Definition & Overview
Cancer is identified according to the part of the body that it originates from. When it begins in the uterus, it is referred to as either uterine sarcoma or endometrial carcinoma. The uterus is made up of two parts: the cervix or lower part, and the body or upper part.
The body of the uterus has two main layers: the endometrium and myometrium. The endometrium is the inner layer while the myometrium is the thick outer layer, which is mostly used to deliver a baby. Cancer of the uterus can appear at either the endometrium or myometrium.
When cancer begins at the myometrium, it is referred to as uterine sarcoma. When it originates from the endometrium, it is called endometrial carcinomas or endometrial cancer. The majority of cancers of the uterus originate from the endometrium.
There are six different types of endometrial cancer: adenocarcinoma, small cell carcinoma, squamous cell carcinoma, carcinosarcoma, undifferentiated carcinoma, and transitional carcinoma. These are graded based on the extent of the damage to the endometrium. Grade 1 tumours have at least 95% cancerous tissues forming glands; these cases are not aggressive and they normally spread slowly to other tissues. On the other hand, type 2 cancers (while not too common) are much more aggressive and are likely to affect tissues outside of the uterus. Grade 3 tumours are called high-grade and are highly aggressive.
Cause of Condition
Even though doctors know the characteristics of endometrial cancer, the exact cause of the disease is still unknown. However, just like any other type of cancer, it is certain that it begins with the formation of abnormal cells. Both healthy and abnormal cells will grow, but healthy cells will die at a given time. On the other hand, abnormal cells will continue to grow and form a mass, also referred to as a tumour. When the tumour grows, the cancer begins to affect the nearby tissue and separate from the original tumour to affect other organs, a process called metastasis.
While the exact cause of endometrial cancer has yet to be identified, doctors have outlined several risk factors; these include the following:
Age – Older women have a higher risk of developing endometrial cancer
Diabetes – Endometrial cancer is more common in women with diabetes
Diet & exercise – A high fat diet and lack of exercise increase the risk of developing endometrial cancer
Family history – Women with endometrial cancer usually have relatives with the same condition
Radiation therapy – This type of therapy damages cells, which could result in the development of other types of cancers including endometrial cancer
Endometrial hyperplasia – this condition is described as the increased growth of the endometrium. Most of the time, endometrial hyperplasia simply goes away, but there are cases where the condition leads to the formation of cancer.
Pregnancy – endometrial cancer cases are lower among women who have undergone many pregnancies than in women who have never been pregnant
Obesity – this condition can lead to the excess production of estrogen, which may lead to the development of endometrial cancer
Ovarian tumours – these also increase the production of estrogen, which is suspected to be one of the causes of endometrial cancer
Polycystic ovarian syndrome – this condition leads to abnormal hormone levels, such as higher estrogen.
Ovarian and breast cancer – these types of cancers increase the risk of the formation of endometrial cancers
The most common symptom of endometrial cancer is unexpected bleeding after menopause. However, painful or difficulties in urination, pain during intercourse, pelvic area pain, and bleeding that is not related to menstruation are also signs and symptoms of the disease. It’s important to note that these symptoms are not exclusive to endometrial cancer. Other conditions, such as endometriosis also display the same symptoms.
Who to See & Types of Treatment Available
If you have irregular bleeding or experiencing bleeding after menopause, you should see your family doctor or your gynaecologist. If your doctor suspects endometrial cancer, you will be referred to a cancer specialist for further diagnosis and treatment.
You will first undergo a pelvic examination. During this exam, the doctor will inspect the vulva, uterus, and ovaries. It is likely that the doctor will use a speculum to open your vagina to view your cervix.
To diagnose endometrial cancer, your doctor will examine the endometrium. To do this, a transvaginal ultrasound, hysteroscopy, biopsy, or dilatation and curettage (D&C) will be performed.
A transvaginal ultrasound involves the use of sound wave to create an image of your uterus so the doctor can inspect the image and look for abnormalities. In a hysteroscopy, the doctor examines the inside of the uterus and endometrium by inserting a device called a hysteroscope through the vagina and towards the cervix and uterus. A hysteroscope is a thin flexible tube with a light source at the tip.
A biopsy involves harvesting a small amount of tissue from the uterus. The harvested tissue will then undergo laboratory analysis to check for signs of cancer. If the doctor requires more tissue than a biopsy can provide, D&C will be performed. This procedure involves scraping the lining of the uterus to remove tissue, which will then be examined for cancer cells.
If the tests mentioned above confirm the presence of endometrial cancer, a gynaecologic oncologist will decide on the proper form of treatment. Treatment will be based on the stage of cancer. Endometrial cancer has four stages. Stage 1 is described as cancer that is contained inside the uterus. Stage II is when cancer has not only affected the uterus, but the cervix as well. Stage III is when cancer has spread beyond the uterus. Stage IV is when cancer has spread beyond the pelvic region and has affected the rectum, bladder, or other parts of the body.
Treatment for endometrial cancer includes surgery, radiation therapy, hormone therapy, chemotherapy, or a combination of these procedures.
- Boggess JF, Kilgore JE. Uterine cancer. In: Niederhuber JE, Armitage JO, Doroshow JH, et al., eds. Abeloff's Clinical Oncology. 5th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2013:chap 88.
- Leslie KK, Thiel KW, Goodheart MJ, et al. Endometrial cancer. Obstet Gynecol Clin N Am. 2012; 39:255–268.
- National Cancer Institute: PDQ Endometrial Cancer Treatment. Bethesda, MD: National Cancer Institute. Date last modified: 06/14/2013. Accessed March 5, 2014.
- National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines): Uterine Neoplasms. Version 1.2014. Accessed March 5, 2014.