Cancer screening comes under scrutiny during the CRUK Cambridge Centre Early Detection Programme event Cancer overdiagnosis: what is it? on 26th October. Speakers include Dr Stephen John, Hatton Lecturer in the Philosophy of Public Health and Dr Maryon McDonald, Fellow in Social Anthropology at Robinson College, Cambridge, who discuss some of the issues around cancer screening and diagnosis.
Commenting on the intensely personal and politically complicated and controversial issues around overdiagnosis, Dr John said: “Because early-stage cancers are far easier to treat than late-stage cancers, there are excellent reasons to try to detect cancerous growths as soon as possible. Unfortunately, there is also a problem: the earlier we diagnose a growth, the less certain we can be that the growth will go on to cause illness or death. We risk ‘overdiagnosing’ and therefore ‘overtreating’ patients.
“This gives rise to a series of problems: how should we balance the harms of overtreating some against the benefits of helping others? Answering this is difficult because we may never know who was helped and who was harmed by our intervention: once we have removed a cancerous growth, there is no way of knowing whether, if left untreated, it would have caused symptoms. ‘Cancer survivors’ who celebrate the fact that their lives were saved by screening might, in fact, never have needed treatment in the first place. This fact raises tricky questions about how to apply everyday moral frameworks to early detection; does the core principle of medical ethics, ‘first, do no harm’, make sense when no-one will ever know that they were harmed?
“At the same, screening and early detection decisions are not only about statistics, but they affect individuals. Some writers claim that constant screening and testing can cause new illnesses; more generally, screening changes our self-identity by telling apparently healthy people that they are, in fact, ill. In screening, then, we not only cure, but create ill people.”
Please click here to read the whole press release from the Festival of Ideas.