About cancer of the uterus

What is cancer of the uterus?

Cancer of the uterus (also called uterine cancer) occurs when cells in any part of the uterus become abnormal, grow out of control and form a lump (tumour). It can be either endometrial cancer (which accounts for about 95% of cancers of the uterus) or the less common uterine sarcoma (which accounts for about 5%).

Endometrial cancer

This cancer begins in the cells in the lining of the uterus (called the endometrium). Endometrial cancer is divided into 4 main subtypes. Knowing these subtypes helps the doctor to work out what, if any, treatment is needed after surgery. Tests on tissue samples collected before or during surgery help the doctor to work out the subtype.

The 4 subtypes are:

• POLE mutant – usually treated with surgery only; often has a good outcome
• mismatch repair deficient (MMRd) – additional treatment like immunotherapy may be needed after surgery; may be inherited (Lynch syndrome)
• p53 abnormal – usually needs treatment after surgery
• no specific molecular profile (NSMP) – may need treatment after surgery.

Uterine sarcoma

These rare soft tissue cancers develop in the cells in the muscle of the uterus (myometrium) or connective tissue (stroma). There are 3 types of uterine sarcoma: endometrial stromal, leiomyosarcoma and undifferentiated.

How common is it?

Each year, about 3400 Australian women are diagnosed with cancer of the uterus, and most are over 50 years of age. Cancer of the uterus is the fifth most common cancer in women and the most commonly diagnosed gynaecological cancer (cancer affecting the female reproductive system).

The number of women diagnosed with cancer of the uterus has increased in recent years, including in younger women. This is likely to be linked to rising rates of obesity and diabetes, as well as more people living to older ages.

Anyone with a uterus can get cancer of the uterus – women, transgender men, non-binary people and people with intersex variations. For information specific to you, speak to your doctor.

The uterus

The uterus, or womb, is where a baby grows during pregnancy. It is part of the female reproductive system, which also includes the ovaries, fallopian tubes, cervix (neck of the uterus), vagina (birth canal) and vulva (external genitals).

Shape and position in the body – The uterus is about the size and shape of a hollow, upside-down pear. It sits low in the abdomen (belly) between the bladder and rectum, and is joined to the vagina by the cervix. The ovaries sit on either side of the uterus. The ovaries contain eggs (ova) and are connected to the uterus by the fallopian tubes.

Layers – The uterus has 2 layers. The myometrium is the outer layer of muscle tissue and makes up most of the uterus. The endometrium is the inner layer or lining.

Menstruation – Each month, from puberty to menopause, the endometrium becomes thicker to prepare for pregnancy. If a pregnancy does not occur, some of the lining is shed and flows out of the body through the vagina. The flow is called a monthly period or menstruation.

Menopause – The hormones oestrogen and progesterone control the release of eggs (ovulation) and the timing of menstruation. As you get older, the ovaries gradually produce less of these hormones. When the levels of oestrogen and progesterone fall low enough, periods become irregular and finally stop. This is known as menopause. After menopause, it is not possible to conceive a child naturally. The uterus also becomes smaller and the endometrium becomes thinner.

The female reproductive system

Other conditions of the uterus

Some conditions can affect the uterus and cause abnormal vaginal bleeding and pain. They may be found during tests for cancer of the uterus.

• Polyps – Small, soft growths attached to the inner wall of the uterus. Polyps are usually benign (not cancer), but some may turn into cancer. They can be removed during a hysteroscopy and tested for cancer.
• Fibroids – Benign tumours that begin in the muscle layer of the uterus (myometrium). Surgery may be used to reduce the size of the fibroid (myomectomy) or remove the uterus (hysterectomy).
• Endometrial hyperplasia – Thickening of the uterus lining (endometrium) caused by too much oestrogen. Usually benign, but can lead to cancer, so may be treated with hormones, minor surgery or, in some cases, hysterectomy.
• Endometriosis – When endometrial tissue grows outside the uterus (e.g. in the abdomen). Does not usually lead to cancer. May be treated with surgery or hormones.

Which health professionals will I see?

Your general practitioner (GP) will arrange the first tests to assess any symptoms. If these tests do not rule out cancer, you will be referred to a gynaecological oncologist or gynaecologist for more tests. If cancer of the uterus is diagnosed, the specialist will consider treatment options. To ensure the best outcome, it is recommended that you are treated by a specialist gynaecological cancer team.

Treatment options will often be discussed with other health professionals at what is known as a multidisciplinary team (MDT) meeting. During and after treatment, you may see a range of health professionals for various aspects of your care (see below).

Health professionals you may see

• gynaecological oncologist – diagnoses and performs surgery for cancers of the female reproductive system (e.g. cancer of the uterus, or cervical, ovarian, vulvar and vaginal cancers)
• gynaecologist – specialises in diseases of the female reproductive system; may diagnose cancer of the uterus and then refer you to a gynaecological oncologist
• radiation oncologist – treats cancer by prescribing and overseeing a course of radiation therapy
• medical oncologist – treats cancer with drug therapies such as chemotherapy, hormone therapy, targeted therapy and immunotherapy (systemic treatment)
• cancer genetics specialist – specialises in understanding cancers that have occurred as a result of inherited risk
• cancer care coordinator – coordinates your care, liaises with other members of the MDT and supports you and your family throughout treatment; care may also be coordinated by a clinical nurse consultant (CNC) or clinical nurse specialist (CNS)
• nurse – administers drugs and provides care, information and support throughout treatment
• fertility specialist – diagnoses, treats and manages infertility; may be an obstetrician, gynaecologist or reproductive endocrinologist
• women’s health physiotherapist – assists with physical problems associated with gynaecological cancers, such as bladder and bowel issues, sexual issues and pelvic pain
• lymphoedema practitioner – educates people about lymphoedema prevention and management, and provides treatment if lymphoedema occurs; often a physiotherapist or occupational therapist
• psychologist, counsellor – help you manage your emotional response to diagnosis and treatment