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AmMed Cancer Center > Treatment Information by Cancer Type > Cervical Cancer

Cervical Cancer

Cancer Information :

Cervical Cancer

The Hong Kong Cancer register estimates that nearly 400 women will be diagnosed with cervical cancer in 2007. At one time, cervical cancer was considered one of the most deadly cancers for women. Thanks to effective screening, which can detect cervical precancers and cancers early, most cases of cervical cancer can be cured.
 
With the advent of widespread screening by a vaginal smear test developed by George Papanicolaou in the 1950s (commonly known as the "Pap smear"), the number of deaths from cervical cancer has fallen dramatically -- from more than 35,000 per year to less than 4,000 per year today.
 
The most significant risk factor for cervical cancer is infection with the human papillomavirus (HPV), which can be transmitted during sex. For more information about ways to prevent HPV and cervical cancer, see the Risk Factors & Prevention section of this overview.
 
A Slow-Growing, Treatable Cancer
Cervical cancer is cancer of the cervix -- the lower part of the uterus that extends into the upper end of the vagina. The majority of cervical cancers begin where the inner part of the cervix closest to the uterus (the endocervix) meets the outer part of the cervix closest to the vagina (the ectocervix). This area is called the "transformation zone."
 
Cervical cancer usually grows slowly over many years. Before true cancer cells develop, the tissues of the cervix undergo changes at the cellular level -- called dysplasia, or precancers -- that a pathologist can detect in a Pap smear. These changes range from mild dysplasia or cervical intraepithelial neoplasia (CIN1) to moderate (CIN2) to severe (CIN3), which is also known as carcinoma in situ (an early type of cancer that has not spread to nearby tissues and only involves cells in the tissue where it originated).
 
If left untreated, these precancers have the propensity to spread deeper into the tissue and become cancerous. Once they spread beyond the borders of the cervix, they can invade more deeply into tissues in the vagina, rectum, or bladder, and ultimately metastasize to other parts of the body.
 
Types of Cervical Cancer
There are two main types of cervical cancer:
 
·         Squamous Cell Carcinoma
The majority of cervical cancers -- 80 to 90 percent -- are squamous cell carcinomas. These cancers originate in the squamous cells, which are the thin, flat cells that cover the surface of the ectocervix. The majority of cervical cancers begin where the endocervix and the ectocervix meet.
 
·         Adenocarcinoma
Ten to 20 percent of cervical cancers are adenocarcinomas, which are those cancers that begin in the gland-like cells that line the endocervix.
 
Cancers that have features of both cell types are known as mixed, or adenosquamous, carcinomas.
 
Risk and Prevention
 
The most significant risk factor for cervical cancer is infection with human papillomavirus (HPV). Researchers now believe that more than 90 percent of cervical cancers are caused by HPV, a commonly occurring virus that will infect more than two-thirds of all sexually active women within their lifetimes.
 
For more than two decades it has been known that papillomaviruses can cause cervical dysplasia, or precancers. More recently, DNA from these viruses has been found to exist in virtually all cervical squamous cell carcinomas (the most common type of cervical cancer).
 
Other risk factors for cervical cancer include:
  • early age at first sexual intercourse
  • having many sexual partners
  • giving birth to many children
  • smoking cigarettes (which produces chemicals that can damage cervical cells, making them more vulnerable to infection and cancer)
  • using oral contraceptives
  • infection with HIV (which reduces the body's ability to fight off HPV infection and early cancers)
By avoiding these known risk factors for HPV infection, women can reduce their likelihood of developing cervical cancer. Women without these risk factors rarely develop cervical cancer.
 
According to the American Cancer Society, although all women can help protect themselves from HIV and other sexually transmitted diseases by having their partners use condoms, condoms do not provide complete protection from HPV. Using condoms probably reduces the rate of infection by about 70 percent. This is because HPV (unlike HIV) can be spread by physical contact with any infected area of the body.
 
