Anastrozole

Definition

Anastrozole is a nonsteroidal aromatase inhibitor used in the treatment of hormone-receptor positive breast cancer in postmenopausal women. It works by blocking the aromatase enzyme, which is responsible for the conversion of androgens to estrogens, thereby reducing estrogen levels and slowing the growth of estrogen-dependent tumors.

5 Must Know Facts For Your Next Test

1. Anastrozole is approved for the adjuvant treatment of hormone receptor-positive early-stage breast cancer in postmenopausal women, as well as for the treatment of advanced or metastatic breast cancer in postmenopausal women.
2. Anastrozole is generally well-tolerated, with common side effects including hot flashes, joint pain, and fatigue.
3. Anastrozole is considered more potent and selective than the older aromatase inhibitor, tamoxifen, in reducing estrogen levels.
4. Anastrozole has been shown to improve disease-free survival and reduce the risk of recurrence in postmenopausal women with early-stage, hormone receptor-positive breast cancer.
5. Adherence to anastrozole therapy is crucial, as discontinuation or poor adherence can negatively impact treatment outcomes.

Review Questions

• Explain the mechanism of action of anastrozole in the context of hormonal therapy for breast cancer.
  • Anastrozole is a nonsteroidal aromatase inhibitor, which means it works by blocking the aromatase enzyme. This enzyme is responsible for the conversion of androgens, such as testosterone, into estrogens, such as estradiol. By inhibiting aromatase, anastrozole reduces the overall levels of estrogen in the body. This is particularly important in the treatment of estrogen receptor-positive (ER+) breast cancer, where the growth and proliferation of the cancer cells is stimulated by estrogen. By lowering estrogen levels, anastrozole can slow the progression of ER+ breast cancer in postmenopausal women.
• Describe the clinical use of anastrozole in the management of breast cancer, including the specific patient population and the benefits of therapy.
  • Anastrozole is primarily used in the adjuvant (after surgery) treatment of hormone receptor-positive, early-stage breast cancer in postmenopausal women. It has been shown to improve disease-free survival and reduce the risk of recurrence in this patient population. Anastrozole is considered more potent and selective than the older aromatase inhibitor, tamoxifen, in reducing estrogen levels. By effectively lowering estrogen levels, anastrozole can help slow the growth and spread of estrogen-dependent breast tumors, leading to better clinical outcomes for postmenopausal women with ER+ breast cancer.
• Analyze the importance of adherence to anastrozole therapy and the potential consequences of poor adherence or discontinuation of treatment.
  • Adherence to anastrozole therapy is crucial for the successful management of hormone receptor-positive breast cancer in postmenopausal women. Discontinuation or poor adherence to anastrozole can negatively impact treatment outcomes, as the drug's effectiveness relies on maintaining consistent and effective inhibition of the aromatase enzyme over an extended period of time. Patients who fail to adhere to the prescribed dosing regimen or who prematurely discontinue anastrozole therapy may be at a higher risk of cancer recurrence or progression, as the estrogen-lowering effects of the drug will be compromised. Therefore, it is essential for healthcare providers to emphasize the importance of adherence and to closely monitor patients to ensure they are able to tolerate and continue the anastrozole treatment as prescribed.

Related terms

Aromatase: An enzyme responsible for the conversion of androgens (such as testosterone) to estrogens (such as estradiol) in various tissues, including the breast.

Estrogen Receptor-Positive (ER+) Breast Cancer: A type of breast cancer in which the cancer cells have receptors for the hormone estrogen, and the growth and proliferation of these cancer cells is stimulated by estrogen.

Postmenopausal: Referring to the period in a woman's life after menopause, when the ovaries have stopped producing significant amounts of estrogen.