title: Early detection of cancer: past, present, and future.
abstract: Screening in both healthy and high-risk populations offers the opportunity to detect cancer early and with an increased opportunity for treatment and curative intent. Currently, a defined role for screening exists in some cancer types, but each screening test has limitations, and improved screening methods are urgently needed. Unfortunately, many cancers still lack effective screening recommendations, or in some cases, the benefits from screening are marginal when weighed against the potential for harm. Here we review the current status of cancer screening: we examine the role of traditional tumor biomarkers, describe recommended imaging for early tumor surveillance, and explore the potential of promising novel cancer markers such as circulating tumor cells (CTC) and circulating tumor DNA. Consistent challenges for all of these screening tests include limited sensitivity and specificity. The risk for overdiagnosis remains a particular concern in screening, whereby lesions of no clinical consequence may be detected and thus create difficult management decisions for the clinician and patient. If treatment is pursued following overdiagnosis, patients may be exposed to morbidity from a treatment that may not provide any true benefit. The cost-effectiveness of screening tests also needs to be an ongoing focus. The improvement of genomic and surveillance technologies, which leads to more precise imaging and the ability to characterize blood-based tumor markers of greater specificity, offers opportunities for major progress in cancer screening.
authors.affiliation: From the Department of Pediatrics and Huntsman Cancer Institute, University of Utah, Salt Lake City, UT; Stanford Cancer Center, Stanford University, Palo Alto, CA; Walter and Eliza Hall Institute, Ludwig Cancer Research, Royal Melbourne and Western Hospital, Melbourne, Australia.
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Schiffman
authors.affiliation: From the Department of Pediatrics and Huntsman Cancer Institute, University of Utah, Salt Lake City, UT; Stanford Cancer Center, Stanford University, Palo Alto, CA; Walter and Eliza Hall Institute, Ludwig Cancer Research, Royal Melbourne and Western Hospital, Melbourne, Australia.
authors.forename: Paul G
authors.initials: PG
authors.lastname: Fisher
authors.affiliation: From the Department of Pediatrics and Huntsman Cancer Institute, University of Utah, Salt Lake City, UT; Stanford Cancer Center, Stanford University, Palo Alto, CA; Walter and Eliza Hall Institute, Ludwig Cancer Research, Royal Melbourne and Western Hospital, Melbourne, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Gibbs
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism; D004273:DNA, Neoplasm; D003952:Diagnostic Imaging; D055088:Early Detection of Cancer / Q000379:methods / Q000639:trends; D006801:Humans; D009369:Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D009360:Neoplastic Cells, Circulating
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm