Screening is identifying health people at risk of a disease or condition, to provide the benefit of reducing risk and future complications.
One example I have is the finding of MGUS (monoclonal gammopathy of undetermined significance), a precursor protein linked to mulptiple myeloma.
It isn't screened for but can be found incidentally, and indicates a risk of myeloma.
However, once found in the US it is disclosed, monitored and thoroughly investigated, most likely due to privatisation of health care.
However, in finding this protien, the outcomes are not very beneficial to patients. There is no chance that the protien will develop into cancer, if it does develop into myeloma it does so at 1-2% a year. There is no treatment for this precurser stage, apart from constant monitoring. There are several other reasons why MGUS may be elevated in people (age, infections, rheumatoid arthritis).
Therefore, finding for this protien doesn't have many, if any benefits. I would say it causes more harm. If it is found incidentally the patient is informed and there is the worry that this protien may develop into a cancer at 1-2% a year. This causes immense anxiety which increases over decades as the risk adds up.
Monitoring MGUS means routine blood tests, bone scans, x-rays etc, all with their own individual risks and repeated anxiety. Of course in the US these interventions mean money.
If it does develop into myeloma, which is a very small chance, other than catching it early through monitoring it, the cancer will still develop.
Therefore, are there benefits of informing patients about MGUS and their risk of myeloma? Other than the worry and stress of a small chance of developing myeloma.