title: Lymph node hyperplasia: clonal chromosomal and genomic rearrangements. Report of two new cases and literature review.
abstract: Cytogenetic analysis is not routinely performed on lymph node hyperplasia (LH). We describe clonal chromosomal rearrangements in two unrelated cases of LH. Lymph nodes of both patients showed typical morphologic features of benign follicular hyperplasia. Cytogenetic analysis revealed clonal chromosomal rearrangements in both cases. Patient 1 showed interstitial 14q and 6q mosaic deletions, whereas patient 2 showed a terminal 14q mosaic deletion. Fluorescence in situ hybridization with IGH break-apart probes identified a partial deletion of IGH in both cases, but the loss of the LSI IGH in patient 2 and loss of the LSI IGHV in patient 1 were observed on the morphologically normal chromosome 14. In the latter case, the finding of two morphologically normal chromosomes 14 with the IGHV deletion in one of the chromosomes suggested that the first mutational event was the IGH deletion and the second event was the interstitial deletion of chromosome 14 with the IGH intact. Array comparative genomic hybridization performed on both biopsies confirmed the IGH deletion at mosaic, but not the chromosomal deletion. Patient 1 was re-biopsied after 9 months and a marginal zone lymphoma was diagnosed. The finding of clonal cytogenetic abnormalities in LH highlighted the difficulties in interpretation of results and clinical follow-up.
authors.affiliation: Medical Genetics Lab, San Gerardo Hospital, Monza, Italy. Electronic address: n.villa@hsgerardo.org.
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Villa
authors.affiliation: Department of Surgery and Interdisciplinary Medicine, University of Milano-Bicocca, Milan, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Redaelli
authors.affiliation: Medical Genetics Lab, San Gerardo Hospital, Monza, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Lissoni
authors.affiliation: Medical Genetics Lab, San Gerardo Hospital, Monza, Italy.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Saccheri
authors.affiliation: Medical Genetics Lab, San Gerardo Hospital, Monza, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Sala
authors.affiliation: Medical Genetics Lab, San Gerardo Hospital, Monza, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Crosti
authors.affiliation: Medical Genetics Lab, San Gerardo Hospital, Monza, Italy; Department of Surgery and Interdisciplinary Medicine, University of Milano-Bicocca, Milan, Italy.
authors.forename: Leda
authors.initials: L
authors.lastname: Dalprà
authors.affiliation: Tettamanti Research Center, Pediatric Clinic, University of Milano-Bicocca, Milan, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Carrino
authors.affiliation: Department of Haematology, San Gerardo Hospital, Monza, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Pioltelli
authors.affiliation: Department of Surgical Pathology, San Gerardo Hospital, Monza, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Isimbaldi
mesh_terms: D000328:Adult; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D002883:Chromosomes, Human, Pair 14; D002896:Chromosomes, Human, Pair 6; D055028:Comparative Genomic Hybridization; D003582:Cytogenetics; D005260:Female; D017353:Gene Deletion; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D006801:Humans; D006965:Hyperplasia / Q000235:genetics / Q000473:pathology; D007074:Immunoglobulin G / Q000737:chemistry; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D008198:Lymph Nodes / Q000473:pathology*; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics* / Q000276:immunology; D008224:Lymphoma, Follicular / Q000235:genetics* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011379:Prognosis
chemical_list: D007074:Immunoglobulin G; D007143:Immunoglobulin Heavy Chains
keywords: Array CGH; clonal chromosomal rearrangements; fluorescence in situ hybridization; immunoglobulin heavy chain; lymph node hyperplasia