107 Ask the Doctor

What Should I Know About Endometrial Cancer and Radiation Therapy?

Q. I have endometrial cancer. Do I need radiation therapy?

A. The treatment of endometrial cancer often requires a combination of surgery (hysterectomy) and radiation therapy. The need for radiation therapy after a hysterectomy is determined by several factors, such as the grade of the tumor, how deeply it penetrated the inner wall of the uterus, and whether the lymph nodes contain cancer.

Q. What is radiation therapy, and how does it work?

A. Radiation therapy is the use of high-energy radiation beams to destroy cancer cells. It works like regular X-rays do except it uses higher doses of radiation. These powerful rays damage the DNA of cells. Normal, healthy cells, however, are able to repair themselves in a way that cancer cells cannot.

Radiation therapy is referred to as a local treatment, meaning it affects only the body part that is in the intended path of the focused radiation beam. This is in contrast to chemotherapy, which is distributed throughout the body and is therefore referred to as a systemic treatment.

Q. Are there different kinds of radiation therapy?

A. Yes. The most common kind of radiation therapy is known as external beam. External beam radiation is performed by an X-ray machine called a linear accelerator. When you receive treatment for endometrial cancer, the beams are shaped to treat the pelvis and the pelvic lymph nodes. You don’t see or feel the beams. Treatments are typically administered five days a week—Monday through Friday—for five to six weeks.

Internal radiation, also called brachytherapy, is also commonly used when a person needs radiation therapy after she has undergone a hysterectomy. In fact, some women need only brachytherapy and not external beam radiation therapy.

Brachytherapy usually involves the insertion of a smooth, hollow cylinder into the vagina. Via a hollow channel in the cylinder, a radioactive source is introduced and positioned. This procedure delivers a very high dose of radiation therapy to the mucus membranes that line the vagina and very little radiation therapy to the surrounding, healthy organs, such as the rectum and the bladder.

Brachytherapy may also be carried out with a slow-releasing radioactive material, in which case it takes 24 to 72 hours to deliver the necessary radiation dose. This method is called low dose rate brachytherapy. Alternatively, brachytherapy may be performed with a radioactive material that rapidly emits radiation. This treatment usually takes no longer than 20 minutes and is known as high dose rate brachytherapy.

Finally, brachytherapy may be administered in one session or several, depending on the total dose the woman needs to receive. In general, treatments are spaced out to one brachytherapy session per week.

Q. Who are the members of my radiation therapy team?

A. You will meet many specialists during your radiation treatment. A radiation oncologist is a physician who specializes in treating cancer with radiation. He or she leads the team. Radiation oncology nurses help you cope with any side effects that may arise during your course of treatment. Radiation therapists are the highly trained people who deliver the actual daily treatments with the linear accelerator and/or brachytherapy device under the radiation oncologist’s supervision. Medical physicists and dosimetrists work behind the scenes to develop radiation treatment plans according to your doctor’s prescription. You may meet with other healthcare professionals as well.

Q. What can I expect during treatment?

A. Your treatment will involve several stages.

Consulting with a radiation oncologist. Your gynecologist will likely refer you to a radiation oncologist, who will discuss the role of radiation in the treatment of your endometrial cancer. You should ask him or her any questions you have concerning radiation treatment. During that initial visit, you will also likely meet the nurses who will help during your treatment.

Simulation. If you require external beam radiation therapy, the first appointment you will have after you meet your doctor will be the planning session, or simulation. During the simulation you will be positioned on a table exactly as you will be during your actual treatment. It is most common to be positioned on your back. It is also common to lie in a device that ensures you are in the same position for your daily treatments. At the end of the simulation, you will receive several miniature, permanent ink dots, called tattoos, or several temporary lines drawn on your skin with colored markers. These help ensure that you are positioned correctly for treatment each day.

For brachytherapy your radiation oncologist will do some fittings and measurements to determine what size cylinder best fits in your vagina.

