When cervical cancer is detected and treated early, the chances of successful treatment are better. Screening tests help find cervical cancer before any symptoms develop. Screening means checking or testing for disease in a group of people who don’t show any symptoms of the disease.
Currently, the most reliable method of finding cervical cancer early is the Pap test. A Pap test is a procedure that removes a small sample of cells from the cervix so they can be examined for changes. A Pap test is the main tool used to screen for cervical cancer because it can detect changes early, before cancer develops.
The human papillomavirus (HPV) test may also be used in combination with the Pap test to screen for cervical cancer. It may also be used after an abnormal Pap test result. An HPV test looks for HPV DNA in cells taken from the cervix. The test can detect high-risk types of HPV, which can cause precancerous changes in the cervix. The HPV test may be performed on the same sample of cells used for the Pap test or on a sample collected separately.
Women should talk to their doctor to learn more about their personal risk of cervical cancer and to take advantage of screening tests.
Currently, screening for cervical cancer is recommended in Canada for sexually active women between the ages of 21 and 69. Some provinces may offer screening at earlier or later ages.
Pap test
- Women who are sexually active should have regular Pap tests by the time they are 21 years of age.
- Women who are 69 or older should talk to their doctor about whether they can stop having Pap tests. The decision to stop is often based on a woman having 2 or 3 previous normal (negative) Pap results.
- Women who have never been sexually active should talk to their doctor about whether a Pap test is necessary. Some women may have been exposed to substances that put them at higher than average risk of developing cervical cancer.
- A Pap test is done every 1–3 years, depending on the provincial or territorial screening guidelines and a woman’s previous test results.
- Women with abnormal Pap test results may need to be tested more often and should follow their doctor’s advice.
- Women who stop having sex should continue to have regular Pap tests. Any woman who has ever had sex can get cervical cancer.
- Women who have had a total hysterectomy may still need a Pap test. They should talk to their doctor about whether this is necessary.
- Pap tests are usually continued if the hysterectomy was done to treat a cancerous or precancerous condition of the cervix.
- Pap tests are not necessary if the hysterectomy was done for a non-cancerous (benign) condition and the woman does not have a history of a precancerous cervical condition or HPV.
- Women who have had a partial hysterectomy should continue to have regular Pap tests based on their provincial or territorial screening guidelines.
- Women who have sex with women should follow the same Pap test recommendations as women who have sex with men.
- When a woman has a Pap test, a pelvic examination may also be done to make sure the pelvic organs are normal and to check for infections.
HPV test
- The HPV test may be used in combination with a Pap test to screen for cervical cancer.
- It may be used as a follow-up test after an abnormal Pap test result.
- It can determine if a woman has a high-risk form of HPV that can lead to cervical cancer if left untreated.
- The HPV test is used only for women 30 years of age and older.
- The HPV test is not appropriate for women younger than 30 because temporary HPV infections are very common in this age group.
- These infections are unlikely to result in abnormal cervical changes that could lead to cancer.
- Women with signs and symptoms of HPV infection, such as genital warts, may be eligible to have the test.
- When a woman has an HPV test, a pelvic examination may also be done to make sure the pelvic organs are normal and to check for infections.
More about Pap and HPV tests
- Regular Pap tests can find abnormalities and changes in the cervix before cancer develops. Most abnormal Pap test results are precancerous changes, which can be easily detected and treated successfully. Since 1977, when the Pap test was introduced as a screening test, the mortality rate from cervical cancer has dropped by about 60% and the incidence has dropped by about 50%.
- The HPV test checks for the presence of high-risk HPV types, which the Pap test cannot do. It helps identify women who presently have precancerous changes of the cervix or who are most likely to have precancerous changes and are at risk of developing cervical cancer.
- The HPV test is available in Canada, but not in all provinces or territories. It is not part of regular cervical cancer screening. Researchers are investigating how it can best be included in screening programs. Where it is available, the HPV test is not used as a replacement for the Pap test.
High-risk individuals
Women who are at higher than average risk of developing cervical cancer may need to be tested more often than women with average risk or be tested more often than recommended by their provincial or territorial guidelines. Examples of what puts a woman at higher than average risk include:
- a weakened immune system due to:
- taking drugs to suppress the immune system after an organ transplant
- human immunodeficiency virus (HIV) infection
- systemic lupus erythematosus (SLE)
- chronic use of corticosteroids
- exposure to diethylstilbestrol (DES) before birth
- persistent HPV infection with high-risk types of HPV
- long-standing or difficult to treat genital warts
- HPV-related cancers, such as cancer of the anus or vulva
Women who are at higher than average risk should talk to their doctor about a personal plan for testing. A personal plan of testing may include:
- more frequent Pap tests
- HPV test
Follow-up
If a test shows a change or abnormality, follow-up tests or procedures may be done. They include:
Screening programs
Most provinces and territories have organized cervical screening programs, each with specific guidelines. Although the guidelines may differ, all programs include regular Pap tests to improve the early detection of cervical cancer.
How to become part of a cervical cancer screening program
Cervical cancer screening is available to Canadian women through their family doctor, a cervical screening program, women’s health clinics or public health units. Women should check with their doctor or provincial or territorial screening program for details about cervical screening and what is appropriate for their particular situation.
How to locate a cervical cancer screening program
- Talk to a doctor or visit a health clinic.
- Call a provincial or territorial health telephone line, if one is available.
- Look in the phone book for the cervical cancer screening program telephone number.
- Contact the Canadian Cancer Society’s Cancer Information Service toll-free at 1 888 939-3333.
What happens after screening is done
- A doctor or trained healthcare professional sends the cervical cell samples to a laboratory.
- The screening program will send the results to the woman and her doctor.
- The woman’s doctor will decide if more tests, treatment or follow-up is needed. Follow-up options may vary. Some changes or abnormalities may or may not require treatment, depending on how severe they are.
- The screening program will send a reminder to the woman when the next Pap test is due.
See a list of questions to ask your doctor about screening.