Endometrial cancer is the sixth most common cancer among women worldwide and 15th most common cancer, in general. In 2018, over 382,069 new cases were recorded and 89,929 deaths attributed to endometrial cancer worldwide.
Moreover, it is the second most common in the gynecological cancers and is considered as fourth leading cause of death. In fact, the worldwide incidence rate for endometrial cancer is rapidly increasing, and it is estimated to increase by more than 50% by 2040.
Uncontrolled growth of cells in the innermost lining of the uterus (endometrium) is known as uterine/endometrial cancer. It refers to the cancer that starts in the uterus and is different from the cancer of the uterine muscle (sarcoma). It is the most common type of cancer in the uterus. About 2-3% of women may develop it in lifetime, especially during post menopause.
Causes or Risk factors
The exact cause for endometrial cancer is unknown. However, medical experts believe that changes in hormone levels such as estrogen and progesterone may lead to endometrial cancer. Listed below are some of the factors that increase the chance for developing endometrial cancer:
- Early first period
- Starting menopause at a later age
- Irregular menstruation
- Never having given birth
- Older age
- High blood pressure
- Family history of endometrial or colorectal cancer
- Medical history of breast cancer, ovarian cancer or endometrial hyperplasia
- Past pelvic radiation therapy
Signs and symptoms
Early detection of endometrial cancer improves the chances for successful treatment. Majority of women with endometrial cancer have abnormal bleeding that helps in early detection. However, in certain cases endometrial cancers may progress into an advanced stage before causing signs and symptoms.
The symptoms of endometrial cancer may include:
- Abnormal vaginal bleeding between periods or after menopause
- Abnormal vaginal discharge
- Pelvic pain or feeling a mass
- Painful urination
- Pain during sexual intercourse
- Unexplained weight loss
Any symptoms related to endometrial cancer, such as abnormal vaginal bleeding should be informed to the doctor right away, as early diagnosis can improve cancer outcomes. Following are the tests involved in diagnosis of endometrial cancer.
Medical history: The patient’s medical history related to past illnesses and treatments are obtained. Details about the patient’s general health, risk factors (if any) and specific signs related endometrial cancer are analyzed.
Physical examination: Physical examination includes pelvic exam, where the abnormalities in the uterus and cervix, are assessed for.
Other tests and procedures used to diagnose endometrial cancer include:
Ultrasound: During the transvaginal ultrasound, a probe is inserted into the vagina, which creates images of the uterus using high-energy sound. It helps to analyze the thickness and texture of the endometrium. It also enables to check for the presence of abnormalities related to the uterine lining and tumors.
Hysteroscopy: During hysteroscopy, a thin flexible tube with a light source, known as a hysteroscope is inserted into the vagina. It helps to examine the uterus and endometrium for abnormalities. Sometimes, an endometrial biopsy can also be performed during hysteroscopy, where a small tissue sample is obtained from the endometrium and sent for histological analysis. Local anesthesia may be given before the procedure to reduce pain or discomfort during the procedure.
Dilation & curettage (D&C): D&C is recommended when the sample procured during the endometrial biopsy is insufficient or if the biopsy results are unclear. D&C is usually performed as an outpatient procedure under local or general anesthesia. During the procedure, the opening of cervix is dilated (widened) and a curette (spoon-shaped instrument) is used to scrape the tissue from the lining of the uterus and examined under the microscope for abnormal cells.
The histological studies help to confirm the diagnosis and provide details about the grade and type of the endometrial cancer. When the cancer is suspected to have advanced to other body parts, further tests may be recommended that involve determining the extent of spread and cancer stage. They may include chest x-ray, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET).
Endometrial cancer staging
Depending on the size and spread of the tumor, the endometrial cancer is classified into four stages.
- Stage I: The cancer is confined to the uterus.
- Stage II: The cancer has spread to the cervix, but not outside the uterus.
