Cancer of the Cervix
(Cervical Cancer)
In this condition factsheet:
The Facts on Cancer of the Cervix
Cervical cancer affects the cervix, which is a part of the female reproductive system. The cervix is the lowest portion of the uterus (womb) and is located at the top of the vagina. The cervix is made up of cells which can change from being healthy to abnormal.
Cancer refers to a class of diseases in which abnormal cells grow without control. The term tumour or neoplasm refers to an abnormal growth of cells. Tumours can either be noncancerous (benign) or cancerous (malignant). A benign tumour does not spread to surrounding tissues or organs and usually does not come back after it has been removed. On the other hand, a malignant tumour can spread (e.g., from the cervix) and invade other tissues or organs in the body.
Cervical cancer is the third most common type of gynecological cancer in North America and the fourth most common cancer in women worldwide. The incidence of cervical cancer has declined dramatically since the 1950s. The Pap test screening (also known as Pap smear) was the major contributing factor to this decline. The Pap test detects cell changes in the cervix.
As discussed above, some of these changes are noncancerous, but some cells may become precancerous. If precancerous cells are left untreated, they can progress to invasive cancer of the cervix. Regular Pap test screening allows for early detection of precancerous cells and for initiation of treatment before these calls become cancerous.
In Canada it is estimated that approximately 1,550 new cases of cervical cancer are diagnosed each year. About 400 people will die from cervical cancer each year. The lifetime probability of a Canadian developing cervical cancer is estimated to be 1 in 168. Fortunately, almost all cervical cancer can be cured when diagnosed and treated at an early stage. The cure rate for stage 1 cervical cancer (cancer limited to the cervix) is 80% to 90%.
Since some types of human papillomavirus (HPV) can cause cancer of the cervix, HPV vaccination has been made available in Canada since 2006. It is recommended that females between the ages of 9 and 45 receive the HPV vaccine to protect them from strains of the HPV virus responsible for approximately 70% of cervical cancers.
Although males cannot get cervical cancer, vaccinating boys and young men against HPV is still beneficial. It helps prevent the spread of HPV and also helps reduce their risk of anal cancer and genital warts, which are also caused by HPV. Vaccination is recommended for males between the ages of 9 to 45.
For the most part, cervical cancer can be prevented and cured when detected in the early stages.
Causes of Cancer of the Cervix
So far, it is not fully understood what causes cells to become abnormal and to grow without control. Some factors have been observed to increase the risk of developing cancer of the cervix.
HPV: The most important risk factor is the infection of the cervix with HPV. HPV is one of the most common sexually transmitted infections (STIs). It is estimated that 75% of individuals who are sexually active will have at least one HPV infection in their lifetime, many of which are without symptoms. While some types of HPV cause genital warts, other strains of the virus can infect the cervix and then cause abnormal changes within the cells that may slowly progress to cancer. It is important to note that most people diagnosed with cervical cancer had a previous HPV infection; however, not all people with an HPV infection will develop this type of cancer.
Sexual activity: Becoming sexually active at an early age is linked to a higher risk of cervical cancer. Also, certain sexual behaviours (such as having multiple sex partners and partners who have multiple partners) can increase a person's likelihood of becoming infected with HPV, thereby increasing the risk of cervical cancer.
Smoking: People who smoke are at higher risk of cervical cancer, as well as other cancers. Both tobacco smoking and exposure to secondhand smoke (environmental tobacco smoke) have been associated with the development of cervical cancer. In fact, the risk increases with the length of time a person smokes and the number of cigarettes consumed per day.
Weakened immune system: Our immune system helps our body fight infections. Therefore, medications and diseases that diminish the immune system can increase a woman's risk of HPV infections, thereby increasing the risk of cervical cancer. Examples of medications that suppress the immune systems are corticosteroids (used over a long period of time) and chemotherapy drugs. People infected with the human immunodeficiency virus (HIV) have an increased risk of developing precancerous cervical changes with an HPV infection.
Age: Most cases of cervical cancer tend to occur in people younger than 50 years of age.
Socioeconomic status: People with lower incomes are at higher risk of developing cervical cancer because they are less likely to receive regular Pap test screenings.
Oral contraceptives: Using birth control pills for a long time (for example, more than 10 years) increases the risk of cervical cancer in people with an HPV infection. This risk decreases once the pill is stopped.
Multiple births: People who have given birth multiple times are at increased risk of cervical cancer, with the risk increasing as the number of births increase.
Other risk factors: Other possible factors have been associated with increased risk of cervical cancer. However, there is currently not enough evidence to consider them as main risk factors. These factors include having a family history of cervical cancer or a history of sexually transmitted infections.
Symptoms and Complications of Cancer of the Cervix
In the early stages of cervical cancer, the woman may or may not experience symptoms. It is important to note that some symptoms of cervical cancer can also be caused by other health conditions.
Possible early symptoms may include:
- abnormal vaginal bleeding or spotting between periods
- pain during sexual intercourse or bleeding after intercourse
- clear, watery, or foul-smelling discharge from the vagina
- increased amount of vaginal discharge
Late symptoms can occur as the tumours grow large or invade other organs of the body:
- pelvic or back pain
- urine leakage (incontinence) or blood in the urine (hematuria)
- weight loss
- appetite loss or anorexia
- shortness of breath
- anemia (causing lack of energy and shortness of breath)
- blood in the stool
- constipation
