Diagnostically relevant updates to the 2017 WHO classification of lymphoid neoplasms

Abstract

The recent 2017 WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues contains a number of updates under the category of lymphoid neoplasms. These changes include introduction of new entities, amended classification or terminology, and addition of newly discovered diagnostic and molecular features. In this review, we perform a focused, concise summary of selected lymphoid neoplasms and discuss changes in their classification. Rather than a comprehensive overview, we place specific emphasis on important and diagnostically relevant aspects of each entity that are novel or different from the previous WHO iteration and bring the practicing pathologist quickly up to speed with the updated classification.

Keywords: In situ neoplasia; Lymphoid neoplasms; Lymphoid tumors; Lymphoma; WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues.