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BACKGROUND There is a body of evidence indicating that aspirin may reduce the risk of cancer mortality. However, to the authors' knowledge, the optimal exposure timing and mechanism of action remain unclear. In the current study, the authors investigated associations between prediagnostic aspirin use and breast cancer-specific mortality in a US population. METHODS Postmenopausal women diagnosed with stage I to III breast cancer (1993-2009) were identified (2925 women with a total of 18,073 person-years) from the National Cancer Institute's Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Prediagnostic aspirin use (1274 women) was identified from study questionnaires. Multivariate Cox proportional hazards models were used to estimate hazard ratios (HRs) with 95% confidence intervals (95% CIs) for associations between aspirin use and breast cancer-specific mortality. Effect modification by lymph node status was evaluated. RESULTS Prediagnostic aspirin use was not found to be associated with lower breast cancer-specific mortality (HR, 0.95; 95% CI, 0.68-1.31 [P = .74]). In analyses stratified by lymph node status, aspirin use was found to be associated with lower breast cancer-specific mortality among women with lymph node-negative tumors (HR, 0.54; 95% CI, 0.32-0.93 [P = 0.02]), but not those with lymph node-positive tumors (HR, 1.41; 95% CI, 0.92-2.16 [P = 0.11]). Tests for interaction were found to be statistically significant (P for interaction =.006). No association was noted between aspirin use and lymph node status. CONCLUSIONS Prediagnostic aspirin use was not found to be associated with a reduction in breast cancer-specific mortality overall. However, effect modification by lymph node status was observed and mortality was found to be reduced by approximately one-half among aspirin users with lymph node-negative disease. This represents a clinically significant reduction in breast cancer mortality. These findings contribute to the understanding of aspirin's mechanism of action in breast cancer. However, further etiologic research to understand this association is warranted. Cancer 2016. © 2016 American Cancer Society.

BACKGROUND Follow-through of a positive screening test is necessary to reap the potential benefits of cancer screening. Racial variation in follow-through diagnostic care may underlie a proportion of the known disparity in prostate cancer mortality. The authors used data from the screening arm of the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial to determine whether race is associated with the use of follow-up diagnostic testing after a positive initial screening evaluation. METHODS Men who had a prostate-specific antigen (PSA) level >4 ng/mL at any time during the study were included. The proportion of men who underwent follow-up evaluation with a repeat PSA, a prostate biopsy, or either test within 9 months was determined, and the authors tested for differences in follow-through according to race using mixed-effects multivariate models with a random effect for accrual site to account for clustering. Models were stratified according to age (

Background Two large-scale prostate cancer screening trials using prostate-specific antigen (PSA) have given conflicting results in terms of the efficacy of such screening. One of those trials, the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, previously reported outcomes with 13 years of follow-up. This study presents updated findings from the PLCO trial. Methods The PLCO trial randomized subjects from 1993 to 2001 to an intervention or control arm. Intervention-arm men received annual PSA tests for 6 years and digital rectal examinations for 4 years. This study used a linkage with the National Death Index to extend mortality follow-up to a maximum of 19 years after randomization. Results Men were randomized to the intervention arm (n = 38,340) or the control arm (n = 38,343). The median follow-up time was 14.8 years (25th/75th, 12.7/16.5 years) in the intervention arm and 14.7 years (25th/75th, 12.6/16.4 years) in the control arm. There were 255 deaths from prostate cancer in the intervention arm and 244 deaths from prostate cancer in the control arm; this meant a rate ratio (RR) of 1.04 (95% confidence interval [CI], 0.87-1.24). The RR for all-cause mortality was 0.977 (95% CI, 0.950-1.004). It was estimated that 86% of the men in the control arm and 99% of the men in the intervention arm received any PSA testing during the trial, and the estimated yearly screening-phase PSA testing rates were 46% and 84%, respectively. Conclusions Extended follow-up of the PLCO trial over a median of 15 years continues to indicate no reduction in prostate cancer mortality for the intervention arm versus the control arm. Because of the high rate of control-arm PSA testing, this finding can be viewed as showing no benefit of organized screening versus opportunistic screening. Cancer 2017;123:592-599. © 2016 American Cancer Society.

