Cervical cancer
Description
An in-depth report on the causes, diagnosis, treatment, and prevention of cervical cancer.
Alternative Names
Dysplasia; Human papillomas virus; Pap smear
Treatment for Invasive Cervical Cancer
Radiation therapy and surgery are about equally effective as a single option for treating very small cervical cancers in their earliest stages, with survival rates of up to 85 - 90% in appropriate patients. Factors influencing the choice between radiation therapy and surgery in women with invasive cancer include the patient's age and health and the extent of the disease. Both surgery and radiation therapy eliminate the possibility of having children in premenopausal women.
Although treatments for cervical cancer have several potentially severe side effects, they are usually well-tolerated. Women undergoing any of these treatments should feel free to seek support groups and counseling, which can be as important for their outlook as medical therapies.
Choosing Between Surgery or Radiation in Early-Stage Cancer
Surgery.
Surgery almost always involves a hysterectomy, an operation that removes the uterus and sometimes other areas in the pelvic region as well. It does not, however, usually impair sexual activity.
In general, surgery is the better choice when small cancers are confined to the cervix in women who wish to remain sexually active.
Radiation.
Radiation treatments to the pelvis often inhibit ovarian function. Early menopause often occurs. Radiation also may cause vaginal scarring. Treatments are available that may reduce these problems and women should not be shy about discussing them with their doctor. Radiation therapy is usually the choice under the following circumstances:
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Cancers have spread beyond the cervix to the pelvis, lower vagina, and urinary tract.
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When certain tumor features indicate a high risk for recurrence after surgery.
Important studies now strongly suggest that when radiation is used along with chemotherapy survival rates improve patients with stages IB to IVA compared to radiation alone. The benefits are greatest in stages I and II.
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Surgery
In the early stages of cervical cancer, surgery is often the preferred primary treatment approach since it preserves normal sexual function. Some patients desiring fertility who have early stage I cancer may be candidates for cervical cone biopsy.
Hysterectomy.
A hysterectomy attempts to eliminate the cancerous tissue by removing the uterus. There are several variations of this operation, depending on the location of the tumor. In women of childbearing age, the ovaries can usually be left intact. Although a woman who has a hysterectomy but retains her ovaries cannot bear children, she will not go into premature menopause. (Studies indicate that leaving the ovaries intact is safe for most women and does not pose any greater risk for cervical cancer recurrence.)
A simple hysterectomy involves the removal of the uterus and the cervix, but leaves the parametrium (tissue surrounding the uterus) and vagina intact. Lymph nodes in the pelvis are not usually removed.
A radical hysterectomy removes not only the uterus and the cervix but also the parametrium, the supporting ligaments, the upper vagina, and some or all of the local lymph nodes (a procedure called lymphadenectomy).
If the cancerous tumor recurs within the pelvis after primary treatment, a more extreme procedure may be performed called a pelvic exenteration, which combines radical hysterectomy with removal of the bladder and rectum. (In such cases, plastic surgery may be needed afterward to recreate an artificial vagina.) Patients undergoing this procedure are physically and psychologically screened in advance to determine whether it is an appropriate choice. The success rate for pelvic exenteration in halting the progression of the disease is approximately 25 - 45%.
Any form of hysterectomy is major surgery and requires at least a 3 - 5 day hospital stay. Although hysterectomy typically uses a wide abdominal incision, less invasive techniques that allow shorter recovery time may be possible for some women with early stage cancers if performed by experienced surgeons.
Side effects include difficulty emptying the bladder or bowels and a painful lower abdomen. Urinary tract infections are very common. Complications include fistulas (abnormal channels within the pelvis, which in this case are a result of surgery), bladder dysfunction, and cysts.
Normal activity, including intercourse, can be resumed in about 4 - 8 weeks. Once the uterus is removed, menstruation will cease. If the ovaries are removed, the symptoms of menopause will begin. These symptoms are likely to be more severe in surgical menopause than in the course of a natural passage to menopause. Hormone replacement therapy should be considered.
Trachelectomy.
An experimental procedure called trachelectomy is being investigated for preserving fertility in certain women in early stage cervical cancer, but it is highly controversial and appropriate in only about 5% of patients. In the procedure, only the cancerous portion of the cervix is removed, while the uterus and the rest of the cervix are left intact. The cervix is closed with a suture.
Small studies suggest trachelectomy may be effective for early stage 1 patients with no risk factors for aggressive cancer. In two studies, conception rates were between 27 - 37%, and survival rates after 2 years were over 95%. The procedure is primarily performed outside the U.S., and few American surgeons are skilled in this surgery at this time. Throughout the world, in fact, only about a few hundred of these procedures have been performed to date. Women should also realize that conception rates are still lower than normal. Even if they can get pregnant, there is a very high risk for miscarriage because the cervix is weakened. Larger and longer-term studies are needed to confirm its long-term safety.
Radiation
Radiation therapy is an alternative approach for early stage cervical cancer. Radiation with concurrent with cisplatin-based chemotherapy is now the standard treatment for locally advanced cervical cancer. Radiation therapy employs high-energy rays aimed at the body from an outside machine (
external beam radiation
) and radioactive materials placed inside the body against the cervix (
intracavitary radiation
).
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External beam radiation
is given first and aimed at the lymph nodes along the pelvic wall. It usually involves a short period of direct-radiation 5 days a week for about 6 weeks in an outpatient setting.
