What is ovarian cancer?

The female reproductive system is made up of several important parts:

  • Ovaries – the organs that store and release a woman’s eggs
  • Womb (also called uterus) – a pear-shaped organ where a baby is carried during pregnancy
  • Fallopian tubes – tubes that link the ovaries to the womb. 

Ovarian cancer is a type of cancer that starts in the cells in and around the ovaries and fallopian tubes. There are many different types of ovarian cancer that are based on the types of cells and tissue that the cancer starts in. [1]

Ovarian cancer is one of the most common cancers in women, with almost 300,000 women being diagnosed worldwide in 2018. [2] It mainly affects women who have already gone through the menopause and half of all ovarian cancers are found in women over 63 years old. [3]

What are the risk factors for ovarian cancer?

The reason that some women get ovarian cancer is not completely clear. However, there are some factors that are known to increase the likelihood of a woman developing this disease, called ‘risk factors’. Having a risk factor does not mean that you will definitely get the disease. Some risk factors identified for ovarian cancer are: [4]

  • Being older than 50 years of age
  • Having gone through the menopause
  • Family history of ovarian cancer
  • Inherited faulty genes (BRCA1/BRCA2)
  • Being overweight
  • Endometriosis – a condition where tissue similar to the lining of the womb is found in other areas, such as the ovaries and fallopian tubes
  • Smoking
  • Diabetes
  • Use of hormone replacement therapy

What are the risk factors for ovarian cancer?

It is difficult to detect ovarian cancer as the symptoms can be mistaken for more common problems such as irritable bowel syndrome (IBS) or pre-menstrual syndrome (PMS). Some of the symptoms to watch out for are: [5]

  • Constant stomach or pelvic pain
  • Constant bloating
  • Difficulty eating/feeling full more quickly
  • Needing to go to the toilet more frequently
  • Back pain
  • Changes in bowel habits (such as diarrhoea or constipation)
  • Extreme tiredness
  • Unexplained weight loss

How is ovarian cancer diagnosed?

If your doctor thinks you might have ovarian cancer, they will do a physical examination and will take a blood test to see if you have high levels of a protein called CA125, [6] which can detect early signs of ovarian cancer. If you have higher levels of the CA125 protein than normal, you may be sent for an ultrasound scan of your abdomen and ovaries to confirm your diagnosis. [6] Once your diagnosis is confirmed, further tests such as biopsies (where a small sample of the cancer is removed) will be performed to help doctors to understand the type, stage and grade of your ovarian cancer (more information on these can be found below). [7]

What are the types of ovarian cancer?

There are several types of ovarian cancer and they look different when viewed under a microscope. This helps doctors to understand what type of cells the cancer is made of, and is sometimes referred to as cancer ‘histology’. There are 3 main types of ovarian cancer: [8]

  • Epithelial – around 90 out of 100 people with ovarian cancer have the epithelial type. It usually occurs in women over 50 and starts in the cells on the outside of the ovaries.
  • Stromal – around 5 out of 100 people with ovarian cancer have the stromal type. It can occur in women of any age and starts in the cells in the core of the ovaries.
  • Germ cell – around 5 out of 100 people with ovarian cancer have the germ cell type. It usually occurs in younger women and starts in the reproductive cells.

What are the stages of ovarian cancer?

The stage of your ovarian cancer describes where the cancer is and how far it has spread into nearby tissues and/or around the body. [7]

  • Stage 1 – the cancer is only in one or both of the ovaries or fallopian tubes and has not spread.
  • Stage 2 – the cancer is in one or both of the ovaries or fallopian tubes and has spread into the pelvis. Areas of the pelvis include the womb, bladder or rectum (back passage).
  • Stage 3 – the cancer has spread outside of the pelvis into the abdomen or lymph nodes at the back of the abdomen.
  • Stage 4 – the cancer has spread outside of the pelvis and abdomen to other organs such as the liver, spleen or lungs.

What are the grades of ovarian cancer?

The grade of your ovarian cancer describes how fast it is likely to grow and spread around the body. [7]


  • Grade 1 – the cancer cells look similar to normal cells and are less likely to spread and come back after treatment.
  • Grade 2 – the cancer cells look different to normal cells and are more likely to spread and come back after treatment.
  • Grade 3 – the cancer cells look very different to normal cells and are the most likely to spread and come back after treatment.

What treatment options are available for ovarian cancer?

The most common treatments for ovarian cancer are surgery (to remove as much of the cancer as possible) and chemotherapy (to kill cancer cells). Treatment will vary based on the type, stage and grade of your ovarian cancer, depending on what is approved in your country. [9]

If you have Stage 1 ovarian cancer you may only need surgery. If you have any other stage of cancer you will likely need to have chemotherapy before and/or after surgery. The treatment you are given will be decided on by your doctor based on all of your medical information.

During your surgery, the surgeons will check whether your cancer has spread so that they know if more treatment will be needed after your surgery. They will then try to remove as much cancer as they can to give you the best possible outcome and reduce the likelihood that your cancer will come back after treatment. This may involve removing some of the reproductive organs, including the ovaries, fallopian tubes, womb and cervix. If your cancer has spread to other organs they will also assess the possibility of removing as much cancer from those organs as possible. [9]

Chemotherapies are drugs that aim to stop cancer cells from growing. You may be given chemotherapy to destroy cancer cells if they cannot be removed with surgery. Chemotherapy may be given as a mixture of drugs as this sometimes works better than one type of chemotherapy on its own. Chemotherapy is given as an infusion into your vein over a few hours. You will need to go to your hospital or clinic regularly to be given chemotherapy treatment, and the exact timing of your visits will be decided by your doctor. [10]  


Depending on the type and stage of your ovarian cancer, and at what point in your treatment you are, you may also be able to have one of the following treatments, depending on what is approved in your country:

  • Targeted therapy - These therapies are able to target specific changes in the cancer cell’s DNA that are causing them to grow out of control. [11]   
  • Hormone therapy - These therapies help to slow or stop the growth of cancer cells by cutting off or lowering the levels of certain hormones in the body. They are usually only used to treat stromal ovarian cancer. [12]
  • Radiotherapy - This treatment is given by aiming x-rays at the cancer to kill the cancer cells. Radiotherapy is only used to treat ovarian cancer in rare cases. [13]

There are new treatments being developed for ovarian cancer. Clinical trials investigate these new drugs and compare them with the current therapies already available. If you would like to know more about clinical trials, or are interested in taking part in a clinical trial, please speak to your doctor or visit the clinical trials page on the Roche ForPatients platform (https://forpatients.roche.com/en/faq/what-is-a-clinical-trial.html).  

What is the outlook for a person with ovarian cancer?

The outlook for ovarian cancer depends on the type, stage and grade of the cancer when it is first diagnosed. [14, 15] Please talk to your doctor about the outlook for your ovarian cancer.

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