The ProtecT trial: What can we expect?

Profound changes in the detection of prostate cancer have occurred since prostate-specifi c antigen (PSA) was introduced as a biomarker test for prostate cancer. Instead of the disease being detected at an advanced stage when symptoms caused by invasive growth emerged—with palliative treatment the main option—prostate cancer is diagnosed early on in the disease course.

However, not only were potentially lethal tumours detected at an early, treatable stage, but also many non-lethal tumours were diagnosed. This over-diagnosis leads to substantial overtreatment with its associated side-effects. Therefore, whether treatment of early detected, localised cancers will result in a benefit or mainly cause harm is unclear.