New test may reduce chemotherapy use in breast cancer
Professor Mitch Dowsett and colleagues have published early trial data showing that a test they developed, IHC4, could identify patients at sufficiently low risk of their breast cancer returning after surgery that they may be spared chemotherapy.
The team, led by scientists in the ICR’s Breakthrough Breast Cancer Research Centre and clinicians at The Royal Marsden NHS Foundation Trust, compared the diagnosis of 101 ER positive breast cancer patients using two current standard diagnostic tools and the new IHC4 test.
The results suggested that almost half of ER positive breast cancer patients currently classified as at intermediate risk of recurrence would be downgraded to low risk by the test. This would mean they would potentially safely avoid chemotherapy and its toxic side effects.
They found 15 of 26 patients classified as intermediate risk by one existing test, called AoL (Adjuvant Online), would have been reclassified as low risk using IHC4. Twenty-four of 59 patients classified as intermediate risk by the second existing test, called NPI (Nottingham Prognostic Index), would have been moved to the lower-risk category using IHC4. Around 13 patients using this second test were also reclassified as high risk.
The test is already being considered for use on the NHS and has the potential to be very cost-effective.
