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Hormone therapy for breast cancer
Last reviewed: 23.04.2024
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Hormonotherapy for the treatment of breast cancers has been used for more than a century. At the end of the XIX century, the first results of treatment of patients with breast cancer by the method of ovariectomy (removal of the ovaries) were published, which showed good efficacy.
After oncologists suggested various methods of hormonotherapy: radiation castration, androgen intake, adrenal removal, surgical destruction of the pituitary gland, the use of antiestrogens, antiprogestins, aromatase inhibitors.
Over time, effective methods of hormone therapy - radial, surgical, and medicinal.
To date, hormone therapy is an integral part of complex therapy at any stage of breast cancer.
There are two areas of this type of treatment for breast cancer: stopping (inhibiting) the production of estrogens and taking antiestrogenic drugs.
Treatment is chosen by a specialist, taking into account various factors - the age and condition of the patient, the stage of the disease, the concomitant diseases. Surgery for ovarian removal is prescribed only to women with preserved menstrual function or with early menopause, in postmenopausal women effective drugs that reduce the level of estrogen, in the reproductive age, use releasing hormones
Tumors of the breast are classified as hormone-dependent, but only about 40% of patients have a positive effect on hormone therapy.
It should be noted that some drugs can replace surgical treatment, for example, taking aromatase inhibitors allows you to avoid removing the adrenal glands, releasing hormones - removing the ovaries.
[The consequences of hormone therapy for breast cancer
Like any other treatment, hormone therapy for breast cancer has consequences, among which we can highlight weight gain, puffiness, early menopause, excessive sweating, and dryness of the vagina.
In addition, some patients note the oppression of mood, the development of depression.
Some drugs have severe side effects, for example, the widely used tamoxifen increases the risk of blood clots, can lead to uterine cancer, infertility.
Drugs that reduce the production of estrogen (aromatase inhibitors), which are prescribed during the postmenopause, provoke osteoporosis, increase the risk of blood clots, gastrointestinal diseases, increase cholesterol.
The effectiveness of treatment for hormone-dependent tumors is quite high. If progesterone and estrogen receptors are detected in cancer cells, hormone therapy will be effective by 70% if only one type of receptor is detected, by 33%.
In other types of tumors, the effectiveness of hormone therapy for breast cancer is only 10%.
Hormone therapy for breast cancer is an effective method of therapy for hormone-dependent breast tumors. This method is also called anti-estrogen and the main purpose of such treatment is to prevent the effect of the female hormone on cancer cells.
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Indication for hormone therapy
Hormone therapy for breast cancer is indicated in women with non-invasive forms of cancer (to prevent the recurrence of the disease or transition to an invasive cancer process), after surgery, radiation or chemotherapy to reduce the likelihood of recurrence, with large tumors (before surgery, therapy can reduce neoplasm and help the surgeon to reveal pathological tissues), with metastases (hormonotherapy allows to stop further metastasis), as well as with genetic predisposition.
Medications for hormone therapy
Hormonal therapy for breast cancer today takes place in two directions: treatment in view of the menstrual cycle and regardless of it.
With universal methods of hormone therapy independent of the menstrual cycle, antiestrogens and progestins are used.
The most common and investigated, for a long time used by oncologists, is an anti-estrogen remedy - tamoxifen. With prolonged use, the drug can increase the level of estrogen in the blood, increases the risk of developing hormone-dependent tumors in other organs, and also clinically proven the probability of thromboembolic complications and toxic effects on the liver.
Today, in most cases, tamoxifen is prescribed no longer than for 5 years.
No less popular drugs from this group are toremifene, raloxifene.
Separately, it is worth talking about fulvestrant, to which modern hormone therapy of breast cancer allocates a special place. The drug destroys the estrogen receptors of the tumor, so a number of specialists refer to it as "true antagonists."
Standard oncologists prescribe hormone therapy in one of three main schemes, which differ in the principle of action - a decrease in blood levels of estrogen, blocking estrogen receptors, a decrease in the synthesis of estrogen.
After the examination, the following treatment can be prescribed:
- selective modulators of estrogen receptors - therapy is aimed at disabling estrogen receptors (chemical substances exert a selective effect on the cells, giving an estrogen-like effect), the main drug of this direction is tamoxifen.
- Aromatase inhibitory drugs - used in the postmenopausal period, reduce the production of estrogen. In practice, oncologists use letrozole, anastorazole, exemestane.
- blocking and destruction of estrogen receptors (Fulvestrant, Faslodex).
Estrogen receptors are found on cancer cells and attract estrogen, which contributes to the further growth of the tumor. Depending on their level, the laboratory makes a conclusion about the hormone dependence of the tumor, after that, the doctor determines the treatment scheme to choose.
Antitumor drug Tamoxifen has an anti-estrogenic effect. After taking tamoxifen, it binds to estrogen receptors in organs susceptible to the development of hormone-dependent tumors and inhibits the growth of cancer cells (if the tumor develops due to ß-17 estrogen).
It is prescribed for men and women (mainly during menopause) with breast cancer, for ovarian cancer, endometrium, kidney, prostate, after operations to adjust the hormonal background.
Dosage is determined individually, taking into account the patient's condition.
When a breast cancer is usually prescribed 10 mg 1-2 times a day. If necessary, a specialist can increase the dosage to 30-40 mg per day.
