title: Follicular lymphoma grade 3B.
abstract: Follicular lymphoma (FL) grade 3B (FL3B) is defined as FL with more than 15% centroblasts per high resolution field present as solid sheets. Coexistence with diffuse large B-cell lymphoma (DLBCL) is frequent. In contrast to other FL, FL3B frequently lack CD10 expression (approximately 50% of cases), show lower probability of BCL2 expression (69% positive) and increased TP53 expression (31% positive). The t(14;18) hallmark translocation of FL is present in only around 13% of FL3B. In contrast, translocations affecting the BCL6 locus in 3q27 are frequent (44%). Overall, FL3B in many features resembles DLBCL. The presence of a diffuse component in FL3B has been related to an unfavorable outcome except for pediatric FL3B that presents in 60% of the cases this DLBCL component. In this chapter we sought to review the present knowledge on morphological, cytogenetic and molecular features in FL3B.
authors.affiliation: Institute of Human Genetics, University Hospital Schleswig-Holstein, Campus Kiel, Christian-Albrechts University Kiel, Schwanenweg 24, D-24105 Kiel, Germany. isalaverria@medgen.uni-kiel.de
authors.forename: Itziar
authors.initials: I
authors.lastname: Salaverria
authors.forename: Reiner
authors.initials: R
authors.lastname: Siebert
mesh_terms: D000328:Adult; D001402:B-Lymphocytes / Q000378:metabolism / Q000473:pathology*; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D002648:Child; D002883:Chromosomes, Human, Pair 14 / Q000737:chemistry / Q000235:genetics; D002887:Chromosomes, Human, Pair 18 / Q000737:chemistry / Q000235:genetics; D015897:Comorbidity; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D008224:Lymphoma, Follicular / Q000453:epidemiology / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000453:epidemiology / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D015260:Neprilysin / Q000235:genetics* / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics* / Q000378:metabolism; D051560:Proto-Oncogene Proteins c-bcl-6; D012720:Severity of Illness Index; D014178:Translocation, Genetic; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism
chemical_list: C084103:BCL6 protein, human; D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051560:Proto-Oncogene Proteins c-bcl-6; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D015260:Neprilysin