JAMA Network | JAMA | Overdiagnosis and Overtreatment in Cancer: An Opportunity for Improvement
Viewpoint | July 29, 2013
Overdiagnosis and Overtreatment in CancerAn Opportunity for Improvement FREE ONLINE FIRST
Published online July 29, 2013
Over the past 30 years, awareness and screening have led to an emphasis on early diagnosis of cancer. Although the goals of these efforts were to reduce the rate of late-stage disease and decrease cancer mortality, secular trends and clinical trials suggest that these goals have not been met; national data demonstrate significant increases in early-stage disease, without a proportional decline in later-stage disease. What has emerged has been an appreciation of the complexity of the pathologic condition called cancer. The word “cancer” often invokes the specter of an inexorably lethal process; however, cancers are heterogeneous and can follow multiple paths, not all of which progress to metastases and death, and include indolent disease that causes no harm during the patient’s lifetime. Better biology alone can explain better outcomes. Although this complexity complicates the goal of early diagnosis, its recognition provides an opportunity to adapt cancer screening with a focus on identifying and treating those conditions most likely associated with morbidity and mortality.
Changes in cancer incidence and mortality1 reveal 3 patterns that emerged after inception of screening (Table). Screening for breast cancer and prostate cancer appears to detect more cancers that are potentially clinically insignificant.4 Lung cancer may follow this pattern if high-risk screening is adopted.5 Barrett esophagus and ductal carcinoma of the breast are examples for which the detection and removal of lesions considered precancerous have not led to lower incidence of invasive cancer. In contrast, colon and cervical cancer are examples of effective screening programs in which early detection and removal of precancerous lesions have reduced incidence as well as late-stage disease. Thyroid cancers and melanoma are examples for which screening has expanded and, along with it, the detection of indolent disease.