title: Prognostic significance of c-erb B-2 protein status using an enzyme immunoassay in breast cancer.
abstract: Background. The prognostic significance of c-erb B-2 in breast cancer remains controversial. The aim of this study was to determine the practical prognostic significance of c-erb B-2 protein status in breast cancer extracts, using an enzyme immunoassay. Methods. An enzyme immunoassay was used to measure levels of c-erb B-2 protein prospectively in 360 patients with breast cancer, using cytosol fractions prepared for steroid receptor assay. The status of c-erb B-2 protein was assessed using a cut-off value for positivity of 18 ng/mg protein. Univariate and multivariate analyses were performed. To evaluate the prognostic significance of c-erb B-2 protein status. Results. Levels of c-erb B-2 protein in tumor tissue extract ranged from 0 to 213.0 ng/mg protein (mean, 15.5 ng/mg protein). In 52 tumors (14.4 %) more than 18.0 ng/mg protein was detected, and these tumors were regarded as c-erb B-2 protein-positive. Correlations were found between c-erb B-2 protein positivity and large tumor size (>3 cm; P = 0.0095), higher histological grade (P < 0.0001), estrogen receptor negativity (P < 0.0001), and progesterone receptor negativity (P < 0.0001). There was also a marginally significant correlation between c-erb B-2 protein positivity and lymph node positivity. Multivariate analysis showed that c-erb B-2 protein status was a significant independent prognostic factor for disease-free survival, being strongly significant in patients with positive lymph nodes. Conclusion. c-erb B-2-positive breast cancers are biologically more aggressive and c-erb B-2 protein status could be a candidate as a prognostic factor for patients with breast cancer, being particularly valuable in patients with positive lymph nodes.
authors.affiliation: Department of Surgery, Osaka National Hospital, 2-1-14 Hoenzaka, Chuo-ku, Osaka 540-0006, Japan Tel. +81-6-6942-1331; Fax +81-6-6946-5660 e-mail: shin@onh.go.jp, , , , , , JP.
authors.forename: E
authors.initials: E
authors.lastname: Shin
authors.forename: Y
authors.initials: Y
authors.lastname: Takatsuka
authors.forename: I
authors.initials: I
authors.lastname: Nishisho
authors.forename: K
authors.initials: K
authors.lastname: Fujitani
authors.forename: H
authors.initials: H
authors.lastname: Mishima
authors.forename: T
authors.initials: T
authors.lastname: Sawamura
authors.forename: Y
authors.initials: Y
authors.lastname: Hasuike
authors.forename: K
authors.initials: K
authors.lastname: Kobayashi
authors.forename: T
authors.initials: T
authors.lastname: Tsujinaka
authors.forename: N
authors.initials: N
authors.lastname: Kikkawa