Fourth Edition Of WHO Classification Research Articles

Adult type diffuse gliomas in the new 2021 WHO Classification.

Adult-type diffuse gliomas represent a group of highly infiltrative central nervous system tumors with a prognosis that significantly varies depending on the specific subtype and histological grade. Traditionally, adult-type diffuse gliomas have been classified based on their morphological features with a great interobserver variability and discrepancy in patient survival even within the same histological grade. Over the last few decades, advances in molecular profiling have drastically changed the diagnostic approach and classification of brain tumors leading to the development of an integrated morphological and molecular classification endowed with a more clinically relevant value. These concepts were largely anticipated in the revised fourth-edition of WHO classification of central nervous system tumors published in 2016. The fifth-edition (WHO 2021) moved molecular diagnostics forward into a full integration of molecular parameters with the histological features into an integrative diagnostic approach. Diagnosis of adult type diffuse gliomas, IDH mutant and IDH-wildtype has been simplified by introducing revised diagnostic and grading criteria. In this review, we will discuss the most recent updates to the classification of adult-type diffuse gliomas and summarize the essential diagnostic keys providing a practical guidance to pathologists.

Clinical practice guidelines for the management of adult diffuse gliomas.

To follow the revision of the fourth edition of WHO classification and the recent progress on the management of diffuse gliomas, the joint guideline committee of Chinese Glioma Cooperative Group (CGCG), Society for Neuro-Oncology of China (SNO-China) and Chinese Brain Cancer Association (CBCA) updated the clinical practice guideline. It provides recommendations for diagnostic and management decisions, and for limiting unnecessary treatments and cost. The recommendations focus on molecular and pathological diagnostics, and the main treatment modalities of surgery, radiotherapy, and chemotherapy. In this guideline, we also integrated the results of some clinical trials of immune therapies and target therapies, which we think are ongoing future directions. The guideline should serve as an application for all professionals involved in the management of patients with adult diffuse glioma and also a source of knowledge for insurance companies and other institutions involved in the cost regulation of cancer care in China and other countries.

Immunohistochemical Biomarkers in Diagnosis of Hematolymphoid Neoplasms of Endocrine Organs.

The hematolymphoid infiltrations are challenging lesions in endocrine organs and tissues. The fourth edition of WHO classification of tumors of endocrine organs and the fourth edition of WHO classification of tumors of hematopoietic and lymphoid tissues are recently published. The updates in both fields include some new disease descriptions and prognostic markers. Our aim in this review article is to give practical diagnostic information about the most frequently seen hematolymphoid involvements of the pituitary gland, thyroid, and adrenal tissue. We designed the text in the order of organs and the contents according to the disease frequency. The pituitary gland and cellar region are the most frequently involved with Langerhans cell histiocytosis. Although it is very rare, Erdheim-Chester disease has recently been included in the classification and still needs more clear diagnostic definitions. Lymphoproliferative thyroid lesions and presentations create diagnostic problems for the pathologists. IGG4-related disease and its relation with thyroiditis is a new concept. There are many unknowns on pathobiology of the disease spectrum and discussion on defined diagnostic criteria of the IGG4-related thyroid diseases. The overlapping features of thyroiditis and primary thyroid lymphomas also create diagnostic difficulties. The frequently recognized primary hematolymphoid lesions of the endocrine organs may not be difficult to diagnose since they are expected lesions. The secondary involvement of hematolymphoid neoplasia may be more difficult to diagnose for an endocrine pathologist. In this review article, we aim to give brief description of the diseases and practical diagnostic approach by using optimum markers guided by the latest WHO classifications.

The fourth edition of WHO classification of tumours of bone: an introduction

The fourth edition of WHO classification of tumours of bone: an introduction