An ovarian cyst is a fluid filled space in the ovary. They are very common in premenopausal women, especially younger women. Most of them are benign (Nonmalignant - non cancerous).
Broadly speaking, there are 2 types of cysts, physiological or functional cysts, and pathological cysts.
Physiological or Functional Cysts
The physiological cysts arise from the normal functions of the ovary through the menstrual cycle. In the first 2 weeks of the menstrual cycle, an egg develops in a small follicular cyst in the ovaries. By the time of ovulation, the cyst has grown to 2-3cm. Ovulation occurs (egg is released) and the cyst now becomes a corpus luteum. Its function is to make hormones to nurture a pregnancy or prepare the uterus for menstruation. Functional cysts form either in the follicular phase or the luteal phase of the process as outlined above. These cysts are larger, from 5cms, and they continue to make hormones, so menstruation can be delayed.
These cysts are diagnosed by ultrasound scan (USS), showing as perfectly round, fluid filled sacs, and only require removal if they are causing unmanageable pain, or are not resolving. They tend to cause an achy feeling which may last for a few weeks, but usually they will resolve spontaneously. A further USS can be indicated in 2-3 months to see if the cyst has resolved. Women with larger cysts should be aware that increase in pain can indicate torsion (twisting of cyst) or rupture (bursting) so may need further assessment.
Removal of Physiological Cysts
In some cases, the cyst may need to be removed. This would involve a laparoscopy through tiny abdominal incisions to remove the cyst, and you would need to stay in hospital for a night. Women need to be aware that if there was any indication of malignancy (a cancerous cyst) or complications during the procedure that a mini laparotomy may be required (small cut to bikini line area).
Pathological cysts have abnormal features, and are more likely to be solid in appearance. Many of these are benign tumours (non-cancerous), but need to be assessed and removed as they have the possibility of being, or becoming malignant (cancerous). Assessment would involve USS and blood tests for tumour markers, and consultation with a Gynaecologist. Some of the types of cysts would include teratoma (dermoid cysts), which are most common in younger women, serous cystadenoma which has thin, serous fluid, mucinous cystadenoma, which are large cysts with thick fluid. These types of cysts will keep growing until they are removed.
Removal of Pathological Cysts
The surgery for these cysts would be laparotomy (incision in abdomen) which would mean a hospital stay of 1-2 nights depending on the size of incision, and the type of surgery. For postmenopausal women a more extensive operation is likely to be recommended as the risk of malignancy is increased in this age group.
Other pathological cysts are endometriomas (chocolate cysts), which are lumps of endometriosis that grow in the ovaries, and have dark brown fluid inside them. They would be removed as part of laparoscopy for endometriosis.