Follicular helper T-cell lymphoma

Source:  Follicular helper T-cell lymphoma    Tag:  ebv positive lymphoma
: a B-cell–rich variant of T-cell lymphoma
Publication date: August 2015
Source:Annals of Diagnostic Pathology, Volume 19, Issue 4
Author(s): S.J. Ruiz , C.V. Cotta
Follicular helper T-cell lymphoma is a recently described variant of T-cell lymphoma sharing the cell of origin with angioimmunoblastic T-cell lymphoma and with primary cutaneous CD4-positive small/medium T-cell lymphoma. To better characterize the morphologic and immunophenotypic features of follicular helper T-cell lymphoma, a series of 4 confidently diagnosed cases are analyzed. The overall morphologic pattern significantly overlaps with that of progressive transformation of germinal centers in 3 cases and with follicular hyperplasia in 1. Detection of large, clustered, atypical T-cells is an important feature differentiating follicular T-cell lymphoma from benign, reactive processes such as progressive transformation of germinal centers. The abnormal T-cells have an immunophenotype identical to that of follicular helper T-cells in all cases. Clonal T-cell populations are detected in all cases. A characteristic setting follicular T-cell lymphomas apart from most other T-cell lymphomas is the abundance of small, mature B-cells. Differences from angioimmunoblastic T-cell lymphoma include the absence of proliferating vessels or of Epstein-Barr virus–positive immunoblasts.