Updates of Peripheral T Cell Lymphomas Based on the 2017 WHO Classification.

PURPOSE OF REVIEW: This review will describe and update the readers on the recent changes of the 2017 WHO classification in regard to peripheral T cell lymphomas.

RECENT FINDINGS: Significant advances in molecular studies have resulted in revisions of the classification as well as introduction of provisional entities (such as breast implant-associated ALCL, nodal PTCL with TFH phenotype). Major advances in molecular and gene expression profiling have expanded our knowledge of T cell lymphomas, including updates in the diagnostic criteria and sub-classification which will facilitate in improving patient care and research.