Floral variant of follicular lymphoma: immunological and molecular studies support a neoplastic process

In recent reports of the so-called «floral variant» of follicular lymphoma, an unusual variant of follicular lymphoma mimicking progressive transformation of germinal centers, questions have been raised regarding whether this process represents a malignant lymphoma. We studied 19 examples of the floral variant of follicular lymphoma and report our light microscopic, immunohistochemical, and molecular diagnostic findings. Morphologic changes consisted of effacement of normal lymph node architecture by follicles composed of atypical lymphocytes. The follicles were surrounded by prominent mantle zones that invaginated irregularly into the follicle centers, often imparting a «floral » appearance. Sufficient material was available for immunophenotypic or genotypic studies in 15 biopsies