الفهرس 
Microscopic anatomy of the breastOnly 14 pages are availabe for public view
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Abstract
Breast cancer is the most common malignancy diagnosed among women worldwide, and it is the second leading cause of cancer mortality. One of the hallmarks of the disease is the expression of estrogen receptor (ER) and progesterone receptor (PR), and this expression ultimately drives prognosis and treatment approaches. ER and PR expression varies in relation to different clinicopathologic features of breast carcinomas including patient age, menopausal status, tumor size, histological type and grade of breast carcinoma, lymph node metastasis and vascular lymphatic emboli, and HER-2/neu expression. Higher incidence of ER and PR expression was reported with advancing age. However, no statistically significant data were obtained. On the other hand, the expression values of ER and PR were higher in postmenopausal than in premenopausal females. As regard tumor size, some investigators found that tumors expressing ER and or PR tend to be smaller than tumors not expressing ER or PR. However, none of these differences reached a level of statistical significance. On the other hand, other investigators found no correlation between tumor size and ER and PR expression. ER and PR expression was found to be higher in low grade tumors than in high grade tumors. Also tumors without lymph node metastasis or vascular lymphatic emboli tend to express ER and PR more than tumors with lymph node metastasis and vascular lymphatic emboli. HER-2/neu overexpression is inversely correlated with the expression of ER and PR and is associated with increased resistance to hormonal therapy of breast cancer. Numerous studies have demonstrated differences in hormone receptor status by race and ethnicity.