Importance of the Pap Test & Additional Testing
The Pap test can detect HPV infection and precancers years before cervical cancer develops. Our doctors recommend that women have their first cervical cancer screening about three years after their first sexual intercourse or by the age of 18 -- whichever comes first.
 
If a woman has an ambiguous or positive Pap test, an HPV-DNA test (Digene® HPV Test) is performed to identify the presence of any of the 13 high-risk types of HPV associated with the development of cervical cancer. The test can detect these high-risk types of HPV even before there are any visible changes to the cervical cells. The role and usefulness of HPV testing as an alternative or additional test to primary Pap screening continues to evolve.
 
Treatment of these conditions can halt invasive cancer before it starts.
 
HPV Vaccines
While the vast majority of sexually transmitted HPV infections are harmless and disappear without treatment, certain high-risk strains of the virus that persist in the body may develop into cervical cancer or genital warts (warts that typically appear around the genitals or anus). Because of the strong connection between HPV and cervical cancer, scientists are working to develop vaccines to target the virus strands most likely to turn into cancer.
 
The first of these vaccines approved by the FDA is Gardasil®, or quadrivalent human papillomavirus (types 6, 11, 16, 18) recombinant vaccine. The vaccine specifically targets HPV types 16 and 18 (which cause about 70 percent of cervical cancer cases) and types 6 and 11 (which cause approximately 90 percent of genital wart cases).
 
This vaccine can only be used to prevent an HPV infection and is not meant for women who already have an infection. Additional studies are underway to identify vaccines that target other types of HPV, for men and women who already have HPV and for women with advanced or recurrent cervical cancer.
 
Women interested in learning more about these vaccines and ongoing clinical trials should contact their physician. Information about clinical trials is available from the NCI's Cancer Information Service and ClinicalTrials.gov (maintained by the National Institutes of Health).
 
Screen and suillivance
 
Our Cervical Cancer Screening Guidelines
First Screening
Our doctors recommend that women have their first cervical cancer screening about three years after their first sexual intercourse or by the age of 18 -- whichever comes first.
 
Women Up to Age 30
For women up to the age of 30 years old, our doctors recommend annual cervical cytology testing (which can include Pap smears or liquid-based cytology).
 
Women 30 Years and Older
For women 30 years old and older, our doctors recommend one of the following three screening options:
  • Annual cervical cytology testing (which can include Pap smears or liquid-based cytology)
  • Cytology testing every two to three years for women who have had three consecutive negative or satisfactory annual cytology tests
  • Cytology plus HPV-DNA testing to screen for any of the 13 high-risk types of HPV associated with the development of cervical cancer. If both the cytology and the DNA tests are negative, screening should occur every three years.
Immunocompromised Women of Any Age
In addition, women of any age who are immunocompromised -- as the result of organ transplantation, HIV infection, or cancer chemotherapy -- and treated with steroids, or who were exposed in utero to an estrogen drug known as diethylstilbestrol (DES), should be screened annually with either Pap smear or liquid-based cytology. (From 1938 to 1971, DES was prescribed to some pregnant women to prevent miscarriage. The female children of these women have an increased risk of a rare cervical and vaginal cancer.)
 
Pap Test
The Pap test is an effective method of screening for cervical cancer. The results can show the presence of the common virus HPV, which causes 90 percent of cervical cancer. By avoiding contact with HPV infection, women can also reduce their likelihood of developing cervical cancer.
 
Symptom
 
Cervical cancer, especially in its earliest stages, often causes no symptoms. That is why it is very important to see your doctor for regular screening.
 
When symptoms do occur, they may include the following:
  • pain or bleeding during or after intercourse, douching, or following a pelvic examination
  • pelvic pain
  • unusual discharge from the vagina
  • blood spots or light bleeding other than a normal period
These symptoms can be caused by cervical cancer, or by a number of serious conditions, and should be evaluated promptly by a medical professional.
 
