Cancer Screening is of little benefit in persons with dementia but can cause very serious harms. Older persons with dementia have limited life expectancies which makes any benefit from cancer screening very unlikely. This is because cancer screening works by identifying a cancer many years (generally at least 5-10 years) before it would threaten health. But cancer screening tests cause lots of burdens when given to persons with dementia. The test itself often leads to discomfort, distress, and agitation. Even worse, the results often demand a further cascade of tests that lead to more serious side effects. Sometimes it leads to highly morbid treatment for an asymptomatic cancer that would have never caused any problems in the patient's remaining life span. The vast majority of experts in cancer screening and geriatrics agree that cancer screening in persons with dementia is a really really bad idea. So, you would think we would just step doing it. But think again.