Cancer of the uterus is not as common as some of the other cancers of the female reprouctive organs, such as ovarian cancer. However, this does not mean it is any less serious. Uterine cancer affects about 1 in 40 American women at some point in their life. It is more common in older women, after menopause. Over 50,000 new cases of uterine cancer are diagnosed every year in the United States and there are approximately 10,000 deaths due to this cancer.
What Happens In Uterine Cancer?
The most common type of uterine cancer is endometrial cancer. This is where the cancer arises in the inner lining of the uterus known as the endometrium. The other type of uterine cancer known as uterine sarcoma is far less common. Another rarer type of uterine cancer is uterine carcinosarcoma that has characteristics of both endometrial cancer and uterine sarcoma. Therefore the term uterine cancer is often used interchangeably with endometrial cancer. However, it is important to note that endometrial cancer is not the only type of uterine cancer.
Read more on types of uterine cancer.
What causes it?
As with other cancers, there is some change in endometrial cells that cause it to become abnormal. Usually it is due to genetic damage that causes the cell to grow rapidly, be abnormal in shape and structure and invade healthy tissue. This abnormal cell resembles the normal cells, in this case the healthy endometrial cells. This type of growth constituting these abnormal cells are referred to as malignant (cancerous) tumors.
There are a host of risk factors in uterine cancer. These risk factors may cause the genetic damage directly or indirectly increase the chance of uterine cancer forming. High levels of estrogen is one of the main risk factors for uterine cancer along with age. Cigarette smoking, a family history, obesity and various other gynecological conditions like polycystic ovarian syndrome (PCOS) and non-gynecological conditions like diabetes mellitus can also increase the risk of uterine cancer.
Where does the cancer start and spread?
As the cancer continues to invade and destroy healthy endometrial tissue, it may extend deeper into the wall of the uterus. It can eventually infiltrate surrounding organs. In the case of endometrial cancer, the bowel and bladder are at the greatest risk. Some of these cancer cells can also dislodge, enter the bloodstream or lymphatic system and travel to distant sites where it may cause cancer.
However, the cancer starts in the uterus or specifically in the endometrium in uterine or endometrial cancer, respectively. This is set to be the primary tumor. If cancer from elsewhere in the body reaches the uterus and causes cancer there then it is known as a secondary or metastatic cancer. It is important to note that other tumors can occur in the uterus and elsewhere in the body which may not be malignant (cancerous). These non-cancerous growths are referred to as benign tumors.
How To Spot Uterine Cancer
Uterine cancer must be diagnosed by a medical professional and this usually requires diagnostic investigations to confirm the presence of a malignant tumor in the uterus. The signs and symptoms discussed below may occur with several different conditions and is not only seen in uterine cancer. However, when there is abnormal vaginal bleeding in postmenopausal women then uterine cancer must be excluded as 1 in 10 cases of postmenopausal bleeding is due to cancer of the uterus.
One of the characteristic signs of uterine cancer is abnormal vaginal bleeding. This may be seen as heavy periods (menstrual bleeding) or intermenstrual bleeding (bleeding between periods) or spotting in younger women of reproductive age. Blood in the stool or urine may also occur when the cancer spreads.
In postmenopausal women this may be seen as vaginal bleeding which is not normal during this period of life as menstruation has ceased. However, the bleeding is not only spontaneous. It can also occur after intercourse. There may also be a thin vaginal discharge which is stained with blood.
Read more on abnormal vaginal bleeding.
Lower Abominal or Pelvic Pain
Although not as prominent as sign as the abnormal vaginal bleeding, lower abdominal or pelvic pain may also be present in uterine cancer. In younger women, these pains may sometimes be mistaken for ovulation pain or period (menstrual) pain. It can also be incorrectly attributed to other pelvic organs.
However, unlike these sometimes painful events in the menstrual cycle, the uterine cancer pain is usually constant throughout the cycle. The pain may not be limited to the uterus if the cancer spreads to neigboring organs. There may also be pain during defecation as well pain when urinating.
Lump Over the Uterus
Larger tumors may be palpable over the lower abdomen and pelvis where the uterus is located. However, it is important to exclude other possible causes of lumps in these areas and correlate it with more characteristic symptoms. Although uncommonly felt, uterine fibroids may be another reason for feeling a mass in this area. It is important to note that fibroids are usually benign (non-cancerous tumors) and different growths from uterine cancer.
Unintentional Weight Loss
Unintentional weight loss is a common sign in most cancers, irrespective of the location. It is considered a non-specific symptom. This means that it can occur in a host of different conditions, apart from cancers. Unintentional weight loss on its own is therefore not a reliable sign of uterine cancer. However, when considered along with the other signs like abnormal vaginal bleeding then it increases the likelihood of uterine cancer.
Bowel and Bladder Problems
As mentioned, uterine cancer can spread as is the case with all solid cancers. It can spread to distant sites (metastasis) but is more likely to first spread to neigboring organs. Due to its proximity to the uterus, the bladder and bowels (specifically the rectum) are at greatest risk in uterine cancer.
If the cancer spreads to these organs then a host of different symptoms may also be present along with the other uterine cancer symptoms. These symptoms may include:
- Difficulty passing urine
- Pain when urinating
- Bladder pain
- Low volume urine
- Blood in the urine
- Constipation and/or diarrhea
- Painful bowel movements
- Rectal pain
- Blood in the stool