Men from lower-class backgrounds are missing out on a test that could help them get early treatment for prostate cancer, it has been claimed.
The Prostate Cancer Charity said many doctors oppose access to the prostate-specific antigen (PSA) test, which helps diagnose the most prevalent form of cancer affecting men in the UK.
More than 10,000 men die from prostate cancer in the UK each year, with around 35,000 diagnosed with the disease.
But one in five GPs disagree that men should have access to the test at all, according to a survey of doctors carried out by the charity.
And a quarter said they would not discuss the issue with men most likely to be affected by the cancer - those over 50 - if it had not been brought up by the patient first.
Further research by the charity showed around half of men aged between 50 and 70 were unaware of their right to request a PSA test from their doctor, with those from a lower socio-economic group less likely to know their rights.
A raised PSA level may indicate prostate cancer, but it is not a specific test for prostate cancer.
John Neate, chief executive of the charity, explained: "Men are facing a totally unacceptable two tier system between those who are educated and confident to enough to ask for the PSA test and those who remain in the dark."