Cervical, vaginal and vulvar cancer: Why screening and vaccination are the best preventive options

If there's one thing Dr See Hui Ti advises when it comes to gynaecological cancers caused by an infection of the human papillomavirus (HPV), it is to speak with your doctor about regular screening and vaccination.

The senior consultant at Medical Oncologist at Parkway Cancer Centre says that cervical, vaginal and vulvar cancers are largely preventable with regular screening and HPV vaccination.

"As long as there is no HPV exposure, no HPV infection, or there is good immunity against HPV, then the risk of getting these HPV-related cancers is low, but not nil," says Dr See.

Cervical cancer is among the top 10 most common cancers among women in Singapore, and the second leading cause of death for women aged 15 to 44 here.

The frequency of vaginal and vulvar cancers are much rarer, with approximately a 0.3 to 0.9 per cent incidence rate in females.

Many patients she sees are in their late 30s and already in the late stages of cervical, vaginal or vulvar cancer with their organs compromised. By then, according to Dr See, it is too late hence she urges early screening and vaccination."

Here are four important things you need to know about HPV-related cancers:

HPV is transmitted when exposed to the mucosal surface of the vagina, vulva, cervix, rectum, anus or mouth. This means it can also be transmitted without penetrative sex, through skin-to-skin contact such as heavy petting.

However, not all HPV strains lead to cancer.

According to the World Health Organisation, there are over 100 types of HPV strains and at least 14 of them can lead to cancer. Of these, HPV types 16 and 18 are responsible for causing 70 per cent of cervical cancers worldwide.

Currently, there is no treatment for HPV infection. Some strains of the virus cause low grade infections, which usually can go away on their own, while some cause high grade inflammation, infection and mutation. It takes 15 to 20 years for cervical cancer to develop in women with normal immune systems. It can take only five to 10 years in women with weakened immune systems, such as those with untreated human immunodeficiency virus (HIV) infection. These infections can be detected through regular screening and treated before they develop into cancer cells.

However, it is also more difficult for women above the age 30 to clear HPV infections, says Dr See.

"A woman below 30 years old can be infected with HPV and they are usually able to clear that infection. For HPV infection in a woman after the age of 30, it means that if the infection has not cleared up, it is unlikely to clear, and the chances of getting cervical cancer from this infection is higher," she says.

Besides being able to pass the HPV to women, men can also pass HPV to their male partners through oral sex. If HPV is transmitted through anal sex, it may also develop into anal cancer.

Men should speak with their doctors to find out how they can protect themselves against HPV.

Cervical, vaginal and vulvar cancers have no symptoms in their early stages. Only early screening can detect the presence of cancer-causing HPV.

If the cancer is detected in its early stage, a patient can then undergo surgery to remove the cervix. Depending on the results, a patient may need chemotherapy or radiation.

"At the end of that, we will do a scan in the following years. If the cancer does not come back after five years, it is unlikely to come back. But we do advise them to return for follow-up in case other organs like the vagina and vulva are affected," says Dr See.

She shares that sometimes she receives patients who have gone for screening but not regularly, which may lead to a HPV infection going undetected and causing cancer.

Others may have gone for a Pap smear but did not take the HPV test and the infection was not detected.

The procedure for a Pap smear and HPV test is the same - it involves gently scraping the cells of the cervix. Pap smear samples are then examined under a microscope for any abnormal cells while the HPV tests for the DNA of cancer-causing HPV strains.

Apart from regular screening, Dr See encourages vaccination. In Singapore, vaccination can start from as early as age nine as it is generally recommended for people who are not yet sexually active.

"The younger we do the vaccination, the greater our response and the longer our bodies remember such a vaccination. Therefore ideally, the HPV vaccine should be given in early adolescence because vaccination is most effective before exposure to HPV through sexual activity." says Dr See.

By the time one experiences symptoms of cervical cancer, which include vaginal bleeding and pelvic pain, the cancer has already progressed to at least stage 2, where the cancer has grown beyond the cervix. This means that the treatment may not be as simple as removal by surgery.

Similarly, vaginal cancer symptoms include bleeding or discharge, pain during sexual intercourse, in the pelvic area or when urinating.

"The earlier stage the cancer is in, the simpler the treatment; the later stage the cancer is in, the more complex. When it reaches stage 4, there is a low chance of cure and the patients have to be on chemotherapy for the rest of their lives" she says.

Her advice: "For those who have been vaccinated, get screening done - HPV testing if you can. If you can't get access to the HPV test, continue with Pap smears every year until it's normal for three years. Then do it once every three years until you are not sexually active anymore."

Screening
Cervical cancer screening is available for women of all ages and is offered at all polyclinics and any participating private clinics.

Women aged 25 to 29 who have had sexual intercourse are encouraged to go for a Pap smear once every three years. For women aged 30 and above, they can go for a HPV test once every five years.

Vaccination
HPV vaccination can be taken at all polyclinics and is widely available at many private clinics. Parents of Secondary 1 and 2 children can opt for their daughters to be vaccinated under the National School-based HPV Programme. The programme is only available for females.