title: The relationship between flow-cytometric and immunohistochemically detected c-erbB-2 expression, grade and DNA ploidy in breast cancer.
abstract: Quantification of c-erbB-2 and its relationship with other prognostic markers using flow cytometry has been examined. In this study a level for c-erbB-2 expression above which tumours are classified as positive by flow cytometry has been determined by employment of positive cut-off threshold levels. c-erbB-2 expression by both flow cytometry and immunohistochemistry was studied using the monoclonal antibody NCL-CBII. The relationship of c-erbB-2 quantification by flow cytometry was then compared with ploidy, axillary node status, tumour size and grade. Increased c-erbB-2 expression was seen using flow cytometry. Correlation between immunohistochemistry and flow-cytometry methods just failed to reach significance (P = 0.06). Immunohistochemistry revealed a significant relationship between c-erbB-2 expression and aneuploidy (P = 0.04). Cytokeratin-positive cells from 110 samples obtained from patients with breast cancer were assayed for DNA content and c-erbB-2 expression by flow cytometry. No correlation was seen between these parameters upon application of Mann Whitney analysis. However, examination of fluorescence thresholds showed a positive correlation between grade and c-erbB-2 expression at a level of more than 3200 molecules (P < or = 0.03). At the level of 3600 molecules significance was increased (P = 0.004). These levels equated with between 15% and 19% of the samples being classified as c-erbB-2-positive. Application of these cut-off points showed no correlation between c-erbB-2 expression and ploidy, tumour size or axillary node status. Comparison of ploidy and grade showed a significant association (P = 0.0015), increased grade correlating with aneuploidy.
authors.affiliation: Department of Surgery, Medical School, University of Newcastle upon Tyne, UK.
authors.forename: I
authors.initials: I
authors.lastname: Brotherick
authors.forename: B K
authors.initials: BK
authors.lastname: Shenton
authors.forename: W K
authors.initials: WK
authors.lastname: Cowan
authors.forename: B
authors.initials: B
authors.lastname: Angus
authors.forename: C H
authors.initials: CH
authors.lastname: Horne
authors.forename: M J
authors.initials: MJ
authors.lastname: Higgs
authors.forename: T W
authors.initials: TW
authors.lastname: Lennard
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal; D001365:Axilla; D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000737:chemistry* / Q000235:genetics / Q000473:pathology; D002278:Carcinoma in Situ / Q000737:chemistry* / Q000235:genetics / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000737:chemistry* / Q000235:genetics / Q000473:pathology; D005260:Female; D005434:Flow Cytometry; D006367:HeLa Cells / Q000737:chemistry; D006801:Humans; D008207:Lymphatic Metastasis; D008214:Lymphocytes / Q000737:chemistry; D008875:Middle Aged; D011003:Ploidies; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis*
chemical_list: D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases