The researchers explained that this warning sign is seen in approximately 85 percent of patients with the disease.
They explained that haematuria is triggered by a direct haemorrhage of the tumour, which describes bleeding.
Despite blood in your pee being considered a key sign of bladder cancer, haematuria can also be caused by a variety of benign conditions like urinary tract infections.
However, you should visit your GP if you have blood in your urine, so the cause can be properly investigated, the NHS advises.
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