I found this interesting discussion on over and under diagnosis of breast cancer and how to avoid it. Its definitely worth the read.
The big take away I found in the article is that the best way to avoid overdiagnosis is to get screening done at a breast center where the radiologists read mammograms daily. Through their jobs, they see many more breast images than other radiologists who are not as specialized and much more apt to correctly diagnose breast cancer.
Also, better education of patients and oncologists will also help with preventing over-treatment. Often the first reaction at a cancer diagnosis is 'get rid of it now and make sure it doesn't come back!' Fear takes over and the reaction of a patient goes instantly to get rid of it.
But maybe if the patient takes time to educate themselves on treatment possibilities the fear can be controlled. And the doctor is educated enough to provide the support to help the patient make the best choices and not the impulsive choices. Then the chance of over treatment can be reduced.
I think that this issue of over treatment and over diagnosis for many ailments needs more awareness and focus. We need better trained medical personnel who are able to better read screening images and provide better diagnoses. We also need additional training for medical personnel to help patients make better decisions. Finally we need more information available for patients to reduce the fear at diagnosis so they are able to make better decisions.