Get to Know about Human Papilloma Virus (HPV) How does It Relate to Cervical Cancer?

What is Human Papilloma Virus (HPV)?

HPV is a very common virus and there are more than 100 types identified. The infection is usually self containing, as our body immune system can usually clear the HPV in one to two years time after infection. Different types of HPV can cause different diseases and we categorize HPV  as high risk and low risk types, according to their relation with cervical cancer.

How does one get infected with HPV?

Some types of the HPV are transmitted through intimate sexual contact. It was shown in overseas studies that up to 70% of all sexually active women have been infected by HPV sometimes in their lives. Therefore, being infected by HPV alone is not considered as suffering from a sexually transmitted disease. In case you are found to be infected, it would be difficult to trace the time and from whom you have contracted the infection. For couples who have sexual activities, both partners would have already been infected.

What diseases will be caused by low risk HPV?

Some 20 types of HPV are categorized as low risk HPV as they will not lead to cervical cancer. These HPV types can cause warts in different parts of the body, such as hands and sexual organs like the cervix, vagina or vulva. These warts may be so small that they can only be found under a magnifying glass, or they may resemble cauliflower and are big enough to be seen by visual inspection. These are not predecessors of cancer and will usually disappear gradually in a couple of years.

However, most doctors will recommend excision of big warts to improve appearance and soothe the symptoms.

How is high risk HPV related to cervical cancer?

High risk types of HPV are now known to be the cause of most cases of cervical cancer. They invade the cells in the cervix, resulting in abnormal cell changes (photo in front cover) and may lead to cervical cancer. Fortunately,  this  rarely  occurs  and  most  of  the  infected  woman  will  not develop cervical cancer. Moreover, even if it occurs, it is a very slow process and in the worst type of cellular changes, it may still take 5 to 10 years before further deterioration to cancer.

Since HPV infection is so common, I may have been infected. What type of treatment is recommended?

People get infected will not develop symptoms like fever or malaise. Specific treatment is not necessary because the infection is usually cleared by our immune system. Medical or surgical treatment is not necessary unless there is visible wart.

Test to detect High Risk HPV can help the doctor to apprehend the disease condition more accurately and unnecessary follow up investigations like repeat cervical test and colposcopic examination can then be avoided.

What is ASC-US?

ASC-US stands for Atypical Squamous Cells of Undetermined Significance. This means that there are only very  minor  changes  in  the  cervical cells under microscopic examination and there is no  pre-cancerous cells. Generally speaking, repeat cervical smear is necessary.

What to do if my cervical smear test shows ASC-US and high risk HPV infection?

You don't need to worry much because your health will definitely not be endangered in the coming months by the mildly deteriorated cells and the virus. We will refer you for a colposcopic examination performed by a specialist.

What is colposcopic examination?

You may conceptualise the colposcope as a sophisticated magnifying glass for examination  of  the  cervix  (photo  in right side). A speculum will be inserted by a doctor, just like taking a smear. Different solutions will be applied on the cervix  to  highlight  abnormal  regions. The abnormal part will be removed for laboratory  test.  The  whole  procedure takes around 10 to 20 minutes.  Further management  will  be  directed  by  the examination finding and the test result.

What should I do if my cervical smear test shows ASC-US without high risk HPV infection?

Although deteriorating cells are detected, your health will not be endangered and your chance of developing cervical cancer is low. Generally speaking, you will have repeated cervical cell test 3 years later.

Having regular cervical screening test can help to detect abnormal cell changes in an early phase for proper treatment and thereby prevent cervical cancer.

Apart from having regular cervical smear test, what else can I do to avoid getting cervical cancer?

Don't smoke! Smoking is associated with progression of cellular abnormality and cancers in the cervix. Moreover, you can reduce the risk of infection by having sex only with one partner who has sex only with you. Condoms used correctly may reduce the possibility of contracting viral infection in new sexual contacts.

Cervical smear service is available at:

  • Maternal & Child Health Centres of the Department of Health
    Cervical Screening Service 24-hour Phone Booking and Information Hotline: 3166-6631
  • Lady Helen Woo Women's Diagnostic & Treatment Centre
    Tel: 2589-2405
    Address: 2/F East Wing, Tsan Yuk Hospital, 30 Hospital Road, Sai Ying Pun, Hong Kong
  • Other Service Providers: www.cervicalscreening.gov.hk

Photos of cervical cell changes and Human Papilloma Virus under electronic microscope are provided by courtesy of Dr. Annie Cheung, Pathology Department, University of Hong Kong.

Jointly prepared by the Family Health Service of the Department of Health and the Obstetric & Gynaecology Department of the University of Hong Kong

(Content revised 03/2017)