Scientists have devised a simple test for an earlier and more accurate warning of returning bladder cancer than existing methods.

Researchers from the University Hospital of Lyon tested the urine of 348 bladder cancer patients for a faulty protein called TERT, and this was able to predict when the cancer was about to return in more than 80 percent of patients. The standard method, called cytology, detected the return in only 34 percent of patients.

The new test detected bladder cancers that had not spread to the muscle wall, earlier than cytology, potentially helping doctors to start treatment sooner and before symptoms appear.

A further benefit is that the new test distinguished cancer from urinary tract infections. The discovery also suggests that further research is needed to understand more about the role TERT faults play in bladder cancer.

Larger trials are now needed to see if this information could help more people survive by catching bladder cancer's return at its earliest stage.