PSA Testing

PSA (prostate-specific antigen) is a protein made by the prostate and measured in a blood sample. It is specific to the prostate, but not to cancer: levels also rise with an enlarged prostate, infection, recent catheterisation, and sometimes after vigorous cycling or ejaculation.

Testing can find prostate cancer before it causes symptoms, when treatment options are widest. Large European screening studies have shown fewer deaths from prostate cancer among men invited for PSA testing, and modern practice — using MRI before biopsy, and monitoring rather than treating low-risk disease — reduces the harms that earlier programmes caused.

PSA testing also finds cancers that would never have caused harm, and a raised result leads to further tests that carry their own risks and anxiety. This is why national bodies generally recommend an informed discussion rather than routine screening of all men.

A discussion about testing is often suggested earlier for men with:

• a father or brother diagnosed with prostate cancer, particularly at a younger age
• a family history of breast, ovarian or pancreatic cancer, or a known BRCA2 change
• African or Afro-Caribbean ancestry
• urinary symptoms that need assessment in their own right

There is no single right answer. What matters is understanding what a raised result would mean for you, and whether you would want the tests that follow. If you would not want treatment or monitoring under any circumstances, testing may be of limited value to you.

A single raised reading is usually repeated before anything else is done, and infection is excluded. Where the level remains raised, a prostate MRI is generally the next step, and a biopsy is considered according to the MRI findings and your PSA density. This is covered in detail on the raised PSA page, and the disease itself on the prostate cancer page.