CERVICAL SCREENING

What is Cervical screening?

Cervical screening is the process of identifying women who appear healthy but may be at increased risk of cervical cancer. Evidence suggests many more lives would have been lost to cervical cancer if not for screening.

Who should undergo Cervical screening?

The Department of Health in the UK recommends cervical screening for women between the ages of 25 and 64 years but screening can be performed at any time if there are overriding clinical considerations. Women aged 25 to 49 years should be screened every 3 years while women aged 50 to 64 years should be screened every 5 years. Evidence suggests that the chance of developing cervical cancer if a woman has never had sex is low; there is therefore no justification in screening a woman that has never had sexual intercourse. HPV vaccination programme (see below) started in 2008; current advice is that vaccinated women should continue routine cervical screening.

How is Cervical screening performed?

Cervical screening involves taking and examining a sample of cells from the surface of the cervix (neck of the womb) looking for abnormalities. The test is done by passing a speculum to expose the cervix and using a special brush to obtain the cell sample. The test can only be performed when the woman is not on a period to obtain best quality results.

What tests are done during Cervical screening?

Cervical screening uses liquid based cytology (LBC) to collect samples of cells from the cervix and these are examined under a microscope to look for any abnormal changes in the cells. Cervical screening now also incorporates Human papillomavirus (HPV) testing. HPV is a common virus transmitted through sexual contact and there are over 100 subtypes most of which do not cause significant disease and are easily eradicated by the immune system without need for treatment. Some subtypes of HPV (known as high risk HPV [HR-HPV]) can lead to abnormal cervical cells and if left untreated, these abnormal cells may go on to develop into cervical cancer, in particular HPV16 and HPV18. Early detection and treatment of these HPV subtypes can prevent 75% of cervical cancers developing.

What can women expect from Cervical screening?

Negative cervical screening results are reassuring and mean the women can be rescreened after 3 or 5 years depending on age. Screening results showing borderline or low grade abnormal cell changes (dyskaryosis) are interpreted based on HR-HPV test result. Women positive for HR-HPV require further diagnostic testing/treatment while those negative for HR-HPV can return to routine screening.

What further test/treatment might be required?

Women found to have moderate or high grade cervical cell changes and those positive for HR-HPV will be referred for colposcopy (microscopic examination of the cervix) and any further treatment required for the abnormality.

What are the risks of Cervical screening?

Cervical screening is a relatively painless and safe procedure but the process is not perfect; there can be false positives and false negatives. The addition of HR-HPV testing has helped to reduce false positive results.