Ovarian cysts are a common, but often misunderstood, condition that can cause pain and concern for women. A big part of the confusion around ovarian cysts is that cyst formation is abnormal. In reality, cyst formation is a regular part of the menstrual cycle. An ovulating woman makes a new cyst every month!
What is an Ovarian Cyst?
A cyst is simply a fluid-filled sac with a lining - something like a water balloon placed within the ovary. The vast majority of ovarian cysts are a normal part of the monthly maturation of an egg in preparation for ovulation and possible pregnancy. The technical name for this cyst is a follicle. Follicles always develop around an egg, and, as the cells that surround and support the egg multiply, they begin to secrete fluid. This fluid pushes the cells to the outside thus forming the lining of the cyst. The egg is now enclosed within the follicle wall. By the time the egg is ready to ovulate, it is contained within the wall of a fluid-filled sac that will measure about 2cm in diameter and occupy about one-third to one-half of the ovarian volume.
What Does an Ovarian Cyst Feel Like?
After ovulation occurs and the egg is released into the pelvis, the follicle may once again fill up with fluid or blood and persist. This generally lasts for another week or two, but it can be much longer than that. Sometimes the follicle can fail to rupture and the fluid-filled sac can remain for a few weeks. For some women, the rupture of a cyst can be painful enough to require a visit to the emergency room, and, rarely, even require a surgery to stop bleeding from the cyst.
Types of Ovarian Cysts
While most cysts are part of a normal ovulatory cycle, some cysts form as damage to the surface of the ovary where other cell types get incorporated under the surface of the ovary and accumulate fluid (or sometimes blood) within the cyst.
Risks of Ovarian Cysts
Most ovarian cysts are temporary structures and, if left on their own, will fade away within a week or two. Some cysts, however, can persist for several months. Many of these cysts will have a wall that continues to be active in secreting fluid and may cause the cyst to remain or even grow in size. On rare occasions, a cluster of cyst wall cells will divide more rapidly than normal (a process called neoplasia, or new cell growth) and, over time, can develop pre-cancerous changes or even become an ovarian cancer – although even most neoplastic cyst walls are benign.
The small, but not negligible, risk that a cyst could contain some cancerous cells is what makes them potentially worrisome. For most women of reproductive age, ovarian cysts are more of an inconvenience than something to worry about. However, cysts that become very large, or have been present for several months, are at greater risk to contain neoplastic changes and thus have higher cancer risks.
Ovarian Cyst Treatment
Ultrasound can be very useful and, as resolution improves, continues to get better at detecting neoplasia (which shows up as areas of thickening in the cyst walls). It is not very good, however, at distinguishing between benign neoplasia and malignant neoplasia. The only way to sort that out is through surgery where the cyst wall can be removed and examined under a microscope by a pathologist.
Unfortunately, since most cyst wall thickenings will be benign, studies show that for every ovarian cancer that is detected early, about 8-10 patients will undergo a surgery that they probably didn’t need. However, for those patients where cancer is detected early, it can be life-saving. There are some blood tests like CA-125 that can be of some value in determining the likelihood of a cancer being present, but these are still not nearly as specific as we would like. There is still great debate as to how valuable ultrasound and CA-125 are as cancer screening tools.
For women under the age of 45, when we know that the cyst was not present recently (within 6 months) and there are no areas of thickening in the cyst wall, there is little to worry about. If the cyst is causing pain, it can be drained with an in-office procedure that takes about 5 minutes and can provide significant pain relief. However, since only the fluid and not the cyst wall is removed, the possibility that the fluid may re-collect is about 15-20%. For women over 45, with cysts that are more than 4cm in size and who have not had a prior ultrasound to prove that the cyst has not been present for less than 6 months, or if there is thickening noted in the cyst wall, the cyst is best managed with traditional surgery. Cysts less than 2cm in size rarely cause pain or problems and generally need no treatment, but may need a follow-up ultrasound in a few weeks to make sure they did resolve on their own. Keep in mind, that in reproductive age women, there will always be a few very small cysts that are simply immature follicles waiting to grow towards ovulation. These can generally be ignored.
Q: What are some common causes of ovarian cysts?
A: Risks of developing ovarian cysts can be heightened by the following:
- Pregnancy - The cyst that forms during ovulation can remain on the ovary throughout the pregnancy. In some cases, this cyst may need to be removed.
- Hormonal Problems - These are generally caused by taking various medicines that aid in ovulation.
- Pelvic Infections - Severe infections can spread to and cause cysts to form on the ovaries.
- Endometriosis - For women with Endometriosis, tissues that can grow inside the uterus can develop outside the uterus and cause a cyst to form on the ovaries. These are called endometriomas.
Q: What are the symptoms of having an ovarian cyst?
A: Although most cysts do not cause symptoms, there are a few things to look out for:
- Pelvic pain
- Abdominal pressure
We suggest that you seek immediate medical attention if you experience sudden abdominal or pelvic pain, fever, or vomiting.
Q: What are the different types of ovarian cysts?
A: There are many different types of ovarian cysts (dermoid, hemorrhagic, endometriomas, cystadenomas), but the most common are called functional cysts. The two different types of functional cysts are:
- Follicular Cysts - During the menstrual cycle, the ovary releases an egg. The egg grows inside of the follicle until it eventually breaks out and travels down the fallopian tube. A follicular cyst can form when the follicle doesn't rupture or release its egg, which causes the follicle to grow into a cyst.
- Corpus Luteum Cysts - When a follicle releases its egg, the follicle breaks down into cells called Corpus Luteum which begin producing estrogen and progesterone for conception. If the follicle sac fails to break down, it may reseal and allow fluid to build up inside the follicle, causing a corpus luteum cyst to form.
Q: How are ovarian cysts diagnosed?
A: If your doctor suspects that you may have a cyst, they will begin by completing a pelvic exam to look for swelling. Since cysts do not often require treatment, there are a number of different options the doctor can choose between:
- Imaging Tools (Ultrasound, CT scan, MRI) - Most commonly, ultrasound will be used to create images that allow the doctor to determine the shape, location, and size of the cyst.
- Pregnancy Test - Since ovarian cysts are frequently caused by pregnancy, this is a commonly used preliminary test.
- Hormone Levels Test - This test is used to monitor the individual’s estrogen and progesterone levels and determine the effect the levels may have had on cyst development.
- Blood Test - CA-125 blood tests or commonly issued, especially for post-menopausal women, to screen for signs of ovarian cancer.
Q: What are the options for treating an ovarian cyst?
A: The majority of ovarian cysts will go away on their own and do not require treatment. However, if the ovarian cyst does not go away or continues to grow, there are a few options for treatment.
- Birth Control - This method is usually prescribed to individuals with recurring ovarian cysts. These contraceptives are intended to stop ovulation, which causes the development of new cysts.
- Laparoscopy - If a cyst is deemed to be small and benign, the doctor may opt to make a small incision near the navel and remove the cyst from the abdomen.
- Laparotomy - For larger cysts, especially those at risk of being cancerous, the doctor may choose to perform a Laparotomy. This procedure consists of making a larger incision of the abdomen to remove the cyst, which will then be used to conduct a biopsy.