Much investment has been put into facilities for early cancer diagnosis. It is difficult to know how successful this investment has been. New facilities for rapid investigation in the UK have not reduced mortality, and may cause delays in diagnosis of patients with low-risk, or atypical, symptoms. In part, the failure of new facilities to translate into mortality benefits can be explained by five misconceptions. These are described, along with suggested research and organisational remedies. The first misconception is that cancer is diagnosed in hospitals. Consequently, secondary care data have been used to drive primary care decisions. Second, GPs are thought to be poor at cancer diagnosis, yet the type of education on offer to improve this may not be what is needed. Third, symptomatic cancer diagnosis has been downgraded in importance with the introduction of screening, yet screening identifies only a small minority of cancers. Fourth, pressure is put on GPs to make referrals for those with an individual high risk of cancer - disenfranchising those with 'low-risk but not no-risk' symptoms. Finally, considerable nihilism exists about the value of early diagnosis, despite considerable observational evidence that earlier diagnosis of symptomatic cancer is beneficial.