The 2007 WHO classification of tumors of the nervous system: controversies in surgical neuropathology

Controversy surrounds the recent 2007 WHO Classification of Tumours of the Nervous System. A number of nosologic issues remain to be resolved, some a reflection of conceptual disagreement, others the result of inadequate data to permit their definitive resolution. Among these and discussed herein are (i) the nosologic place of highly anaplastic oligoastrocytic tumors, (ii) the forms and significance of microvascular changes in high-grade gliomas, (iii) the makeup of the glioneuronal tumors category, (iv) the subclassification of pineal parenchymal tumors of intermediate type, and (v) the classification of principle forms of mesenchymal neoplasms, specifically hemangiopericytoma and solitary fibrous tumor. These issues and others are the substance of this and an upcoming companion article.     

The new WHO classification of digestive neuroendocrine tumors

A new classification of digestive neuroendocrine neoplasms has been formulated in the 2010 revision of the WHO classification of digestive tumors. The principles of this new classification are different from those used in the previous one and the terminology is quite novel. Five main categories are recognized: neuroendocrine tumor G1; neuroendocrine tumor G2; neuroendocrine carcinoma, small cell type; neuroendocrine carcinoma, large cell type; mixed adenoneuroendocrine carcinoma (a new term for mixed tumors). This new classification will change the habits of the clinicians, familiar with the previous classification, which formed the basis for deciding the therapeutic strategy and the type of patient management. Attention must be paid when establishing the concordance between the new classification and the previous one and when reclassifying a previously diagnosed case, now under follow-up. Recommendations are proposed for the redaction of the pathological reports in this period of transition.     

2004年WHO肾脏肿瘤组织学分类简介

新版WHO有关“泌尿系统和男性生殖器官肿瘤病理学和遗传学”于2004年出版,由Eble等主编,但仍沿袭了老一辈泌尿系统病理学家Mostofi制订的WHO“泌尿系统和男性生殖系统肿瘤病理学分类”的思路和风格。与1998年版本拉。或早前的版本相比,多有修正之处,并增添了许多新观点,对泌尿系统和男性生殖系统疾病病理学的发展起了引导作用。本文就其中的肾脏肿瘤病理学谈一些认识。     

WHO中枢神经系统肿瘤分类(2007)评介

《WHO中枢神经系统肿瘤分类》第4版（以下简称第4版分类）于2007年6月由国际癌症研究机构（International Agency for Researchon Cancer,IARC）正式出版,WHO出版社发行,反映了自第3版WHO神经系统肿瘤分类（2000）出版㈨以来神经肿瘤病理学领域的重要进展。     

Development of the WHO classification of tumors of the central nervous system: a historical perspective

The classification of brain tumors has undergone numerous changes over the past half century. The World Health Organization has played a key role in the effort. Four versions of its Classification of Tumours of the Central Nervous System have been published. The present work chronicles their progress, placing emphasis on the historical context of the earliest effort.     

Papillary glioneuronal tumor is a new nosological entity in the WHO classification of central nervous system tumors (2007)

The paper describes a case of cystic papillary glioneuronal tumor of the temporal lobe in an 18-year-old girl. It is shown that in addition to the characteristic histological pattern, the diagnosis of this rare neoplasm recently included into the WHO classification text s should be verified by the immunohistological evidence suggesting the coexpression of glial and neuronal markers.     

5 109例中枢神经系统肿瘤WHO新分类统计分析

目的 探讨新的WHO分类在中枢神经系统肿瘤病理诊断及统计学分析中的意义。方法 对1999年7月～2002年6月3年间华山医院诊治的5109例中枢神经系统肿瘤采用免疫细胞化学ABC法及20余种抗体标记，依据WHO神经系统肿瘤新分类作病理诊断，并作统计分析。结果 在5109例肿瘤中，按WHO(2000)分类，属神经系统肿瘤有3981例，其中神经上皮组织肿瘤l498例(占37．64％)，颅脊神经肿瘤536例(占13．46％)，脑膜肿瘤1379例(占34．64％)，其中脑膜上皮组织肿瘤1130例(占28．38％)和脑膜间叶组织肿瘤249例(占6．25％)。未定组织来源肿瘤(血管母细胞瘤)110例(占2．76％)。淋巴瘤和造血组织肿瘤72例(占1．80％)，胚生殖细胞肿瘤52例(占1．32％)，鞍区颅咽管瘤139例(占3．49％)和转移性肿瘤195例(占4．90％)。同期的非神经系统肿瘤，即垂体腺肿瘤1042例(占20．39％)和其他类肿瘤86例(占1．68％)。结论 脑膜肿瘤和神经上皮组织肿瘤中少突胶质细胞肿瘤比例均有升高，认识先进仪器和设备并应用于肿瘤诊断，并认识少突胶质肿瘤病理形态学本质及胶质母细胞瘤新概念，以及坚持WHO分类的原则是重要的。     

2010年版消化系统肿瘤WHO分类解读

新版WHO肿瘤分类消化分册[1]经过多次及多个专业的共识会议定稿,最终于2010年11月正式出版发行,书名也由<消化系统肿瘤病理学和遗传学>(Pathology and Genetics of Tumours of the Digestive System)(以下简称旧版)[2]更改为<消化系统肿瘤WHO分类>(WHOClassification of Tumours of the Digestive System)(以下简称新版).     

2010年版消化系统肿瘤WHO分类解读

新版WHO肿瘤分类消化分册[1]经过多次及多个专业的共识会议定稿,最终于2010年11月正式出版发行,书名也由<消化系统肿瘤病理学和遗传学>(Pathology and Genetics of Tumours of the Digestive System)(以下简称旧版)[2]更改为<消化系统肿瘤WHO分类>(WHOClassification of Tumours of the Digestive System)(以下简称新版).     

学习和掌握肿瘤的WHO分类,提高病理诊断和研究的水平

半个世纪以来,尤其是近20年来,肿瘤学的基础和临床研究取得了巨大进展。肿瘤分子生物学研究从基因和分子水平阐明肿瘤的发生发展规律,揭示了肿瘤细胞与正常细胞之问的差异,认识到大多数肿瘤是体细胞突变导致后天获得的遗传性疾病,对癌症本质是一种遗传性疾病（cancer is a genetic disease）的认识已渗入到临床肿瘤学的各个方面,在肿瘤的分类、诊断和治疗中许多观念发生了重大变化。世界卫生组织（WHO）在新世纪初出版的肿瘤WHO分类系列丛书,在肿瘤分类和诊断上反映了这些观念的变化。     

Pathology and molecular genetics of oligodendroglial tumors

Oligodendroglial gliomas are second only to astrocytic gliomas in frequency. The lack of stringent diagnostic criteria cause high interobserver variation in regard to classification and grading of these tumors. Previous studies have described oligodendrogliomas with features that overlap with those of neurocytic tumors, thus further complicating diagnostic decisions. The increasing need for standardized diagnostic criteria in this subset of gliomas is emphasized by the benefit of adjuvant therapies in patients with anaplastic oligodendrogliomas. Characteristic chromosomal aberrations have been successfully determined for oligodendroglial tumors in recent years. In contrast to astrocytomas, however, no genes in the affected regions have been clearly linked to their pathogenesis. However, the molecular findings promise to be helpful for diagnostic and therapeutic decisions. This review compiles clinical, pathological, and molecular genetic findings on WHO grades II and III oligodendrogliomas and oligoastrocytomas.     

Tumour-like lesions of the salivary glands. The new WHO classification.

Tumour-like lesions must be distinguished from true tumours of the salivary glands. In the new WHO classification of salivary gland tumours seven entities were considered: sialadenosis, oncocytosis (diffuse oncocytosis and focal adenomatous oncocytic hyperplasia), necrotizing sialometaplasia (salivary gland infarction), benign lymphoepithelial lesion (chronic myoepithelial sialadenitis), salivary duct cysts (mucoceles of the minor salivary glands of extravasation or retention type, cysts of the major salivary glands, ranula and dysgenetic polycystic disease of the parotid gland), chronic sclerosing sialadenitis of the submandibular gland (Küttner tumour), and cystic lymphoid hyperplasia in AIDS. The main topics of clinical data and pathohistology were described and documented by the results of the Salivary Gland Register in Hamburg (1965-1989).     

Evolving concepts and new entities in the 2017 WHO classification of salivary gland tumors

For the past decades, many new salivary gland entities have been described which are somewhat related to the discovery of unique molecular alterations in these tumors. The 4th edition of World Health Organization (WHO) classification of head and neck tumors has included several new entities, e.g. secretory carcinoma, sclerosing polycystic adenosis and intercalated duct lesions and modified several carcinomas, e.g. clear cell carcinoma, intraductal carcinoma and polymorphous adenocarcinoma. In addition, in the 4th edition, the concept of high grade transformation has been introduced. In this review, we aimed to illustrate the major changes in the WHO classification, focusing on the rationale behind these changes, the morphologic features of the new described entities and the ancillary diagnostic tools that may help with the differential diagnoses of salivary gland neoplasms.     

Integrative classification of morphology and molecular genetics in central nervous system malformations

We propose a scheme to classify central nervous system (CNS) malformations that integrates morphology and genetics by using patterns of genetic expression as its basis. The precise genetic mutations are not necessary to know in all cases. The premises of this classification are (1) genetic expression in the neural tube follows gradients in the axes that are established at the time of gastrulation: vertical (dorsoventral and ventrodorsal); rostrocaudal; mediolateral. (2) Overexpression in one of these gradients generally results in duplication or hyperplasia of structures, or ectopic segmental (i.e., neuromeric) expression. (3) Underexpression in a gradient generally results in hypoplasia, noncleavage in the midline of paired structures or segmental deletion of neuromeres. These gradients may also affect the formation and migration of neural crest tissue, affecting non-neural structures such as the face in the case of the mesencephalic neural crest, or induction of paraxial mesodermal in the posterior fossa. Additional criteria of the new classification allow for other genetic influences on developmental processes, such as cellular lineage, exemplified by tuberous sclerosis, and hemimegalencephaly. It is essential that the CNS be considered as a whole and classification not be regionalized, as to the cerebral cortex, because the limit of the rostrocaudal gradient may account for variability in clinical manifestations.     

The 2007 World Health Organisation classification of tumours of the central nervous system, comparison with 2000 classification

WHO Classification of Tumours of the Central Nervous System from the 2007 is distinguished from the previous 2000 classification by a few conceptual modifications, changes in the terminology and seven newly codified tumour entities. The text shows a short comparison of both classifications emphasising the most important changes from the surgical neuropathology point of view. The newly codified entities are: angiocentric glioma, pilomyxoid astrocytoma, papillary glioneuronal tumor, rosette-forming glioneuronal tumor of the 4th ventricle, papillary tumour of the pineal region, spindle cell oncocytoma and pituicytoma. Mostly, they are rare tumours already known from the literature. Based on new knowledge from the molecular pathology the paragraphs about tumour genetics were markedly changed. The complexity and diversity of tumours of the nervous system is enormous, and, not surprisingly, some problematic questions of classification and grading remain unresolved.