What are the common causes of ovarian cancer?
A risk factor is a cause or a factor that can increase or decrease your chances of getting a specific disease. In the case of ovarian cancer and other types of cancers, some of these risk factors can be either controllable or uncontrollable. This article discusses the causes of ovarian cancer.
Controllable risk factors are those that you can change. For example, if you are a smoker, you can cut down or completely stop smoking to reduce your exposure to carcinogens and to lower the risk of getting cancer. Uncontrollable factors are those that you have no control over, such as your age, genetic history, or family history of cancer.
The various risk factors for ovarian cancer are listed below:
Age
Age plays a primal role when it comes to the risk of developing ovarian cancer. The risk of ovarian cancer increases with increasing age. It can occur at any age, although diagnosing ovarian cancer in women below the age of 40 has become quite rare.
Reproductive factors:
Reproductive factors are associated with the development of ovarian cancers. Early menarche and late menopause increase the risk of ovarian cancer. Infertility also increases risk. Oral contraceptive pills and women with multiple pregnancies have a lower risk of developing ovarian cancer.
Hormonal Factors:
Polycystic ovarian disease (PCOD) appears to have an increased risk of developing ovarian cancer. Treatment for infertility does not appear to have increased risk. Studies show that postmenopausal hormone therapy increases risk. The use of oral contraceptive pills decreases the risk of ovarian cancer.
Genetic Factors:
Several ovarian cancer susceptibility genes have been identified. These genes primarily involve BRCA1 and BRCA2. Genetic mutations make up to a quarter of ovarian cancers.
Women with BRCA gene mutations have an increased risk of developing breast and ovarian cancer. The lifetime risk of ovarian cancer in BRCA1 mutation patients is 35 to 46 %, and for BRCA2 mutation is 13 to 23 %.
Lynch syndrome is associated with several cancers like colon cancer, endometrial cancer, ovarian cancer, urogenital, and other intestinal cancers. The lifetime risk of ovarian cancer in these patients is 3 to 14 %.
Family history
Family history plays a vital role in developing ovarian cancer. Women with a 1st-degree relative have more than the twofold increased risk of developing ovarian cancer.
Hormone replacement therapy
For most women going through menopause, doctors prescribe hormone replacement therapies in order to alleviate the symptoms {insert article hyperlink here} that comes with menopause such as dryness, hot flushes, and night sweats that usually occur when the body gets adjusted to the decreasing levels of estrogen.
Hormone replacement therapy usually includes treatment with estrogen alone. This is most commonly seen in the case of women with a hysterectomy. However, doctors recommend women without a hysterectomy a combination of progesterone and estrogen.
Women who receive hormone therapy are at a higher risk of developing ovarian cancer, according to some studies.
Environmental factors:
Cigarette smoking, current or past, appears to increase the risk of ovarian cancer, especially mucinous type of ovarian cancer.
There is no clear relationship between physical activity and ovarian cancer risk. However, there is a modest decrease in risk with high physical activity.
Obesity increases the risk of ovarian cancer.
How to reduce the risk of developing ovarian cancer?
Although doctors agree that there is no definite way to prevent ovarian cancer completely, control or reduction of risk of developing the disease is possible. Some of these methods include:
Oral contraceptives
Studies have shown that women who have used oral contraceptives for five or more years are at a 20% lower risk of developing ovarian cancer, as compared to women who have never used oral contraceptives before.
Pregnancy and breastfeeding
Numerous studies have shown that pregnancy and breastfeeding can significantly reduce the risk of developing ovarian cancer because women ovulate less frequently when they are either pregnant or breastfeeding. Multiple pregnancies or a full-term pregnancy before the age of 26, decrease the risk of developing ovarian cancer. Breastfeeding for a cumulative duration of more than 12 months reduces the risk of ovarian cancer.
Removal of ovaries and fallopian tubes (For BRCA1 positive women)- Salpingo-oophorectomy:
A surgery known as prophylactic bilateral salpingo-oophorectomy can significantly reduce the risk of developing ovarian cancer. This procedure includes the surgical removal of the ovaries and the fallopian tubes. Studies have shown that women with a confirmed positive BRCA1 gene mutation can reduce their ovarian cancer risk with this procedure.
Hysterectomy and tubal ligation
Hysterectomy (removal of the uterus) without oophorectomy (removal of ovaries) decreases the risk of developing ovarian cancer. By going through a tubal ligation procedure (which is the tying of the fallopian tubes), the risk reduces further.