Treatment planning. Once the simulation has been completed, the radiation oncologist, physicist, and dosimetrist will plan your treatment using the information obtained during the simulation. The radiation oncologist will write a prescription that outlines exactly how much and where the radiation is to be given and will oversee the plan that the physicist and the dosimetrist design.

First day. For women who undergo external beam radiation therapy, the first appointment after the simulation is a dry run for films only. You lie on the treatment table in the exact position in which you will be treated. No radiation treatment is actually given; the therapist will just take treatment verification films, which confirm that the area being treated is in fact the exact area your doctor intends. Your radiation oncologist must approve the films before the first dose of radiation is given.

Daily treatments. Once the external beam radiation therapy begins, you will be asked to lie on the treatment table, and the radiation therapists will position you correctly. They will then leave the room, and you will receive the treatment. It is important to remain still during the treatments. The sessions are quick and painless. The therapists observe you on a closed-circuit TV monitor and can hear you on an intercom.

For brachytherapy, your radiation oncologist will insert the cylinder into your vagina, and it will be secured in place with a panty. You will lie on a stretcher, where you can read while you receive your treatment.

Weekly status checks. During external beam radiation treatment, you will see your doctor and the nurses weekly. They will check the area that is being treated (pelvis and vagina) and monitor how you are doing. Of course, if you need to see the nurses or doctors more frequently, you may.

Weekly films. Once a week during external beam radiation treatment, films will be taken of the treated area. These are the same type of films you took on the first day. This is a quality-assurance measure; it ensures that the area being treated is exactly the region your doctor intends. Your doctor must approve these films each week for your treatments to continue.

Q. What are the side effects of radiation treatment?

A. There are two kinds of side effects of radiation treatment: those that occur during the course of treatment (acute effects) and those you could potentially get after completing a course of radiation therapy (late effects). The acute effects are very common and include fatigue, abdominal cramping, diarrhea, frequent urination, and vaginal dryness. These symptoms are generally mild and easy to control, and they usually resolve within a few weeks after you complete your treatment. The late effects can occur weeks, months, or even years after treatment is completed. They are much less common and can include problems with organs in the pelvis. Your doctor will discuss all of these before you begin your treatment.

Carol L. Kornmehl, MD, FACRO, is a board-certified radiation oncologist and the medical director of radiation oncology at St. Mary’s Hospital in Passaic, New Jersey. She is the author of the critically acclaimed consumer health book The Best News About Radiation Therapy: How to Cope and Survive (M. Evans, 2004). Dr. Kornmehl is a graduate of the State University of New York at Downstate Medical Center, where she also completed her radiation oncology residency. She is a clinical assistant professor of radiation oncology at Hahnemann University Hospital. Dr. Kornmehl has received multiple honors, including a listing in Who’s Who Among Rising Young Americans, How to Find the Best Doctors: New York Metro Area, the National Registry of Who’s Who, and America’s Registry of Outstanding Professionals. She was elected a fellow of the American College of Radiation Oncology for her exemplary service in the field.

107 Ask the Doctor

Ask the Doctor

What Is Endometrial Cancer?

Q. What is endometrial cancer, and is there a known cause?

A. Endometrial cancer is the most common gynecologic cancer diagnosed in the United States, where approximately 39,080 new cases will be discovered in 2007.1 The cancer forms along the inner lining of the uterus (i.e., the endometrium). Several different types have been described.

In its most common form, endometrial cancer results from obesity. Because there is an obesity crisis in the United States, it is not surprising that so many women are at risk for endometrial cancer. Adipose tissue—the body tissue that stores fat—increases the levels of estrogen hormones in the bloodstream, which then stimulate the endometrial lining to thicken and, in some cases, change into cancer. Women who take estrogen replacement therapy without protection of the progesterone hormone (as well as those breast cancer survivors who are given the drug tamoxifen [Nolvadex®]) are also at risk of developing this form of endometrial cancer. This common type is often very slow growing and can be cured in the majority of patients.

