Ovarian cysts are extremely common. But that doesn't make having one any less unsettling — many women worry that the presence of one or more means you have ovarian cancer or are more likely to get the disease.
"An ovarian cyst is not the same thing as ovarian cancer," says Dr. Aparna Kamat, a gynecologic oncologist at Houston Methodist. "Both develop in the ovaries, but there are significant differences between what they consist of, their causes and their treatments."
Most ovarian cysts come and go on their own — you may not even know you have one. In rare cases, an ovarian cyst can become cancerous. But while having a cyst does not mean you have cancer, it's important to understand these formations, their symptoms and when to talk with a doctor about them.
What are ovarian cysts?
An ovarian cyst is a sac that forms on or inside the ovary. It can be filled with fluid or a semisolid material.
Most ovarian cysts form due to a woman's menstrual cycle. These are called simple cysts, or functional cysts. Your ovaries grow small formations called follicles each month that produce hormones and break open to release an egg when you ovulate. If that follicle keeps growing, it's called a functional (or simple) cyst.
Functional cysts are usually harmless, often don't cause symptoms and go away on their own within a couple menstrual cycles. There are two types of functional cysts:
- Follicular cysts begin when the follicle doesn't rupture or release the egg.
- Corpus luteum cysts form when the opening where the egg came from becomes blocked and fluid builds up inside.
Complex cysts are not related to menstrual cycles and are more likely to cause complications or become cancerous, although this is very rare. There are several types of complex cysts:
- Cystadenomas form on the surface of your ovary and are filled with watery or mucous material.
- Dermoid cysts, also known as teratomas, often form before a person is born. These cysts can contain tissue such as hair, teeth or skin.
- Endometriomas are filled with menstrual blood and usually indicate a woman has endometriosis, a condition that causes cells similar to those that line the inside of the uterus to grow outside the uterus. (Related: The Symptoms of Endometriosis & When to Seek Care)
- Ovarian cancer cysts are complex fluid-filled or solid masses of cancer cells and are more common after menopause.
What is ovarian cancer?
Ovarian cancer begins when abnormal cells in your ovaries or fallopian tubes grow and multiply out of control. It's the second most common gynecologic cancer in the U.S. but causes more deaths than any other cancer of the female reproductive system. This is because symptoms of ovarian cancer often don't appear until the cancer has spread.
How are ovarian cysts treated?
Treatment for an ovarian cyst will depend on the type and size of the cyst, along with your symptoms. The doctor may recommend:
- Watchful waiting – Functional cysts usually go away on their own, so a wait-and-see approach often is all that's needed. The doctor may perform follow-up ultrasounds to see if the cyst changes in size or appearance.
- Medicine – Hormone-containing medications such as birth control pills can stop ovulation and prevent some future cysts from developing. However, they will not shrink or get rid of an existing cyst.
- Surgery – If your cyst is large, causing pain or doesn't appear to be a functional cyst, it may be removed by surgery. Some cysts may be removed on their own, but in some cases, the ovary also may need to be removed. In the case of ovarian cancer, treatment may include surgery, chemotherapy or both.
There is no data supporting a connection between ovarian cancer and functional cysts, the most common type of ovarian cyst. Because the development of these types of cysts is tied to the menstrual cycle, it's especially rare for women who have not gone through menopause to have a cancerous cyst.
Complex ovarian cysts can raise the risk of developing ovarian cancer but not by much. One study found that 6.5% of women age 50 and older who had a complex ovarian cyst were diagnosed with ovarian cancer within three years.
While the risk of developing ovarian cancer due to an ovarian cyst is small, it's still important to recognize symptoms that may prompt you to talk to your doctor.
Symptoms of ovarian cysts and ovarian cancer
Functional cysts almost never cause symptoms and usually go away on their own within a couple menstrual cycles. In fact, most of these cysts are only noticed during a routine pelvic exam by a gynecologist or primary care physician.
