Ovarian cancer

Contents:

• General
• Risk Factors
• Prevention
• Screening
• Symptoms
• Diagnosis
• Treatment
• Statistics

General

Ovarian cancer develops in the cells of the ovary. Women have two ovaries, one on each side of the uterus. The ovaries produce eggs and are the main source of the female hormones estrogen and progesterone that both regulate the menstrual cycle and are responsible for female body characteristics. About 9 in 10 ovarian cancers start in the cells that cover the outer surface of the ovary and are known as epithelial ovarian cancers.

Risk factors

Age

Most ovarian cancers happen after the menopause. Half of all these cancers are found in women over the age of 65.

Children

Women who have not had children, or who had their first child after they were 30 years old have a small increased risk.

Diet

Some studies suggest that a high fat diet may increase ovarian cancer risk, other studies do not show a link.

Menstrual periods

There seems to be a link between the number of periods (menstrual cycles) a woman has in her lifetime and her risk of getting ovarian cancer. Women who start having periods early (before 12 years of age) or who go through the menopause after the age of 50 have a small increased risk of ovarian cancer.

Fertility drugs

Prolonged use of fertility drugs, especially if a woman does not get pregnant, might increase the risk of ovarian cancer. However infertility also increases the risk, even without the use of fertility drugs. Research in this area is now going on.

Family history of ovarian, breast, or bowel cancer

Inherited ovarian cancer is rare and accounts for only around 1 in 20 cases. The risk of getting ovarian cancer is increased if there is a first-degree relative (mother, sister, daughter) with the disease, especially if they developed it at a young age.

Genetics

There are several genetic factors that increase the risk of ovarian cancer, such as inherited gene mutations of the BRCA1 and BRCA2 genes, and an inherited disease known as Hereditary Nonpolyposis Colon Cancer (HNPCC).

Breast cancer

Women who have had breast cancer have a higher risk of ovarian cancer.

Talcum powder

Some studies have shown a slight increase in risk of ovarian cancer among women who used talc on the genital area. Asbestos used to be used in the powder which may explain the link. For more than 20 years these products have been free of asbestos. Proving the safety of newer products will require further follow-up studies.

Estrogen replacement therapy (ERT)

Most studies suggest that long-term use (10 years or more) of ERT after menopause may slightly increase the risk of ovarian cancer. ERT is rarely used any more except in women who have had a hysterectomy (removal of the uterus).

Hormone replacement therapy (HRT)

Combined HRT, where progesterone is given with the estrogen, seems to have little if any impact on ovarian cancer risk.

Prevention

Birth control pills

Birth control pills reduce the risk of ovarian cancer, especially among women who use them for several years. However more research is needed to make clear the advantages of the pill for woman at high risk of ovarian and breast cancer.

Diet

A low fat diet may help to prevent ovarian cancer.

Tubal ligation or hysterectomy

"Tying" the tubes as a method of birth control after childbearing may reduce the risk of ovarian cancer. Removing the uterus may also reduce the risk.

Pregnancy and breast-feeding

Having children before the age of thirty, and/or breast-feeding for over one year may decrease the risk of ovarian cancer.

Aspirin

Some studies have shown that both aspirin and paracetamol reduce the risk of ovarian cancer. But there is some doubt about this. These drugs should not take be taken simply to prevent cancer.

Preventative ovary removal (oophorectomy)

Surgery to remove one or both ovaries is called oophorectomy. It can be done before cancer develops in order to lower the risk. The surgery causes an early menopause. It is often suggested only for certain women over the age of 40 who are at very high risk.

Recent research shows that women who have certain gene changes (mutations) and who have their ovaries removed have a reduced risk of ovarian and breast cancer. While this operation significantly lowers ovarian cancer risk, cancer can still form in the cells lining the pelvic cavity where the ovaries were located.

Screening

There are currently no screening tests recommended for the general population. However women with a family history of ovarian cancer can have genetic testing. Genetic testing can tell if a woman carries certain gene changes that cause a higher risk of ovarian cancer.

Symptoms

There are few symptoms of ovarian cancer in the early stages. When symptoms do occur, they are usually a result of the cancer growing and causing pressure or pain. Symptoms can include:

• Swelling of the stomach from a build up of fluid
• pain in the abdomen
• digestive problems such as indigestion, long-term stomach pain, bloating, constipation, loss of appetite
• weight loss
• frequent need to urinate
• unusual bleeding from the vagina
• Back or leg pain

Diagnosis

The following are some of the tests that could be done to confirm if ovarian cancer is present.

Imaging Studies

These tests can show whether there is a mass in the pelvis, but they cannot tell if it is cancer.