Diagnosis
 
To diagnose cervical cancer, the most commonly used method is the Pap test.
 
 
Pap Test
A Pap test is most commonly used to screen for and detect the possibility of a cervical cancer or dysplasia (precancer).
During a Pap test, the doctor first inserts a lubricated instrument (called a speculum) into the vagina to enlarge the opening. The doctor then takes a sample of mucus and cells by gently scraping the cervix. This test is not painful; some patients report just a few seconds of minor discomfort.
The cells obtained from the Pap smear are sent to a lab to be analyzed under a microscope. Collection, sampling, screening, and interpretation of Pap smears all require considerable experience and skill to ensure an accurate diagnosis.
 
Colposcopy & Biopsy
If an abnormality is found during a Pap test, a gynecologist may perform a colposcopy, which is the examination of the cervix using a colposcope (a lighted magnifying instrument attached to magnifying binoculars). A gynecologist may also perform a biopsy by removing a tiny section of the surface of the cervix for microscopic examination. A pathologist will examine the sample to see if it contains precancer or cancer cells.
 
Cone Biopsy or Conization
If abnormal cells are found or if diagnosis is not clear after a colposcopy, a surgeon may remove a slightly larger, cone-shaped piece of tissue (called a cone biopsy or conization). At Memorial Sloan-Kettering, cone biopsies are often performed with a loop electrosurgical excision procedure (LEEP), in which an electrical current is passed through a thin wire loop to remove the sample tissue. LEEP takes only about ten minutes under local anesthetic and can be performed in the doctor's office. The cone biopsy can also serve as a method of treatment, completely removing many precancers and early cancers. More than 90 percent of cervical cancers can be halted with this technique without further treatment.
 
Imaging Tests
If your doctor suspects that the cancer may have spread beyond the cervix, you may have a chest x-ray, computed tomography (CT) scan of the abdomen and pelvis to check for metastatic disease, and/or magnetic resonance imaging (MRI) scan to determine the extent of local disease.
 
AmMed Cancer Canter radiologists have established the value of pelvic MRI in determining the extent of local involvement in a patient's cervical cancer. We have also been assessing the utility of the positron emission tomography (PET) scan as a means of determining if cancer has spread. [PubMed]
 
Treatment
 
The primary forms of treatment are surgery and combined radiation therapy and chemotherapy.
 
Options for treating cervical cancer depend chiefly on the stage of disease -- the size of the tumor, the depth of invasion, and whether the cancer has spread to other parts of the body. Other factors that are considered are the patient's age and if she wishes to have children.
 
Carcinoma In Situ
These cancers are preinvasive and can be treated conservatively. In most cases, it is possible to spare the uterus. Options for treatment include:
  • cone biopsy, or conization (to surgically remove a cone-shaped piece of tissue containing the cancer); this procedure is generally used for diagnosis and treatment
  • internal radiation therapy, or high-dose brachytherapy (for women unable to have surgery)
  • total, or complete, hysterectomy (surgery to remove the entire uterus, including some or all of the cervix)
These treatments are almost always effective in removing precancers and stopping them from developing into true cancers.
 
Early Cervical Cancer (Stages I-IIA)
For early cervical cancers that are confined to the cervix, surgical options may include hysterectomy (removal of the uterus), sometimes encompassing the tissue next to the uterus and cervix. Lymph nodes from the pelvis may also be removed and examined for cancer cells.
 
If the cancer is associated with "high-risk" features -- such as involvement of the pelvic lymph nodes, invasion of the lymph channels or blood vessels of the cervix, or involvement of the tissue along the uterus -- doctor will usually recommend chemotherapy combined with radiation therapy.
 
For women whose cancer is confined to the cervix and who wish to have children,surgeons may be able to remove just the cervical tissue and spare the womb (the upper part of the uterus known as the fundus) through a procedure known as radical trachelectomy. This procedure has the potential to preserve a woman's ability to bear children. Using either laparoscopy or "open," traditional surgery, the surgeon removes the cervix and pelvic lymph nodes. If they are free of cancer cells, only a portion of the cervix needs to be removed, rather than the entire uterus. If the patient becomes pregnant, she is still able to have a full-term pregnancy and deliver the baby by cesarean section.
 
