title: Peripheral T-cell lymphoma with involvement of the expanded mantle zone.
abstract: Peripheral T-cell lymphoma (PTCL) with a nodular architecture is rare. Recently, two variants have been described with infiltration of the B-cell follicle, one variant that localizes to the marginal zone with a so-called perifollicular growth pattern, and a variant that localizes to the germinal center. These lymphomas have a CD4+ phenotype and may express Bcl-6. We have studied five similar cases of PTCL with involvement of the B-cell follicle. However, our cases differ from the cases previously described by their predominant and frequently patchy involvement of the expanded mantle zone of the B-cell follicle at onset. Later biopsies in three of the cases show diffuse infiltration of the lymph node, without features of angioimmunoblastic TCL (AILT). All cases expressed Bcl-6 in addition to CD4. Cytogenetics was available in four of the cases but revealed no recurrent chromosomal aberrations or changes associated with other types of PTCL. No mutations of the BCL-6 gene were observed. Together, the cases seem to have an intermediately aggressive clinical behavior. Whether our cases are part of a spectrum of PTCLs that encompasses previously described variants with predominant marginal zone or germinal center infiltration or they represent a separate T-cell lymphoma type remains to be demonstrated by a study of more of such cases.
authors.affiliation: Department of Pathology, The Norwegian Radium Hospital, University of Oslo, Oslo, Norway. ida.m.munster.ikonomou@radiumhospitalet.no
authors.forename: Ida Münster
authors.initials: IM
authors.lastname: Ikonomou
authors.forename: Anne
authors.initials: A
authors.lastname: Tierens
authors.forename: Gunhild
authors.initials: G
authors.lastname: Troen
authors.forename: Hege Vangstein
authors.initials: HV
authors.lastname: Aamot
authors.forename: Sverre
authors.initials: S
authors.lastname: Heim
authors.forename: Grete F
authors.initials: GF
authors.lastname: Lauritzsen
authors.forename: Helen
authors.initials: H
authors.lastname: Vålerhaugen
authors.forename: Jan
authors.initials: J
authors.lastname: Delabie
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D015704:CD4 Antigens / Q000378:metabolism; D003131:Combined Modality Therapy; D004268:DNA-Binding Proteins / Q000378:metabolism; D017809:Fatal Outcome; D005260:Female; D018858:Germinal Center / Q000473:pathology; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D020522:Lymphoma, Mantle-Cell / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D016411:Lymphoma, T-Cell, Peripheral / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D051560:Proto-Oncogene Proteins c-bcl-6; D012074:Remission Induction
chemical_list: C084103:BCL6 protein, human; D014408:Biomarkers, Tumor; D015704:CD4 Antigens; D004268:DNA-Binding Proteins; D051560:Proto-Oncogene Proteins c-bcl-6