Anastrozole vs Tamoxifen

Over the period, several breast cancer treatments and medications came into existence. From surgical interventions to pharmaceutical approaches, every treatment has its individual preference. Lumpectomy, mastectomy, chemotherapy, and radiotherapy are some of the most common approaches for breast cancer.

Adjuvant therapy is also a part of cancer treatment, which involves hormone therapy, chemotherapy, radiation therapy, or any specific person-specific therapy. Adjuvant therapy helps kill any cancer cells that might be left post-surgical intervention. This therapy helps lower the chances of breast cancer to come back in the patient.

What is Anastrozole?

Anastrozole is a competitive aromatase inhibitor that helps prevent or treat breast cancer in its early stages. Most of the time, Anastrozole is effective for the treatment, but its preventive effects have recently been seen. Anastrozole can minimize the risk of developing breast cancer among women who are on the edge of developing it.

Advantages of Anastrozole:

The most significant advantages of Anastrozole are:

• Treatment of estrogen-positive breast cancer among women
• Prevention of development of breast cancer among postmenopausal women
• Slowing or reversal of growth of the breast cancer tissues in the body

Clinical trials and efficacy of Anastrozole:

According to a research study, Anastrozole effectively treats metastatic breast cancer (HR-positive cancer). This drug can also be used in combination with the fulvestrant.

As per the results of another study, a large group of cancer patients progressed with the help of anastrozole adjuvant therapy.

What is Tamoxifen?

Tamoxifen belongs to the group of drugs called SERM (selective estrogen receptor modulator). This drug is beneficial for various interventions or treatments of breast cancer among women.

The most significant advantages of Tamoxifen are:

• Reduction in risk of early-stage estrogen receptor-positive breast cancer and recurrence of the cancer
• Treatment of advanced-stage breast cancer among postmenopausal women
• Reduction in the incidence of cancer for people who are relatively at higher risk of developing it

Comparison of tamoxifen and anastrozole:

According to different clinical research and data, Tamoxifen and Anastrozole are effective as primary or adjuvant therapy for breast cancer. Regarding the side effects, both drugs were found responsible for classic side effects such as bleeding, vaginal discharge, hot flashes, endometrial cancer (in rare cases), and different thromboembolic events. However, Anastrozole is most associated with musculoskeletal disorders such as fractures and arthralgia.

The cost of the drugs and treatments depends on the patient’s condition and treatment area. However, most of the time, patients can afford the treatment cost.

As per the patient’s preference for the drug of choice, nastrozole is used in the early stages of the cancer. However, Tamoxifen has more accuracy in advanced cancer stages.

Conclusion:

As per the clinical trials and research, Anastrozole has more efficacy and superiority in comparison to Tamoxifen for estrogen-positive breast cancer. The effect of this drug was more potent and defensive for the prevention of contralateral breast cancer. However, future studies must focus on addressing the associated side effects of both treatments to maximize the good prognosis of the disease.

References:

1. Mehta, R. S., Barlow, W. E., Albain, K. S., Vandenberg, T. A., Dakhil, S. R., Tirumali, N. R., … & Hortobagyi, G. N. (2012). Combination anastrozole and fulvestrant in metastatic breast cancer. New England Journal of Medicine, 367(5), 435-444.
2. Partridge, A. H., LaFountain, A., Mayer, E., Taylor, B. S., Winer, E., & Asnis-Alibozek, A. (2008). Adherence to initial adjuvant anastrozole therapy among women with early-stage breast cancer. Journal of Clinical Oncology, 26(4), 556-562.
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6. Cuzick, J., Sestak, I., Baum, M., Buzdar, A., Howell, A., Dowsett, M., & Forbes, J. F. (2010). Effect of anastrozole and tamoxifen as adjuvant treatment for early-stage breast cancer: 10-year analysis of the ATAC trial. The lancet oncology, 11(12), 1135-1141.