An ovarian cyst is accumulation of fluid lined by a thin wall within ovary. These cysts may contain clear fluid, blood, mucinous material (sticky thin jelly like fluid) or chocolate material etc. A cyst is not a normal part of the ovaries. It has a distinct membrane and division on nearby tissue - the outer or capsular portion of a cyst is called the cyst wall. If the sac is filled with pus it is not a cyst, it is called as an abscess.
Ovarian cysts can range widely in size; from being as small as a pea to larger than an orange - in rare cases ovarian cysts can become so large that the woman looks pregnant.
We have seen ovarian cysts occupying whole abdomen looking like nine months pregnant lady.
The majority of ovarian cysts are benign (harmless, noncncerous).
Ovarian cysts occur most frequently during a female's reproductive years (childbearing years). However, ovarian cysts may affect a woman of any age. In some cases, ovarian cysts cause pain and bleeding. If the cyst is over 5cm in diameter, it may need to be surgically removed.
There are two main types of ovarian cysts:
. Functional ovarian cysts - the most common type. These harmless cysts form part of the female's normal menstrual cycle and are short-lived.
. Pathological cysts - these are cysts than grow in the ovaries; they may be harmless (benign) or cancerous (malignant).
Causes of ovarian cysts
Functional ovarian cysts
There are two types of functional ovarian cysts:
1) Follicular cysts
Follicular cysts are the most common type of ovarian cyst.
Ovaries generate one egg in each menstrual cycle and this egg is generated in side the follicle. Follicle is a fluid containing bag which grows up to 18-24 mm in size and ruptures when the contended egg is mature.
In some cases, the follicle either does not get ruptured and egg is not released. The follicle enlarges swells with fluid, becoming a follicular ovarian cyst. Typically, one cyst appears at any one time and normally goes away within a few weeks (with or without treatment).
2) Luteal ovarian cysts
These are much less common. After the egg has been released follicle becomes corpus luteum. Sometimes corpus luteum enlarges due to bleeding from inside. It may mimic acute emergency. Usually patient presents with severe lower abdominal pain and associated symptoms like nausea vomiting and giddiness. Usually cyst resolves on its own but rarely may require surgery.
Dermoid cysts are the most common type of pathological cyst for women under 30 years of age. Cystadenomas are more common among women aged over 40 years.
Dermoid cysts (cystic teratomas)
A dermoid cyst is a bizarre tumor, usually benign(non cancerous). The ovary contains totipotent cells (cells capable of forming any organ).Normally these totipotent cells form eggs but in some cases they can give rise to cyst called as dermoid cyst. Dermoid cysts contain hair, skin, bone and other tissues (sometimes even teeth). These cysts will not respond to medicines and will need to be removed surgically.
Cystadenomas are ovarian cysts that develop from cells that cover the outer part of the ovary. Some are filled with a thick, mucous substance, while others contain a watery liquid. As they develop from the surface of the ovary they grow outside the ovary and may attend huge size. Cystadenoma containing clear fluid are called as serous Cystadenomas and the other which contain thick mucinous sticky fluid are called as mucinous cyscadenomas. These are non cancerous tumours and very rarely turn cancerous. No medicine will dissolve these cysts and these also require surgery to remove them.
Symptoms of ovarian cysts
In the vast majority of cases, ovarian cysts are small and benign (harmless); there will be no signs or symptoms.
Signs and symptoms of an ovarian cyst may include:
. Irregular menstruation - periods may also become painful, heavier or lighter than normal.
. A pain in the pelvis. This may be persistent pain or an intermittent dull ache that may spread to the lower back and thighs.
. Dyspareunia - pelvic pain during sexual intercourse. Some women may experience pain and discomfort in the abdomen after sex.
. Pain when passing a stool.
. Symptoms due to pressure like frequency of urination or motions.
. Some pregnancy symptoms, like distension of abdomen, including breast tenderness and nausea.
. Bloating, heaviness in the abdomen
. Hormonal abnormalities - in some rare cases the body produces abnormal amounts of hormones, resulting in changes in the way the breasts and body hair grow.