BACKGROUND. Two recent chemoprevention trials demonstrated significant reductions in overall prostate cancer incidence. However, a possible increase in high-grade disease has raised concerns that the harms of the drugs, including mortality because of high-grade disease, may outweigh the benefits. The authors attempted to estimate the effect of these drugs on prostate cancer mortality to be able to better evaluate the cost-benefit tradeoff. METHODS. The authors analyzed prostate cancer incidence in the Prostate Cancer Prevention Trial (PCPT) and Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial, which evaluated finasteride and the related compound dutasteride, respectively (both vs placebo). They used 13-year prostate cancer survival data from the Prostate, Lung, Colorectal and Ovarian (PLCO) trial to project prostate cancer mortality from incidence patterns; survival rates were applied to incident cancers according to prognostic strata, which were defined by Gleason score, prostate-specific antigen level, and clinical stage. For PCPT, the analysis was performed using both original trial results and previously published adjusted analyses that attempted to account for artifacts related to the drugs' effect on prostate volume. RESULTS. For the PCPT trial, the estimated relative risk (RR) for prostate cancer mortality was 1.02 (95% confidence interval [95% CI], 0.85-1.23) using the original trial results and 0.87 (95% CI, 0.72-1.06) and 0.91 (95% CI, 0.76-1.09) based on the adjusted PCPT analyses. For the REDUCE trial, the RR for prostate cancer mortality was 0.93 (95% CI, 0.80-1.08). CONCLUSIONS. Projecting a mortality outcome of the PCPT and REDUCE trials as an approach to weighing benefits versus harms suggests at most a small increase in prostate cancer mortality in the treatment arms, and possibly a modest decrease. Cancer 2013. © 2012 American Cancer Society.

There is a body of evidence indicating that aspirin may reduce the risk of cancer mortality. However, to the authors' knowledge, the optimal exposure timing and mechanism of action remain unclear. In the current study, the authors investigated associations between prediagnostic aspirin use and breast cancer-specific mortality in a US population.Postmenopausal women diagnosed with stage I to III breast cancer (1993-2009) were identified (2925 women with a total of 18,073 person-years) from the National Cancer Institute's Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Prediagnostic aspirin use (1274 women) was identified from study questionnaires. Multivariate Cox proportional hazards models were used to estimate hazard ratios (HRs) with 95% confidence intervals (95% CIs) for associations between aspirin use and breast cancer-specific mortality. Effect modification by lymph node status was evaluated.Prediagnostic aspirin use was not found to be associated with lower breast cancer-specific mortality (HR, 0.95; 95% CI, 0.68-1.31 [P = .74]). In analyses stratified by lymph node status, aspirin use was found to be associated with lower breast cancer-specific mortality among women with lymph node-negative tumors (HR, 0.54; 95% CI, 0.32-0.93 [P = 0.02]), but not those with lymph node-positive tumors (HR, 1.41; 95% CI, 0.92-2.16 [P = 0.11]). Tests for interaction were found to be statistically significant (P for interaction =.006). No association was noted between aspirin use and lymph node status.Prediagnostic aspirin use was not found to be associated with a reduction in breast cancer-specific mortality overall. However, effect modification by lymph node status was observed and mortality was found to be reduced by approximately one-half among aspirin users with lymph node-negative disease. This represents a clinically significant reduction in breast cancer mortality. These findings contribute to the understanding of aspirin's mechanism of action in breast cancer. However, further etiologic research to understand this association is warranted. Cancer 2016;122:2067-75. © 2016 American Cancer Society.

Follow-through of a positive screening test is necessary to reap the potential benefits of cancer screening. Racial variation in follow-through diagnostic care may underlie a proportion of the known disparity in prostate cancer mortality. The authors used data from the screening arm of the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial to determine whether race is associated with the use of follow-up diagnostic testing after a positive initial screening evaluation.Men who had a prostate-specific antigen (PSA) level4 ng/mL at any time during the study were included. The proportion of men who underwent follow-up evaluation with a repeat PSA, a prostate biopsy, or either test within 9 months was determined, and the authors tested for differences in follow-through according to race using mixed-effects multivariate models with a random effect for accrual site to account for clustering. Models were stratified according to age (65 years and ≥65 years).Among 6294 men who had a PSA elevation during the study period, 70% underwent a repeat PSA or prostate biopsy within 9 months. Non-Hispanic black men aged65 years had 45% lower odds of undergoing a repeat PSA test or prostate biopsy compared with non-Hispanic white men (odds ratio, 0.55; 95% confidence interval, 0.37-0.82), whereas there was no racial difference in follow-through among older men.The current results suggest that limitations in access to care among non-Hispanic black men under the age of Medicare eligibility may underlie the paradoxically low use of follow-through diagnostic care among non-Hispanic black men in the United States.

Two recent chemoprevention trials demonstrated significant reductions in overall prostate cancer incidence. However, a possible increase in high-grade disease has raised concerns that the harms of the drugs, including mortality because of high-grade disease, may outweigh the benefits. The authors attempted to estimate the effect of these drugs on prostate cancer mortality to be able to better evaluate the cost-benefit tradeoff.The authors analyzed prostate cancer incidence in the Prostate Cancer Prevention Trial (PCPT) and Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial, which evaluated finasteride and the related compound dutasteride, respectively (both vs placebo). They used 13-year prostate cancer survival data from the Prostate, Lung, Colorectal and Ovarian (PLCO) trial to project prostate cancer mortality from incidence patterns; survival rates were applied to incident cancers according to prognostic strata, which were defined by Gleason score, prostate-specific antigen level, and clinical stage. For PCPT, the analysis was performed using both original trial results and previously published adjusted analyses that attempted to account for artifacts related to the drugs' effect on prostate volume.For the PCPT trial, the estimated relative risk (RR) for prostate cancer mortality was 1.02 (95% confidence interval [95% CI], 0.85-1.23) using the original trial results and 0.87 (95% CI, 0.72-1.06) and 0.91 (95% CI, 0.76-1.09) based on the adjusted PCPT analyses. For the REDUCE trial, the RR for prostate cancer mortality was 0.93 (95% CI, 0.80-1.08).Projecting a mortality outcome of the PCPT and REDUCE trials as an approach to weighing benefits versus harms suggests at most a small increase in prostate cancer mortality in the treatment arms, and possibly a modest decrease.

BACKGROUND: Because of its relatively low incidence, bladder cancer screening might have a better ratio of benefits to harms if it is restricted to a high-risk population. Data from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial were used and simple decision analytic techniques were applied to compare different eligibility criteria for a screening trial. METHODS: For a variety of possible eligibility criteria, the percentage of the population aged 55 years to 74 years and classified as being at high risk for developing invasive or high-grade carcinoma, and therefore likely to benefit from screening, was calculated. Regression models were used to calculate a risk score based on age, sex, smoking history, and family history of bladder cancer. The reduction in cases was calculated given hypothetical risk reductions associated with screening. The trade-off between patients screened and tumors avoided was calculated as a net benefit. RESULTS: The 5-year probability of being diagnosed with invasive bladder cancer was 0.24%. Using a risk score > 6 or > 8 as the eligibility criterion for a trial was generally superior to including all older adults. In a typical scenario, a risk score > 6 would result in approximately 25% of the population being screened to prevent 57 invasive or high-grade bladder cancers per 100,000 population; screening the entire population would prevent only an additional 38 cases. CONCLUSIONS: Screening for bladder cancer can be optimized by restricting it to a subgroup of patients considered to be at elevated risk. Different eligibility criteria for a screening trial can be compared rationally using decision-analytic techniques. Cancer 2013. © 2012 American Cancer Society.