The second main type of endometrial cancer is not associated with obesity and is made of cells that are more aggressive and is therefore more difficult to cure. Uncommon types of endometrial cancer include rare tumors such as endometrial stromal sarcoma and carcinosarcoma, of which less is known.

A small percentage of endometrial cancers are associated with an inherited risk, most notably in patients with a personal or family history of colon cancer.

Q. Are there symptoms or signs of endometrial cancer?

A. Endometrial cancer is often referred to as the “good cancer.” This is because despite the fact that there is no screening test for this cancer, in most cases the signs and the symptoms of the disease will lead to an early diagnosis and, because it is enclosed in the uterus, it is often contained at the time of diagnosis.

Patients with endometrial cancer (or its precancer form called atypical hyperplasia) may report painless vaginal bleeding during the menopausal years. Younger women with endometrial cancer may experience prolonged, heavy menses or bleeding between their periods. In all cases it is very important to discuss these symptoms with your gynecologist so that a careful pelvic examination, a Pap test, and an endometrial biopsy can be performed while the disease is still in the early stages. (It is also important to recognize that a normal Pap test only means that cervical cancer is not causing the bleeding; the Pap test cannot be used to diagnose endometrial cancer.) If an endometrial biopsy is required, the relatively simple procedure will be performed in the doctor’s office and is generally associated with some cramping. (Taking 400 mg of Motrin® [ibuprofen] before the biopsy appointment should ease discomfort.) Only very few patients will need to go to the operating room for a dilatation and curettage (D&C) procedure to make the diagnosis.

Once again, because of where endometrial cancer forms, in most cases it will not have spread outside of the uterus, and patients can be cured. Once your gynecologist has made the diagnosis of endometrial cancer, it is critically important that you are promptly referred to a gynecologic oncologist for consultation regarding treatment options. This consultation is very important to ensure the following:

  • Correct identification of the specific type of endometrial cancer (i.e., the common type associated with obesity as opposed to rare types such as endometrial stromal sarcoma)
  • Selection of the appropriate therapy
  • A detailed discussion regarding the potential early and long-lasting side effects that patients may experience following surgery plus/minus radiation therapy and/or chemotherapy for endometrial cancer

Q. What are the options for treating endometrial cancer?

A. The standard treatment consists of removing the entire uterus (i.e., the body and the cervix), both fallopian tubes, and the ovaries. In medical terminology this is called a total hysterectomy with bilateral salpingoophorectomy. It is important to understand that a total hysterectomy removes the uterus only and that the term hysterectomy has nothing to do with the ovaries, fallopian tubes, or lymph nodes. Some patients may be confused by terms such as partial hysterectomy or radical hysterectomy. Appropriate surgical treatment will also include dissection of the lymph nodes that drain the uterus (and where cancer cells may spread) and a pelvic washing during which a saline solution is poured into the pelvis and then collected to check for any spread of cancer cells within the body cavity.

The entire surgical procedure (hysterectomy; removal of the ovaries, fallopian tubes, and lymph nodes; and pelvic washing) can be performed through an incision on the abdomen, transvaginally with laparoscopic assistance, completely laparoscopically, or using the da Vinci robot. It is very important to discuss the type of procedure with which your surgeon feels most comfortable. In very select cases where a patient is young and feels strongly about being able to carry a child, hormonal therapy may be considered in an effort to avoid hysterectomy. This option applies to very select cases, however, and carries the risk of the cancer spreading if hormonal treatment is not successful.