. Torsion - the stem of an ovary can become twisted if the cyst is growing on the stem, blocking the blood supply to the cyst and causing severe pain in the lower abdomen
. Rupture - if the ovarian cyst ruptures/bursts, the patient will experience severe pain in the lower abdomen. If the cyst is infected pain will be worse. There may also be bleeding
. Cancer - in rare cases an ovarian cyst may be an early form of ovarian cancer.
Diagnosing ovarian cysts
Ovarian cysts may be diagnosed by simple internal examination but following tests are usually carried out to confirm diagnosis:
Ultrasound scan:Ultrasound scan or sonography is the basic diagnostic test which can detect practically all ovarian cysts. It can be done Trans abdominally or Trans vaginally. For unmarried ladies only transabdominal scan is done while transvaginal scan can be done for married or sexually active lady. Ultrasound can tell us about size, site, and type of the cyst. In most of the cases sonography is enough to diagnose the cysts but in some cases diagnosis is confirmed by doing other tests.
If we suspect some malignancy/ cancer we do some specific blood tests. Most common blood test done when an ovarian cyst id diagnosed is CA 125. If there is a tumor present blood levels of CA125 will be elevated. High CA125 levels could also mean the patient has ovarian cancer. If a woman develops an ovarian cyst that is partially solid, she may have ovarian cancer. High CA125 levels may also be present in other conditions, including endometriosis, uterine fibroids or pelvic inflammatory disease.
A positive pregnancy test result may suggest the patient has a corpus luteum cyst.
A thin, lighted instrument called a laparoscope is inserted into the patient's abdomen through a small incision (skin cut).
Treatments for ovarian cysts
Several factors are taken into account when deciding on the type of treatment for ovarian cysts and whether to treat it at all.
The main factors are:
. The patient's age
. Whether the patient is pre- or postmenopausal
. The appearance of the cyst
. The size of the cyst
. Whether or not there are any symptoms.
Watchful waiting (observation)
Sometimes watchful waiting, also known as observation is recommended, especially if the woman is pre-menopausal, and she has a small functional cyst (2cm to 5cm).
An ultrasound scan will be carried out about a month or so later to check it, and to see whether it has gone.
Post-menopausal women are monitored with ultrasound scans, as well as blood tests to check their CA125 levels. The approach depends very much on the size of the cyst and whether it has changed over time.
If a woman has small cysts in just one ovary her risk of developing cancer is very small. In most cases, such cysts go away within three months. Post-menopausal women should undergo a follow-up ultrasound scan four months after the cyst has gone away.
Birth control pills
To reduce the risk of new cysts developing in future menstrual cycles, we may recommend birth control pills. Oral contraceptives also reduce the risk of developing ovarian cancer.
If there are symptoms, the cyst is large, does not look like a functional cyst, is growing, or persists through two or three menstrual cycles; we may recommend that the patient have it surgically removed. In some cases if a cyst is found and no symptoms are present, surgical removal is still recommended - this is because it is not possible to know what type of cyst it is without examining it under a microscope. Removing it addresses the risk of the cyst eventually becoming cancerous.
Two types of surgery that may take place are:
Laparoscopy (keyhole surgery)
Two small cuts are made in the lower abdomen and one in the belly button. Gas is blown into the pelvis to raise the wall of the abdomen, away from the internal organs. A small tube with a light on the end (a laparoscope) is inserted into the abdomen. The surgeon can see the internal organs. With very small tools the surgeon can remove the cyst through the small incisions. In some cases a sample (biopsy) of the cyst is taken to determine what type it is.
In most cases, the patient can go home the same day. This type of surgery does not usually affect a woman's fertility, and recovery times are much faster.
Laparotomy is a more serious operation and may be recommended if the cyst is cancerous. A longer cut is made across the top of the pubic hairline, giving the surgeon better access to the cyst. The cyst is removed and sent to the lab. The patient usually has to remain in hospital for at least a couple of days.
If the cyst is cancerous, the patient may need to undergo a major surgery in which we remove both the ovaries, uterus, both the fallopian tubes and the omentum and some lymph nodes. There this cancer surgery, the tissue removed is sent for microscopic examination to see for the spread of the cancer and accordingly further treatment is advised.