Women who have fewer protective bacteria in the vagina may be at increased risk of developing ovarian cancer, according to new research.
The study, which was led by researchers at University College London (UCL), suggests that a smear test could help identify and treat the condition earlier.
'This is a novel approach and could revolutionise the way that we can intervene and change the implications of being at high risk of ovarian cancer development', said study lead author, Professor Martin Widschwendter of the Institute for Women’s Health at UCL.
Published in Lancet Oncology last week, the researchers analysed smear test samples from 580 women from across Europe, including 176 women with ovarian cancer, 109 with BRCA1 gene mutations that put them at high risk for ovarian cancer and 295 women with no known genetic risk.
Analysis of the samples showed that levels of the friendly bacteria Lactobacilli were significantly lower in women with ovarian cancer or with BRCA1 gene mutations. The investigators believe that the balance of bacteria (known as a microbiome) in the vagina could provide a protective barrier to infections, stopping harmful bacteria from reaching the fallopian tubes and ovaries.
Professor Widschwendter, said: 'We do not yet know for sure whether low levels of the beneficial bacteria lead to an increased risk of ovarian cancer, but that is what we suspect… It fits with other research.'
Ovarian cancer affects more than 7000 women in the UK each year. While the cause is unknown, factors such as age, family history of ovarian or breast cancer and obesity can increase the risk of women developing the condition. There is currently no screening test available for ovarian cancer but in the future, if these results can be verified, smear tests for lactobacillus levels could be used.
Helen Callard, from Cancer Research UK told BBC News: 'The microbiome is a really interesting area of research and we're slowly putting pieces together about how our natural bacteria might affect our health. But when interpreting research like this, association doesn't mean causation.'
The research was funded by grants from the EU and the Eve Appeal charity.