Download Hormone Therapy for Breast Cancer Treatment

FA C T S F O R L I F E
Hormone Therapy for Breast
Cancer Treatment
What are hormones?
Hormones are chemicals made in the body. They control
how cells and organs work. Two female hormones, estrogen
and progesterone, are made in the ovaries. They help
regulate a woman’s monthly period.
AIs include:
• Anastrozole (Arimidex)
• Letrozole (Femara)
• Exemestane (Aromasin)
Hormone therapy can lower the risk that breast cancer will:
• Recur (return) or metastasize (spread)
Hormones and breast cancer
• Occur in the other breast
Some breast cancer cells need hormones to grow.
If breast cancer cells need hormones to grow, they
will have many proteins called hormone receptors.
Tumors with many proteins are called hormone
receptor-positive tumors (HR+). Cells with few or
none of these proteins are called hormone receptornegative (HR-). Hormone receptor status is key in
planning breast cancer treatment. Breast cancers that
are HR+ can be treated with hormone therapy.
• Cause death
Hormone therapy
Hormone therapies slow or stop the growth of estrogen
receptor-positive (ER+) tumors. They prevent cancer cells
from getting the hormones they need to grow. They do
this in a few ways. Some hormone therapies attach to the
receptor in the cancer cell. It blocks estrogen from getting
to the receptor. This keeps the cancer cells from getting
the estrogen they need to grow. Tamoxifen is a drug that
works in this way. It is used to treat breast cancer in preand post-menopausal women. It is also used to treat breast
cancer in men.
Aromatase inhibitors (AIs) are another type of hormone
therapy. AIs lower the amount of estrogen in the body.
As a result, the cancer cells don’t get the hormones they
need to grow. They are used for postmenopausal women.
How is hormone therapy given?
Tamoxifen and AIs are pills. They are taken daily for at least
five years. Tamoxifen may be taken for a few years, then
followed with an AI. Or, one of the AIs may be taken alone
for five years. Women who complete the full course of
therapy have higher rates of survival. To get the full benefit,
they should be taken as prescribed for the full five years.
The benefit continues even after the drugs are stopped. New
studies show that taking tamoxifen for ten years instead of
five may offer more benefit. Talk to your doctor about the
risks and benefits of taking it for more than five years.
Ovarian suppression as hormone
therapy
While not standard treatment, ovarian suppression may be
used to lower hormone levels in the body. The ovaries can be
removed by surgery. Or, a drug that stops the ovaries from
making estrogen can be taken. These are options only for
premenopausal women. You may want to discuss this option
with your doctor.
Antidepressants
Some antidepressants disrupt the way tamoxifen works in
the body. Be sure to talk to your doctor if you take them.
You may need to change to a different one.
For more information, visit www.komen.org or call Susan G. Komen’s breast care helpline at
1-877 GO KOMEN (1-877-465-6636) Monday through Friday, 9 AM to 10 PM ET.
Side effects of tamoxifen and aromatase
inhibitors
Both tamoxifen and AIs can cause menopausal symptoms
like hot flashes. Each has different risks. The three AI
drugs have similar side effects. However, you may prefer
one over another.
Aromatase
Inhibitors
Tamoxifen
Common
side effects
•H
ot flashes and
night sweats
• Vaginal discharge
• Hot flashes and
night sweats
• Joint and muscle pain
• Loss of bone mineral
Uncommon
or rare
health risks)
• Fatigue
• Nausea
• Loss of sex drive
• Vaginal bleeding
• Vaginal dryness
or itching
Very rare:
•B
lood clots in the large
veins or lungs
• Cataracts
•C
ancer of the uterus
or endometrium (lining
of the uterus)
• Stroke
• Bone fractures
• Dizziness
• Fatigue
• Hair thinning
• Headache
• Heart problems
• Increased blood
pressure
• Increased cholesterol
• Nausea
• Osteoporosis
• Vaginal dryness
or itching
Hormone therapy for metastatic breast cancer
For women with ER+ metastatic breast cancer, hormone
therapy is often the first treatment. The drug choice
depends on past hormone therapy treatments. The table
below shows some hormone therapy drugs used to treat
metastatic breast cancer. Research continues on others
that may be helpful in the future.
Drug
(Brand name)
Used to treat estrogen
receptor-positive
breast cancers in
women who are:
Hormone therapy versus
menopausal hormone therapy
Hormone therapy for breast cancer treatment is
different than menopausal hormone therapy (MHT).
Hormone therapies used in breast cancer treatment
block hormone actions or lower hormone levels in
the body. So, although these drugs are called hormone
therapies, they act as “anti-hormone” therapies. By
contrast, MHT is meant to increase hormone levels
in the body to treat menopausal symptoms.
MHT increases the risk of breast cancer. It is
recommended at the lowest dose for short-term
use to ease these symptoms. MHT may be
called postmenopausal hormones or hormone
replacement therapy.
Cost
Tamoxifen and all three AIs come in generic form. These
are less costly than the name brands. Medicare and many
insurance providers offer prescription drug plans. One may
be included in your policy. Or, you may be able to buy an
extra plan for prescriptions. You may qualify for programs
that help with drug costs or offer them for free. If you need
help paying for medications, contact our breast care helpline
for information at 1-877 GO KOMEN (1-877-465-6636)
Monday through Friday, 9 AM to 10 PM ET.
Injection
or pill?
Tamoxifen
(Nolvadex)
Premenopausal or
postmenopausal
Pill
Anastrozole
(Arimidex)
Postmenopausal
Pill
Exemestane
(Aromasin)
Postmenopausal
Pill
Fulvesterant
(Faslodex)
Postmenopausal
Injection
Letrozole (Femara)
Postmenopausal
Pill
Goserelin (Zoladex)
Premenopausal
Injection
Related fact sheets in this series:
• Clinical Trials
• How Hormones Affect Breast Cancer
• Making Treatment Decisions
• Research on Breast Cancer Treatment
• Treatment Choices — An Overview
Susan G. Komen® is not a health care provider and does not give medical advice. The information provided in this material is not meant to be used for self-diagnosis or to replace the
services of a medical professional.
The Running Ribbon is a registered trademark of Susan G. Komen®. ©2015 Susan G. Komen® Item No. KOMEED023000 5/15