The 2022 classifications of B-cell lymphomas and plasma cell disorders

Abstract

Tumors derived from B-lymphocytes at their various stage of maturation and differentiation (human B-cell lymphomas and leukemias) are the commonest hematological malignancies. Previous editions of the World Health Organization (WHO) classification of Hematopoietic and lymphoid neoplasms, edited in 2001, 2008, and 2017, intended to standardize the diagnosis of hemopoietic neoplasms overall. Recent advances in lymphoma research, mostly based on genomic as well as molecular analyses, have dramatically expanded our knowledge of lymphoma biology, this leading to improved diagnostic criteria, upgrading of provisional entities, and identification of new tumor types. In 2022, two frameworks for classifying hematolymphoid neoplasms were proposed: the WHO-HAEM5 and the International Consensus Classification (ICC). Since a common nosography is essential for advancing health science and providing a foundation for precision medicine, it is critical to recognize possible differences and harmonize the diverse approaches. In this article, the Authors summarizes the key differences between the two most recent classifications by focusing on tumors derived from B-lymphocytes and plasma cells.