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National Cancer Institute, Cancer Screening Overview, 2012. What is screening? Screening is the name given to a range of tests that can detect cancer at an early stage before symptoms appear Finding cancer early usually means it is easier to treat/cure By the time symptoms appear, the cancer may have grown and spread and therefore be more difficult to treat/cure Breast Cancer Screening Evidence: NCI Screening Overview 2012 (p 1) National Cancer Institute, Cancer Screening Overview, 2012.

Screening: the rationale For screening to be effective, two requirements must be met: A test or procedure must be available to detect cancers earlier than if the cancer were detected as a result of the development of symptoms ! Evidence must be available that treatment initiated earlier as a consequence of screening results in an improved outcome Evidence: NCI Cancer Screening HCP 2012 (p2) ! National Cancer Institute, Cancer Screening HCP, 2012.

Patient‘s blood sample Screening tests A variety of tests are used in cancer screening: Physical exam and history: check general health and review medical history Laboratory tests: investigate samples of tissue, blood, urine, etc. Imaging: visualise the insides of the body using e.g. x-ray, ultrasound, CT, MRI, etc Molecular tests: look for specific mutations that are linked to some types of cancer Cervical Cancer Screening Normal Pap smear Abnormal Biopsy Evidence: NCI Cancer Screening Overview 2012 (p1) Pathology Patient‘s blood sample or tissue sample Proteomic profile Genomic profile National Cancer Institute, Cancer Screening Overview, 2012. Artwork originally created for the National Cancer Institute. Reprinted with permission of the artist, Jeanne Kelly. Copyright 2013.

Screening: pros and cons Reduction in cancer deaths 3–35% of premature deaths due to cancer could be avoided with screening Improved outcomes (does not apply in all cases) Cons Some screening procedures carry their own risks False negative results – patient wrongly assured there is no problem False positive results – patient may receive treatment they do not need Evidence: NCI Cancer Screening HCP 2012 (p1, 3) National Cancer Institute, Cancer Screening HCP, 2012.

Screening and high risk populations By focusing on high-risk populations, screening resources can be better applied Patients with a personal history/strong family history of cancer are deemed to be high-risk The ability to test for specific genetic mutations has further refined the identification of high-risk patients Heredity and cancer All Breast Cancer Patients Inherited factor(s) Other factor(s) Genes and Cancer Chromosomes are DNA molecules Evidence: NCI Cancer Screening HCP 2012 (p2) Chemicals Radiation Heredity Viruses National Cancer Institute, Cancer Screening HCP, 2012. Artwork originally created for the National Cancer Institute. Reprinted with permission of the artist, Jeanne Kelly. Copyright 2013.