January is Cervical Cancer Awareness Month
What is cervical cancer?
The cervix is the lower part of the uterus (womb). Most cervical cancers begin in the cells lining the cervix. These cells do not suddenly change into cancer. Instead, the normal cells of the cervix gradually develop pre-cancerous changes that turn into cancer. Cervical cancers and cervical pre-cancers are classified by how they look under a microscope. There are 2 main types of cervical cancer: squamous cell carcinoma and adenocarcinoma. About 80% to 90% of cervical cancers are squamous cell carcinomas. These cancers start in the squamous cells that cover the surface of the exocervix. Under the microscope, this type of cancer is made up of cells that are like squamous cells.
Most of the remaining cervical cancers are adenocarcinomas. Cervical adenocarcinomas seem to have become more common in the last 20 to 30 years. Cervical adenocarcinoma develops from the mucus-producing gland cells of the endocervix. Less commonly, cervical cancers have features of both squamous cell carcinomas and adenocarcinomas. These are called adenosquamous carcinomas or mixed carcinomas.
Although cervical cancers start from cells with pre-cancerous changes (pre-cancers), only some women with pre-cancers of the cervix will develop cancer. The change from pre-cancer to cancer usually takes several years -- but it can happen in less than a year. For most women, pre-cancerous cells will remain unchanged and go away without any treatment. Still, in some women pre-cancers turn into true (invasive) cancers.
What are the signs and symptoms of cervical cancer?
Women with early cervical cancers and pre-cancers usually have no symptoms. Symptoms often do not begin until a pre-cancer becomes a true invasive cancer and grows into nearby tissue. When this happens, the most common symptoms are:
These signs and symptoms can also be caused by conditions other than cervical cancer. For example, an infection can cause pain or bleeding. Still, if you have any of these problems, you should see your health care professional right away -- even if you have been getting regular Pap tests. If it is an infection, it will need to be treated. If it is cancer, ignoring symptoms may allow it to progress to a more advanced stage and lower your chance for effective treatment.
Even better, don't wait for symptoms to appear. Have a regular Pap test and pelvic exam.
What are the risk factors of cervical cancer?
Human papilloma virus infection: The most important risk factor for cervical cancer is infection by the human papilloma virus (HPV).
Smoking: Women who smoke are about twice as likely as non-smokers to get cervical cancer.
Immunosuppression: Human immunodeficiency virus (HIV), the virus that causes AIDS, damages the body's immune system and places women at higher risk for HPV infection.
Chlamydia Infection: Chlamydia is a relatively common kind of bacteria that can infect the reproductive system. It is spread by sexual contact.
Diet: Women with diets low in fruits and vegetables may be at increased risk for cervical cancer.
Oral Contraceptives: There is evidence that taking oral contraceptives (OCs) for a long time increases the risk of cancer of the cervix. Research suggests that the risk of cervical cancer goes up the longer a woman takes OCs, but the risk goes back down again after the OCs are stopped.
Multiple full-term pregnancies: Women who have had 3 or more full-term pregnancies have an increased risk of developing cervical cancer.
Young age for first full-term pregnancy: Women who were younger than 17 years when they had their first full-term pregnancy are almost 2 times more likely to get cervical cancer later in life than women who waited to get pregnant until they were 25 years or older.
Poverty: Poverty is also a risk factor for cervical cancer.
Diethylstilbestrol (DES): DES is a hormonal drug that was given to some women to prevent miscarriage between 1940 and 1971. Women whose mothers took DES when pregnant with them are often called DES daughters. These women develop clear cell adenocarcinoma of the vagina or cervix more often than would normally be expected.
Family history: Cervical cancer may run in some families. If a woman’s mother or sister had cervical cancer, her chances of developing the disease are 2 to 3 times higher than if no one in the family had it.
See the American Cancer Society's web page for more details on the risk factors for cervical cancer.
How is cervical cancer diagnosed?
The goal of screening for cervical cancer is to find cervix cell changes and early cervical cancers before they cause symptoms. Screening refers to the use of tests and exams to find a disease, such as cancer, in people who do not have any symptoms.Early detection means applying a strategy that results in an earlier diagnosis of cervical cancer than otherwise might have occurred. Screening tests offer the best chance to detect cervical cancer at an early stage when successful treatment is likely. Screening can also actually prevent most cervical cancers by finding abnormal cervix cell changes (pre-cancers) so that they can be treated before they have a chance to turn into a cervical cancer.
Cancer of the cervix may be prevented or detected early by regular Pap tests. If it is detected early, cervical cancer is one of the most successfully treatable cancers. In the United States, the cervical cancer death rate declined by almost 70% between 1955 and 1992, in large part due to the effectiveness of Pap smear screening. The death rate continues to decline each year.
Despite the recognized benefits of Pap test screening, not all American women take advantage of it. As of the year 2000, slightly over 80% of women had had a Pap test in the previous 3 years. Asian-American women, recent immigrants, women without health insurance, and women with fewer years of education were less likely to have had regular Pap tests.
Between 60% and 80% of American women with newly diagnosed invasive cervical cancer have not had a Pap smear in the past 5 years. Many of these women have never had a Pap test.
Cervical cancer deaths are higher in populations around the world where women do not have routine Pap tests. In fact, cervical cancer is the major cause of cancer deaths in women in many developing countries. These women are usually diagnosed with an invasive late stage, rather than as pre-cancers or early cancers.
What we're doing at the Purdue University Center for Cancer Research
Purdue receives .35 million grant to develop cervical cancer diagnostic tool.