Two Pronged Prevention Strategy: Vaccination and Testing
The introduction of the Human Papilloma virus (HPV) vaccination in 2008 for adolescent girls in secondary school was a vital step in the prevention of Cervical Cancer. HPV, a common virus that 8 in 10 people will get, is associated with 99% of cervical cancer diagnoses. More than ten million doses of HPV vaccine have been given - over 80% of women aged 15-24 have received the vaccine, protecting this generation from developing cervical cancer in the future.
However, there are millions of women who passed puberty before the vaccine was available, which is why Cervical Screening – previously known as the Smear Test – is so important. During the pandemic, however, the number of smear tests undertaken has dropped – due to a combination of lack of NHS resources and patient fear.
Using the #SmearForSmear campaign tag, Cervical Cancer Prevention Week – 18th to 24th January – is working to make sure as many people as possible know how they can reduce their risk of the disease and to educate others.
Understanding Cervical Cancer
Cervical cancer is the uncontrolled growth of abnormal cells in the lining of the cervix and eventually form a tumour. If not caught early cancer cells gradually grow into the surrounding tissues and may spread to other areas of the body. Around 3,200 women are diagnosed with cervical cancer in the UK each year – and the main cause of cervical cancer is long lasting (persistent) infection of certain types of HPV.
HPV infects the skin and any moist membrane, including the cervix, lining of the mouth and throat, the vagina, vulva and anus. Both men and women can have HPV and it is usually passed on through sexual contact. There are over 200 types of HPV and the vast majority are low risk - in most cases an individual’s immune system will get rid of the virus without it causing any problems.
However, about 13 high-risk HPV types are linked to cancer, with high-risk types 16 and 18 causing most (over 70%) of cervical cancers. Overall, nearly all cases of cervical cancer (99.7%)
are caused by high-risk HPV.
Routine HPV check
Cervical screening is an important part of the prevention strategy. The routine test – carried out every three to five years, depending on age – is not a test for cancer but to pick up abnormal cervical cells that, if left untreated, might develop into cancer. Better understanding of the HPV types has led to a refinement of the test: in England, Scotland and Wales, the Cervical Screening test now also includes a test for high-risk HPV. Northern Ireland will also switch to using this test in the future.
If a patient has high-risk HPV, the sample will then be checked for cell changes. A patient with cell changes will then be invited for a colposcopy to look closer at the cervix – if there are no cell changes the patient will be invited back for further screening in one year. If high risk HPV isn't found, the sample will not be tested for cell changes because cell changes or cervical cancer are unlikely to develop without high risk HPV.
COVID-19 affected screening
In the UK, individuals aged between 25 and 64 with a cervix are invited for cervical screening, every three years for those under 50, and then every five years. However, during 2020 the numbers of people offered a screening dropped dramatically, according to analysis of The Health Improvement Network (THIN®), a Cegedim database.
While over 246,000 patients have a record of being offered a cervical cancer screen in 2019, this dropped to just 127,000 patients in 2020. Take up remains an issue for cervical screening due to a number of factors, from embarrassment to discomfort: smear tests can be extremely painful for some women.
The impact of the pandemic reduced uptake even more. While over 190,000 patients have a record of receiving a cervical cancer screen in 2019 (77% uptake), in 2020 this dropped to just 90,000 (70% uptake), suggesting additional concerns associated with exposure to COVID-19.
Cervical Cancer Symptoms
The importance of screening cannot be underestimated as cervical cancer may not cause any symptoms – or the symptoms may not be obvious. Common symptoms can include vaginal bleeding that is unusual for an individual patient, including after the menopause, after sex, or between regular periods; changes to vaginal discharge; pain or discomfort during sex and unexplained pain in the lower back or pelvis.
Many of these symptoms will be due to reasons other than cervical cancer – however according to analysis of THIN®, 33% of active patients with a diagnosis of cervical cancer have a record of abdominal pain or abdominal swelling in THIN®. Furthermore, 9% of active patients with a diagnosis of cervical cancer have a record of experiencing postmenopausal, irregular menstrual or post-coital bleeding in THIN®.
Given the drop in Cervical Screening undertaken during the past 12 months, it has never been more important to improve awareness of Cervical Cancer and reinforce the need for regular tests. But with so much pressure on clinicians in both primary and secondary care, it is also important to prioritise where possible.
The average age of diagnosis of patients in THIN® is 51 – however the peak decade for diagnosis is 30 to 39 (28%), followed by 40 to 49 (23%). Well over half (58%) of active patients with a diagnosis of cervical cancer report being either a past or current smoker in THIN®.
THIN® data can provide vital insights – not least in helping to identify those individuals who have missed a routine test and those – such as smokers – who are most at risk. Reinforcing the potential implications of abdominal swelling and unusual bleeding will also help primary care providers encourage and prioritise testing.
THIN® is an unobtrusive medical data collection scheme that collects anonymised patient data from its members.
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