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Prostate, Lung, Colon, and Ovary Prospective Study

PLCO is a large NCI trial (n=155,000) that evaluated screening for early detection of prostate, lung, colon, and ovarian cancer. In addition to these aims, it is widely used as an observational cohort for early detection and etiologic studies.

Starting in 1993, participants were randomized in equal proportions to an intervention arm (n=77,500), which received trial screening, or to a control arm (n=77,500), which received usual care. Intervention arm participants provided annual blood samples for six years, whereas control arm participants provided a single oral wash sample. All participants have been followed for cancer incidence and mortality since enrollment in 1993.

The large size of this cohort and availability of serial samples make PLCO a unique and widely used resource for etiologic and early detection studies. More than 290 projects have been approved to use the biological resources in the cohort so far, as have more than 720 data-only projects and and 54 projects to use PLCO images. PLCO participates in more than 30 consortia and has resulted in more than 1000 publications to date. Highlights include playing a key role in the discovery of nearly three-quarters of the known genomic susceptibility loci for cancer identified in genome-wide association studies; studies of acquired mutations; and studies of obesity and physical activity.

Learn more about the Prostate, Lung, Colon, and Ovary Prospective Study.

For more information, contact Dr. Steven Moore.