GPs should investigate suspected bladder cancer in any patient over 40 with visible haematuria, say UK researchers.
Their analysis looked at primary care data from 29,000 patients, including almost 5,000 diagnosed with bladder cancer, and highlighted four symptoms and three laboratory tests that were independently associated with the condition.
Haematuria was the most predictive symptom, and the other symptoms they found with a positive predictive value of more than 2% were dysuria, abdominal pain and constipation.
Raised creatinine, inflammatory markers and white blood cell counts were all also independent predictors. The data also showed that urinary tract infections were an important marker.
But in the first study to look at symptoms other than haematuria in primary care, they suggest GPs use a risk chart to discuss with patients whether a referral in certain circumstances is warranted.
Study leader Professor Willie Hamilton, professor of primary care diagnostics at Peninsula College of Medicine and Dentistry, said a classic cause of delay in investigation for bladder cancer was repeated urinary tract infections that were successfully treated, but that may be masking something else.
He said: ‘This can be a clinical trap, especially in the elderly. We should perhaps be quicker to think of cancer when a UTI isn't responding in the expected way.'
He added the new risk tool would help GPs work out the odds of bladder cancer when patients had a few minor symptoms presenting together.
