Though the incidence of serious conditions like cardiovascular disease, osteoporosis and cancer increase after menopause, some of these changes may not be related to decreased hormone levels.
MENOPAUSE does not increase the risk of cancer. However, the risk of cancer increases with increasing age. Hence, women who reach menopause are naturally more likely to get cancer simply because they are older.
Furthermore, some treatments for cancer, like surgery, chemotherapy or hormonal therapy, lead to cessation of ovarian function, resulting in menopause and its symptoms.
There are three types of cancer treatments that result in premature menopause.
The surgical removal of the ovaries (oophorectomy) in the treatment or prevention of ovarian, uterine and vaginal cancers, results in immediate onset of menopause because the primary source of the female hormones is removed.
Radiotherapy to the pelvis, where the ovaries are located, or chemotherapy, can result in premature menopause. Sometimes, the periods return in younger women after completion of the treatment. However, this is less likely to occur in women who are 40 years and above.
Some breast cancers use the oestrogen and/or progesterone produced by the body to grow. Such breast cancers are diagnosed by positive oestrogen and/or progesterone receptor findings. Hormonal (or endocrine) therapy is used to treat such breast cancers.
The medicines include anti-oestrogens like anastrozole, letrozole and exemestane, as well as tamoxifen. These medicines are also used to reduce the likelihood of the breast cancer returning after the completion of treatment.
Medicines like tamoxifen and raloxifene, are also used to reduce the likelihood of breast cancer occurring in women who are at increased risk.
The most frequent types of cancer that affect Malaysian women are breast (31.0%), cervix (12.9%), colon (6.0%), endometrium (4.3%), rectum (4.1%), and ovary (4.1%).
Women who reach menopause after the age of 55 years are at an increased risk of ovarian, breast and uterine cancers.
The risk is greater if their periods started before the age of 12. This is because there is increased exposure to more oestrogen, and increased ovulation. An increased exposure to oestrogen increases the risk of uterine and breast cancers, and more ovulations increases the risk of ovarian cancer.
Breast cancer is the most common cancer. It is the most feared by women and is frequently the focus of the media, so much so that many women think it is very common.
In fact, its incidence is much less than cardiovascular disease or osteoporosis. When detected and treated early, it is very amenable to treatment. Death rates have declined in recent years. The five-year survival rate for localised breast cancer is more than 90%.
There are several factors that increase the risk of breast cancer. The risk increases with age, reaching about 10% by 80 years of age. A woman’s risk is increased if there is a family history of ovarian cancer. The risk is also increased in women who had their first period below 12 years of age; late age of menopause; or have never been pregnant.
Women who have mutations of the BRCA1/BRCA2 genes, or a breast biopsy finding of atypical hyperplasia, are also at increased risk.
Obesity, alcohol consumption and a sedentary lifestyle are also risk factors.
Long term (more than five years) hormone therapy (HT) has been reported to be associated with a slightly increased risk of breast cancer.
Cervical cancer is very treatable if detected early, with five-year survival rates of more than 90%. It is caused by the human papillomavirus (HPV) infection, which is acquired through sexual intercourse.
There are more than 100 HPV types, of which 13 are high-risk types that cause cervical cancer.
The risk of cervical cancer increases with early sexual intercourse, multiple partners, smoking, other sexually transmitted infections, and HIV infection. Other risk factors are smoking and use of the combined oral contraceptive pill.
Neither the menopause nor the use of HT increases the risk of cervical cancer.
Endometrial (uterine) cancer is very treatable if detected early, with five-year survival rates of 95%. The risk of endometrial cancer is increased with increased exposure to oestrogen, i.e. in women whose first period started at an early age; late menopause; never been pregnant; or in rare oestrogen-producing tumours.
The risk is also increased in women who are obese; have polycystic ovarian syndrome; have diabetes or high blood pressure (hypertension); or those who have endometrial hyperplasia.
The use of oestrogen without progestogen or tamoxifen also increases the risk.
Previous pregnancy and the use of the birth control pill appear to provide some protection against endometrial cancer.
Ovarian cancer is not common, yet it causes more deaths than any other cancer of the reproductive organs, mainly because it usually presents at an advanced and less curable stage.
One of the main reasons for its late detection is the absence of symptoms in the early stages. If detected and treated early, five-year survival rates can exceed 90%.
The risk of ovarian cancer increases with age; late menopause; in women who have never been pregnant; those with a family history of breast or ovarian cancer; and those who are obese.
About one in 20 cases is due to faulty genes that increase the risk of breast and ovarian cancer.
Lung cancer is a leading cause of cancer death in women in many developed countries. The increase parallels the increasing number of women who smoke cigarettes.
As such, it can be expected to pose a problem for Malaysian women in future years. About nine in 10 lung cancers are caused by smoking. Exposure to secondhand smoke, radioactive materials, arsenic, nickel, chromium and air pollution, are also risk factors.
Colorectal cancer is not associated with menopause, but with increasing age, a family history of the cancer, colorectal polyps, inflammatory bowel disease, physical inactivity and smoking.
Most cancers can be successfully treated today. The most important factor in treatment success is early detection. Regular check-ups and seeking early medical attention is advisable, not only for menopausal women, but for all elderly women.
Dr Milton Lum is a member of the board of Medical Defence Malaysia. This article is not intended to replace, dictate or define evaluation by a qualified doctor. The views expressed do not represent that of any organisation the writer is associated with. For further information, e-mail firstname.lastname@example.org.