1 Cervical cancer is the second most common cancer worldwide among women over the age of 15. Breast cancer tops the list. In Singapore, it is the fifth most common cause of cancer deaths among women. About 200 women here are diagnosed with cervical cancer each year. The cancer begins in the cervix - the part of the uterus or womb that opens to the vagina - and can spread to other parts of the body if left untreated. It is not life-threatening if caught early.

2 Cervical cancer usually hits those in their 30s to 50s although there is no age limit to being diagnosed with it.

3 Cervical cancer is caused by the human papilloma virus, or HPV, which is easily transmitted through sexual intercourse or oral sex. Using condoms can cut the risk of transmission.

About 50 to 80 per cent of women will acquire a genital HPV infection in their lifetime. In most women, the virus clears up by itself. But in a small number of women, the virus survives for years. It can then convert some cells on the surface of the cervix into cancer cells. These changes happen very slowly.

4 There are over 100 types of HPV but only 15 types are known to cause cancer. HPV types 16 and 18 cause more than 70 per cent of all cervical cancers and are known as 'high-risk' types. 'Low-risk' HPV virus types don't cause cancer but can lead to genital warts.

When infected with HPV, the cells of the cervix only show signs of a viral infection at first. But over years, the virus can cause the cells to turn pre-cancerous. Doctors call this 'cervical intraepithelial neoplasia'. In time, it can turn into invasive cervical cancer. Women who smoke increase their chances of developing cervical cancer.

5 Men can also get HPV infections which turn into cancers of the penis and rectum, but these are far rarer than cancer of the cervix. The best way to prevent HPV is to have fewer sexual partners and to always use condoms.

6 There are usually no symptoms during the early stages of cervical cancer. In its later stages, symptoms could include bleeding in between periods or during and after sexual intercourse, pelvic pain and heavy or foul vaginal discharge.

7 A pap smear is the best way to detect early stages of cervical cancer. The doctor scrapes off some cells from the surface of the cervix and tests them for abnormalities under a microscope. If your cells are abnormal, the doctors may suggest further tests to examine whether it is just an HPV infection or if it is pre-cancerous. Cells go through a series of changes before they turn into cancer. A pap smear can reveal these changes. This is why it is important to get regular pap smears.

8 Depending on the pre-cancerous changes to the cervix, treatment involves a simple surgery to remove the cancerous tissue or a wait-and-watch approach. If the cancer has spread, it may entail more radical surgery such as removal of the womb, with radiation and chemotherapy to destroy cancer cells.

9 In the case of very early, precancerous changes to the cervix, doctors may also recommend HPV DNA testing to determine if the HPV is a 'high-risk' or 'low-risk' type. If it is 'low-risk', no surgery may be necessary and they would recommend waiting for the virus to clear up on its own. If 'high-risk', they may recommend surgery in the form of a LEEP biopsy or laser vaporisation of pre-cancerous tissue.

10 Two vaccines, Cervarix and Gardasil, provide younger females with a strong immune response against HPV types 16 and 18. The vaccine is most effective when given during adolescence, before the girls start having sex. However, those already infected with HPV may not benefit. Studies are being done on vaccine efficacy in women over 25 years of age.

This story was first published in the Mind Your Body supplement on Feb 27, 2008.