Ovarian cysts are fluid-filled sacs that form within the ovary. They vary in size and content, and may be benign or malignant. Most cysts are asymptomatic and non-cancerous, and resolve spontaneously without any treatment.
Functional cysts develop as part of a normal menstrual cycle. These include:
Polycystic ovaries are ovaries containing multiple small follicles. This may be seen in conjunction with irregular menses, subfertility and symptoms of hormonal imbalance like oily skin, acne and increased hair growth.
Benign ovarian cysts include:
The majority of ovarian cysts are asymptomatic. Larger ovarian cysts may twist or rupture, resulting in acute abdominal pain, nausea and vomiting. Patients with endometriotic cysts may present with painful menses (dysmenorrhoea) and intercourse (dyspareunia).
Other symptoms include:
As ovarian cancer tends to develop insidiously with vague symptoms, the above symptoms should not be ignored, especially if they are new or experienced on a frequent basis.
Risk factors include:
However, as many people who develop cancer have no risk factors, it is imperative that all women with ovarian cysts are properly evaluated for this possibility.
Ultrasound is the preferred method for characterising ovarian cysts. Features such as solid areas, multiple internal compartments, irregular margins and high velocity blood flow increase the index of suspicion for ovarian cancer.
A blood test for CA125 may be taken if
there is concern about malignancy. This
blood protein is frequently raised in
ovarian cancer, but must be interpreted
in conjunction with symptoms and
ultrasound findings as it can also be
raised in non-cancerous conditions
such as endometriosis and fibroids.
Management depends on your symptoms, characteristics of the cyst and results of blood tests.
Small asymptomatic ovarian cysts that have no suspicious features on ultrasound may be managed expectantly. This usually involves a follow-up ultrasound scan in about three to four months to monitor for any change in size or appearance of the cyst.
Surgery will be recommended if the ovarian cyst is symptomatic or has abnormal features.
Laparoscopy (keyhole surgery) is the approach of choice if the risk of malignancy is low, as it is associated with less post-operative pain and a faster recovery.
Laparotomy (open surgery) may be recommended if you have had previous surgery, if the ovarian cyst is large or if it has suspicious features.
Cystectomy involves removal of the cyst with preservation of normal ovarian tissue. This is usually done for pre-menopausal women in order to conserve ovarian tissue for reproductive and hormonal function.
Oophorectomy is the surgical procedure to remove the entire ovary. Post-menopausal women will usually be offered removal of both ovaries as this has the advantage of reducing the risk of developing ovarian cancer or cysts in the future.
If the risk of ovarian cancer is high, your doctor will discuss frozen section and surgical staging.
Frozen section involves sending the excised ovarian tissue for microscopic examination while you are still under general anaesthesia. If this test reveals malignant cells and you have given prior consent, your surgeon may then proceed to perform a full staging surgery as part of the treatment for ovarian cancer. This involves removing the uterus, both fallopian tubes and ovaries, the omentum (a layer of fatty tissue that covers the abdominal contents like an apron) as well as lymph nodes.