Publication Year: 2000 Visited: 59

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Overexpression of HER-2/neu (c-erb B-2) Oncogene is Positively Correlated with an Extensive Intraductal Carcinoma (EIC) in Early Stage Breast Cancer. Olivia Bennett, Tara Sigler, Michael A Hunter, Zelig Leyser, Eric W Taylor, Evergreen Medical Ctr, Kirkland, WA.

Pathologic specimens of 321 primary pathologic T1 and T2 breast cancers obtained by breast excisional biopsy or mastectomy were prospectively examined. The relationship between overexpression of HER-2/neu (c-erb B-2), p53, lymphvascular invasion, lymph node regional metastasis, histologic grade, nuclear grade, ER, PgR, and the presence of extensive intraductal carcinoma (EIC, Harvard definition) was assessed. For the HER-2/neu analysis, deparaffinized sections of formalin-fixed tissue were incubated with polyclonal antibodies (along with appropriate controls) to the oncogene. Localization was done via a modified avidin biotin immunoperoxidase technique, with pretreatment (heat-induced epitope retrieval) according to protocols optimized for the antibody (PhenoPath Laboratories, Seattle, WA). Chi-square and logistic likelihood ratio tests were conducted to evaluate significant differences. There was no correlation between c-erb B-2 overexpression and any of the pathologic features examined, with the exception of a positive correlation with extensive intraductal carcinoma (p<0.01). Given that the presence of EIC has been linked with a higher rate of local failure following breast-conserving surgery and radiation therapy with non-negative margins, perhaps the relationship described by other investigators between c-erb B-2 and local failure is due to a higher likelihood of the presence of an EIC.