Ovarian cancer is a disease where some of the cells in one or both ovaries start to grown abnormally and develop into cancer.
The ovaries are two small almond shaped organs that are part of the female reproductive system. Each ovary measures about 2-4cm across and they sit on either side of the uterus.
Each ovary contains germ cells that eventually develop into eggs (ova). The ovaries also produce the hormones oestrogen and progesterone, which regulate your menstrual cycle and affect the development of female body characteristics.
There are four main types of ovarian cancer, and these are named after the type of cells in the ovary where the cancer begins growing:
- Epithelial ovarian cancer begins in the epithelium, the outer cells that cover the ovary. This is the most common type of ovarian cancer, accounting for about 90% of cases.
- Borderline tumours are a group of epithelial tumours which are not as aggressive as other epithelial tumours. Borderline tumours may also be called ‘low malignant potential’ or LMPO tumours. The outlook for women with borderline tumours is generally good regardless of whether the disease is diagnosed early or late.
- Germ cell ovarian cancer begins in the cells that mature into eggs. These tumours account for about 5% of ovarian cancers and usually affect women under 30 years.
- Sex-cord stromal cell cancer begins in the ovary cells that release female hormones. These tumours account for about 5% of ovarian cancers and can affect women of any age. Both germ cell and sex-cord stromal cell ovarian cancers respond well to treatment and are often curable. If either of these cancers affect only one ovary, it may be possible for younger women to have children after treatment.
If your doctor suspects ovarian cancer, there are a number of tests they can perform to help decide whether your symptoms are due to ovarian cancer or other causes. Of these tests, it is strongly recommended that both the CA125 blood test and the transvaginal ultrasound are performed.
There isn’t any one test that can be used to diagnose ovarian cancer. Doctors use both a blood test and a transvaginal ultrasound (and possibly other tests) to help make a diagnosis. If these tests strongly suggest ovarian cancer, then your doctor will recommend an operation, which is the only definite way to diagnose ovarian cancer.
Initial examinations and tests will usually include:
- Physical examination. Your doctor will examine you physically and this will include an internal pelvic examination where they check for a mass or a lump in the lower abdomen or pelvis.
- Blood tests. Your blood will be tested for a particular protein or a tumour marker called CA125. This protein is often higher than normal in women with ovarian cancer. Some women may have other tumour markers called inhibin or CEA. The type of marker depends on the type of tumour. However, some tumours will not have any of these tumour markers. Testing your blood for these tumour markers is one way to help diagnose cancer. In women who are diagnosed with ovarian cancer, these tests are also used later on to check the progress of the illness.
- Ultrasound. A transvaginal ultrasound (TVU) involves an ultrasound probe being inserted into your vagina to relay image of the ovaries to a radiologist. It is important that this type of ultrasound is used as it gives a much clearer picture of the ovaries than an abdominal or external ultrasound.
- Other imagine tests. Sometimes your doctor may organise other imaging tests. These may include chest or abdominal x-rays, an ultrasound or your lower abdomen, a CT scan, or possibly an MRI.
Your doctor may order an x-ray of your bowel called a barium enema to see if a bowel problem is causing your symptoms.