Women under 25 should be offered cervical screening

Last month, the British Medical Journal reported a fall in the number of young women attending smear tests. Now, two senior doctors warn that a new policy not to screen women aged 20-24 may be a factor in falling coverage and could increase the risk of cancer developing in young women.

Prevalence of carcinoma in situ (a precursor to cancer known as CIN3) has increased in women aged 20-24, write consultants Amanda Herbert and John Smith. This new policy will add more than 3000 women with untreated CIN3 to the larger numbers failing to accept their invitations later on, they warn.

The authors accept that CIN may regress, that invasive cervical cancer (ICC) is rare in women under 25, and that screening does little to reduce its incidence in such young women. However, they argue that ICC can develop within a couple of years of missed cell analysis, failure to investigate cell abnormalities, or incomplete treatment, emphasising the importance of treating high-grade CIN when it is found.

Screening in the UK has been highly successful and, since 1988, incidence and mortality have fallen by more than 40% despite increased risk of disease. This has been achieved by treating high-grade CIN, particularly CIN3, in young women, say the authors. The peak prevalence of CIN3 is in women aged 25-29 amongst whom the fall in coverage has been greatest.

ICC is more difficult to prevent in young women because there are less screening opportunities to treat precancerous lesions before they become invasive, they add.

They believe that decisions about treatment of CIN should be based on a balance between risk of progression, likelihood of regression and risk of treatment. Women should be informed about the risk of high-grade CIN, its greater frequency in young women, the importance of surveillance, and the fact that an epidemic of cervical cancer has been prevented by screening women when they were young.

General practitioners and clinics should not be prevented from screening women whom they believe to be at risk if those women themselves want to be screened, they conclude.