Reproductive Factors, Steroid Receptor Status, and Tumour Markers of HER2-Positive Breast Cancer in Northern China

Background: Although China has a breast cancer incidence that surpasses all other cancer registries, there have been few reports to evaluate the relationships of reproductive history, steroid receptor status, and tumour markers with HER2 status of breast cancer. Patients and Methods: This project included 274 primary invasive ductal breast cancer patients. Information concerning the reproductive factors and tumour characteristics of the patients had previously been collected. HER2 and steroid receptor status were detected in tumour tissues. Serum CEA, CA15-3, and CA125 levels were analyzed for all patients. Results: Younger age at menarche was observed in patients with HER2-positive than in those with HER2negative status (p = 0.03). Statistically significant differences were found between the HER2-positive group and HER2-negative group for estrogen receptor (ER) and progesterone receptor (PR) status (p Conclusion: We confirm that age at menarche may plausibly be differentially correlated with the risk of HER2-positive invasive ductal breast cancer because it is presumed to impact exposure to endogenous sex hormones. HER2 is inversely related to ER and PR in invasive ductal breast cancer patients of Northern China.