title: The prevalence and clinical implications of c-kit expression in plasma cell myeloma.
abstract: OBJECTIVE
  To evaluate the clinical implications of c-kit (CD117) expression in plasma cell myeloma (PCM).
  
  
  RESULTS
  We first evaluated the reliability of immunohistochemistry in assessing c-kit expression by comparing the results with those obtained by flow cytometry and gene expression arrays in 22 PCM and in 10 PCM cell lines. Immunohistochemical results showed a perfect concordance with those of flow cytometry; likewise, immunohistochemical and gene expression data were also concordant in all but one PCM and cell lines analysed. Then, we investigated the clinical implications of c-kit immunoreactivity in bone marrow biopsies of 85 PCM patients with a mean follow-up of 41 months. C-kit immunoreactivity was detected in 24 (28.2%) of the 85 cases and it was significantly associated with a high microvessel density, but not with traditional clinicopathological characteristics or with survival.
  
  
  CONCLUSIONS
  Our findings suggest that immunohistochemistry is a reliable indicator of c-kit gene expression and reinforce the notion that approximately one-third of PCM express high levels of c-kit. The lack of association with traditional clinicopathological parameters and patient survival suggests that c-kit expression may not be an adjunct in predicting the clinical course of the disease.
authors.affiliation: Division of Pathology and Laboratory Medicine, European Institute of Oncology and University of Milan, School of Medicine, Italy. giancarlo.pruneri@ieo.it
authors.forename: G
authors.initials: G
authors.lastname: Pruneri
authors.forename: M
authors.initials: M
authors.lastname: Ponzoni
authors.forename: A J M
authors.initials: AJ
authors.lastname: Ferreri
authors.forename: M
authors.initials: M
authors.lastname: Freschi
authors.forename: M
authors.initials: M
authors.lastname: Tresoldi
authors.forename: L
authors.initials: L
authors.lastname: Baldini
authors.forename: M
authors.initials: M
authors.lastname: Mattioli
authors.forename: L
authors.initials: L
authors.lastname: Agnelli
authors.forename: S
authors.initials: S
authors.lastname: Govi
authors.forename: P
authors.initials: P
authors.lastname: Mancuso
authors.forename: A
authors.initials: A
authors.lastname: Agazzi
authors.forename: F
authors.initials: F
authors.lastname: Bertolini
authors.forename: J
authors.initials: J
authors.lastname: Peccatori
authors.forename: S
authors.initials: S
authors.lastname: Bosari
authors.forename: U
authors.initials: U
authors.lastname: Gianelli
authors.forename: G
authors.initials: G
authors.lastname: Viale
authors.forename: A
authors.initials: A
authors.lastname: Neri
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D045744:Cell Line, Tumor; D005260:Female; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis; D008875:Middle Aged; D009101:Multiple Myeloma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D020411:Oligonucleotide Array Sequence Analysis; D011509:Proteoglycans / Q000032:analysis; D019009:Proto-Oncogene Proteins c-kit / Q000096:biosynthesis* / Q000235:genetics; D016019:Survival Analysis; D053667:Syndecans
chemical_list: D008562:Membrane Glycoproteins; D011509:Proteoglycans; D053667:Syndecans; D019009:Proto-Oncogene Proteins c-kit