Decorative image

Teratoma of the ovary

Ovarian teratoma is a type of germ cell tumour. Cancerous teratomas are rare, and usually affect girls and young women up to their early 20s.

Germ cell tumours begin in egg cells in women or sperm cells in men. There are 2 main types of ovarian teratoma:

  • mature teratoma, which is non cancerous (benign)
  • immature teratoma, which is cancerous

Types of teratoma

Mature teratoma

The mature teratoma is the most common type of ovarian germ cell tumour. It is most often diagnosed in women during their reproductive years (from teens to forties).

Mature teratoma is often called a dermoid cyst. It is removed with surgery and the condition is then cured.

Immature teratomas

Immature teratomas are usually diagnosed in girls and young women up to their early 20s. These cancers are rare. They are called immature because the cancer cells are at a very early stage of development.

Most immature teratomas of the ovary are cured, even if they are diagnosed at an advanced stage.

Grading and staging ovarian teratoma

The grade and stage of your cancer is very important because they help your specialist to decide what treatment you need. The grade describes how the cells look under a microscope.

The less developed the cells look, the higher the grade. Higher grade cancers grow more quickly than low grade.

There are 3 different grades of immature teratoma. Generally, grade 1 teratomas are the slowest growing and least likely to spread.

The stage of a cancer tells you how far it has grown. In ovarian teratoma there are 4 stages, from 1 to 4:

  • stage 1 means the cancer is only in the ovary (or both ovaries)
  • stage 2 means the cancer has spread into the fallopian tube, womb, or elsewhere in the area circled by your hip bones (your pelvis)
  • stage 3 means the cancer has spread to the lymph nodes or to the tissues lining the abdomen (called the peritoneum)
  • stage 4 means the cancer has spread to another body organ some distance away, for example the lungs

Treating ovarian teratoma

Surgery and chemotherapy are the treatments doctors most often use for immature teratoma of the ovary.


During your surgery, the surgeon (gynaecological oncologist) will remove the affected ovary but your other ovary will be left. As most women with ovarian teratoma are young, doctors are aware that they may want to have children in the future and so will remove as little tissue as possible.

During the operation, the surgeon examines the inside of your abdomen and your abdominal organs for signs of cancer. They may take biopsies and send them to the lab to look for cancer cells. Your surgeon will also wash out the inside of your abdomen and send the fluid to be checked for cancer cells. This all helps to make absolutely sure that the cancer hasn't spread.

If you have a grade 1 immature teratoma that has not spread outside the ovary (stage 1) then surgery is likely to cure it and you may not need chemotherapy.

If your cancer has spread beyond the ovary, your surgeon will remove some or all of the tumour, depending on where it is.  It is not uncommon to have tumour left behind.


You have chemotherapy once you have recovered from your surgery. If there is any cancer left after you have had chemotherapy, you may have more surgery to remove it then. Immature teratomas of the ovary can often be cured with a combination of surgery and chemotherapy, even if they have spread when they are diagnosed.

Your exact treatment is decided by your own specialist, but the most common combination of drugs used is BEP - bleomycin, etoposide and cisplatin. Doctors use this combination because it is very good at preventing the teratoma from coming back. 

You have this type of chemotherapy as several cycles of treatment. Each cycle lasts 3 weeks. You have several days of chemotherapy at the beginning of the cycle and then a break until the start of the next cycle.

The chemotherapy doctors use for ovarian teratoma does not usually affect your fertility. Women frequently have successful pregnancies after they have had this type of treatment.

Coping with teratoma of the ovary

Coping with a diagnosis of cancer can be difficult, both practically and emotionally. It can be especially difficult if you have a rare cancer. Being well informed about your cancer and its treatment can make it easier to make decisions and cope with what happens.

Talking to other people who have the same thing can help. But it can be hard to find people who have had a rare type of cancer.

Cancer Research UK’s discussion forum is a place for anyone affected by cancer. You can share experiences, stories and information with other people who know what you are going through.

Or contact the Rare Cancer Alliance who offer support and information to people who have rare cancers.

Research and clinical trials

There may be fewer clinical trials for rare types of cancer than for more common types.

It is hard to organise and run trials for rare cancers. Getting enough patients is critical to the success of a trial. The results won't be strong enough to prove that one type of treatment is better than another if the trial is too small.

The International Rare Cancers Initiative (IRCI) aims to develop more research into new treatments for rare cancers. They are designing trials that involve several countries so that more people will be available to enter trials.

Follow up

After you've finished your treatment, your specialist will see you regularly.

When you were first diagnosed, you would have had blood tests that may have shown up chemicals released by the cancer cells. These are called markers. The markers produced by most immature teratomas are called HCG and AFP.

Not everyone with a teratoma has raised markers. But if you did when you were diagnosed, your specialist can use them to monitor your health at your follow up appointments. If they show up in your blood test, this could mean that the cancer has come back. 

At your follow up appointments, your specialist will also examine you and ask how you are feeling. You may have CT scans from time to time, but not everyone needs these.

Last reviewed: 
21 Dec 2018
  • Textbook of Uncommon Cancer (4th edition)
    D Raghavan, C Blanke, D Johnson and others
    Wiley-Blackwell, 2012

  • Cancer and its management (7th edition)
    J Tobias and D Hochhauser
    Wiley-Blackwell, 2015

Information and help

Dangoor sponsorship

About Cancer generously supported by Dangoor Education since 2010.