{"entity":{"id":"plco-prostate","kind":"trial","name":"PLCO, prostate component (Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial)","aka":["PLCO","PLCO prostate","Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial"],"tldr":"The American screening trial that found no benefit, and the reason is the trial itself: half the men in the group that was supposed to go unscreened were getting PSA tests from their own doctors.","summary":"PLCO randomised 76,693 men at ten United States centres between 1993 and 2001 to annual prostate-specific antigen testing for six years with digital rectal examination for four years, or to usual care. Compliance in the screened group was 85 percent for PSA and 86 percent for rectal examination.\n\nThe finding that matters for reading the result is in the control group: PSA testing there rose from 40 percent in the first year to 52 percent in the sixth, with rectal examination in 41 to 46 percent. The trial therefore compared organised annual screening with widespread opportunistic screening, not with no screening at all.\n\nAfter seven years the incidence of prostate cancer was 116 per 10,000 person-years in the screened group against 95 in the control group, and the death rate was 2.0 against 1.7 per 10,000 person-years, a rate ratio of 1.13 that was not significant. The ten-year data, 67 percent complete at the time of the report, were consistent.","status":"negative","asOf":"2026-09-25","links":[{"label":"PLCO prostate mortality (New England Journal of Medicine 2009)","url":"https://doi.org/10.1056/NEJMoa0810696"},{"label":"ClinicalTrials.gov NCT00002540","url":"https://clinicaltrials.gov/study/NCT00002540"}],"tags":[],"related":[],"cancers":["prostate"],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["psa","overdiagnosis"],"trials":["erspc"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT00002540","phase":"3","setting":"Population screening: men randomised at ten United States centres to annual PSA testing for six years with digital rectal examination for four, or to usual care, with death from prostate cancer as the outcome","sponsor":"National Cancer Institute","result":"Prostate cancer death rate 2.0 against 1.7 per 10,000 person-years, rate ratio 1.13 (95 percent confidence interval 0.75 to 1.70), not significant; control-group PSA testing rose from 40 to 52 percent over the six screening years.","yearReported":2009,"enrolledBasis":"registry","outcomes":[{"endpoint":"Death from prostate cancer at 7 years","primary":true,"unit":"per 10,000 person-years","arms":[{"name":"Annual PSA and digital rectal examination","n":38343,"value":2,"note":"50 deaths."},{"name":"Usual care","n":38350,"value":1.7,"note":"44 deaths."}],"hr":1.13,"ci":[0.75,1.7],"source":"https://doi.org/10.1056/NEJMoa0810696"},{"endpoint":"Prostate cancer incidence at 7 years","unit":"per 10,000 person-years","arms":[{"name":"Annual PSA and digital rectal examination","n":38343,"value":116,"note":"2,820 cancers; rate ratio 1.22 (1.16 to 1.29)."},{"name":"Usual care","n":38350,"value":95,"note":"2,322 cancers."}],"source":"https://doi.org/10.1056/NEJMoa0810696"}],"replication":"ERSPC, reported in the same issue of the same journal on the same day, found a 20 percent reduction in prostate cancer mortality. The difference between the two is usually attributed to PLCO's contaminated control arm, its shorter screening interval and its higher PSA threshold for biopsy."},"route":"/trials/plco-prostate/","neighbours":{"cancer":[{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"}],"term":[{"id":"overdiagnosis","kind":"term","name":"Overdiagnosis","route":"/terms/overdiagnosis/"},{"id":"psa","kind":"term","name":"PSA (prostate-specific antigen)","route":"/terms/psa/"}],"trial":[{"id":"erspc","kind":"trial","name":"ERSPC (European Randomized Study of Screening for Prostate Cancer)","route":"/trials/erspc/"}]}}