Ovarian cancer and pregnancy
Should a woman worry if she is found to have an ovarian cyst during her pregnancy?
In most cases, no. Ovarian cysts are rather common in pregnancy, especially in the first half. The overwhelming majority of these cysts are innocent, the so-called "functional cysts".
If an ovarian cyst is found while performing an ultrasound scan of the pelvis in pregnancy, the features are analyzed to see if it looks suspicious. It is usually checked with a follow-up ultrasound. If it appears to be increasing in size or changing in character, an operation will be performed to remove the cyst, usually around sixteen to twenty weeks of gestation.
This poses little risk to the pregnancy, is technically not difficult to perform and avoids undue delay in confirming diagnosis. Small cysts of less than 8 cm diameter do not merit any intervention, provided they are not growing.
Surgery to remove cysts could be done by laparoscopy (keyhole) where facilities and expertise is available.
Are there any other potential complications of an ovarian cyst in pregnancy?
Yes. About one in six large ovarian cysts in pregnancy undergo torsion or twisting, which causes quite severe pain. This normally occurs in the first half of pregnancy and is rarer in advanced pregnancy. Torsion can also occur a few days after delivery.
If ovarian cancer is diagnosed during pregnancy, what are the options?
It depends on the type of ovarian cancer, the stage of the disease and the patient's wishes.
Most types of ovarian cancer can be treated adequately with surgery where the ovary and tube are removed and the pregnancy is left to continue. This is provided that the disease is caught at an early stage. If it is more advanced, more extensive surgery may be required while still preserving the pregnancy. The surgery will be followed by chemotherapy which, beyond the first twelve to fifteen weeks of pregnancy, is considered safe for the fetus.
Surgery can, of course, provoke a miscarriage.
Are there forms of ovarian cancer that require treatment with radiotherapy?
Yes. There is a form of ovarian cancer - relatively common in the younger woman - which responds quite well to radiotherapy. It is called a "dysgerminoma".
The best treatment for the disease in the early stages is still surgery but, if it is more advanced, radiotherapy may be necessary for a complete cure.
If the diagnosis is made in early pregnancy, the radiotherapy part of treatment may be deferred until the fetus is viable. This approach requires very careful analysis of all the factors and, of course, the mother's wishes.
How common is ovarian cancer in pregnancy?
Rare. The estimated figure is one in 20,000. An average district hospital with 2,500 deliveries per year will encounter a case of ovarian cancer in pregnancy once every eight to ten years.