title: Immunohistochemistry accurately predicts FGFR3 aberrant expression and t(4;14) in multiple myeloma.
abstract: The t(4;14) translocation detected by fluorescence in situ hybridization (FISH) is an independent prognostic factor for an adverse outcome of multiple myeloma (MM). Because t(4;14) uniquely results in fibroblast growth factor receptor 3 (FGFR3) expression, decalcified, paraffin-embedded bone marrow biopsies were immunostained for FGFR3, and its expression was correlated with the t(4;14) status. FISH detected t(4;14) in 16 (19%) of 85 MM patient specimens, and immunocytochemistry detected aberrant FGFR3 expression in 13 (15%). Twelve (75%) t(4;14)-positive cases expressed FGFR3, and 12 (92%) FGFR3-positive cases harbored a t(4;14). FGFR3 expression and t(4;14) were strongly correlated (P < .001). FGFR3 expression by immunohistochemistry was associated with the immunoglobulin A (IgA) isotype (P < .001), a shorter progression-free survival (median, 11.5 versus 25.8 months; P < .001), and a shorter overall survival (median, 19.2 versus 46.3 months; P < .001).
authors.affiliation: Department of Laboratory Hematology, Princess Margaret Hospital/University Health Network, McLaughlin Center for Molecular Medicine, University of Toronto, ON, Canada. hong.chang@uhn.on.ca
authors.forename: Hong
authors.initials: H
authors.lastname: Chang
authors.forename: A Keith
authors.initials: AK
authors.lastname: Stewart
authors.forename: Xiao Ying
authors.initials: XY
authors.lastname: Qi
authors.forename: Zhi Hua
authors.initials: ZH
authors.lastname: Li
authors.forename: Qi Long
authors.initials: QL
authors.lastname: Yi
authors.forename: Suzanne
authors.initials: S
authors.lastname: Trudel
mesh_terms: D000328:Adult; D000368:Aged; D002883:Chromosomes, Human, Pair 14; D002894:Chromosomes, Human, Pair 4; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D005820:Genetic Testing; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000175:diagnosis* / Q000235:genetics*; D011237:Predictive Value of Tests; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D051498:Receptor, Fibroblast Growth Factor, Type 3; D017468:Receptors, Fibroblast Growth Factor / Q000235:genetics*; D014178:Translocation, Genetic
chemical_list: D017468:Receptors, Fibroblast Growth Factor; C496365:FGFR3 protein, human; D011505:Protein-Tyrosine Kinases; D051498:Receptor, Fibroblast Growth Factor, Type 3