title: A B-cell lymphoma-associated chromosomal translocation in a progressive transformation of germinal center.
abstract: Progressive transformation of germinal center (PTGC) is a pattern of lymph node reactive hyperplasia. It can also be the predominant pattern in a hyperplastic lymph node known as florid PTGC. It is characterized histologically by the expansion of the mantle zone lymphocytes into both the adjacent sinusoids and germinal centers. The lymphocytes destroying the germinal centers are predominantly B cells, with a minor population of T cells. Morphologically, it can be confused with nodular lymphocyte-predominant Hodgkin disease (NLPHD) because of its nodular pattern and because of the presence of large cells that can be incorrectly identified as lymphocytic and histiocytic cells. A relationship between PTGC and NLPHD remains unclear, and many authors have suggested that PTGC can represent a precursor lesion of NLPHD. Here we report the first karyotype obtained in PTGC, in a 12-year-old boy. It shows a t(3;22)(q27;q11) translocation, probably involving the BCL6 gene. This translocation has previously been described in diffuse large B-cell lymphomas and in NLPHD with BCL6 rearrangement. This finding offers an insight into a possible tumorigenic pathway from PTGC to NLPHD. Further studies will be required to confirm this hypothesis.
authors.affiliation: Department of Pathology, Centre Hospitalo-Universitaire Sainte-Justine, 3175 chemin de la Côte Sainte-Catherine, Montréal, Québec, Canada H3T 1C5. dorothee.dal_soglio.hsj@ssss.gouv.qc.ca
authors.forename: Dorothée
authors.initials: D
authors.lastname: Bouron-Dal Soglio
authors.forename: Françoise
authors.initials: F
authors.lastname: Truong
authors.forename: Raouf
authors.initials: R
authors.lastname: Fetni
authors.forename: Sawcene
authors.initials: S
authors.lastname: Hazourli
authors.forename: Josette
authors.initials: J
authors.lastname: Champagne
authors.forename: Luc Laurier
authors.initials: LL
authors.lastname: Oligny
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Fournet
mesh_terms: D005871:Castleman Disease / Q000235:genetics / Q000473:pathology; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D002648:Child; D002871:Chromosome Banding; D002892:Chromosomes, Human, Pair 22; D002893:Chromosomes, Human, Pair 3; D018858:Germinal Center / Q000473:pathology*; D006801:Humans; D007124:Immunoenzyme Techniques; D007621:Karyotyping; D016393:Lymphoma, B-Cell / Q000235:genetics* / Q000473:pathology*; D008297:Male; D014178:Translocation, Genetic / Q000235:genetics*