Mixed messages on DNA test a risk to bowel cancer screening, Australia
The advice is aimed at addressing 'mixed messages' in the Australian media about a new blood test for bowel cancer, which is only a third as sensitive for advanced adenomas and stage one cancer as immunochemical FOBT.
Cancer Council Australia CEO, Professor Ian Olver, said the evidence clearly showed that FOBT was the most effective tool for bowel cancer screening.
"New biomarkers for major disease usually attract media coverage, but it's important to remain focused on the evidence," Professor Olver said. "As the developers of the DNA test have noted, it could have a role as an adjunct to FOBT.
"The evidence, including major pilot programs in Australia and outstanding results from the FOBT-based national program, overwhelmingly supports FOBT as the best population screening tool. We cannot risk having this message confused.
"Patients who are 50, 55, 60 and 65 are eligible for the National Bowel Cancer Screening Program and should be encouraged to participate. Patients over 50 who fall between those ages should take a two-yearly FOBT until the Government finishes extending the screening program to everyone aged 50 to 74 by 2020."
Professor James St John, gastro-enterologist, researcher and longstanding member of Cancer Council's National Cancer Screening Committee, said the FOBT-based national program, when fully implemented, had the potential to prevent 70,000 bowel cancer deaths over the next four decades.
"Identifying cancer and precancerous conditions early is the key to effective screening," Professor St John said.
"The literature shows immunochemical FOBTs are around three times more sensitive for advanced adenomas and stage one bowel cancer than the blood-based DNA test. On a population basis, that can make an enormous difference to mortality and morbidity if people whose cancer could have been detected by FOBT have it missed by the blood test.
"The main focus needs to be on rolling out the full two-yearly FOBT screening program and encouraging participation via targeted communications. The more people screen for bowel cancer with FOBT, the more lives will be saved.
"We would welcome the addition of a blood-based test if it assists with surveillance, but the focus has to be on what works best to save the most lives - and that is FOBT."