One study shows that additional cancer tests can be performed every year for women with very dense breasts, saving hundreds of lives each year.

Millions of women are breast screened, but routine mammograms are less effective in finding cancer in 10% of breasts with very dense breasts because tissues can hide tumors on X-rays. This is because the very dense breasts look whiter in the scan, so it is difficult to detect early disease, which also seems to be white.

Researchers at the University of Cambridge say providing this group of women with enhanced scans could find 3,500 cancer cases and save 700 lives a year in the UK. Their discovery was published in the Lancet.

"Early receiving cancer diagnosis has a huge impact on the treatment and prospects of patients. We need to change our national screening program so we can ensure that more cancers are diagnosed early, thus making more women survive better."

She added: “In addition to its relevance to the UK’s breast cancer screening program, this study has global implications for all countries that screen for breast-intensive tissues.”

The study involved 9,361 women with thick breasts in the UK and obtained negative (cancer-free) mammograms. When testing other scanning methods, an additional 85 cancers were found.

Two methods of examination were contrast-enhanced mammogram (CEM), where dyes were used to make blood vessels more pronounced and the abbreviated magnetic resonance imaging (AB-MRI) was faster than conventional MRI.

The researchers say adding any method to existing screening can detect 3,500 cancers in the UK. The University of Cambridge team said that with screening for about 20% of cancers lowering mortality rates, this could mean saving 700 lives each year.

The third scanning method used in the trial - automatic breast ultrasound (ABUS) - also absorbed cancer, but was far less effective than CEM and AB-MRI.

CEM detected 19 cancers per 1,000 scanned women, 17 cancers were found in AB-MRI, and 4 Abus found. The researchers say that since mammograms have detected about eight cancers per 1,000 breast-intensive women, the additional scans may be more than just a test for treble breast cancer.

The trial was funded by the Cancer Institute of the United Kingdom (CRUK) and supported by the National Institute of Health and Nursing Cambridge Biomedical Research Centre.

Although trials have shown that scans can detect other small cancers that may save lives, further studies are needed to confirm whether they can reduce deaths to determine the risk of overdiagnosis and estimate the cost-effectiveness ratio of providing additional scans.

"More research is needed to fully understand the effectiveness of these technologies, but these results are encouraging," said David Crosby, CRUK's head of prevention and early detection.

Now, Dr Kotryna Temcinaite, head of research communications and participation in breast cancer, said: “The UK National Screening Board now needs to view this study as part of the current review to determine whether additional imaging should be provided for women with very dense breasts during routine screening.”

She added: "Routine breast screening is the most likely pathway to successfully detect breast cancer. Although we know that the current process may be reduced in finding cancer in dense breasts, we still encourage all women to take mammograms when invited."

The Department of Health and Social Care said that enhanced scans are being conducted on women with dense breasts as part of the NHS breast screening program. A spokesman said: "The UK National Screening Commission is reviewing this evidence."