1- What is tamoxifen?
Tamoxifen is a drug taken as oral tablets. Used to treat breast cancer for males and females for more than 30 years. It acts by inhibiting the hormone estrogen, but does not inhibit it's synthesis from the ovaries or adrenal glands (estrogen is a hormone secreted normally in all females, it is considered a stimulant of cancer cells growth in females with genetic predisposition)
2- How is tamoxifen given?
Tamoxifen is a tablet taken orally with the food intake or on empty stomach with sips of water or juice, in any time of the day, but it must be taken at the same time everyday. And its very important to be taken according to the doctor's prescription.
3- What are the benefits of taking tamoxifen?
· It decrease the chance of recurrence of breast cancer, it also help in preventing new breast cancer from appearing
· It helps in delaying or stopping the proliferation of metastatic breast cancer cells in the body (in stage 4 of the disease)
· It helps in preventing breast cancer in patients with high risk of developing the disease
4- What do I have to do if I forgot to take the tamoxifen tablet?
if you forget, take the tablet as soon as possible within 12 hours. But if 12 hours passed, cancel this tablet and resume the medication the other day.
5- Is pregnancy possible during the tamoxifen therapy?
Yes, pregnancy is possible while taking tamoxifen, where as the drug is used sometimes in the treatment of infertility, but it can harm the embryo during pregnancy. It is better to coordinate with the treating oncologist to choose the best way of preventing pregnancy, and the use contraceptive pills must be avoided. It is also very important to inform your physician in case of pregnancy. Breast feeding must also be avoided during tamoxifen therapy.
6- Does temoxifen cause menopause (stopping of monthly menstruation)?
Tamoxifen does not call menopause unless the woman is close to her natural menopausal age, but it can cause irregularity
7- To whom tamoxifen is given?
· Tamoxifen is used to treat early stages of breast cancer as an adjuvant to the main medication to increase the chances of healing
· Used to treat the metastatic breast cancer (stage 4 of the disease)
· also used for the treatment of women found to have pre-cancer stage (ductal carcinoma in situ)
· used to prevent or reduce the risk of breast cancer in high-risk women
8- What is the mechanism of action of temoxafin?
Estrogen is a hormone (estrogen is a hormone secreted normally in all females, it is considered a stimulant of cancer cells growth in females with genetic predisposition).
Breast cancer is divided into two main classes.
· The first class is the breast cancer cells with estrogen receptors (known also as sensitive hormone) which means the cells possess the protein that will bind estrogen.
· The second class is breast cancer with no estrogen receptors (also known as insensitive hormone) which means this group do not have the protein that is stimulated by estrogen.
In the first class, the cancer cells usually need the estrogen to proliferate. tamoxifen binds to this receptor and prevent estrogen binding and therefore inhibiting the its action on the cells. So, the type of receptor should be determined before deciding the therapy.
Although the tamoxifen antagonize the effect of estrogen on breast cells, it function as estrogen agonist in other parts of the body and gives the same effects of estrogen. this means that women who use tamoxifen benefited from it as an alternative medication to estrogen in post menopausal symptoms, like osteoporosis
9- What is the time period when tamoxifen should be used to treat breast cancer?
Time period depends mainly on the goal of therapy, its as follows:
· Metastatic breast cancer (cancer has spread to other parts of body) they continue the therapy as long as there is response and the disease is controlled
· If it is used as an adjuvant to the main therapy, it is given for 5 years
· If the goal was to prevent or reduce the risk of having the disease in high-risk patients, then it is given for 10 years.
10-What are the side effects of tamoxifen that should be known?
There are known dangerous side effects:
· Blood thrombosis (clots)
· Stroke
· Uterine cancer
· Cataract
Other side effects:
Menopausal like symptoms like vaginal discharge, irregular menstruation, headache, nausea, vomiting, generalized weakness, dry and itchy vagina.
11- Does tamoxifen cause uterine cancer?
Tamoxifen increase the risk of uterine cancer. There are two types of uterine cancer:
· Endometrial carcinoma
· Uterine muscle cancer (leiomyosarcoma)
Studies proved that developing uterine cancer is about 2 in every 1000 women taking tamoxifen for 1 year compared to 1 woman in every 1000 not taking tamoxifen.
Most of the cases developing during tamoxifen therapy are diagnosed in early stages and usually is effectively treated.
The main symptoms of uterine cancer:
· Unusual uterine bleeding
· Pain in the lover abdomen of pelvis
It is preferred for all patients taking tamoxifen to be periodically examined by gynecologist
12-Does tamoxifen cause any other type of cancers?
It is not known that tamoxifen cause any other cancer apart from the one already mentioned (endometrial caner and leiomyosacroma)
13-Does tamoxifen cause any eye problem?
With the age progression of women they become more prone to deveop cataract, thus women taking tamoxifen have higher risk of cataract. But other ophthalmological problems like corneal injury, some retinal changed was observed with small number of patients
14-Does the benefits of tamoxifen over-weigh the risks?
tamoxifen benefits in the treatment of breast cancer is proved scientifically and far outweigh the potential risks. Therefore, the patient must discuss the benefits and risks with the treating physician
15-Is it possible for any woman to take tamoxifen to minimize or reduce the risk of breast cancer?
Taking tamoxifen is a personal decision, the patients should carefully consider and discuss with her treating physician benefits and side effects of tamoxifen
At this time there is no evidence that there is benefit in tamoxifen for women who do not have breast cancer or high risk for breast cancer
