Cervical cancer is the cancer that occurs in the lower, narrow end of the uterus (womb) which connects a woman’s uterus to her vagina. Cervical cancer is the fourth most common cancer in women and is most common in women ages 35 to 55 but can affect women of all ages. 500 000 new cervical cancer cases are diagnosed annually worldwide where more than 80% are diagnosed at advanced stage and have poor treatment outcomes. Yet it is largely preventable thanks to cervical screening and human papillomavirus (HPV) vaccination.
Cervical cancer is almost always caused by a virus called human papillomavirus (HPV). There are many different types of HPV and some types of HPV can lead to cervical cancer. HPV is passed from one person to another during sex. Two tests are used to screen for cervical cancer. First Pap test, looks for abnormal changes in cells. These changes may suggest that cancer may develop in the future. Second is HPV test. This test looks for the type of HPV virus that causes cervical cancer. Risk factors for cervical cancer include smoking, inadequate sexual healthcare, multiple sexual partners, human papillomavirus infection, early onset of sexual activity.
Human papilloma virus (HPV) vaccines are used to prevent HPV infection and therefore cervical cancer. Available vaccines protect against either two, four or nine types of HPV. All vaccines protect against at least HPV 16 and 18 that are the greatest risk of cervical cancer. They may prevent 70% of cervical cancer, 80% of anal cancer, 60% of vaginal cancer and 40% of vulvar cancer. They also prevent some genital warts with the vaccines against 4 and 9 HPV types providing greater protection.
The World Health Organization (WHO) recommends HPV vaccines as part of routine vaccinations in countries that can afford them, along with other prevention measures. It is recommended for women who are 9 to 25 years old who have not been exposed to HPV. When Gardasil was first introduced, it was recommended as a prevention for cervical cancer for women that were 25 years old or younger. New evidence suggests that all HPV vaccines are effective in preventing cervical cancer for women up to 45 years of age. For maximum effect, it is recommended that girls receive the vaccine prior to becoming sexually active. However, women who were already infected with one or more of the four HPV types targeted by the vaccine (6, 11, 16, or 18) were protected from clinical disease caused by the remaining HPV types in the vaccine.
Gardasil has been shown to also be effective in preventing genital warts in males. Vaccine was approved by the FDA for use in males aged 9 to 26 for prevention of genital warts and anal cancer. While Gardasil and Gardasil-9 vaccines have been approved for males. Cervarix (the other available vaccine) is not administered to males. Unlike the Gardasil based vaccines, Cervarix does not protect against genital warts.
HPV vaccines are very safe. However pain at the site of injection, redness and swelling at the site and fever may occur.
Cervical cancer screening is still required following vaccination. Neither vaccine treats existing HPV infection or cervical cancer nor do they prevent other sexually transmitted diseases. Screening tests offer the best chance to have cervical cancer found 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.
The American Cancer Society recommends the following:
All women should begin cervical cancer testing (screening) at age 21. Women aged 21 to 29, should have a Pap test every 3 years. HPV testing should not be used for screening in this age group (it may be used as a part of follow-up for an abnormal Pap test).
Beginning at age 30, the preferred way to screen is with a Pap test combined with an HPV test every 5 years. This is called co-testing and should continue until age 65.
Another reasonable option for women 30 to 65 is to get tested every 3 years with just the Pap test.
Women over 65 years of age who have had regular screening in the previous 10 years should stop cervical cancer screening as long as they haven’t had any serious pre-cancers (like CIN2 or CIN3) found in the last 20 years. Women with a history of CIN2 or CIN3 should continue to have testing for at least 20 years after the abnormality was found.
Some women believe that they can stop cervical cancer screening once they have stopped having children. This is not true. These guidelines for early detection of cervical cancer do not apply to women who have been diagnosed with cervical cancer, cervical pre-cancer, or HIV infection. These women should have follow-up testing and cervical cancer screening as recommended by their healthcare team.
Despite the recognized benefits of cervical cancer screening, not all women take advantage of it. Cervical cancer deaths are higher in populations around the world where women do not have routine cervical cancer screening. These women are usually diagnosed with late stage cancers with high morbidity and mortality.