A BETTER PREDICTIVE TEST THAN ONCOTYPE FOR BREAST CANCER

A new test, called EndoPredict, can predict the risk of a woman’s breast cancer spreading within 10 years of diagnosis more accurately than the current test approved by the National Institute for Health and Care Excellence (NICE). Also, research found that the results can be made available more quickly.

A study, published in the Journal of the National Cancer Institute, compared EndoPredict with Oncotype DX, the test currently approved for use by the NHS in England and Wales.

Both tests can predict whether breast cancer will spread in women with oestrogen receptor positive, HER2 negative (ER+/HER2-) disease. This is a sub-type of breast cancer that accounts for about two-thirds of all cases – more than 33,000 women in the UK are diagnosed with this form of breast cancer each year.

Women with ER+/HER2- breast cancer are given endocrine therapy after surgery to treat their cancer. They are also given chemotherapy if there is a reasonable risk of the cancer spreading to other organs (referred to as secondary or metastatic breast cancer). This is because if the cancer spreads to certain organs, it may not be possible to treat it and the cancer can become incurable. The National Institutes for Health and Care Excellence (NICE) approved the use of the Oncotype DX test in 2013 to help establish if breast cancer patients are at risk of their cancer spreading and should therefore have chemotherapy.

How the New Test Works

The new EndoPredict test analyses eight different genes found in a sample of a patient's tumour. This information, as well as the size of the patient's tumour and their nodal status – whether the cancer has spread from the breast to their lymph nodes – are then used to determine the patient's risk of their breast cancer spreading in the next 10 years.

An 'EPclin' score categorises patients into low- and high-risk groups. Patients placed in the high-risk group would be recommended to have chemotherapy, but those in the low-risk group could be spared this treatment – and the debilitating side effects associated with it.

More Accurate Test – and Faster Results

Professor Mitch Dowsett and Dr Richard Buus from The Institute of Cancer Research (ICR) and The Royal Marsden, and Professor Jack Cuzick from Queen Mary University of London, led the research, which was partly funded by the charity Breast Cancer Now.

The study found that:

• Only 5.8% of all patients identified as 'low risk' by EndoPredict developed secondary cancer compared with 10.1% of patients identified as 'low risk' by Oncotype DX
• Of the one-third of patients identified as having the lowest risks, those with low EndoPredict scores and whose disease hadn’t already spread to their lymph nodes, just 0.5% developed second breast cancer after 10 years compared to 7% of those tested by Oncotype DX

Dr Richard Buus, the study's lead author, says in a statement: "This study showed that a new test is more accurate than the current NHS standard test at detecting women at lowest risk of their breast cancer spreading to other parts of the body in the long term.… and [these women] could therefore be spared from undergoing chemotherapy often offered early on in treatment to reduce their risk."

Another advantage of using EndoPredict is that the tests can be analysed locally at qualified molecular pathology labs based in the UK, whereas Oncotype DX tests can be sent to only one qualified laboratory – which is based in the US. By the time samples are sent abroad for analysis, it can take up to 14 days to get the results back when using the Oncotype DX tests compared to just days when using EndoPredict.

At the moment, Oncotype DX is the only cost-effective test approved by NICE, but EndoPredict is currently available privately. However, regardless of which test is offered, patients should be reassured that both tests provide useful clinical information about potential recurrence of breast cancer.

In a statement, Baroness Delyth Morgan, chief executive at Breast Cancer Now, says: "Oncotype DX remains a valuable tool for both clinicians and patients. But we need to see the best and most cost-effective technologies made routinely available on the NHS, and this research suggests EndoPredict could be another step forward.

"Based on this strong evidence, we would encourage NICE to consider this technology for routine use on the NHS."