title: Clinical value of enzyme immunoassay of epidermal growth factor receptor in human breast cancer.
abstract: Epidermal growth factor receptor (EGFr) levels were analyzed in 140 primary breast cancer specimens by immunohistochemical assay (ICA), competitive binding assay (BA), or enzyme immunoassay (EIA). Thirty-nine of 118 specimens (33.1%) were scored as positive by ICA, 30 of 116 (25.9%; cut-off level 10 fmol/mg protein) by BA, and 31 of 80 (38.9%: cut-off level 5 fmol/mg protein) by EIA. Agreement on EGFr status was 72.3% (68/94) between ICA and BA, 77.0% (57/74) between BA and EIA, and 73.8% (59/80) between EIA and ICA. These discrepancies are based on assay differences and the heterogeneous distribution of cancer cells within specimens. Regardless of the assay method used, EGFr status had a significantly negative correlation with estrogen receptor status. Although EGFr-ICA and BA status had no relationship with prognosis, patients with medium and high EGFr-EIA level tumors (over 5 fmol/mg protein) had shorter relapse-free periods than those with low level tumors. However, the prognostic value of positive EGFr-EIA status was weaker than that of c-erbB-2 overexpression.
authors.affiliation: Second Department of Surgery, Nagoya City University Medical School, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Iwase
authors.forename: S
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Itoh
authors.forename: T
authors.initials: T
authors.lastname: Kuzushima
authors.forename: H
authors.initials: H
authors.lastname: Yamashita
authors.forename: H
authors.initials: H
authors.lastname: Iwata
authors.forename: A
authors.initials: A
authors.lastname: Naito
authors.forename: T
authors.initials: T
authors.lastname: Yamashita
authors.forename: K
authors.initials: K
authors.lastname: Itoh
authors.forename: A
authors.initials: A
authors.lastname: Masaoka
mesh_terms: D000328:Adult; D000368:Aged; D001667:Binding, Competitive; D001943:Breast Neoplasms / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure*; D066246:ErbB Receptors / Q000032:analysis* / Q000378:metabolism / Q000502:physiology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011518:Proto-Oncogene Proteins / Q000032:analysis / Q000502:physiology; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis
chemical_list: D066246:ErbB Receptors; D011518:Proto-Oncogene Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone