A benign tumour of the ovary, of which there are many varieties. The most common is a follicular cyst, resulting from growth of a Graafian follicle that fails to ovulate or from involution of a mature follicle. It may rupture, causing pain. A luteal cyst occurs after an egg has been released from a follicle, which then becomes a corpus luteum; instead of breaking down if a pregnancy does not occur, it fills with blood or fluid. It is usually found on only one side of the ovary and produces no symptoms. Although most ovarian cysts are not malignant, they may reach a very large size, causing gross swelling of the abdomen and pressure on surrounding organs. The cyst may rotate on its stalk, thus cutting off its blood supply and causing severe abdominal pain and vomiting. In this case the cyst requires urgent surgical removal. Ovarian cysts that do become malignant may not be recognized until the tumour has advanced to a stage where treatment may be unsuccessful in eradicating the cancer. Screening programmes, based on ultrasound techniques, and CA125 estimation, have been introduced in some areas to assist with the early detection of ovarian cysts and tumours.
Subjects: Medicine and Health.