The importance of early symptom recognition in the context of early detection and cancer survival.

Since there is evidence that stage is an important prognostic factor in cancer, interventions aimed at 'down-staging' are part of a comprehensive cancer control approach. Besides organised screening programmes, raising awareness of detectable signs and symptoms is recommended. A precise definition of early cancer signs and symptoms, however, is lacking and there has also been no systematic review regarding the impact of awareness raising interventions on cancer outcomes. We reviewed the scientific medical literature to assess the consistency and availability of a definition for early cancer symptoms as well as to assess the impact of early cancer diagnosis on survival. Although early diagnosis is an important factor for cancer survival, other considerations such as the cancer profile of a country, the characteristics of cancer types and the availability of devices for diagnosis should be taken into account in promoting early cancer detection. There is a clear need for research to categorize cancer types according to early symptoms in order to increase comparability of studies in this field and to provide guidance for health personnel in primary care settings in low income regions.