1.1 About cancer of corpus uteri
The uterus is composed of two main layers: the inner lining called the endometrium and the outer layer of muscle called the myometrium. Cancer of the corpus uteri, also known as uterine body cancer, refers to uncontrolled growth and malignant transformation of cells within the uterine wall, which can invade surrounding organs and even spread to other parts of the body.
Cancer of corpus uteri (uterine body cancer) is a common cancer in Hong Kong, ranking as the fourth most common cancer among women. Approximately 1,000 new cases are diagnosed each year, and around 100 individuals die from uterine body cancer annually.
Cancer of corpus uteri encompasses different types of cancer, with endometrial cancer accounting for over 90% of cases. If uterine body cancer is diagnosed early and appropriate treatment is administered, the cure rate is quite high. Conversely, if the cancer has already metastasized, the prognosis for the patient is poor.
1.2 Cause of cancer of corpus uteri
The medical community currently does not have a definitive consensus on the exact causes of cancer of corpus uteri (uterine body cancer). However, the following risk factors are known to increase the chances of developing cancer of corpus uteri:
Age
There is a direct correlation between age and cancer of corpus uteri, especially in women over 60 years old, who have a higher risk of developing the disease.
Menstrual History
Since cancer of corpus uteri is closely related to the secretion of female hormones, any factor that increases estrogen levels can potentially raise the risk of uterine cancer. These factors include early onset of menstruation (before the age of 12) or late menopause (after the age of 52). Additionally, women with irregular menstrual cycles also have a higher risk of developing uterine cancer.
Nulliparity
Women who have never given birth have a higher chance of developing cancer of corpus uteri. During pregnancy, the levels of female hormones in the body decrease significantly, resulting in a shorter duration of exposure of the uterus to estrogen. In contrast, women who have never been pregnant are at a higher risk of caner of corpus uteri.
Polycystic Ovarian Syndrome (PCOS)
Patients with PCOS have excessive production of estrogen, which increases the chances of developing cancer of corpus uteri.
Endometrial Hyperplasia
Women with abnormal endometrial hyperplasia have a higher risk of cancer of corpus uteri due to the abnormal thickening of the uterine lining and the potential for cellular abnormalities and even malignancy.
Obesity
Obese women have a higher risk of cancer of corpus uteri compared to the general population, especially those with central obesity after menopause. This is because after menopause, adipose tissue in the body converts androgens to estrogen. Therefore, if there is excessive accumulation of fat, estrogen levels may become relatively high, increasing the risk of cancer of corpus uteri.
Hormone Medications
Prolonged use of hormonal contraceptives or hormone replacement therapy (such as Tamoxifen) after menopause can slightly increase the risk of cancer of corpus uteri.
Family History
If you have immediate relatives who were diagnosed with cancer of corpus uteri, breast cancer, colorectal cancer, or ovarian cancer before the age of 50, your risk of developing cancer of corpus uteri is also higher.
1.3 Symptoms of cancer of corpus uteri
The early symptoms of cancer of corpus uteri(uterine body cancer) are often not obvious, and patients often mistake them for irregular menstrual cycles, leading to delayed diagnosis. As a result, some cases may already be in the advanced stage at the time of diagnosis, making curative treatment impossible. Early detection of suspicious symptoms and seeking medical attention can assist doctors in making an early diagnosis of cancer and providing appropriate treatment, improving the patient’s prognosis.
Common symptoms of cancer of corpus uteri include:
- Postmenopausal vaginal bleeding.
- Abnormal vaginal discharge or discharge with blood after menopause.
- Prolonged and frequent menstrual periods before menopause.
- Irregular or heavy menstrual bleeding.
- Bleeding between periods.
- Lower abdominal or pelvic pain during sexual intercourse.
- Changes in bowel habits.
- Difficult or uncomfortable urination.
- Presence of a lump or swelling in the lower abdomen.
If you experience any of these symptoms, it is important to seek medical attention early to avoid delays in diagnosis and treatment.
1.4 Diagnosis of cancer of corpus uteri
During the initial consultation, the doctor will first inquire about your medical history in detail, including your symptoms, personal medical records, and family history. Then, they will perform a physical examination by palpating your lower abdomen and conducting a gynecological examination, which may involve using a vaginal speculum to examine your vagina and cervix.
Endometrial Biopsy
During the procedure known as endometrial aspiration, the doctor will have you sit on a gynecological examination chair. They will insert a vaginal speculum into your vagina and then gently insert a thin, flexible tube through the vagina into the uterus. A small sample of the uterine lining (endometrium) will be suctioned out and placed under a microscope to diagnose any abnormal uterine cells. This procedure usually takes one to two minutes and may cause slight discomfort.
