Cervical Cancer

Cervical cancer is the growth of abnormal cells in the lining of the cervix.²

The cervix is part of the female reproductive system, which also includes the fallopian tubes, uterus (womb), ovaries, vagina (birth canal) and vulva (external genitals). ¹

The cervix has an outer surface that opens into the vagina and an inner surface that lines the cervical canal. These two surfaces are covered by two types of cells:

• Squamous cells – flat, thin cells that cover the outer surface of the cervix (ectocervix). Cancer of the squamous cells is called squamous cell carcinoma.
• Glandular cells – column-shaped cells that cover the inner surface of the cervix (cervical canal or endocervix). Cancer of the glandular cells is called adenocarcinoma.

The most common cervical cancer is squamous cell carcinoma, accounting for 80-85% of cases. Adenocarcinoma is less common and more difficult to diagnose because it starts higher in the cervix.²

There is no known genetic cause of cervical cancer. ¹

Nearly all cervical cancers are caused by HPV infections. Although you cannot inherit cervical cancer, you may still be more likely to have it because of your genes. For example, women with a mother or sister who had the disease may have a higher risk of developing it themselves. It is currently not understood if this is caused by an inherited condition that makes some women more vulnerable to HPV infection than others. ³

Cervical cancer is typically staged using the FIGO (International Federation of Gynaecology and Obstetrics) system.¹²

There are four stages of cervical cancer ranging from Stage I to Stage IV, which gives an indication of how little (Stage I) to how much (Stage IV) the cancer has progressed.

Within each stage (I-IV) there are sub-stages, listed from A through to D which describe the extent of the tumour.

A risk factor is any factor that is associated with an increased chance of developing a health condition, such as cervical cancer.

Cervical cancer is not infectious. It is not caused by an inherited faulty gene, so other members of your family are not likely to be at risk of developing it.³

Risk factors for cervical cancer include:^1,2,9

• Smoking and passive smoking – Chemicals in tobacco can damage the cells of the cervix, making cancer more likely to develop in women with HPV.
• Long-term use of oral contraceptive (the pill) – Research has shown that women who have taken the pill for five years or more are at increased risk of developing cervical cancer. The reason for this is not clear. However, the risk is small and the pill can also help protect against other types of cancer, such as uterine and ovarian cancers.
• Having a weakened immune system – The immune system helps rid the body of HPV. Women with a weakened immune system have an increased risk of developing cervical cancer and need to have more frequent cervical screening tests. This includes women with the human immunodeficiency virus (HIV) and women who take medicines that lower their immunity.
• HPV infection – HPV is a common sexually transmitted infection which can be responsible for the development of many cancers and other conditions. Almost all cases of cervical cancer are caused by persistent infection with some high-risk types of the human papillomavirus (HPV); this is the biggest risk factor for cervical cancer. Around eight out of 10 women will become infected with genital HPV at some time in their lives. Most women who have the HPV infection never get cervical cancer; only a few types of the HPV result in cervical cancer.
• Age – It is very rare for women under the age of 25 to develop cervical cancer, with the risk increasing as you age.
• Sexual history – Several factors can increase your risk of cervical cancer, including becoming sexually active at a young age, having many sexual partners and having a partner who is considered high risk. This is primarily because of the increased risk of HPV infection.

Cervical cancer is most commonly caused by persistent infection with the human papillomavirus (HPV), with high-risk types of HPV responsible for around 70% of cervical cancers.⁸

The most important ways to prevent cervical cancer are:

• HPV vaccination – HPV vaccines protect against high-risk types of HPV which commonly cause cervical cancer. They are most effective when given before first sexual exposure and are recommended for women aged between nine and 26 years of age, or as advised by your doctor if above this age.⁷
• Screening – Cervical cancer screening is recommended for women aged 25 years and above. Depending on your age you may receive a Pap test or a HPV test, which test for changes in the cervix and the presence of high-risk types of HPV. It is important to ensure you receive cervical cancer screening at the recommended frequency (every three years for Pap tests and five years for HPV tests).⁶