As discussed in the preceding section, many patients are diagnosed with endometrial cancer when the disease is in its earliest stage (generally, Stage I, in which the cancer has not spread beyond the endometrium and the muscle of the uterus). Because the opportunity for cure is very high in these circumstances, it becomes crucial that the correct treatment is delivered. Sometimes surgery is all that is required. In some patients with a Stage I cancer (as well as those with a Stage II cancer where the tumor has spread to the cervix), a course of radiation therapy may be recommended several weeks after surgery. Those patients who have a Stage III cancer (mainly due to spread to the lymph nodes) or a Stage IV cancer (spread of the tumor into the abdominal cavity or to lymph nodes in the groin) are typically treated with chemotherapy following surgery.

There are several important points that must be emphasized regarding treatment, the most important of which is to understand that the staging of endometrial cancer is based on surgical and pathologic findings (e.g., the status of the lymph nodes), and therefore it is highly advisable that a physician trained to treat endometrial cancer perform the operation. Gynecologic oncologists are the most familiar with the specific lymph node routes through which this disease spreads.

Removing the lymph nodes that drain the uterus does not create problems for the majority of patients, although sometimes lymphedema (leg swelling) can occur if radiation is needed afterward in an effort to prevent the cancer from returning to the pelvis. Once again, a careful discussion with your gynecologic oncologist about potential side effects of therapy will be of great importance before any form of treatment is begun.

The gynecologic oncologist may decide not to dissect the lymph nodes in the following scenarios:

  • When the risk of spread to the lymph nodes is considered to be excessively low based on an evaluation of the uterus while the patient is still in surgery
  • When the medical condition of the patient is so poor that extending the operation to remove the lymph nodes would be risky
  • When a patient’s obesity is so great that technical and safety considerations do not permit a proper lymph node dissection
  • For all of these cases, it is critical that the gynecologic oncologist be present to make the appropriate decisions.

For reasons that are not clear, the survival of patients in the United States with endometrial cancer has not improved in recent decades.2 There has been some speculation that these trends reflect the fact that specialized surgeons are not performing the majority of the procedures due to lack of access to these specialists in rural areas or other impediments.

In one study involving more than 3,500 patients, an association between incomplete surgery and decreased survival was discovered.3 Oftentimes a general gynecologist will remove the uterus, tubes, and ovaries and send the patient to the gynecologic oncologist for a postoperative consultation after the fact. Such cases can become complicated when patients are returned to the operating room for a second surgery to have the lymph nodes removed or when they receive “precautionary” radiation therapy along with the whole host of potential radiation-related side effects as a substitute for not having had their lymph nodes dissected in the first place.

Q. Are there preventive measures I can take to avoid endometrial cancer or to improve my prognosis if I am diagnosed?

A. Preventive measures are always the most effective when there are known causes of diseases. In the case of endometrial cancer, we know that a woman can reduce her risk by engaging in healthy eating and regular exercise to prevent obesity. For those women who will ultimately be diagnosed with endometrial cancer, the earlier it is detected, the better the outlook will be. Any episodes of abnormal bleeding in women of any age—especially in those who have gone through menopause—should be brought to the attention of a gynecologist as quickly as possible so that time is not wasted in receiving the proper evaluation.

Although an estimated 7,400 women are expected to die from endometrial cancer in 2007,1 we expect this number to begin to decline as patient awareness of this disease and appropriate referrals to gynecologic oncologists increase. Much progress has already been made through the cooperative efforts of the Gynecologic Oncology Group, which conducts clinical trials on endometrial cancer biology and therapy in the United States.

References

1.Jemal A, Siegel R, Ward E, Murray T, Xu J, Thun MJ. Cancer statistics, 2007. CA: A Cancer Journal for Clinicians. 2007;57(1):43-66.

2.Beard CM, Hartmann LC, Keeney GL, et al. Endometrial cancer in Olmsted County, MN: Trends in incidence, risk factors, and survival. Annals of Epidemiology. 2000;10(2):97-105.

3.Modesitt SC, Huang B, Shelton BJ, Wyatt S. Endometrial cancer in Kentucky: The impact of age, smoking status, and rural residence. Gynecologic Oncology. 2006;103(1):300-306.

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