Endometrial Cancer: The Most Common Gynecological Cancer

Endometrial cancer: What is it? 

Endometrial cancer is cancer of the inner lining (endometrium) of the uterus. The uterus is a female reproductive organ, normally about the size and shape of a medium-sized pear. The uterus is where a fetus grows and develops when a woman is pregnant. The body of the uterus has 2 main layers, the outer thick layer of muscles (myometrium) that is required to push the baby out during childbirth, and the inner lining (endometrium) where it could provide nutrients to the fetus if pregnancy occurs. When cells in the endometrium start to grow out of control and divide uncontrollably, it will eventually lead to endometrial cancer.

Endometrial cancer types

Endometrial cancer can be divided into different types based on how the cells look under the microscope (histological types), such as:

• Adenocarcinoma - the most common subtype of endometrial cancer, it is also the least aggressive type
• Squamous cell carcinoma
• Small cell carcinoma
• Transitional carcinoma
• Serous carcinoma
• Clear-cell carcinoma
• Mucinous adenocarcinoma

Endometrial cancer causes and risk factors

The exact cause of endometrial cancer is unknown, however many risk factors were identified that are strongly linked to this condition. Having a high level of a hormone called estrogen is one of the main factors that can increase the risk of getting endometrial cancer. 

Risk factors of endometrial cancer include:

• Increasing age
• Obesity
• Things that affect hormone levels, such as taking unopposed estrogen after menopause (hormonal replacement therapy) or Tamoxifen (medication used to treat breast cancer)
• Type 2 diabetes
• Endometrial hyperplasia 
• Polycystic ovarian syndrome (PCOS)
• Family history of endometrial cancer
• History of breast, ovarian, or bowel cancer in the past
• History of endometrial hyperplasia in the past 
• Have never given birth (nulliparity) 
• Went through menopause after the age of 55 (late menopause) 
• Had radiotherapy on the pelvis 

Endometrial cancer symptoms and signs 

Endometrial is commonly diagnosed at an earlier stage as most women present with post-menopausal bleeding even at the early stage of the condition.

Symptoms of endometrial cancer may include:

• Bleeding or spotting from the vagina after menopause
• A change to your vaginal discharge 
• Vaginal bleeding between your periods
• Pain in the lower back or between the hip bones (pelvis) 
• Pain during sex 

Endometrial cancer diagnosis 

Endometrial cancer is most often diagnosed after a woman goes to her gynecologist because of her symptoms. After taking a thorough medical history and clinical examination, if the diagnosis of endometrial cancer is suspected or needs to be ruled out, the doctor may do the following tests: 

• Transvaginal Ultrasound (TVUS) - the ultrasound probe will be placed inside the vagina and obtain images of the uterus to check for the presence of a tumor or thickening of the endometrium, which can be a sign of endometrial cancer
• Biopsy - It does not require anesthesia to get a biopsy in the uterus. The doctor will remove a small sample from the endometrium and will send it to the laboratory for further investigation
• Hysteroscopy - during a hysteroscopy, the doctor will insert a thin, flexible tube with lights, through the vagina and cervix into the uterus. It will allow the doctor to have a clear view of the inside of the endometrium, at the same time, the doctor can remove a tissue sample for a biopsy
• Dilatation and curettage (D&C) - A dilatation and curettage procedure requires sedation. The doctor will dilate the cervix, then scrape a certain amount of tissue from the lining of the uterus. The sample will be taken to the laboratory for further examination. This procedure provides a very accurate diagnosis

Further imaging tests may be required if doctors suspect that the cancer is advanced, to look for cancer spread. Which include:

• Chest X-ray
• Computed tomography (CT) 
• Magnetic resonance imaging (MRI)
• Positron emission tomography (PET)
• Cystoscopy and Proctoscopy - a lighted tube will be placed into the bladder (cystoscopy) or the rectum (proctoscopy) to check for local cancer spread

Endometrial cancer staging

Endometrial cancer is classified into four stages:

1. Stage I - cancer is confined to the uterus 
2. Stage II - cancer has spread to the cervix (opening of the uterus)
3. Stage III - cancer has spread to the vagina, ovaries, and/ or lymph nodes, but is still within the pelvis 
4. Stage IV - cancer has spread to the bladder, rectum, or organs located far from the uterus (e.g. lungs or bones) 

Read here to learn more about the stages of endometrial cancer.

Endometrial cancer treatments 

Endometrial cancer is usually treatable when it is found early, the cure rate is high more than 80% in stage I endometrial cancer. Treatment options will depend on the size and location of the cancer, whether it has spread to other parts of the body, and your general health.

Endometrial cancer treatment: Surgery 

Treatment for endometrial cancer usually involves an operation to remove the uterus (hysterectomy), as well as to remove the fallopian tubes and ovaries (salpingo-oophorectomy). During the surgery, the surgeon will also look into the areas around the uterus to look for cancer spread and remove lymph nodes for testing.
 

Endometrial cancer treatment: Radiotherapy 

Radiotherapy uses high-powered radiation beams to destroy cancerous cells. It may be used together with chemotherapy after surgery to destroy remnants of the cancerous tissues that were not removed during surgery. It is useful in preventing recurrence and enhancing the survival rate. 

Endometrial cancer treatment: Chemotherapy

Chemotherapy is an anti-cancer drug injected into a vein or taken orally by mouth, which can kill cancerous cells and stop them from growing and dividing. It can be used before surgery to shrink cancer so that it is more likely to be removed completely during surgery. It is sometimes recommended after surgery to prevent recurrence and enhance the survival rate. 

Chemotherapy can also be used to treat advanced or recurrent endometrial cancer that has spread beyond the uterus. 

Endometrial cancer treatment: Hormone therapy

Hormone therapy may be an option if endometrial cancer has advanced and spread beyond the uterus. It involves taking hormones or hormone-blocking drugs to slow the growth of endometrial cancer cells. The most commonly used hormone medication is a progesterone (e.g. medroxyprogesterone acetate, megestrol).

Endometrial cancer treatment: Targeted therapy

Targeted therapy works by using specific biological molecules to stop the growth of cancerous cells and cut off the tumor cells’ ability to grow and repair themselves. Targeted therapy tends to be used alongside chemotherapy in treatments for endometrial cancers.

Endometrial cancer treatment: Immunotherapy

Immunotherapy is a drug treatment that helps your immune system to fight cancer. Immunotherapy might be considered if endometrial cancer is advanced and other treatments haven’t helped.

Endometrial cancer prevention

Endometrial cancer may be prevented with the following strategies:

• Lose weight if you are overweight or obese
• Regular exercise 
• Ask your doctor about the potential benefits of contraceptives - birth control pills and intrauterine devices have been linked to reduced risk of endometrial cancer. You should consult professional advice and learn about the potential benefits and risks of using these contraceptives