Transvaginal Ultrasound Scan
A transvaginal ultrasound scan is a non-invasive examination. During the procedure, the doctor will insert an ultrasound probe into the vagina to examine the uterus, fallopian tubes, and ovaries. This provides real-time and clear images that allow the doctor to assess if there is any endometrial hyperplasia (abnormal thickening of the uterine lining).
Hysteroscopy
Hysteroscopy is performed under local or general anesthesia. During the procedure, a thin, flexible tube with a camera at the tip (hysteroscope) is inserted through the vagina and cervix into the uterus. This allows the doctor to examine the uterine cavity for any abnormal tissues. The doctor can also perform a biopsy of suspicious endometrial tissue during this procedure. The obtained tissue sample is examined under a microscope to determine if there are any signs of endometrial cancer.
Dilation and Curettage (D&C)
Dilation and Curettage, also known as D&C, is an accurate method for diagnosing cancer of corpus uteri. This surgery is performed under general anesthesia. During the procedure, the doctor will gently scrape the uterine lining from different parts of the uterus using specialized instruments. The obtained endometrial tissue is then sent for pathological examination to diagnose any abnormal changes in the uterine lining. The surgery usually takes about 10-15 minutes.
1.5 Staging of cancer of corpus uteri
Once cancer of corpus uteri (uterine body cacner) is diagnosed, the doctor needs to determine the staging of the tumor. The purpose of establishing the tumor stage is to develop an appropriate treatment plan for the patient and predict their prognosis.
Currently, the most commonly used staging system is established by the International Federation of Gynecology and Obstetrics (FIGO), using Roman numerals I, II, III, and IV to represent the four stages of cancer.
| I | The tumor is confined to the uterus or endometrium. |
| II | The tumor has spread from the uterus to the cervix but remains within the uterus. |
| III | The tumor has invaded outside the uterus, affecting the ovaries, vagina, or pelvic/para-aortic lymph nodes, with a potential for extensive spread. |
| IV | The tumor has spread to distant organs beyond the pelvic area, such as the bladder, rectum, liver, lungs, bones, or brain. |
Determining the stage of cancer of corpus uteri helps guide treatment decisions and allows healthcare professionals to provide patients with more accurate information about their prognosis.
1.6 Treatment of cancer of corpus uteri
In general, cancer of corpus uteri (uterine cancer) tends to grow slowly and is less likely to spread to tissues outside the uterus. Therefore, the cure rate for early-stage cancer of corpus uteri is quite high, reaching over 90%.
Surgical Treatment – Total Hysterectomy
Surgery is typically aimed at curing the tumor and is suitable for cases where the tumor has not spread.
Total hysterectomy is the most common surgical procedure. It involves removing the entire uterus and cervix. In most cases, the doctor will also remove both fallopian tubes and ovaries (bilateral salpingo-oophorectomy). The removed tissue is sent for pathological examination to determine the type and stage of the tumor.
Total hysterectomy can be performed in the following ways:
Abdominal Hysterectomy
The doctor performs an abdominal surgery to remove the uterus and cervix. This procedure is suitable for patients with larger uterine size, larger tumors, or tumors that are difficult to remove.
Vaginal Hysterectomy
The doctor removes the uterus and cervix through the vagina, without leaving any abdominal incisions. This procedure is suitable for cases where the uterine size is smaller and the tumor is easier to remove.
Laparoscopic Hysterectomy
Also known as minimally invasive surgery, the doctor makes several small incisions in the patient’s abdomen and inserts a laparoscope to visualize the abdominal cavity. Specialized instruments are used to remove the tumor. The advantages of laparoscopic surgery include smaller incisions and faster recovery for the patient.
Radiation Therapy
Radiation therapy, also known as radiotherapy, uses radiation to kill cancer cells and control the tumor. Radiation therapy can be administered in the following ways:
Brachytherapy
The doctor inserts a catheter through the vagina into the uterus and delivers the radiation source through the catheter to provide radiation therapy. The treatment may be performed once or multiple times, and the patient may need to stay in the hospital during the treatment.
External Radiation Therapy
If the tumor has spread to the pelvic area, external radiation therapy is used to control the tumor.
Chemotherapy
Chemotherapy involves the administration of anticancer drugs intravenously to kill cancer cells. Chemotherapy can be used as adjuvant therapy with radiation therapy or surgery to reduce the risk of recurrence. It can also be used to treat advanced-stage or metastatic uterine cancer.