Men with prostate cancer are being given false hope by tests that underestimate the aggressiveness of their disease, a study suggests.
Researchers found that more than half of a group of men whose cancers were initially classified as slow-growing and confined turned out to have more dangerous tumours.
The findings, published in the British Journal Of Cancer, call into question the ability of experts to grade and stage prostate cancers on the basis of biopsy samples.
It also casts doubt on the "active surveillance" strategy of avoiding unnecessary radical treatment for patients with slow-growing prostate cancer.
Instead, these patients are often closely monitored but left alone until tests suggest their condition has worsened.
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Downpours keeping us on our toes today
The M20 in Kent has been closed in both directions after a pedestrian bridge allegedly collapsed on the motorway on Saturday.
The AA have warned of traffic jams and urged people to carry extra water in their vehicles because of the warm weather.