Association between tumour characteristics and HER-2eu by immunohistochemistry in 1362 women with primary operable breast cancer.

摘要

AIMS: To investigate the association between tumour characteristics and HER-2eu by immunohistochemistry in primary operable breast cancer. METHODS: The association between HER-2eu and other clinicopathological factors was evaluated in 1362 consecutive patients with primary breast cancer treated between 2000 and July 2003 in one centre. Microscopic tumour size, tumour grade, lymph node status, patient's age, oestrogen receptor (ER), progesterone receptor (PR), and joint ER/PR status were evaluated, using the chi(2) test for univariate analysis and logistic regression for multivariate analysis. The hormone receptors and HER-2eu were studied immunohistochemically. Using the HER-2eu DAKO scoring system, scores of 0, 1+, or 2+ were defined as negative and 3+ as positive. Data for DAKO scores 2+/3+ versus 0/1+ are also presented. RESULTS: Hormone receptor negative breast cancers were more often HER-2eu positive than hormone receptor positive cancers, both for ER (28.7% v 6.8%) and PR (19.9% v 5.9%). In multivariate analysis, both ER, PR, and tumour grade were independently associated with HER-2eu. In ER(+) tumours, HER-2eu overexpression was significantly lower in PR(+) than in PR(-) cases (11.5% v 5.4%). HER-2eu overexpression (2.7%) was lowest in the large subgroup of ER(+)PR(+) tumours with low tumour grade (grade 1-2), comprising 46.1% of all patients. CONCLUSIONS: ER, PR, and tumour grade are independent predictors for HER-2eu overexpression in women with primary operable breast cancer. ER and PR are negatively associated with HER-2eu, whereas tumour grade is positively associated with HER-2eu. In women with ER(+) tumours, PR status also affects the likelihood of HER-2eu expression.