However, if a cyst grows large or presses against something nearby, you may notice mild symptoms. In rare circumstances, an ovarian cyst will rupture or cause the ovary to twist, a condition called ovarian torsion. These situations can cause sudden and intense pain as well as nausea and vomiting. These can be medical emergencies, and you should seek care immediately.
Ovarian cancer can develop and spread throughout your abdomen before it causes any symptoms, making detection difficult. (Related: 5 Warning Signs of Ovarian Cancer to Never Ignore)
However, symptoms of ovarian cysts and ovarian cancer can be similar and may include:
- Heavier or lighter periods than normal
- Irregular periods
- Pelvic pain or a dull ache in your lower back that comes and goes
- Pain during sex
- Trouble moving your bowels or needing to pee more frequently
- Abdominal bloating
- Feeling full after only eating a little food
- Persistent fatigue
If you experience any of these symptoms, see a gynecologist or primary care doctor. They may perform a transvaginal ultrasound to take a closer look at your ovaries. This will let us see the cyst's size, shape and location and whether it appears fluid-filled or solid.
If the cyst looks solid, your doctor may order a blood test for the CA-125 protein, which tends to be elevated when ovarian cancer is present. However, this protein also can be elevated with other conditions, such as endometriosis, uterine fibroids or pelvic inflammatory disease.
Risk factors for ovarian cysts and ovarian cancer
While most ovarian cysts are related to a woman's menstrual cycle, it's not clear what causes ovarian cancer. However, we do know there are a few factors that can increase the likelihood of developing ovarian cysts and ovarian cancer:
- Age – The risk of ovarian cancer increases after menopause.
- Genetics – Some gene mutations, including BRCA1 and BRCA2, can increase the risk of breast cancer and ovarian cancer. Women who have these mutations or have family members with them will want to discuss regular monitoring with their doctor. (Related: What to Do if an Inherited Disease Runs in Your Family)
- Polycystic ovary syndrome (PCOS) – PCOS is a hormonal imbalance that can cause lots of little cysts to develop on the ovaries, along with other symptoms such as irregular periods and infertility. Some studies suggest women with PCOS may have a slightly higher risk of developing ovarian cancer.
Tips to reduce your risk
It's not always possible to entirely prevent getting an ovarian cyst or ovarian cancer. However, there are steps you can take to lower your risk or help find a potential problem before it spreads.
Certain medications that contain hormones, such as birth control pills, may prevent cysts from forming by stopping or regulating ovulation. Birth control pills also can significantly reduce the risk of developing ovarian cancer, especially when taken for longer periods of time.
Dr. Kamat says one of the most important things women can do to determine their risk for ovarian cancer is to get a good family history.
"About 15% of ovarian cancer is linked to genetic alterations that are inherited and run in families," says Dr. Kamat. "Once we identify if a woman is at high risk, we can screen them more often and talk about options to prevent development of the disease, such as risk-reducing surgery to remove organs at high-risk of developing cancer."
If you may be at increased risk for ovarian cancer because of family history, talk with your doctor about screenings, lifestyle changes or tests to help reduce your risk.
Because obesity is associated with an increased risk of ovarian cancer, it's also important to manage your weight through a healthy diet and physical activity.
Regular check-ups with your healthcare provider are key, especially when it comes to ovarian cancer, which rarely causes symptoms until it has spread. During a physical exam of the reproductive organs — the vagina, cervix, uterus, fallopian tubes and ovaries — a doctor can check for signs of illness. (Related: How Often Do You Need a Well-Woman Exam?)
The simple presence of an ovarian cyst is not usually cause for alarm, especially if you are still getting a regular period. But if you have signs of a cyst or concerns about ovarian cancer, talk with your doctor about next steps.
As always, if you feel like your doctor is not listening or taking your concerns seriously, don't hesitate to get a second opinion. You know your body best, and you know when something is not quite right.
