48116
document
Lead-time in the European Randomised Study of Screening for Prostate Cancer . BACKGROUND Lead-time is defined as the time by which screening advances the diagnosis compared with absence of screening . A sufficiently long lead-time needs to be achieved so that cancer can be detected while still curable . A very short lead-time may indicate poor sensitivity of the screening test , while a very long lead-time suggests overdiagnosis . MATERIAL AND METHODS In the first screening round , a total of 56,294 men aged 55-74 years were screened with serum prostate specific antigen ( PSA ) in five countries of the European Randomised Study of Screening for Prostate Cancer ( ERSPC ) with an overall detection rate ( prevalence ) of 2.8 % ( 1972 prostate cancers ) . Prostate cancer incidence among 92,142 men randomly allocated to the control arm of the trial was also assessed . Lead-time was estimated as the time required to accumulate a similar cumulative risk of prostate cancer in the control arm to the detection rate in the intervention arm , i.e . from the ratio of detection rate ( prevalence of screen-detected cases ) and expected incidence ( cumulative risk ) . RESULTS Using a serum PSA cut-off of 4 ng/ml , the mean lead-time in the whole study population was estimated as 6.8 years ( 95 % confidence interval ( 95 % CI ) 7.9-8.4 ) . It was 8 years in The Netherlands , 6 in Sweden and Finland , 5 in Italy and 4 in Belgium . The mean lead-time was similar , 6-7 years , at ages 50-64 years , but close to 8 years among men aged 65-74 years . A lower PSA cut-off level of 3 ng/ml used in Sweden and The Netherlands prolonged the mean lead-time by approximately 1 year . Lead-time based on advanced prostate cancer only was slightly shorter , mean 5.3 years ( 95 % CI 4.6-6.0 ) . The lead-time for the second screening round was slightly shorter than that for the first ( 5.9 , 95 % CI 5.4-6.4 ) , reflecting a similar relation between detection rate and control group incidence . CONCLUSION The lead-time for prostate cancer found in ERSPC substantially exceeded that found for breast , cervical and colorectal cancer screening . One round of prostate cancer screening can advance clinical diagnosis by 4-8 years . Overdiagnosis or detection of non-progressive tumours may contribute substantially to the lead-time .
48117
Intervention_Pharmacological
serum prostate specific antigen ( PSA )
48118
Outcome_Other
Lead-time
48119
Outcome_Other
mean lead-time
48120
Outcome_Other
mean lead-time
48121
Outcome_Physical
PSA cut-off level
48122
Outcome_Physical
Lead-time based on advanced prostate cancer
48123
Outcome_Other
lead-time for the second screening round
48124
Outcome_Other
lead-time
48125
Participant_Condition
Prostate Cancer .
48126
Participant_Sample-size
56,294
48127
Participant_Sex
men
48128
Participant_Age
aged 55-74 years
48129
Participant_Condition
Prostate Cancer
48130
Participant_Condition
Prostate cancer
48131
Participant_Sample-size
92,142
48132
Participant_Sex
men