Cervical cancer consultation Q&A
Questions and Answers on the consultation to raise the age for cervical screening in Scotland and Wales to 25
The UK National Screening Committee has recently recommended that screening should begin at 25 in Scotland and Wales – in line with existing practice in England and Northern Ireland. The current situation in Wales and Scotland, as was the case in England until 2003, is that screening starts at 20.
More information on cervical cancer screening can be found on the NHS Cervical Screening Programme website.
These Questions and Answers explain why the evidence shows screening for this condition is best started at 25.
- Screening women under the age of 25 causes more harm than good.
- Screening is not a test for cancer, but for abnormal cells which if left untreated can develop into cancer. However, these cells are very common in younger women and in the vast majority of cases will clear up of their own accord.
- If the results of a cervical screening test show abnormalities, the follow-up investigations can increase the risk of women subsequently suffering premature labour.
- What would make the biggest difference to survival for young women with cervical cancer is for symptoms to be fully recognised and treated. Work is ongoing to ensure that GPs are aware of the symptoms and the need to refer for further investigation.
- It is now known that almost all cervical cancer is caused by HPV and since 2008 a vaccination programme has been underway for teenagers, which will greatly reduce their risk of cervical cancer when they are older.
1. So does this mean nothing is being actively done for young women?
No. We now recognise that cervical cancer is almost always caused by Human Papilloma Virus (HPV) and the NHS has prioritised the vaccination of girls before they become sexually active. This programme has been running since September 2008. We vaccinate girls aged 12 to 13 years old, immunizing them against the most high risk strains before they have become sexually active. Additionally, in 2009 we carried out a ‘catch-up’ programme aimed at ensuring girls born in 1990 and onwards had been vaccinated.
2. Surely it does no harm to screen anyway to reassure women?
The screening test is not a test for cancer – it highlights abnormalities that if left might develop into cancer. An abnormal cervical screening test leads to further investigation, and it is these further investigations which can increase the risk of premature delivery.
As changes are very common in the young cervix, women screened twice (at 20 and 23) before the age of 25 have a 1 in 3 risk of having an abnormal test result (on at least one occasion) and a 1 in 20 chance of being treated. Research shows that this can lead to significant anxiety for this substantial group of women.
In the vast majority of women under 25, the abnormal cells will clear up of their own accord and follow-up investigation involves removing or destroying part of the cervix, which can increase the risk of premature births if that woman goes on to become pregnant.
It is estimated that the numbers of premature deliveries go up with approximately 1 extra premature delivery for every 275 women screened. Prematurity increases the risk of infant disability.
As cervical cancer is rare in under-25s and screening is unlikely to affect mortality (mortality in the under 25s has not increased since the age was raised in England in 2003), the additional risks it brings outweighs its potential benefits.
3. If screening of under-25s could pick up just one case early, wouldn’t this be worth it?
What would make the biggest difference to survival for those younger women who develop cervical cancer is for their symptoms to be promptly recognised and treated.
If a young woman has symptoms of pain or bleeding between periods then a screening test would actually be an unnecessary delay in getting specialist treatment. The screening test isn’t a cancer test, it just indicates whether further investigations are needed. If a woman has symptoms, we know she requires further investigation – waiting for a screening result would be unnecessary and would simply delay this. There is guidance for GPs on identifying and sending suspected cases directly to specialist care.
4. Shouldn’t young women be able to make their own choices on the risks?
Changes are very common in the young cervix, and approximately 1 in 3 women under 25 would be identified by a screening test as requiring further investigation. In the vast majority of these younger women, the abnormalities will clear up on their own so this is not a good indication of progression to cervical cancer. But if screened, this would result in follow-up gynaecological investigation, the treatment for which increases the likelihood of the woman having a pre-term delivery (premature birth).
5. If a woman under 25 has symptoms and wants to have a cervical screening test, shouldn’t she be able to have one?
If a woman is displaying symptoms, she should not be screened but given appropriate clinical management. Symptoms include unusual bleeding when she is not having her period, vaginal discharge that smells unpleasant and/or discomfort or pain during sex.
A test done because a woman has symptoms is not a screening test. We do not recommend screening women under 25 without symptoms because, as above, all the evidence shows there is no benefit to it, while there is the potential for considerable harm.
6. How many lives would be saved if screening started at 20 rather than 25?
None – since the screening age was changed in England in 2003 there has been no increase in cervical cancer mortality in women aged 20 to 25 years old or 25 to 30 years old. However, ensuring women aged 25 to 64 years old are taking up their invitation can mean a sharp drop in incidence of and mortality from cervical cancer at older ages.
7. Lots of other countries start their programmes at 20 – why does the UK not follow suit?
Some countries start at 20, others don’t start until 30. The International Agency for Research on Cancer concludes “There is minimal benefit and substantial harm in screening below age 25. Organized programmes should not include women aged less than 25 years in their target populations.” There has been a general trend for countries to increase the age of the start of their programmes. For instance, the American Cancer Society used to recommend cervical screening from age 18, but now recommends that “women under age 21 should not be tested.”
UK health screening is considered a world leader. One reason for this is because it regularly reviews all of its programmes against the available international evidence and technology to ensure they remain accurate and up to date.
These decisions are then rolled out on a national basis and fully monitored for effectiveness. Other countries have different health systems and approaches to reviewing their programmes. The UK NSC is confident that its recommendation reflects the best clinical evidence that currently exists against the technology available. Every decision is checked from scratch every three years and if the evidence is changed then so does the screening programme.
8. What about women who have started intercourse early and have had multiple partners?
In the vast majority of cases, screening these women will do them more harm than good. HPV, the virus that causes cervical cancer, is a common sexually transmitted virus and most women will be infected with it at some point in their lives without even knowing, and it will clear up without any need for medical intervention. In cases of cervical cancer, the infection has generally persisted for 10 to 50 years from the point of initial infection. If a woman is symptomatic then she should be being referred to a gynaecologist, not for a screening test which will further delay investigations.
9. Does this decision save the NHS money?
The decision not to screen women under the age of 25 is not based on cost, but on clinical evidence that it would cause more harm than good.