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Intracavitary radiation
(also called
brachytherapy
) follows and is designed to deliver high doses of radiation to the local tumor area. Radioactive material, typically cesium-137, is encapsulated in both gold and platinum. These capsules are inserted in a long stainless steel tube called a tandem, which is inserted in the uterus and in small stainless steel cylinders, called colpostats, which are placed against the cervix as close to the cancerous cells as possible. Commonly, two or more radiation treatments are administered for about 35 hours each time. Radiation implants may also be inserted directly into the tumor using a needle.
In order to be effective, radiation therapy must be powerful enough to destroy the cancer cells' capacity to grow and divide. This means that normal cells are also affected, which may cause significant side effects. Fortunately, healthy cells usually recover quickly from the damage, whereas abnormal cells do not.
Advanced methods for targeting radiation more precisely are now available that limit the damage to healthy tissue. They include 3-D conformal radiation and intensity-modulated radiation therapy (IMRT):
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3-D conformal techniques use computers and a three-dimensional image of the cervix to provide precise targeting of the tumor using multiple high-dose radiation beams.
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IMRT also uses 3-D techniques and employs very thin and precise beam at various intensities.
Side Effects.
Side effects of radiation therapy include fatigue, redness or dryness in the treated area, diarrhea, frequent or uncomfortable urination, and vaginal dryness, itching, or burning. After treatment, side effects usually disappear.
Long-Term Complications.
Complications include proctitis (inflammation of the rectum) and cystitis (inflammation of the bladder). Bowel obstruction is an uncommon complication. Radiation therapy may also cause vaginal scarring, sexual difficulties, and premature menopause in younger women. Occasionally an abnormal tunnel between the bladder and the vagina, known as a vesicovaginal fistula, will develop and may require surgery.
Investigative temporary silicone implants or a noninvasive device called the belly board may protect the small intestine during radiation therapy and help reduce complications.
Radiation itself may increase the risk for later development of cancer in the area surrounding the treated tissue. Although newer more precise radiotherapy approaches should reduce this risk, there is some concern that IMRT may double the incidence of secondary cancers over time compared to 3-D conformal techniques. This is of particular concern in younger patients.
Radiation and Hyperthermia.
Investigators are studying hyperthermia (use of high heat often provided by ultrasound) in combinations with radiation therapy. This approach has shown some promise in achieving significant response rates in small studies. Comparison studies are important to determine if this approach would be as beneficial with radiation therapy as concurrent chemotherapy.
Chemotherapy
Chemotherapy uses cell-killing drugs called
cytotoxic
drugs to destroy widespread cancer cells that have spread from the primary tumor and can no longer be treated with surgery or radiation.
For many years, chemotherapy was only used to reduce symptoms in women with very advanced disease. Today, platinum-based chemotherapy drugs (see below) are being used in many situations for cervical cancer such as:
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In combination with radiation therapy to improve survival rates in certain women, including some with locally advanced cancer.
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In some women with locally advanced cancer to reduce tumors to the point where the cancer may be operable.
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When cancer has spread (metastasized), mostly to reduce symptoms such as pain.
Platinum-Based Drug
s
. The platinum-based drugs cisplatin or carboplatin are often used for treating various stages of cervical cancer. These drugs are usually used in combination with radiation therapy or other chemotherapy drugs. In 2006, the FDA approved a combination of cisplatin and topotecan (another type of chemotherapy drug) for treatment of late-stage cervical cancer in women who are unlikely to be helped by surgery or radiation therapy. Women with stage IVB cervical cancer who received the combination treatment survived around 3 months longer (9.5 months versus 6.5 months) than women who received only cisplatin.
Other drugs.
Other drugs, mostly used in combinations, have also been investigated with some promise. They include with epirubicin, irinotecan, paclitaxel, bleomycin, mitomycin, vinorelbine, gemcitabine, and doxifluridine.
Administration.
Chemotherapy may be given by mouth or as an injection. This may be done at a medical center, doctor's office, or even a patient's home. Some patients receiving chemotherapy may need to remain in the hospital for several days so the effects of the drugs can be monitored. The drugs are often given in cycles with a period of rest following a period of treatment in order to allow a recovery from the side effects.
Side Effects.
Chemotherapy affects all fast-growing cells, including healthy ones. So, side effects are inevitable. Side effects occur with all chemotherapeutic drugs. They are more severe with higher doses and increase over the course of treatment.
Common side effects include the following:
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Nausea and vomiting. Drugs known as serotonin antagonists, especially ondansetron (Zofran), can relieve these side effects in nearly all patients given moderate drugs and in most patients who take more powerful drugs.
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Diarrhea
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Temporary hair loss
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Weight loss
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Fatigue
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Anemia
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Depression
Complications.
Serious short- and long-term complications can also occur and may vary depending on the specific drugs used. They include:
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Increased chance for infection. Chemotherapy suppresses the immune system.
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Severe drop in white blood cell count (
neutropenia
). Certain drugs, such as taxanes, pose a higher risk for this than other chemotherapeutic drugs. White blood cell count may be improved with the addition of a type of drug called granulocyte colony-stimulating factor (either filgrastim or lenograstim).
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Liver and kidney damage.
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Abnormal blood clotting (
thrombocytopenia
).
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Allergic reaction, particularly to platinum-based drugs. (A simple skin test in under investigation that may identify people with a potential allergic response.)
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Menstrual abnormalities. These are common. Premature menopause occurs in about 30% of women, particularly in those over 40.
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Secondary cancers such as leukemia (rare).
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Problems in concentration, motor function, and memory, which may be long-term. Between a quarter and a third of women report such problems. This may be due to a drop in estrogen levels after treatments.
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Review Date: 9/1/2006
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Reviewed By: Harvey Simon, M.D., Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.
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