Tamoxifen should be taken for a long time (from 2 months to 3 years) under the supervision of a doctor. The course of treatment is determined individually (usually the drug is stopped taking 1-2 months after regression).
Repeat the course after a 2-month break.
After removal of the breast to adjust the level of hormones prescribed 20 mg per day.
Taking the drug can cause nausea, vomiting, indigestion, lack of appetite, in some cases leads to excessive accumulation of fat in the liver, hepatitis. Possible depression, headaches, puffiness, allergic reactions, bone pain, fever. Long-term use can provoke retinal damage, cataract, corneal pathology.
Women can cause the growth of the endometrium, bleeding, suppression of menstruation, in men - impotence.
Toremifene by the principle of action is close to tamoxifen, the drug interferes with the production of estrogen in the body. It is prescribed in the postmenopausal period, from 60 to 240 mg every day for several years.
On the background of treatment, negative reactions of the organism may occur, in particular, dizziness, increased intraocular pressure and cataract development, myocardial infarction, acute blockage of blood vessels, decreased platelet count, allergic reactions, increased endometrial tissue, thrombosis, heat, sweating.
Toremifene has a toxic effect on the liver.
Simultaneous reception with drugs that reduce the excretion of calcium in the urine, increases the risk of hypercalcemia.
You can not simultaneously take Toremifene with drugs that extend the QT interval.
During the administration of rifampicin, phenobarbital, dexamethasone, phenytoin and other inducers of CYP3A4, an increase in the dosage of Torremifen may be required.
Treatment should be under the supervision of a doctor.
Raloxifene is a selective modulator of estrogen receptors. It is prescribed for breast cancers in the period of menopause to prevent the development of osteoporosis (decreased density and dysfunction of the bones).
The drug normalizes the level of calcium, reducing its excretion from the body by the kidneys.
Raloxifene should be taken for a long time (60 mg per day), usually in the elderly, the dosage is not adjusted.
Against the backdrop of treatment may appear cramps calf muscles, thromboembolism, swelling, a feeling of heat in the body. When there is uterine bleeding, you need to contact your doctor and go through an additional examination.
During treatment, you need to take calcium.
The anti- cancer drug Fulvestrant also suppresses estrogen receptors. The drug blocks the action of estrogens, while estrogen-like activity is not observed.
Data on the possible effect on the endometrium, endothelium during the postmenopause, bone tissue there.
In oncology it is used to treat breast cancer tumors in the form of injections, the recommended dose is 250 mg 1p per month.
During treatment, nausea, upsetting of the stool, loss of appetite, thromboembolism, allergic reactions, puffiness, back pain, discharge from the nipples, increased risk of urinary tract infection, bleeding.
Faslodex includes the same active substance that Fulvestrant has anti-estrogenic effect.
It is prescribed for advanced breast cancer during the postmenopausal period.
Use the drug in the form of injections (intramuscularly) once a month for 250 mg.
With a moderate expression of violations of the liver, dose adjustments are not required.
The safety of the drug in cases of impaired kidney function has not been tested.
Letrozole suppresses the synthesis of estrogens, has an antiestrogenic effect, selectively inhibits aromatase.
Standardly assigned 2.5 mg per day for 5 years. The drug should be taken every day, regardless of food intake.
Letrozole should be discontinued if the first signs of disease progression are manifested.
At the last stages, with metastasis, the drug intake is shown while tumor growth is observed.
With liver failure and elderly patients, dose adjustment is not required.
Data on simultaneous admission with other anti-cancer drugs are not available.
Caution is advised to prescribe letrozole with drugs that are metabolized by the isoenzymes CYP2A6 and CYP2C19.
Anastrozole refers to antagonists of estrogens, selectively suppresses aromatase.
It is indicated for the treatment of the initial stages of hormone-dependent breast tumors in postmenopausal women, as well as after treatment with tamoxifen.
The drug should be taken for 1 hour before meals (or 2-3 hours after).
Usually appointed at 1 mg per day, the duration of treatment is determined individually, taking into account the severity and form of the disease.
Do not take drugs with hormones at the same time as Anastrozole.
Against the background of treatment, bone density decreases.
Data on the effectiveness of complex treatment (anastrozole + chemotherapy) is not available.
The drug may cause severe dizziness, continuing headaches, drowsiness, depression, lack of appetite, vomiting, dry mouth, allergies, bronchitis, rhinitis, pharyngitis, chest pain, back pain, increased sweating, decreased joint mobility, swelling, alopecia, increase weight.
Simultaneous reception of tomoxifen and anastrozole is contraindicated.
Exmestan is indicated for the treatment and prevention of cancer or malignant lesions in the mammary gland, refers to estrogen antagonists.
Take Ezmestan after a meal of 25 mg per day, the duration of the reception - until the tumor progresses again.
It is not recommended to prescribe the drug to women in premenopausal endocrine status, as there is no data on the efficacy and safety of treatment in this group of patients. If there is a violation of the liver, dose adjustment is not required.
Prescribe Exmestan after determining the postmenopausal status of the patient.
Against the background of treatment, fatigue, dizziness, headaches, sleep disturbance, depression, vomiting, lack of appetite, stool disorders, allergies, excessive sweating, baldness, swelling may appear.
Preparations containing estrogens suppress the therapeutic effect of Ecstistan.