An ovarian cyst is a sac or pouch filled with fluid or other tissue that forms on the ovary. Ovarian cysts may occur at any age, individually or in numbers, on one or both ovaries. More than half of all ovarian cysts are functional, meaning that they arise out of the normal functions of the ovary during the menstrual cycle.
Although majority of ovarian cysts in post-menopausal women are benign, some may have cancerous changes.
There are a few complications that can happen to ovarian cyst, so called ovarian cyst “accident”. They are cyst rupture, haemorrhage and torsion (twisting).
A cyst can form when a follicle has grown in preparation for ovulation but fails to rupture and release an egg; this type is called a follicular cyst. Sometimes the structure formed from the follicle after ovulation, the corpus luteum, fails to shrink and forms a cyst; this is called a corpus luteum cyst.
Another type of ovarian cyst, most often found in younger women, is the dermoid cyst, which contains particles of teeth, hair, or calcium-containing tissue that are thought to be an embryologic (developmental) remnant; such cysts usually do not cause menstrual irregularity and are very common. Dermoid cysts are often (up to 25 percent of cases) occur on both sides, making careful examination of both ovaries mandatory.
Endometrial (lining of the womb) cells can sometimes have implants on the ovary, and over time develop endometriomas. These cysts are filled with old blood, giving a classical “ground glass” appearance on ultrasound. When ruptured, chocolate like material drains, so they are often called also as chocolate cysts.
These cysts are generally not cancerous. However endometriosis/ endometrioma is a known risk factor for ovarian cancer.
Smaller cysts often do not cause any symptoms, however with large cysts, symptoms may include:
An ovarian cyst may be found during a routine pelvic examination. Not infrequently it is found incidentally whilst investigating other conditions.
The first line of investigation for ovarian cyst is pelvic ultrasound, preferably vaginal ultrasound.
In post-menopausal women, in addition to an ultrasound examination, a blood test for CA 125 is requested. An increased CA 125 level may be a sign of ovarian cancer in women past menopause. In pre-menopausal women, an increased CA 125 level can be caused by many other conditions besides cancer. Therefore, this test is not a good indicator of ovarian cancer in pre-menopausal women.
In the case of the functional ovarian cyst, if no severe pain or swelling is present, “watchful waiting” approach for one or two more menstrual cycles is acceptable. This type of cyst frequently disappears spontaneously. Sometimes this process is hastened by administering oral contraceptives for several months, which establishes a regular menstrual cycle. Women already taking oral contraceptives rarely develop ovarian cysts.
In the case of symptomatic, persistent cysts or “complex” appearing cysts, a planned surgical removal is recommended. In most cases, healthy ovarian tissue can be conserved and only cystectomy (removal of the cyst) is necessary.
When a cyst is twisted or ruptured, emergency surgical treatment is indicated, preferably the removal of the cyst only and preservation of as much of the normal ovarian tissue as possible. Sometimes, with a very large cyst, the ovary cannot be saved and must be removed, requiring a procedure called oophorectomy.
Dr Sem is an expert laparoscopic surgeon, and in majority of cases will be able to complete the procedures laparoscopically.