- Stage III: The cancer has spread outside the uterus and cervix, but not beyond the pelvis. It might spread to the fallopian tubes, ovaries, vagina, ligaments of the uterus, and nearby lymph nodes.
- Stage IV: The cancer has spread beyond the pelvis into the bladder, bowel and/or other distant parts of the body.
The treatment plan and the long-term outlook depend on the cancer stage. Endometrial cancer is often diagnosed in earlier stage due to persistent abnormal bleeding. With early diagnosis and prompt medical intervention, endometrial cancer can be treated easily with better outcomes.
The common types of treatments for endometrial cancer include:
Surgery is the most common treatment for endometrial cancer. It involves removing the uterus and other affected areas.
Total hysterectomy: Total hysterectomy involves removing the uterus along with cervix. The surgery can be performed through vagina (vaginal hysterectomy), large incision in the abdomen (total abdominal hysterectomy) or through a small incision in the abdomen (total laparoscopic hysterectomy).
Radical hysterectomy: It involves the surgery to remove the entire uterus along with the immediate ligaments (parametrium and uterosacral ligaments) and upper part of the vagina.
Surgeries that may be performed along with hysterectomy include:
- Salpingo-oophorectomy: It is a surgery to either remove one ovary and fallopian tube (unilateral) or both ovaries and both fallopian tubes (bilateral).
- Lymphadenectomy: It is a surgery to remove one or more lymph nodes from the pelvic region and evaluate it for the presence of cancer.
Radiation therapy uses high-energy beams to destroy the cancer cells, and can be delivered from outside the patient’s body, known as external beam radiation therapy. When the radiation is delivered through a radioactive source placed inside the vagina, it is called as brachytherapy.
In some cases, radiation therapy may be recommended to reduce the chances of cancer recurrence after the surgery. It may also be administered prior to the surgery to shrink the tumor, enabling easy removal. Radiation therapy alone is also used as the treatment for patients who cannot undergo surgery.
Chemotherapy uses anti-cancer drugs to destroy the cancer cells. Many chemotherapy drugs are available and often they are given in combinations. It can be received orally or intravenously, where the drugs enter the blood stream and reach the cancer cells to destroy them (systemic chemotherapy). The drugs can also be placed directly in the body cavity to target the cancer cells in the affected area (regional chemotherapy). Sometimes, chemotherapy may be recommended after the surgery to decrease the risk of cancer recurrence or to shrink the size of the tumor prior surgery. It is often used to treat advanced or recurrent endometrial cancers.
Hormone therapy involves changing the levels of certain hormones in the body. This could impact the cancer cells that depend on such hormones for their growth, thereby arresting their growth. During endometrial cancer, the hormones affected are estrogen and progesterone and the drugs that control these hormones help the cancer cells to shrink and die.
Targeted therapy uses certain drugs to specifically identify and target cancer cells, without affecting normal cells. Monoclonal antibodies, mTOR inhibitors, and signal transduction inhibitors are three types of targeted therapy used to treat endometrial cancer. Often, targeted therapy is used in combination with chemotherapy to treat advanced endometrial cancers.
Immunotherapy helps boost the immune system to recognize and destroy cancer cells. It can be used to treat endometrial cancers that has spread to other parts or when other treatments fail to confer protection.
The endometrial cancer is not preventable; however, certain measures may help to reduce the risk. They include:
- Maintaining healthy weight
- Being physically active
- Using birth control pills
- Discussing with the doctor about the risks of hormone therapy after menopause
- Obtaining appropriate treatment for endometrial problems
The prognosis of the endometrial cancer depends on its type and stage. However, the prognosis for endometrial cancer is usually good due to early diagnosis, as it often leads to abnormal vaginal bleeding. Majority of women with endometrial cancer are successfully cured with surgery. The overall 20 year survival rate is about 80% and the five year survival rate ranges from 74% to 91%. Recurrences are usually expected within the first three years after treatment.
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