Cancer can cause many different symptoms, some subtle and some not at all subtle. Some symptoms develop early in the course of cancer and are therefore important warning signs that should be evaluated by a doctor. Other symptoms develop only after the cancer progresses and are therefore not helpful in the early detection of cancer. Still other symptoms, such as nausea, loss of appetite, fatigue, and vomiting, may be the result of the cancer or its treatment, may be warning signs, or may even result from conditions other than cancer. Some symptoms occur with many or almost all cancers, and others are specific to the type of cancer and where it is growing.
Screening programs allow early detection and diagnosis of cancer. The earlier cancer is diagnosed, the more effective treatment is likely to be.
Last full review/revision October 2006 by Matthew G. Fury, MD