diagnostic name of sessile serrated polyps or adenomas is no longer recommended in the 5th edition;alternatively,it has been renamed as sessile serrated lesions,and the new term"unclassified serrated adenomas"has been included.The term"mixed adenoneuroendocrine carcinoma"has been replaced with"mixed neuroendocrine-non-neuroendocrine tumors,"and the clonal correlation between the two terms has been emphasized.The goblet cell carcinoid is no longer considered a subtype of neuroendocrine neoplasms;hence,it is renamed goblet cell adenocarcinoma.The 5th edition has further improved content on colorectal adenocarcinoma and categorizes vascular infiltration into intramural and extramural(beyond the mucosal muscles)vascular infiltration.Extramural vascular infiltration,whose prognosis is worse,occurs more frequently than intramural vascular infiltration.Tumor budding or the presence of poorly differentiated clusters is considered as an omen of epithelial-mesenchymal transition.Four main consensus molecular subtype groups have been proposed based on RNA sequencing or gene chip technology and the data from the Cancer Genome Atlas and transcriptome profiling.The TNM staging for appendix and colorectal tumors has also been updated in the 5th edition.The changes in the contents of the 5th edition have been summarized to help medical staff become familiar with them as soon as possible.