The treatment of an ovarian cyst depends on what type of cyst is present. Unfortunately, even with the very best imaging and assessment it is not possible to be certain about the nature of an ovarian cyst. The treatment has to be decided on the basis of probability of various cyst types rather than certainty. One of the key issues is the possibility that the cyst is cancerous. With most simple cysts this is very unlikely, but often this possibility cannot be completely excluded.
A simple “Risk of Malignancy Index” has been developed which takes into account the CA125 level, menopausal status and ultrasound findings. This is a guide that can be useful in raising suspicion of malignancy in some cases, although it is not very helpful with endometriosis as the ultrasound appearances are often complex and CA125 may be raised significantly. Other risk scores have been developed which perform better than the RMI.
With most ovarian cysts diagnosed, the suspicion of malignancy is very low and the women can be reassured.
When is surgery necessary?
Functional cysts usually resolve spontaneously over several weeks or months. If a cyst is thought to be functional a repeat scan in 4 to 6 weeks is usually arranged. It is only necessary to remove a simple cyst if it persists over several months or causes symptoms.
The factors that determine whether a cyst should be removed are
- Complexity. If an ovarian cyst has septae, solid areas, an irregular wall or increased blood flow.
- Size. Over 5 cm is considered more significant.
- Symptoms attributable to the cyst
- The nature of the cyst suggesting whether it will resolve spontaneously or not.
- Risk that the cyst is cancerous
Types of Surgery for Ovarian Cysts
Laparoscopic (Keyhole) surgery
Many cysts can be removed using keyhole surgery. This allows dissection and removal of the cyst without an abdominal incision with a quicker return to normal activities. The operation is performed using a telescope in an incision in the umbilicus and usually two other ports lower down on the abdomen. The cyst is placed in a bag and the fluid removed before the cyst wall is removed through one of the ports.
Recently robotic surgery has been used to improve keyhole surgery. This approach allows very much more precise surgery with even quicker recovery. Robotic surgery can be performed through a single port in the umbilicus making it virtually “scarless”.
If the cyst is possibly a cancer, even if that risk is low, an open operation is usually better, as laparoscopic surgery is more likely to spread the tumour than an open operation. Often this can be performed through a small incision and return to normal activities is almost as quick as with keyhole surgery.
Will I need any follow-up?
Most women are seen for one or two visits after surgery to make sure that they have healed well. The risk of a further ovarian cyst depends on the nature of the cyst. Most ovarian cysts have no tendency to recur and so further follow-up is not necessary.
Does removal of an ovarian cyst affect fertility?
Removing a cyst from one or both ovaries should not affect the function of the ovary and so fertility and periods should not be affected. Sometimes surgery can cause adhesions where organs within the abdomen stick together. If adhesions occur around the ovaries or fallopian tubes, they can affect the transfer of eggs released from the ovaries to the fallopian tubes. During surgery it is important to handle the tissues within the pelvis gently to avoid damage to the surface and to reduce the risk of adhesion formation. With careful surgery, adhesions that affect fertility are very uncommon unless another abnormality is present such as endometriosis or pelvic infection.
When is an ovarian cyst not an ovarian cyst?
Occasionally cysts in other structures will ‘mimic’ ovarian cysts. Common examples of this are fimbrial cysts on the end of the fallopian tube, and a hydrosalpinx which is a fluid collection within the fallopian tube. Fibroids sometimes occur in the tissue next to the ovary called the broad ligament and so appear to be attached to the ovary.