A fluid filled area of the ovary is called an ovarian cyst. These can be large or small, benign or cancerous, worrisome or part of the normal function of the ovary. So how do we tell the difference? If an ovarian cyst is felt on pelvic exam, and confirmed by ultrasound we can tell a lot. If the cyst is smooth and completely filled with clear fluid, chances are it is not too dangerous. If it is smaller than 2 inches (5 cm) in diameter it may very well go away on its own. This scenario accounts for the vast majority of ovarian cysts. Most women will have some sort of functional ovarian cyst at one time or another in her lifetime. Personally, this has happened to me on two occasions. Each time the cyst healed on its own in 4 – 6 weeks. If it is closer to 10 cm or 4 inches it is less likely to go away on its own. And if the cyst is not completely clear, but has a more “complex” appearance it may either be a hemorrhagic cyst, a cyst caused by bleeding into the ovary with ovulation, or an endometrioma, a cyst from endometriosis of the ovary. Both of these conditions are benign. A hemorrhagic or ovulatory cyst will heal on its own, an endometrioma will not. This information applies to women before menopause, the group most likely to develop ovarian cysts.
After menopause it is less likely to have ovulation related cysts. Still, benign cysts are more common than cancer of the ovary even in older patients. The likelihood of getting ovarian cancer in our lifetime is 1.7%. At age 60 this is only 1 of every 1500 women.
There are other cysts that may form in the ovary. Among the most confusing and interesting is the Dermoid Cyst. This is where an ovarian “egg” cell forms a cyst containing hair and possibly a tooth or other bodily tissues. These are almost always benign with a cancer rate of 1/1000. Dermoid cysts are fairly typical in appearance on ultrasound or X-Ray and easily removed by minimally invasive means with a laparoscope.
A cyst is often diagnosed after a woman complains of lower pelvic pain because the covering of the ovary is sensitive. It is called peritoneum, and when this covering is stretched and inflamed it can cause peritonitis. When I had a cyst on the right, I was actually concerned that it could be appendicitis. This is not uncommon. Examination and ultrasound help differentiate the causes of pain. A cyst might be diagnosed on an exam without any symptoms at all.
Should a CA 125 blood test be done? This is question I am asked daily. Only under very few circumstances is this test helpful. If a woman is pre-menopausal, there are many causes of an elevated test result that are unrelated to ovarian cancer. BUT, if the patient is past menopause, and there is an ovarian cyst present, it might shed some light on the situation. Many women ask me for this test with the attitude “well, how could it hurt to get more information?” Let me explain. In two national studies looking at screening healthy woman for ovarian cancer with ultrasound and CA 125 at Yale University and Cedars Sinai Medical Center in Los Angeles for 10 years, it was discovered that for every cancer found, there were 70 women with elevated CA 125 tests. These women were worried, had X-Rays and tests, some had their normal ovaries removed with all the risk of surgery that that entails. Only 6 cancers were found from several thousand patients and only 1 of these was early. So it is concluded that the CA 125 test is not effective in finding early cancer, that it is not specific enough and finds more non-cancer than actual cancer, and that the risks of the test are greater than the benefits in an otherwise healthy woman. That said, the test is helpful in the presence of an ovarian mass or cyst in a woman after menopause.
Most ovarian cysts are treated laparoscopically. This allows the doctor to be very conservative, leaving all normal tissue and removing only the cyst tissue. Since these are usually benign, they can be drained inside and removed through a half-inch opening. This is out patient surgery and most patients are back to work in 1 – 2 weeks. Only on rare occasion is it necessary to remove the entire ovary, even when the cyst occupies most of the ovary, the tissue left behind can reconstitute itself back into an ovary and ovulate. Conserving ovarian tissue is imperative for future fertility as well as for the manufacture of estrogen, progesterone, and testosterone, which have been shown to have health benefits throughout life. The complete ovary might need to be removed if it is twisted around itself, a torsion, which can block off the blood supply (although the ovary may be saved if this is diagnosed early enough in the process). Or the ovary may be completely destroyed by the disease process undergoing treatment.
Some cysts are bilateral, present on both sides, so both ovaries need to be carefully examined.
Some cysts may be suspicious for cancer. If they are small enough to be sequestered in a surgical bag, they can be removed laparoscopically, placed in the bag, drained in the bag and removed piecemeal from within this bag. If cancer is found, the remainder of the surgery, a staging surgery to evaluate the extent of the disease may be done either laparoscopically or through an incision, depending on the circumstances.
Again, the good news is that most ovarian cysts will heal on their own, most are benign, and most that require removal can be removed in a minimally invasive, outpatient surgery.