title: Hyaline vascular Castleman's disease with HMGIC rearrangement in follicular dendritic cells: molecular evidence of mesenchymal tumorigenesis.
abstract: Chromosomal aberrations involving chromosome segment 12q13-15 are a common finding in a variety of benign mesenchymal tumors. The target gene encodes for HMGIC, a member of the high mobility group protein family. These proteins act as architectural transcription factors. HMGIC plays a role as a common genetic denominator in benign mesenchymal tumorigenesis. We report a case of hyaline vascular Castleman's disease with intragenic HMGIC rearrangement, due to a clonal cytogenetic aberration involving the long arm of chromosome 12 [46,XX, add(1)(q21),der(6)t(6;12) (q23;q15),add(7)(p22), -9,inv(9)(p11q13),del(12)(q15),+mar] obtained after short-term primary cultures. A combined immunocytologic-cytogenetic approach enabled us to demonstrate the exclusive presence of HMGIC rearrangement in anti-CD21 reactive follicular dendric cells. This finding confirms that a clonal proliferation of follicular dendritic cells occurs in the hyaline vascular variant of Castleman's disease. It also provides a possible molecular pathway explaining stromal overgrowths and stromal neoplasms developing from this disorder.
authors.affiliation: Department of Pathology, University Hospital St Raphael, Katholieke Universiteit Leuven, Leuven, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Cokelaere
authors.forename: M
authors.initials: M
authors.lastname: Debiec-Rychter
authors.forename: C
authors.initials: C
authors.lastname: De Wolf-Peeters
authors.forename: A
authors.initials: A
authors.lastname: Hagemeijer
authors.forename: R
authors.initials: R
authors.lastname: Sciot
mesh_terms: D000328:Adult; D005871:Castleman Disease / Q000150:complications / Q000235:genetics* / Q000473:pathology*; D002881:Chromosomes, Human, Pair 12; D020566:Dendritic Cells, Follicular / Q000473:pathology*; D005260:Female; D015321:Gene Rearrangement; D025743:HMGA2 Protein / Q000235:genetics*; D006801:Humans; D006818:Hyalin; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008198:Lymph Nodes / Q000473:pathology; D008637:Mesenchymoma / Q000209:etiology / Q000235:genetics / Q000473:pathology
chemical_list: D025743:HMGA2 Protein