New research from Queen Mary University of London reveals women over the age of 50 who don't attend cervical screening are four times more likely to be diagnosed with cervical cancer in later life.
The study, published today PLoS Medicine and funded by Cancer Research UK, underlines the importance of screening women over 50 for cervical cancer to prevent the disease, and provides the evidence that women with normal screening results between 50- 64 have a lower risk of cervical cancer into their eighties.
Researchers examined data taken from 1,341 women who were screened aged 50 to 64 and the number of cervical cancers diagnosed between 65 to 83. They included nearly all 65 to 83-year old women in England and Wales diagnosed with cervical cancer between 2007 and 2012.
Women who had not been screened after 50 had a six fold higher risk of being diagnosed with cervical cancer than those who had been screened but had a normal result during this time— with 49 cancers being diagnosed per 10,000 unscreened women over 20 years, compared to eight cancers per 10,000 women with normal screening results.
Women who had been screened regularly but had a positive (abnormal) screening result between 50 and 64 had a risk of 86 per 10,000 women over 20 years.
The results suggest that cervical screening in women aged 50-64 has a substantial impact on cervical cancer rates not only at this age, but for many years after. The level of protection provided by having normal screening results declines over time, but even into their eighties women had a lower risk of cervical cancer compared to those who were not screened.
Peter Sasieni, Professor of Biostatistics & Cancer Epidemiology at Queen Mary University of London, Barts and The London School of Medicine and Dentistry, comments:
"Screening up to the age of 65 greatly reduces the risk of cervical cancer in the following decade, but the protection weakens with time and is substantially weaker 15 years after the last screen. With life expectancy increasing, it's important for countries that stop screening under age 60 to look into their screening programmes to maximise the number of cervical cancer cases prevented and the number of cervical cancers caught at an early stage."
The researched showed screening was equally effective for those women who were screened every five years compared to those screened every three years.
In England and Northern Ireland, women between the ages of 25 and 64 are invited for screening. Between the ages of 25 and 49 women are screened every three years. Between 50 and 64 years women have screening every five years.
In Scotland, women between 20 and 60 years are invited for screening every three years. Scotland will also extend screening for women up to the age of 64 from 2015.
In Wales, women between 20 and 64 are screened every three years.
Jessica Kirby, Cancer Research UK's senior health information manager, comments:
"These results provide reassurance that there is a real benefit to women over 50 having cervical cancer screening. Screening can pick up abnormal cells in the cervix that could develop into cervical cancer if left alone – removing these cells prevents cancer from developing. Screening is a great way of reducing the risk of cervical cancer, and saves up to 5,000 lives a year in the UK. We encourage women to take up cervical screening when invited."
More information: Castanon A, Landy R, Cuzick J, Sasieni P. (2014) Cervical Screening at Age 50 Years and the Risk of Cervical Cancer at Age 65 Years and Older: Population-Based Case Control Study. PLoS Med 11(1): e1001585. DOI: 10.1371/journal.pmed.1001585