For very large cancers of the cervix without evidence of spread beyond the cervix, treatment may include either chemotherapy and radiation therapy or radical hysterectomy. A few clinical studies have demonstrated that primary treatment with chemotherapy and radiation improved the survival of patients with these cancers compared to radiation therapy alone.
 
Sentinel Lymph Node Biopsy
At AmMedCancerCenter, we are currently evaluating an approach -- called sentinel lymph node biopsy -- that could eliminate the need to remove all the pelvic lymph nodes for analysis. Using a blue dye and a special radioactive substance that can be traced with imaging techniques, doctors can identify during surgery the first lymph node (the sentinel node) to which cancer cells would travel after leaving the cervix. This technique is called intraoperative lymphatic mapping or sentinel node mapping. If this node is free of cancer cells, the goal is to avoid removing additional lymph nodes. If the node does contain cancer cells, the surgeon then removes additional lymph nodes for further examination.
 
Sentinel node mapping may help prevent the unnecessary removal of lymph nodes in some women, leaving these nodes in place to continue their normal functions of draining fluids and fighting infection.
 
Brachytherapy
At AmMed, we have vast clinical experience in combined modality therapy (combination chemotherapy and radiation therapy), including brachytherapy. In high-dose brachytherapy, radioactive material is applied directly to the tumor. Brachytherapy is used in combination with external beam radiotherapy, in which high-energy rays are aimed at the cancer.
 
Advanced Cervical Cancer (Stages IIB-IVA)
If cervical cancer has spread beyond the cervix and into the surrounding pelvic tissues, surgery alone is usually not an effective cure. Patients with this degree of invasive cancer have traditionally also been treated with radiation therapy (the use of x-rays or other high-energy waves to kill cancer cells and shrink tumors), either alone or in addition to surgery.
 
In recent years, however, there has been a major shift in the treatment of advanced cervical cancer. Based on the results of large clinical trials, the standard of care for regionally advanced cervical cancer is now chemotherapy combined with radiation therapy. The radiation therapy may be delivered externally and/or internally through brachytherapy (by applying radioactive material directly to the cervix).
 
When chemotherapy drugs (such as cisplatin and 5-fluorouracil) are given with radiation therapy, the tumors are made more sensitive to the effects of the radiation. This combined action improves the survival of advanced cervical patients dramatically -- by as much as 30 to 50 percent. Nearly all patients with invasive cervical cancer can benefit from this combination of radiation therapy and chemotherapy.
 
Stage IVB & Recurrent Cervical Cancer
For women whose cancer spreads beyond the pelvis (into the lungs or liver, for example) or who have recurrent disease, treatment is aimed at reducing cancer-related symptoms in order to improve a patient's quality of life, and hopefully to prolong her survival.
 
Chemotherapy is the primary modality of treatment for these patients, and several drugs, such as cisplatin and paclitaxel, are available. Treatment of this group of women -- with a focus on new anticancer drugs and combinations of drugs -- remains a major research priority at MemorialSloan-KetteringCancerCenter.
 
Some women with recurrent cervical cancer may choose an extensive surgery known as pelvic exenteration that requires Memorial Sloan-Kettering's gynecologic surgeons to remove cancerous tissue and reconstruct the remaining organs so the patient retains optimal function. This is an extremely radical procedure reserved for patients with limited treatment options.
Pelvic exenteration may be combined with intraoperative brachytherapy, which is only performed at hospitals such as Memorial Sloan-Kettering.
 
Because this procedure is physically and emotionally demanding, investigators at Memorial Sloan-Kettering have initiated a trial to learn more about the physical, emotional, educational, and sexual needs of women treated with pelvic exenteration.