An examination of the dynamic changes in prostate-specific antigen occurring in a population-based cohort of men over time

Variation of Prostate-specific Antigen Value in Men and Risk of High-grade Prostate Cancer: Analysis of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Study

OBJECTIVE

To investigate variations in prostate-specific antigen (PSA) levels among men with an initial normal PSA level in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial study.

METHODS

Data were extracted from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial study data set on all men in the interventional arm, with 2 tests performed in a period of < 2 years and with an initial result of the first test <4 ng/mL. The range of variation between first and second tests was computed. Risks of cancer stratified on Gleason score were computed using logistic regression.

RESULTS

A total of 31,286 men had 2 PSA tests within 2 years and with an initial value < 4 ng/mL. From the first to the second test, the median variation of PSA levels was 3.4% (interquartile range, -15% to +26%). The variation in PSA value was not associated with the delay between the first and the second test (P = .36), age (P = .16), body mass index (P = .41), and race (P = .12). A total of 2,781 prostate cancers were diagnosed during follow-up. Adjusting for age and initial PSA level, the risk of prostate cancer increased linearly with increasing PSA level at the second test, with an odds ratio of 1.079 (95% confidence interval, 1.058-1.101) for each percent increase in PSA level. However, the variation in PSA was not associated with a higher Gleason score (P = .95 for level variations in cancer of Gleason score < 7 vs ≥ 7).

CONCLUSION

Although an increase in PSA level over time is associated with increased risk of prostate cancer, this association is not related to more aggressive tumors.

Management of men with a suspicion of prostate cancer after negative initial prostate biopsy results

INTRODUCTION

For men with elevated prostate-specific antigen (PSA), appropriate management after negative prostate biopsy remains controversial. After determining PSA kinetics, subsequent follow-up was considered.

PATIENTS AND METHODS

A total of 115 cases with negative repeat biopsy were followed by evaluating PSA kinetics and ratio of percent free PSA (F/T) and by performing second repeat biopsy.

RESULTS

Eighteen cancer cases were diagnosed. Shorter PSA doubling times and faster velocities were found in cancer cases compared with cases without cancer. We observed a clear decrease in F/T among cancer cases.

CONCLUSIONS

To avoid unnecessary repeat biopsies, cases with a suspicion of cancer after negative biopsy can be divided into two groups: one that requires additional biopsies and one with an average change in PSA of <1 ng/ml/year and no change in F/T, which is recommended for surveillance as stable disease without biopsy over a specified time period.

Long-term prostate-specific antigen velocity in improved classification of prostate cancer risk and mortality

BACKGROUND

It remains unclear whether adding long-term prostate-specific antigen velocity (PSAV) to baseline PSA values improves classification of prostate cancer (PCa) risk and mortality in the general population.

OBJECTIVE

To determine whether long-term PSAV improves classification of PCa risk and mortality in the general population.

DESIGN, SETTING, AND PARTICIPANTS

We studied 503 men aged 30-80 yr, with and without PCa, who had repeated PSA measurements over 20 yr and up to 28 yr before PCa diagnosis. These were selected from among 7455 men in the Copenhagen City Heart Study, a prospective, general population study with follow-up from 1981 through 2010. Results were subsequently applied to all 1 351 441 men aged 40-80 yr living in Denmark from 1997 through 2006.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

PCa risk and mortality were assessed using Cox regression. Improvement in risk classification was assessed using the net reclassification index (NRI).

RESULTS

Age-adjusted hazard ratios for PCa risk and mortality were 2.7-5.3 and 2.3-3.4, respectively, for long-term PSAV when added to models already including baseline PSA values. For PCa risk and mortality, adding long-term PSAV to models already including baseline PSA values and age yielded continuous NRIs of 98-99% and 56-106%, respectively. Used on a nationwide scale (eg, for men aged 60-64 yr), long-term PSAV >0.35 versus ≤ 0.35 ng/ml per year appropriately reclassified 128 of 10 000 men with PCa and 8095 of 10 000 men with no PCa. Correspondingly, inappropriately reclassified were 49 of 10 000 men with PCa and 1658 of 10 000 men with no PCa.

CONCLUSIONS

Long-term PSAV in addition to baseline PSA value improves classification of PCa risk and mortality. Applying long-term PSAV nationwide, the ratio of appropriately to inappropriately classified men would typically be 5:1.