B-CELL LYMPHOID NEOPLASMS IN THE 5TH EDITION OF THE WHO CLASSIFICATION OF HEMATOLYMPHOID TUMORS (2022). 2. Mature B-cell neoplasms, plasma cell neoplasms and other diseases with paraproteins

Abstract

Summary. The in-depth insight into the pathogenesis of lymphoid neoplasms requires the continuous revision of the classification of these diseases. In 2022, World Health Organization specialists prepared the regular 5th issue of the Classification of Hematolymphoid Tumors. Our previous report (Oncology 2023; 25 (2): 89–103) discussed the key milestones in the development of the modern WHO classification of the tumors of lymphoid and hematopoietic tissues, the basic provisions of the new (2022) classification of hematolymphoid tumors. Such categories as “tumor-like lesions with B-cell predominance” and “precursor B-cell neoplasms” were reviewed in detail. The second part of the report aims at listing and explaining the principal changes in the 5th issue of the classification related to the mature B-cell neoplasms, plasma cell neoplasms and other diseases with paraproteins. A particular attention is focused on the practical aspects of using the new classification for verifying B-cell lymphoid malignancies taking into account the definitive molecular-biological features of the clinicopathologically distinct entities and subtypes. The changes to the classification are the key to choosing the strategies for the therapy of the hematological malignancies allowing for the improvement of the clinical outcomes.