How Does Cancer Develop?
Genetic changes that cause cancer can happen because:
of errors that occur as cells divide.
of damage to DNA caused by harmful substances in the environment, such as the chemicals in tobacco smoke and ultraviolet rays from the sun. (Our Cancer Causes and Prevention section has more information.)
they were inherited from our parents.
The body normally eliminates cells with damaged DNA before they turn cancerous. But the body’s ability to do so goes down as we age. This is part of the reason why there is a higher risk of cancer later in life.
Each person’s cancer has a unique combination of genetic changes. As the cancer continues to grow, additional changes will occur. Even within the same tumor, different cells may have different genetic changes.
CAUSES
AWorldwide, cervical cancer is the third most common type of cancer in women. It is much less common in the United States because of the widespread use of Pap tests. Cervical cancer starts in the cells on the surface of the cervix. There are two types of cells on the surface of the cervix, squamous and columnar (gland cells). Most cervical cancers are from squamous cells.
Cervical cancer usually develops slowly. It starts as a precancerous condition called dysplasia. This condition can be detected by a Pap test and is nearly 100% treatable. It can take years for dysplasia to develop into cervical cancer. Most women who are diagnosed with cervical cancer today have not had regular Pap tests, or they have not followed up on abnormal Pap test results. Almost all cervical cancers are caused by human papillomavirus (HPV). HPV is a common virus that is spread through skin-to-skin contact and also by sexual intercourse. There are many different types (strains) of HPV. Some strains lead to cervical as well as other cancers. Other strains can cause genital warts. Others do not cause any problems at all.
A woman's sexual habits and patterns can increase her risk for developing cervical cancer. Risky sexual practices include:
Having sex at an early age
Having multiple sexual partners
Having a partner or many partners who take part in high-risk sexual activities
Other risk factors for cervical cancer include:
Not getting the HPV vaccine
Being economically disadvantaged
Having a mother who took the drug diethylstilbestrol (DES) during pregnancy in the early 1960s to prevent miscarriage
Having a weakened immune system
SYMPTOMS
Most of the time, early cervical cancer has no symptoms. Symptoms that may occur include:
Abnormal vaginal bleeding between periods, after intercourse, or after menopause
Vaginal discharge that does not stop, and may be pale, watery, pink, brown, bloody, or foul-smelling
Periods that become heavier and last longer than usual
Cervical cancer may spread to the vagina, lymph nodes, bladder, intestines, lungs, bones, and liver. Often, there are no problems or symptoms until the cancer is advanced and has spread. Symptoms of advanced cervical cancer may include:
Back pain
Bone pain or fractures
Fatigue
Leaking of urine or feces from the vagina
Leg pain
Loss of appetite
Pelvic pain
Single swollen leg
Weight loss
PREVENTION
Cervical cancer can be prevented by doing the following:
Get the HPV vaccine. The vaccine prevents most types of HPV infection that cause cervical cancer. Your provider can tell you if the vaccine is right for you.
Practice safer sex. Using condoms during sex reduces the risk for HPV and other sexually transmitted infections (STIs).
Limit the number of sexual partners you have. Avoid partners who are active in high-risk sexual behaviours.
Get Pap tests as often as your provider recommends. Pap tests can help detect early changes, which can be treated before they turn into cervical cancer.
Get the HPV test if recommended by your provider. It can be used along with the Pap test to screen for cervical cancer in women 30 years and older.
If you smoke, quit. Smoking increases your chance of getting cervical cancer.