title: Immunohistochemiluminescence detection: a quantitative tool in breast cancer HER-2 status evaluation.
abstract: Her-2 status evaluation in breast cancer has prognostic and treatment response value but its interobserver variation among pathologists is a problem since it is not quantitatively assayed. This study presents an immunohistochemiluminescence method to quantify Her-2 in breast cancer. Anti-Her-2 antibody was conjugated to acridinium ester (AE) and used to evaluate/quantify Her-2 status in breast Invasive Ductal Carcinoma (IDC, n=50) comparing with traditional immunohistochemistry. Anti-HER-2-AE results were expressed in Relative Lights Units (RLU) and showed to be able to distinguish and quantify the differences between the three groups of Her-2 status. 3+ Her-2 status presented the highest RLU (246,982 × 10(3) ± 2.061 × 10(3)) compared to 2+ (76,146 × 10(3) ± 0.290 × 10(3)), negative (27,415 × 10(3) ± 1.445 × 10(3)) and normal tissues (27,064 × 10(3) ± 2.060). Status differences were significant between 3+ and 2+ (p=0.0025); 2+ and negative (p=0.0003), and +3 and +1 (p=0.0001) beside this, normal breast control RLU was 27,064 × 10(3) ± 2,060 × 10(3), similar to negative cases. Results showed that anti-HER-2-AE conjugate was effective in breast tumors Her-2 status evaluation, allowing its quantitative establishment to consequently decrease the subjectivity in prognostic and predictive information intrinsic to this test.
authors.affiliation: Laboratório de Imunopatologia Keizo Asami (LIKA), Universidade Federal de Pernambuco (UFPE), Recife, Brazil.
authors.forename: Moacyr Jesus Barreto
authors.initials: MJ
authors.lastname: de Melo Rêgo
authors.forename: Marina Ferraz
authors.initials: MF
authors.lastname: Cordeiro
authors.forename: Carmelita de Lima Bezerra
authors.initials: Cde L
authors.lastname: Cavalcanti
authors.forename: Luiz Bezerra
authors.initials: LB
authors.lastname: de Carvalho Junior
authors.forename: Eduardo Isidoro Carneiro
authors.initials: EI
authors.lastname: Beltrão
mesh_terms: D001943:Breast Neoplasms / Q000175:diagnosis*; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D049449:Luminescence; D008163:Luminescent Measurements / Q000379:methods*; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis*
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human