Prognostic value of c-erbB2 overexpression in axillary lymph node positive breast cancer. Results from a randomized adjuvant treatment protocol.
BACKGROUND
This study was designed to evaluate the prognostic importance of c-erbB2 overexpression in a standardized cohort of patients with axillary lymph node positive breast cancer.


METHODS
Paraffin embedded primary breast cancers from 354 patients with axillary lymph node positive breast cancer, treated on a North Central Cancer Treatment Group adjuvant protocol, were studied immunohistochemically. c-erbB2 staining was classified as negative, weak (1+), moderate (2+), or strong (3+) and was assessed for effectiveness as a predictor of outcome in univariate and Cox model multivariate analyses.


RESULTS
Twenty percent of specimens exhibited moderate or strong c-erbB2 staining. The median disease free survival period of the strong staining group was 2.9 years, compared with 7.1 years for all other patients (P = 0.01). The median overall survival for the strong staining group was 5 years, compared with 12 years for all other patients (P = 0.03). A definite correlation was noted between degree of nodal involvement and the likelihood of strong c-erbB2 staining (P = 0.001). There was also a significant correlation between c-erbB2 staining and higher nuclear grade and estrogen receptor negativity. In a multivariate analysis, c-erbB2 staining was not a significant predictor of either disease free survival or overall survival.


CONCLUSIONS
According to this analysis, the strong correlation between c-erbB2 expression and degree of nodal involvement, higher grade disease, and estrogen receptor negativity suggests expression of this protooncogene product in a biologically more aggressive form of breast cancer. In a multivariate analysis, c-erbB2 expression was not an independent prognostic factor. Thus, c-erbB2 assessment did not appear to add significantly to the information provided by currently available standard disease parameters.
Department of Oncology, Mayo Clinic, Rochester, Minnesota 55905.
L C
LC
Hartmann
J N
JN
Ingle
L E
LE
Wold
G H
GH
Farr
J P
JP
Grill
J Q
JQ
Su
N J
NJ
Maihle
J E
JE
Krook
T E
TE
Witzig
P C
PC
Roche
D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics* / Q000473:pathology; D017024:Chemotherapy, Adjuvant; D002985:Clinical Protocols; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008207:Lymphatic Metastasis / Q000235:genetics*; D008875:Middle Aged; D015999:Multivariate Analysis; D017698:Postmenopause; D017697:Premenopause; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics*; D011960:Receptors, Estrogen / Q000032:analysis / Q000235:genetics; D015996:Survival Rate; D016896:Treatment Outcome
D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen