The Number of Screening Cycles Needed to Reduce Prostate Cancer Mortality in the Finnish Section of the European Randomized Study of Prostate Cancer (ERSPC)

Screening history and risk of death from prostate cancer: a nested case-control study within the screening arm of the Finnish Randomized Study of Screening for Prostate Cancer (FinRSPC)

PURPOSE

We assessed the risk of death from prostate cancer (PCa) in relation to men's screening histories, i.e., screening attendance among men who were offered screening.

METHODS

Men in the Finnish Randomized Study of Screening for Prostate Cancer (FinRSPC) screening arm were invited to up to three screening rounds with the serum prostate-specific antigen (PSA) test at 4-year intervals during 1996-2007. Case subjects (n = 330) were men who died from PCa. Each case was matched to five controls (n = 1544) among the men who were free of PCa. Screening history was defined as (1) never/ever attended screening prior to the case diagnosis; (2) attended at the first screening round; and (3) recency of screening, calculated as the time from last screening attendance to the date of case diagnosis. The association between screening history and the risk of death from PCa was estimated by odds ratios (OR) with 95% confidence intervals (CI) using conditional logistic regression.

RESULTS

Having ever attended screening versus never attended was associated with a reduced risk of PCa death (OR 0.60, 95% CI 0.45-0.81) and a similar association was found for those attended (versus not attended) the first screening round (OR 0.67, 95% CI 0.51-0.87). The effect by time since last screen for the risk of PCa death was significantly lower 2-7 years since last screen.

CONCLUSION

Among men invited to screening, subjects who attended any PSA screening during the previous 19 years had a 40% reduction in PCa mortality compared to non-screened men.

Health-Related and Psychosocial Factors Associated with Prostate Cancer Stage at Diagnosis among Males Participating in Alberta's Tomorrow Project

Prostate cancer (PCa) stage at diagnosis is an important predictor of cancer prognosis. In Canada, over one-quarter of males are diagnosed with advanced-stage PCa. Studies have identified several factors associated with PCa stage at diagnosis; however, evidence from Canada is limited. This study aimed to examine associations between sociodemographic characteristics, health history, health practices, and psychosocial factors and PCa stage at diagnosis among males participating in Alberta's Tomorrow Project (ATP), a prospective cohort in Alberta, Canada. The study included males aged 35-69 years who developed PCa until January 2018. Factors associated with PCa stage at diagnosis were examined using partial proportional odds (PPO) ordinal regression models. A total of 410 males were diagnosed with PCa over the study period. A higher number of lifetime prostate-specific antigen tests were associated with earlier-stage PCa (OR 0.91, p = 0.02, 95% CI 0.83-0.99), while higher abdominal circumference (OR 1.02, p = 0.05, 95% CI 1.00-1.03), lower social support (OR 2.34, p < 0.01, 95% CI 1.31-4.17), and having children (OR 2.67, p < 0.01, 95% CI 1.38-5.16) were associated with later-stage disease. This study identified factors previously found in the literature as well as novel factors associated with PCa stage at diagnosis, which can help inform targets for cancer prevention programs to improve PCa prognosis.

A Detailed Evaluation of the Effect of Prostate-specific Antigen-based Screening on Morbidity and Mortality of Prostate Cancer: 21-year Follow-up Results of the Rotterdam Section of the European Randomised Study of Screening for Prostate Cancer

BACKGROUND

Considering the long natural history of prostate cancer (PCa), long-term results of the European Randomised Study of Screening for PCa (ERSPC) are crucial.

OBJECTIVE

To provide an update on the effect of prostate-specific antigen (PSA)-based screening on PCa-specific mortality (PCSM), metastatic disease, and overdiagnosis in the Dutch arm of the ERSPC.

DESIGN, SETTING, AND PARTICIPANTS

Between 1993 and 2000, a total of 42376 men, aged 55-74 yr, were randomised to a screening or a control arm. The main analysis was performed with men aged 55-69 yr (n = 34831). Men in the screening arm were offered PSA-based screening with an interval of 4 yr.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Intention-to-screen analyses with Poisson regression were used to calculate rate ratios (RRs) of PCSM and metastatic PCa.

RESULTS AND LIMITATIONS

After a median follow-up of 21 yr, the RR of PCSM was 0.73 (95% confidence interval [CI]: 0.61-0.88) favouring screening. The numbers of men needed to invite (NNI) and needed to diagnose (NND) to prevent one PCa death were 246 and 14, respectively. For metastatic PCa, the RR was 0.67 (95% CI: 0.58-0.78) favouring screening. The NNI and NND to prevent one metastasis were 121 and 7, respectively. No statistical difference in PCSM (RR of 1.18 [95% CI: 0.87-1.62]) was observed in men aged ≥70 yr at the time of randomisation. In the screening arm, higher rates of PCSM and metastatic disease were observed in men who were screened only once and in a selected group of men above the screening age cut-off of 74 yr.

CONCLUSIONS

The current analysis illustrates that with a follow-up of 21 yr, both absolute metastasis and mortality reduction continue to increase, resulting in a more favourable harm-benefit ratio than demonstrated previously. These data do not support starting screening at the age of 70-74 yr and show that repeated screening is essential.

PATIENT SUMMARY

Prostate-specific antigen-based prostate cancer screening reduces metastasis and mortality. Longer follow-up shows fewer invitations and diagnoses needed to prevent one death, a positive note towards the issue of overdiagnosis.

Outcomes of Screening for Prostate Cancer Among Men Who Use Statins

Importance

Prostate-specific antigen (PSA) screening for prostate cancer has resulted in a slight reduction in prostate cancer mortality but also a concomitant overdiagnosis of low-risk tumors. Prostate-specific antigen levels are affected by use of cholesterol-lowering statin drugs, but the association of statin use with PSA screening performance is unknown.

Objective

To investigate whether statin use was associated with outcomes of a randomized PSA-based prostate cancer screening intervention.

Design, Setting, and Participants

This post hoc subgroup analysis of a cohort from a population-based randomized clinical trial used data from the population-based Finnish Randomized Study of Prostate Cancer Screening, which randomized men to PSA screening or routine care from March 1, 1996, to December 31, 1999, with follow-up continuing until December 31, 2015. The population included all men aged 55 to 67 years at baseline and residing in the Tampere or Helsinki districts of Finland. Information on statin purchases from 1996 to 2009 was obtained from a national prescription registry. Eligible men were identified from the population registry of Finland. Prevalent prostate cancer cases at baseline were excluded. Data were analyzed from January 1, 2019 to March 31, 2021.

Interventions

Three invitations for PSA screening at 4-year intervals from 1996 to 2007 vs routine care.

Main Outcomes and Measures

Risk for prostate cancer overall, high-risk disease, and prostate cancer mortality in the screening group vs the control group as an intention-to-treat analysis. The analysis was stratified by statin use.

Results

The study comprised 78 606 men (median age, 59 years [range, 55-67 years]) with statin purchase data available. Although PSA screening was associated with increased prostate cancer incidence among statin nonusers (screening vs control, 11.2 vs 8.6 per 1000 person-years); rate ratio [RR], 1.31; 95% CI, 1.24-1.38), no similar increase in incidence was observed among statin users (6.9 vs 5.9 per 1000 person-years; RR, 1.02; 95% CI, 0.95-1.10; P < .001 for interaction). Incidence of low-risk (Gleason score 6) and localized tumors was lower among statin users, whereas detection of tumors with a Gleason score of 8 to 10 was similar. Screening was associated with a lower incidence of metastatic tumors regardless of statin use.

Conclusion and Relevance

In this post hoc subgroup analysis of a cohort from a population-based randomized clinical trial, PSA screening among statin users was associated with a decreased incidence of advanced prostate cancer that was similar among statin nonusers, but with less increase in detection of low-grade localized tumors in statin users than in nonusers. These findings suggest that statin use does not materially compromise benefits of PSA-based screening.

Number of screening rounds attended and incidence of high-risk prostate cancer in the Finnish Randomized Study of Screening for Prostate Cancer (FinRSPC)

BACKGROUND

The European Randomized Study of Screening for Prostate Cancer has shown a 20% reduction in prostate cancer (PC) mortality by prostate-specific antigen-based screening. In addition, screening has been shown to reduce the risk of advanced PC. The objective of the current study was to analyze the impact of screening participation on the incidence of PC by risk group.

METHODS

The participants in the screening arm of the Finnish trial (31,867 men) were classified according to screening attendance in a time-dependent fashion. Initially, all men in the screening arm were regarded as nonattenders until the first screening attendance; they then remained in the once-screened group until the second screen and similarly for the possible third round. The control arm formed the reference group. Follow-up started at randomization and ended at the time of diagnosis of PC, emigration, or the end of 2015. PC cases were divided into risk groups according to European Association of Urology definitions.

RESULTS

The incidence of low-risk PC increased with the number of screens, whereas no clear relation with participation was noted in the intermediate-risk and high-risk cases. For patients with advanced PC, attending screening at least twice was associated with a lower risk.

CONCLUSIONS

Screening reduces the risk of advanced PC after only 2 screening cycles. A single screen demonstrated no benefit in terms of PC incidence. Repeated screening is necessary to achieve screening advantages.

Personalized strategies in population screening for prostate cancer

This review discusses evidence for population-based screening with contemporary screening tools. In Europe, prostate-specific antigen (PSA)-based screening led to a relative reduction of prostate cancer (PCa) mortality, but also to a substantial amount of overdiagnosis and unnecessarily biopsies. Risk stratification based on a single variable (a clinical variable or based on the presence of a lesion on prostate imaging) or based on multivariable approaches can aid in reducing unnecessary prostate biopsies and overdiagnosis by selecting men who can benefit from further clinical assessment. Multivariable approaches include clinical variables, and biomarkers, often combined in risk calculators or nomograms. These risk calculators can also incorporate the result of MRI imaging. In general, as compared to a purely PSA based approach, the combination of relevant prebiopsy information results in superior selection of men at higher risk of harboring clinically significant prostate cancer. Currently, it is not possible to draw any conclusions on the superiority of these multivariable risk-based approaches since head-to-head comparisons are virtually lacking. Recently initiated large population-based screening studies in Finland, Germany and Sweden, incorporating various multivariable risk stratification approaches will hopefully give more insight in whether the harm-benefit ratio can be improved, that is, maintain (or improving) the ability to reduce metastatic disease and prostate cancer mortality while reducing harm caused by unnecessary testing and overdiagnosis including related overtreatment.