Cervical cancer is malignant neoplasm of the cervix uteri or cervical area. One of the most common symptoms is abnormal vaginal bleeding, but in some cases there may be no obvious symptoms until the cancer is in its advanced stages. Treatment consists of surgery (including local excision) in early stages and chemotherapy and radiotherapy in advanced stages of the disease.
Pap smear screening can identify potentially precancerous changes. Treatment of high grade changes can prevent the development of cancer. In developed countries, the widespread use of cervical screening programs has reduced the incidence of invasive cervical cancer by 50% or more.
Human papillomavirus (HPV) infection is a necessary factor in the development of almost all cases of cervical cancer. HPV vaccines effective against the two strains of HPV that currently cause approximately 70% of cervical cancer have been licensed in the U.S, Canada, Australia and the EU. Since the vaccines only cover some of the cancer causing ("high-risk") types of HPV, women should seek regular Pap smear screening, even after vaccination.
The cervix is the narrow portion of the uterus where it joins with the top of the vagina. Most cervical cancers are squamous cell carcinomas, arising in the squamous (flattened) epithelial cells that line the cervix. Adenocarcinoma, arising in glandular epithelial cells is the second most common type. Very rarely, cancer can arise in other types of cells in the cervix.
Early cervical cancers usually don't cause symptoms.
When the cancer grows larger, women may notice one or more of these symptoms:
- Abnormal vaginal bleeding.
- Bleeding that occurs between regular menstrual periods.
- Bleeding after sexual intercourse,douching, or a pelvic exam.
- Menstrual periods that last longer and are heavier than before.
- Bleeding after going throughmenopause.
- Increased vaginal discharge.
- Pelvic pain.
- Pain during sex.
Infections or other health problems may also cause these symptoms. Only a doctor can tell for sure. A woman with any of these symptoms should tell her doctor so that problems can be diagnosed and treated as early as possible.
Human papillomavirus (HPV) infection with high-risk types has been shown to be a necessary factor in the development of cervical cancer. HPV DNA may be detected in virtually all cases of cervical cancer. Not all of the causes of cervical cancer are known. Several other contributing factors have been implicated.
Human papillomavirus infection
In the United States each year there are more than 6.2 million new HPV infections in both men and women, according to the CDC, of which 10 percent will go on to develop persistent dysplasia or cervical cancer. That is why HPV is known as the "common cold" of the sexually transmitted infection world. It is very common and affects roughly 80 percent of all sexually active people, whether they have symptoms or not.
The most important risk factor in the development of cervical cancer is infection with a high-risk strain of human papillomavirus. The virus cancer link works by triggering alterations in the cells of the cervix, which can lead to the development of cervical intraepithelial neoplasia, which can lead to cancer.
Women who have many sexual partners (or who have sex with men who had many other partners) have a greater risk.
More than 150 types of HPV are acknowledged to exist (some sources indicate more than 200 subtypes). Of these, 15 are classified as high-risk types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68, 73, and 82), 3 as probable high-risk (26, 53, and 66), and 12 as low-risk (6, 11, 40, 42, 43, 44, 54, 61, 70, 72, 81, and CP6108). Types 16 and 18 are generally acknowledged to cause about 70% of cervical cancer cases. Together with type 31, they are the prime risk factors for cervical cancer.
Genital warts are caused by various strains of HPV which are usually not related to cervical cancer. However, it is possible to have multiple strains at the same time, including those that can cause cervical cancer along with those that cause warts.
The medically accepted paradigm, officially endorsed by the American Cancer Society and other organizations, is that a patient must have been infected with HPV to develop cervical cancer, and is hence viewed as a sexually transmitted disease (although many dispute that, technically, it is the causative agent, not the cancer, that is a sexually transmitted disease), but most women infected with high risk HPV will not develop cervical cancer.
Use of condoms reduces, but does not always prevent transmission. Likewise, HPV can be transmitted by skin-to-skin-contact with infected areas. In males, there is no commercially available test for HPV, although HPV is thought to grow preferentially in the epithelium of the glans penis, andcleaning of this area may be preventative.
The American Cancer Society provides the following list of risk factors for cervical cancer: human papillomavirus (HPV) infection, smoking, HIV infection, chlamydia infection, stress and stress-related disorders, dietary factors, hormonal contraception, multiple pregnancies, exposure to the hormonal drug diethylstilbestrol, and family history of cervical cancer. Early age at first intercourse and first pregnancy are also considered risk factors, magnified by early use of oral contraceptives. There is a possible genetic risk associated with HLA-B7.
There has not been any definitive evidence to support the claim that circumcision of the male partner reduces the risk of cervical cancer, although some researchers say there is compelling epidemiological evidence that men who have been circumcised are less likely to be infected with HPV. However, in men with low-risk sexual behaviour and monogamous female partners, circumcision makes no difference to the risk of cervical cancer.
Women with cervical cancer have many treatment options. The options are surgery,radiation therapy, chemotherapy, or a combination of methods.
The choice of treatment depends mainly on the size of the tumor and whether the cancer has spread. The treatment choice may also depend on whether you would like to become pregnant someday.
Your doctor can describe your treatment choices, the expected results of each, and the possible side effects. You and your doctor can work together to develop a treatment plan that meets your medical and personal needs.
Your doctor may refer you to a specialist, or you may ask for a referral. You may want to see a gynecologic oncologist, a surgeon who specializes in treating female cancers. Other specialists who treat cervical cancer include gynecologists, medical oncologists, and radiation oncologists. Your health care team may also include an oncology nurse and a registered dietitian.
Before treatment starts, ask your health care team about possible side effects and how treatment may change your normal activities. Because cancer treatments often damage healthy cells and tissues, side effects are common. Side effects may not be the same for each person, and they may change from one treatment session to the next.
At any stage of the disease, supportive care is available to relieve the side effects of treatment, to control pain and other symptoms, and to help you cope with the feelings that a diagnosis of cancer can bring.