OVARIAN CYST (Written by Christian Nordqvist )

What Is An Ovarian Cyst? What Causes Ovarian Cysts?


An ovarian cyst is an accumulation of fluid within an ovary that is surrounded by a very thin wall. Any ovarian follicle that is larger than approximately two centimeters is an ovarian cyst. 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.

The majority of ovarian cysts are benign (harmless). According to the Centers for Disease Control and Prevention (CDC), USA, most premenopausal women and up to 14.8% of postmenopausal women are found to have ovarian cysts.

Ovarian cysts typically 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 5 centimeters 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).
What is a cyst?
A cyst is a closed sac-like structure - an abnormal pocket of fluid, similar to a blister - that contains either liquid, gaseous, or semi-solid material. A cyst is located within a tissue, and can develop anywhere in the body and may vary in size - some are so tiny they can only be observed through a microscope, while others may become so large that they displace normal organs.

In anatomy, a cyst can also refer to any normal bag or sac in the body, such as the bladder. In this text, cyst refers to an abnormal sac or pocket in the body that contains either liquid, gaseous or semi-solid substances.

A cyst is not a normal part of the tissue where it is located. 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 an abscess. Some cysts are solid and may be called tumors (pathological cysts). The word tumor does not necessarily mean it is cancerous - a tumor is a medical term for a swelling.

According to Medilexicon's medical dictionary:


An ovarian cyst is "a cystic tumor of the ovary, either nonneoplastic (follicle, lutein, germinal inclusion, or endometrial) or neoplastic; usually restricted to benign cysts, mucinous serous cystadenoma, or dermoid cysts."
What are the signs and symptoms of an ovarian cyst?
A symptom is something the patient feels and reports, while a sign is something other people, such as the doctor detect. For example, pain may be a symptom while a rash may be a sign.

In the vast majority of cases, ovarian cysts are small and benign (harmless); there will be no signs or symptoms.

Even if there are symptoms, they alone cannot determine whether a patient has an ovarian cyst. There are several other conditions with similar signs and symptoms, including endometriosis, pelvic inflammatory disease, ectopic pregnancy or ovarian cancer. A ruptured ovarian cyst may present similar signs and symptoms to those of appendicitis or diverticulitis.

The 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.
Pelvic pain may appear just before menstruation begins
Pelvic pain may occur just before menstruation ends
Dyspareunia - pelvic pain during sexual intercourse. Some women may experience pain and discomfort in the abdomen after sex.
Pain when passing a stool (doing a poo)
Pressure on the bowels
Some pregnancy symptoms, including breast tenderness and/or nausea
Bloating, swelling, or heaviness in the abdomen
Problems fully emptying the bladder
Pressure on the rectum or bladder - the patient may have to go to the toilet more often, either to urinate or pass a stool.
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.
Complicated cyst signs and symptoms

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.

Bursting - if the ovarian cyst 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 rarer cases an ovarian cyst may be an early form of ovarian cancer.
What are the causes of ovarian cysts?
Functional ovarian cysts - there are two types:
Follicular cysts - the most common type of ovarian cyst. A female human has two ovaries, small round organs which release an egg every month. The egg moves into the uterus (womb), where it can be fertilized by a male sperm. The egg is formed in a follicle which contains fluid to protect the growing egg. When the egg is released the follicle bursts.

In some cases, the follicle either does not shed its fluid and shrink after releasing the egg, or does not release the egg. The follicle swells with fluid, becoming a follicular ovarian cyst. Typically, one cyst appears at any one time and normally goes away within a few weeks (without treatment).


Luteal ovarian cysts - these are much less common. After an egg has been released it leaves tissue behind (corpus luteum). Luteal cysts can develop when the corpus luteum fills with blood. In most cases, this type of cyst goes away within a few months. However, it may sometimes split (rupture), causing sudden pain and internal bleeding.
Pathological cysts - 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) - this is a bizarre tumor, usually benign. This type of cyst develops from a totipotential germ cell (a primary oocyte) - in other words, the cell can give rise to all orders of cells necessary to form mature tissues. Dermoid cysts contain hair, skin, bone and other tissues (sometimes even teeth). A totipotential germ cell has the ability to develop in any direction. They are formed from cells that make eggs. These type of cysts need to be removed surgically.

Cystadenomas - these ovarian cysts 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. Rather than growing inside the ovary itself, cystadenomas are usually attached to an ovary by a stalk. By existing outside the ovary they have the potential to grow considerably. Although they are rarely cancerous, they need to be removed surgically.

The following conditions may increase the risk of developing ovarian cysts:

Endometriosis - a condition in which cells that are normally found inside the uterus (endometrial cells) are found growing outside of the uterus. That is, the lining of the inside of the uterus is found outside of it. Endometrial cells are the cells that shed every month during menstruation, and so endometriosis is most likely to affect women during their childbearing years. Women with this condition have a higher risk of developing ovarian cysts.

Polycystic ovarian syndrome (PCOS) - in this condition many small and harmless cysts develop on the ovaries, caused by a problem with hormone balance produced by the ovaries. People with PCOS have a higher risk of developing ovarian cysts.
Diagnosing ovarian cysts
As most ovarian cysts present no signs or symptoms, they frequently go undiagnosed. This also makes it difficult to accurately estimate incidence and prevalence of the condition. Sometimes, even without symptoms, a cyst may be diagnosed during an unrelated pelvic examination or ultrasound scan.

Patients with ovarian cyst symptoms will probably be referred by their GP (general practitioner, primary care physician) to a doctor who specializes in women's reproductive health - a gynecologist.

The specialist will carry out a physical examination, focusing on possible signs and symptoms.

In determining a diagnosis, doctors need to know:
The shape of the cyst.
The size of the cyst.
The composition of the cyst - is it filled with solid, fluid or both? In most cases fluid-filled cysts are not cancerous. Some may require further tests to find out.
The following diagnostic tests may also be ordered:
Ultrasound scan - this will be carried out to help the doctor make a diagnosis. A wand-like scanner probe (transducer) is placed on the abdomen, over where the ovaries are. Sometimes the probe may be placed inside the vagina. In both cases, the doctor is observing the ovaries on a video screen. This test can help the doctor determine whether there is a cyst, and whether it is solid, filled with fluid (or both).


Blood test - if there is a tumor present blood levels of CA125 (a protein) 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.


Pregnancy test - a positive result may suggest the patient has a corpus luteum cyst.


Laparoscopy - a thin, lighted instrument (laparoscope) is inserted into the patient's abdomen through a small incision (skin cut). If the doctor spots an ovarian cyst he/she may also remove it there and then.
What are the treatment options for ovarian cysts?
Several factors are taken into account when deciding on the type of treatment for ovarian cysts; and whether to treat 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, the doctor may recommend birth control pills. Oral contraceptives also reduce the risk of developing ovarian cancer.

Surgery - 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, the doctor 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.
Laparoscopy (key hole 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 is able to 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 - this 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.
Cancer treatment - if the cyst is cancerous the patient may need to have more organs and tissue removed, including the ovaries, uterus, the omentum and some lymph nodes.
Prevention
There is no definite way of preventing ovarian cyst growth. However, regular pelvic examinations, which allow for early treatment if needed, usually protect the woman from complications.