title: Overdiagnosis in cancer.
abstract: This article summarizes the phenomenon of cancer overdiagnosis-the diagnosis of a "cancer" that would otherwise not go on to cause symptoms or death. We describe the two prerequisites for cancer overdiagnosis to occur: the existence of a silent disease reservoir and activities leading to its detection (particularly cancer screening). We estimated the magnitude of overdiagnosis from randomized trials: about 25% of mammographically detected breast cancers, 50% of chest x-ray and/or sputum-detected lung cancers, and 60% of prostate-specific antigen-detected prostate cancers. We also review data from observational studies and population-based cancer statistics suggesting overdiagnosis in computed tomography-detected lung cancer, neuroblastoma, thyroid cancer, melanoma, and kidney cancer. To address the problem, patients must be adequately informed of the nature and the magnitude of the trade-off involved with early cancer detection. Equally important, researchers need to work to develop better estimates of the magnitude of overdiagnosis and develop clinical strategies to help minimize it.
authors.affiliation: Department of Veterans Affairs Medical Center, White River Junction, VT 05009, USA. h.gilbert.welch@dartmouth.edu
authors.forename: H Gilbert
authors.initials: HG
authors.lastname: Welch
authors.forename: William C
authors.initials: WC
authors.lastname: Black
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood*; D001706:Biopsy; D001943:Breast Neoplasms / Q000175:diagnosis / Q000453:epidemiology; D018450:Disease Progression; D055088:Early Detection of Cancer; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis / Q000453:epidemiology; D008297:Male; D008327:Mammography; D008403:Mass Screening / Q000379:methods / Q000639:trends; D009367:Neoplasm Staging; D009369:Neoplasms / Q000175:diagnosis* / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000453:epidemiology; D016032:Randomized Controlled Trials as Topic; D018426:SEER Program; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000453:epidemiology; D014481:United States / Q000453:epidemiology
chemical_list: D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen