The broad landscape of follicular lymphoma: Part I

Abstract

Summary Follicular lymphoma is a neoplasm derived from follicle center B cells, typically both centrocytes and centroblasts, in variable proportions according to the lymphoma grading. The pattern of growth may be entirely follicular, follicular and diffuse, and rarely completely diffuse. It represents the second most common non-Hodgkin lymphoma, after diffuse large B-cell lymphoma and is the most common low-grade mature B-cell lymphoma in western countries. In the majority of cases, follicular lymphoma is a nodal tumor, occurring in adults and frequently associated with the translocation t(14;18)(q32;q21)/IGH-BCL2. However, in recent years the spectrum of follicular lymphoma has expanded and small subsets of follicular lymphoma, which differ from common follicular lymphoma, have been identified and included in the current 2017 WHO classification. The aim of our review is to describe the broad spectrum of follicular lymphoma, pointing out that the identification of distinct clinicopathological variants of follicular lymphoma is relevant for patient outcomes and choice of treatment.

A novel diagnostic approach for the classification of small B-cell lymphoid neoplasms based on the NanoString platform

“…Another approach was, as one of the ancillary diagnostic methods, the accuracy of the classification could be improved if specific genetic or cytogenetic aberrations were also detected. The IGH-BCL2 translocation is a hallmark of FL and is present in 80% FL cases and even 90% in low-grade FL cases, but rarely identified (3%) in non-FL SBCLN cases 19 , 20 . Similarly, MYD88 L265P and BRAF V600E mutation was specifically detected in >90% LPL/WM and HCL cases, respectively.…”

The broad landscape of follicular lymphoma: Part II

“…In recent years, histological and clinical spectrum of germinal center derived B-cell neoplasms has expanded, leading to the conclusion that FL represents a far more heterogeneous entity than originally appreciated. In the previous review we illustrated FL variants encountered in diagnostic practice 2 . Surgical pathologists and hematopathologists should be aware of the broad FL landscape, in order to avoid diagnostic pitfalls and get to more accurate diagnosis.…”