A pioneering test enabling breast cancer patients to find out their chances of recovery was unveiled by scientists.
New technology will predict with 80% accuracy a sufferer's chance of recovering, doctors claim.
The tool analyses networks of proteins in breast cancer tumours to determine a patient's best treatment options.
The breakthrough by doctors in Canada was welcomed by UK cancer charities.
Ed Yong, from Cancer Research UK, said: "Not all breast cancers are the same. By working out the differences between them at a molecular level, techniques like these could allow breast cancer patients to receive more personalised treatment from their doctor, but there's still a long way to go before we get to that point."
Analysis of more than 350 patients found those who survive breast cancer have a different organisation of the network of proteins within tumour cells.
The new testing tool, named DyNeMo, can be used to predict the outcome in a newly diagnosed breast cancer patient to assist clinicians in making informed decisions on treatment, scientists at Mount Sinai Hospital said.
Dr Jeff Wrana, writing in the journal Nature Biotechnology, said: "Our hope with this technology is to eventually provide individualised analysis to breast cancer patients and their oncologists so that they are better informed and empowered to select a treatment best suited to them."
The study was led by the Mount Sinai Hospital team and co-authored by researchers at the University of Toronto plus the London-based Institute for Cancer Research.
Dr Jim Woodgett added: "This research brings us one step closer to delivering individualised medicine in which healthcare professionals will be able to provide more accurate and personalised diagnoses and treatments."
Copyright Press Association