Certain breast cancer patients could be spared chemotherapy with new test…….November 2016

Chemotherapy is one of the most difficult and painful parts of cancer. Despite it proving to be greatly effective in treating cancer cells, due to the nature of the drugs involved it can be an incredibly uncomfortable process for women suffering from breast cancer. However, a new study published on 20 August 2016 in The New England Journal of Medicine has shown promise for one existing genomic test in greatly helping identify women with a low risk of recurrence of early-stage breast cancer, who would as a result have little to gain from undergoing chemotherapy, and might possibly be spared the treatment.

Genomic testing has existed for over a decade, and is used by doctors to provide information on how a specific cancer tumour is behaving. Genomic tests analyse a sample of the cancer tumour to see how active certain genes are, the activity level of which affects the behaviour of the cancer, including how likely it is to grow and spread.

The study, involving almost 6,700 women over five years across Europe with early-stage (Stages I and II) breast cancer, screened patients for 70 genetic variants which increase the risk of recurrence, using an existing genomic test called MammaPrint. It was found that amongst those women who were described at being at a ‘low genomic-risk’ following the MammaPrint test results, chemotherapy didn’t have much of an effect on their survival after 5 years. 94.4% of those women with early-stage breast cancer, and who didn’t go through chemotherapy, survived for over five years without further cancer. The comparable figure for those who went through chemotherapy is 95.9%, only a slight 1.5% difference. Given this small difference, the researchers conclude that it is safe for women with early-stage breast cancer, who are identified as being ‘low-risk’ by this test to skip chemotherapy. The results are thought to show that around 46% of women with newly diagnosed early-stage breast cancer risk might not need to go through chemotherapy following screening from this test.

The test itself – which costs around £2,000 is currently only available privately – is developed by Agendia, who are currently in discussions with the National Institute of Health and Care Excellence (Nice) about providing the test on the NHS. Dr Maggie Cheang, Senior Staff Scientist at The Institute of Cancer Reasearch, said:

“The trial clearly shows that patients with a low risk, defined by both clinical factors and the MammaPrint test, have an excellent prognosis and can be safely spared chemotherapy. However, in the group of patients that are at clinically high risk but MammaPrint low, the benefit of chemotherapy and the survival beyond 5 years is still unclear. In this group, longer follow-up and future studies are needed before we decide to forego adjuvant chemotherapy.”

To read more about the study, please see The New York Time’s report on it here, or see The Telegraph’s piece here