Aromatase inhibitors are substances that inhibit the production of estrogen in women who have undergone menopause. Aromatase inhibitors block the enzyme aromatase, which converts androgen hormone into small quantities of estrogen in the body. This implies that less amount of estrogen is available in the postmenopausal females to stimulate the growth of hormone positive cells of breast cancer. Being a drug to regulate your hormones, side effects of aromatase inhibitors come along with benefits. 

What Are Aromatase Inhibitors?

Aromatase inhibitors are a type of new drugs that are used in the treatment of breast cancer in some cases or to help prevent the recurrence of breast cancer post initial surgery. The drugs included in this class are as follows:

• Exemestane (Aromasin®)
• Letrozole (Femara®)
• Anastrozole (Arimidex®)

The working of aromatase inhibitors is different from the working of tamoxifen and raloxifene. Aromatase inhibitors do not work by blocking the estrogen receptors; instead they work by inhibiting a key enzyme aromatase, which converts other hormones into estrogen. This helps in reducing the levels of estrogen in the body, thereby preventing the growth of estrogen receptor-positive breast cancer cells.

What Are the Benefits of Aromatase Inhibitors?

Numerous studies have been done to compare the effects of aromatase inhibitors and tamoxifen in the treatment of early-stage HR+ breast cancer in postmenopausal females. On the basis of results of these studies it has been recommended by most of the physicians that after initial treatment for breast cancer (surgery followed by chemotherapy and radiation therapy):

• Aromatase inhibitors are the best form of hormonal therapy to treat early-stage, HR+ breast cancer as they have more benefits and lesser side effects in comparison to tamoxifen therapy.
• Giving aromatase inhibitors after 2-3 years of tamoxifen therapy is more beneficial than taking tamoxifen for 5 years.
• Taking aromatase inhibitors for a period of 5 years after the completion of 5 years of tamoxifen therapy reduces the risk of recurrence in comparison to taking no treatment after tamoxifen therapy.

What Are the Side Effects Aromatase Inhibitors?

Fewer side effects are produced from taking aromatase inhibitors in comparison to taking tamoxifen, which increases the risk of stroke, blood clots and endometrial cancer.

The commonest side effect of taking an aromatase inhibitor is pain in joints or stiffness in joints, which can be quite troubling. Aromatase inhibitors are also associated with causing increased heart problems, increased bone loss leading to osteoporosis and more incidences of fractures in comparison to tamoxifen. If you are considering therapy with aromatase inhibitors, you can ask your doctor to perform a bone densitometry to determine if you will require a bone strengthening medicine along with the aromatase inhibitor.

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Aromatase Inhibitors & Breast Cancer Therapy: