18
Uterine Cancer
IN THIS CHAPTER YOU’LL DISCOVER
→ Uterine (Endometrial) Cancer Staging
→ Treatments for Uterine Cancer
MARY LEONARD WAS 61 and past menopause when, one night after coming home from a meeting, she noticed she was bleeding. “My family history is riddled with cancer. My mother died of uterine cancer when I was young, and when my stepmother (though we didn’t share a gene pool) began suffering repeated episodes of abnormal bleeding, she was diagnosed with uterine cancer as well, so I knew I should call my doctor immediately,” recalls Leonard.
Leonard’s gynecologist, who had treated both her mother and her stepmother, immediately ordered an ultrasound test and when, as expected, he found uterine cancer, he referred her immediately to a gynecologic oncologist. “It turned out to be uterine cancer, and the most aggressive form of it as well,” says Leonard. Her lymph nodes all tested negative, though; the disease hadn’t spread, and her prognosis was good.
“I tell everyone that if you experience a symptom and your gut tells you something is wrong, act immediately. My chance of survival would have been far less if I had waited,” she says.
What Is Uterine Cancer?
Also known as endometrial cancer, uterine cancer is the most common gynecological cancer. It occurs in the uterus — the hollow, pear-shaped organ designed to nourish an unborn baby. The uterus is part of a woman’s reproductive system and is located between the bladder and the rectum. There are many uterine tumors that are benign, but malignant tumors are cancerous and are dangerous because they can spread to other parts of the body.
The vast majority (95 percent) of uterine cancers are known as endometrial carcinomas, because they arise from the endometrial lining of the uterus. A tiny minority (five percent) are sarcomas that arise from the muscle cells. This chapter covers endometrial cancers. Sarcoma cancers that arise in the uterus are treated as sarcomas and are covered in chapter 16.
Statistics
There are approximately 250,000 women who are uterine cancer survivors in the United States. About 50,000 women are diagnosed with uterine cancer each year, making it the fourth most common cancer. It is estimated that 8,200 women will die from the disease, which makes uterine cancer the eighth most common cause of cancer death for women in the United States.
While any woman can develop uterine cancer, certain risk factors increase the probability. The main risk factor is age. Uterine cancer usually occurs in women who are over 60 and past menopause.
Overweight women are more at risk for uterine cancer because fat produces estrogen, the female sex hormone, which is believed to be a contributor to this form of cancer. Eating a high-fat diet is linked to increased risk as well.
Also, while uterine cancer is not directly inherited, it is estimated that one in 10 cases are due to an inherited predisposition to the disease. This includes women with the following characteristics:
- • Women who developed uterine cancer at a younger-than-expected age (less than five percent of cases are diagnosed in women under 40)
- • Those with relatives who developed the disease
- • Women with a history of colon polyps before the age of 40
- • Women who inherited HNPCC (see chapter 8), which is primarily associated with an increased colon and endometrial cancer risk
- • Women with endometrial hyperplasia, which is an overgrowth of cells in the uterine lining
- • Diabetics
- • Breast, colon, and ovarian cancer survivors
- • Cancer survivors who have taken the breast cancer drug tamoxifen (Nolvadex) or who underwent radiation in the pelvic area for other cancers
- • Women who used estrogen alone as a form of hormone replacement therapy
Outcome and Survival Rates
Uterine cancer is among the more curable forms of cancer. The five-year survival rate for a woman with a local uterine cancer at diagnosis is now about 97 percent. If the cancer has spread outside the uterus, but only to the cervix, the rate drops to 69 percent, and then to roughly 60 percent when it spreads to the pelvic area. The five-year survival rate drops to 16 percent if the cancer has spread to the lymph nodes where it can reach more distant organs. However, most uterine cancers are diagnosed well before then.
Types of Uterine Cancer
Adenocarcinoma is the most common form of endometrial cancer. These tumors arise from the glands of the endometrium. They are also referred to as endometrioid adenocarcinoma. As the name denotes, these tumors are made up completely of endometrial cells. There are other, rarer forms of endometrial cancer that are made up of other types of cells or a mixture of cells, but endometrioid adenocarcinomas make up 80 percent of endometrial cancer.
Stages of Uterine (Endometrial) Cancer
As with other forms of cancer, the stage at which it is found predicates its treatment and also its prognosis. These are the stages of endometrial cancer; it is important to remember, though, that there are survivors at every stage of the disease, no matter when it was diagnosed. Also, like other cancers, uterine cancer is categorized according to grade, which is a rating that denotes how slow-growing or aggressive the cancer is believed to be; the higher the grade, the more aggressive the cancer.
STAGE I
The cancer is found in the uterus only. The survival rate for this earlier stage of cancer is 90 percent.
STAGE II
Endometrial cancer cells are found in the connective tissue of the cervix (the narrow opening that connects the uterus to the vagina), but the cancer has not spread outside that organ.
STAGE III
The cancer has spread throughout the uterus and the cervix, and may also have spread to other organs in the reproductive system, including the fallopian tubes, the ovaries, and the vagina, but it has not spread outside the pelvic region.
STAGE IV
The cancer has spread beyond the pelvis to the abdomen and the lymph nodes in the groin, from which it can spread to distant parts of the body as well.
“The outcome for cancers that are caught in the early stage and are of low-grade (meaning non-aggressive) has been fairly excellent all along. But we are also doing better with the more aggressive cancers that are more likely to recur,” says Dr. Peter Frederick, gynecologic oncologist and the director of minimally invasive surgery for such cancers at Roswell Park Cancer Institute in Buffalo, New York.
About 70 percent of such recurrences happen within three years of the initial treatment. Symptoms may be similar to the initial appearance of uterine cancer.
One of the most important factors in the treatment of endometrial cancer is accurate staging of the tumor. But this is not easy, because imaging tests done prior to surgery do not give complete information, and the only way to definitively stage the tumor is after surgery, says Dr. Frederick. “For those cases where staging of cancer is appropriate, it’s very important to accurately stage a uterine cancer, because if the patient undergoes inappropriate or incomplete surgery, she may be undertreated and need a second operation, or overtreated and subjected to unnecessary radiation.”
Signs and Symptoms
- • Abnormal bleeding after menopause
- • Pain during sexual intercourse
- • Difficult or painful urination
- • Pain in the pelvis
An abnormal, blood-streaked discharge from the vagina is the most common symptom of uterine cancer.
Specific Diagnostic Tests
The following section describes the tests that are specifically performed to diagnose uterine cancer. They may be done in addition to general cancer diagnostic testing. See chapter 2 for more information.
PELVIC EXAMINATION
The doctor feels the uterus, vagina, ovaries, fallopian tubes, bladder, and rectum to check for any unusual changes. A Pap test may also be done. This test is not done to diagnose uterine cancer, but may find abnormal glandular cells caused by it.
TRANSVAGINAL ULTRASOUND
This test utilizes a wand-like instrument placed in the vagina that emits sound waves to produce an image of the organs of the reproductive system.
OTHER IMAGING TESTS
X-ray, CT scans, PET scans, and MRI scans may be used to show any tumors or abnormalities.
ENDOMETRIAL BIOPSY
The doctor inserts a small tube into the uterus through the cervix and, using suction, removes a small sample of tissue that is then studied under the microscope.
HYSTEROSCOPY
The doctor uses a thin, lighted tube, called a hysteroscope, to examine the inside of the uterus.
D&C
Formally known as “dilation and curettage,” this procedure, like a biopsy, also removes cellular tissue for examination. It is often performed in combination with a hysteroscopy, allowing the doctor to view the lining of the uterus during the procedure. Once uterine tissue has been removed either during a biopsy or D&C, the sample is checked for cancer cells.
LYMPHADENECTOMY
This surgery to remove the lymph nodes is done to definitively determine the exact stage and aggressiveness of the uterine cancer. It is done if cancer cells were found in the lymph nodes or at the same time as a hysterectomy.
The necessity of this procedure is controversial. Some doctors recommend it be done for all cases of uterine cancer, including the apparently localized, earlier stages to help determine the need for additional therapy after surgery, while others reserve it for patients with more advanced disease. In any case, this is major surgery that carries with it the risk of side effects, so whether to undergo this procedure is an important decision. Again, those diagnosed with uterine cancer should be treated by a gynecologic oncologist, who will best determine the need for this procedure.
Treatments
The protocol for addressing uterine cancer depends on whether the cancer is caught while in an early stage, or at a later state when it has spread beyond the uterus. In most cases, uterine cancer is initially treated with surgery, and the type depends on the stage of the cancer. Radiation, chemotherapy, hormone therapy, or a combination of these may be used as a course of treatment.
SURGERY
This is the initial treatment for uterine cancer. Depending on the stage of the cancer, the surgeon will perform either a simple hysterectomy (removal of the uterus and cervix), or a radical hysterectomy (removal of the uterus, cervix, the upper part of the vagina and the surrounding area). A bilateral salpingo-oophorectomy (removal of both fallopian tubes and ovaries) as well as the removal of lymph nodes is also usually performed.
“The cornerstone of treatment for uterine cancer is a hysterectomy, with removal of the uterus and cervix, both ovaries, and the fallopian tubes,” says Dr. Frederick. Chemotherapy and/or radiation are also used to treat local uterine cancers that are more aggressive, or those that have spread. “Radiation or hormone therapy may be preferable to surgery for women who are elderly or frail,” he adds.
Minimally to moderately invasive techniques include laparoscopic surgery, being performed through several very small incisions, with abdominal surgery requiring an incision measuring about five inches.
RADIATION
High-energy radiation kills cancer cells by damaging their ability to multiply. There are two types of radiation that can be used to treat uterine cancer. External-beam radiation therapy delivers treatment from a machine outside the body. Brachytherapy delivers treatments by using radioactive sources that are placed into the vagina, uterus and/or surrounding tissues to kill the cancer cells. See chapter 3 for more information on radiation.
CHEMOTHERAPY
As with many other forms of cancer, chemotherapy can be used to treat uterine cancer after surgery to make sure that all the cancer cells have been eradicated or in more advanced stages of cancer as well. Chemotherapy can also render a woman infertile or induce early menopause. See chapter 3 for more information.
HORMONE THERAPY
This method is used to slow the growth of uterine cancer cells. Hormone therapy for uterine cancer involves the sex hormone progesterone, administered in pill form. Hormone therapy may be used for women who cannot have surgery or radiation therapy, or in combination with other types of treatment. Side effects of hormone therapy include fluid retention, increase in appetite, and weight gain. Women in their childbearing years may have changes in their menstrual cycle.