Ultrasound

This test uses sound waves to create an image on a video screen. Because tumours and normal tissue reflect sound waves differently, this test may be useful in finding tumours and in telling whether a mass is solid or a fluid-filled cyst.

CT scans (computed tomography)

CT scans use an x-ray beam to take a series of pictures of the body from many angles. A computer combines the pictures to form a detailed image. CT scans are useful in showing how large the tumour is, whether lymph nodes are enlarged, and whether the tumour has spread to other organs.

MRI (magnetic resonance imaging)

An MRI displays a cross-sectional picture of the body. The MRI uses radio waves and strong magnets instead of x-rays. MRI scans are helpful in looking at the brain and spinal cord.

Chest x-rays

X-rays may be taken to see if the cancer has spread to the lungs.

Laparoscopy

This method lets the doctor see the ovaries and other pelvic organs. A thin, lighted tube is placed through a small cut (incision) into the lower abdomen.

The only way to tell for certain if a growth in the pelvis is cancer involves a biopsy. A sample of tissue or fluid is removed and looked at under a microscope to see if cancer cells are present. A biopsy is usually done at the time of surgery. The goal of surgery is to obtain tissue samples and to remove all deposits of cancer larger than about 2cms.

Treatment

Treatment depends on the size, location and type of ovarian cancer and how advanced the cancer has become. The most common types of treatments for ovarian cancer are surgery, chemotherapy and radiotherapy, or a combination of these treatments in varying orders.

Surgery

Surgery is the initial treatment for almost all women with ovarian cancer. If all of the tumour can’t be removed, the surgeon might remove as much as possible in a procedure called debulking. Most doctors believe this greatly improves a woman’s chance for survival.

There are several different types of surgery for ovarian cancer.

• Hysterectomy - removing the uterus.
• Unlateral oophorectomy- removing one ovary
• Bilateral oophorectomy - removing both ovaries
• Unilateral salpingectomy - removing one fallopian tube
• Bilateral salpingectomy - removing both fallopian tubes

If both ovaries or the uterus are removed a woman can no longer get pregnant. This surgery will also bring on an early menopause.

Chemotherapy

Chemotherapy is the use of drugs to treat cancer. In most cases of ovarian cancer, chemotherapy is given after surgery. Usually a combination of chemotherapy drugs are given into a vein or by mouth. Once the drugs enter the bloodstream they spread throughout the body. This treatment works well even when the cancer has spread beyond the ovaries. The drugs can also be given directly into the abdomen which targets the drugs right at the cancer cells and limits the amount reaching the rest of the body. This helps reduce side effects.

While chemotherapy drugs kill cancer cells, they also damage some normal cells. The side effects will depend on the type of drugs given, the amount taken, and how long the treatment lasts. Side effects might include the following:

• Nausea and vomiting
• Loss of appetite
• Hair loss
• Hand and foot rashes
• Kidney or nerve damage
• Mouth sores
• An increased chance of infection
• Bleeding or bruising after minor cuts
• Tiredness

Most side effects go away when treatment ends. Hair will grow back, although it may look different. Some side effects, such as menopause and infertility, can be permanent.

Radiation Therapy

Radiation therapy uses high energy x-rays to kill or shrink cancer cells. The radiation may come from outside the body or from radioactive materials placed directly into or near the tumour. Radiotherapy is rarely used in the treatment of early ovarian cancer. Sometimes, radiotherapy is used to help with symptoms that arise as a result of advanced cancers.

Side effects of radiation therapy

Radiation therapy may cause side effects but is generally relatively easy to tolerate. The skin in the area treated may look and feel sunburned. The skin returns to normal within six to 12 months. Many women also feel tiredness, nausea or diarrhoea.

Statistics

World wide

• Each year there are more than 190,000 new cases of ovarian cancer.
• Ovarian cancer accounts for 4% of all cancers diagnosed in woman worldwide.
• The highest rates are in the USA and Northern Europe.
• The lowest rates are in Africa and Asia.
• There are 21,000 cases each year in the USA.

Europe

• Around 61,000 cases occur each year in Europe.
• The lowest rates are in the Southern European countries of Greece, Portugal and Italy.
• The highest are in the Northern European countries of Ireland, Denmark, Finland and the UK.

UK

• Each year around 6,700 women are diagnosed with ovarian cancer.
• More than 4,600 die from ovarian cancer.
• It is the fourth most common cause of cancer death in woman.

Trends

The incidence of ovarian cancer in the UK has been on the rise. This is mainly in women over 65. In women under 65 the rates are relatively stable. It is thought that widespread use of the contraceptive pill could explain the stabilisation in the under 65s.

Survival

Treatment for ovarian cancer has advanced over the last 20 years however long term survival rates have changed very little. Survival is greatly increased if the cancer is detected in the early stages.