Final answer:
Tamoxifen is the first-line treatment for premenopausal breast cancer after surgical intervention, especially for tumors that are estrogen receptor-positive. Aromatase inhibitors are more commonly used in postmenopausal women. The application of chemotherapy and radiation therapy is determined by the specific characteristics of the cancer.
Step-by-step explanation:
The first-line treatment for premenopausal breast cancer after surgical treatment is generally tamoxifen. Tamoxifen is a type of hormonal therapy that works by interfering with the activity of estrogen, which can stimulate the growth of breast cancer cells. It is particularly indicated for premenopausal women who have estrogen receptor-positive breast cancer. Aromatase inhibitors are generally used for postmenopausal women, as they work by decreasing the amount of estrogen produced by the body. Other treatments such as chemotherapy and radiation therapy may be used depending on individual factors such as the size and grade of the tumor, lymph node involvement, and whether the cancer has spread.