Screening asymptomatic men for prostate cancer: A comparison of international guidelines on prostate-specific antigen testing

Prostate Cancer Foundation Screening Guidelines for Black Men in the United States

BACKGROUND

In the United States, Black men are at highest risk for being diagnosed with and dying from prostate cancer. Given this disparity, we examined relevant data to establish clinical prostate-specific antigen (PSA) screening guidelines for Black men in the United States.

METHODS

A comprehensive literature search identified 1848 unique publications for screening. Of those screened, 287 studies were selected for full-text review, and 264 were considered relevant and form the basis for these guidelines. The numbers were reported according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines.

RESULTS

Three randomized controlled trials provided Level 1 evidence that regular PSA screening of men 50 to 74 years of age of average risk reduced metastasis and prostate cancer death at 16 to 22 years of follow-up. The best available evidence specifically for Black men comes from observational and modeling studies that consider age to obtain a baseline PSA, frequency of testing, and age when screening should end. Cohort studies suggest that discussions about baseline PSA testing between Black men and their clinicians should begin in the early 40s, and data from modeling studies indicate prostate cancer develops 3 to 9 years earlier in Black men compared with non-Black men. Lowering the age for baseline PSA testing to 40 to 45 years of age from 50 to 55 years of age, followed by regular screening until 70 years of age (informed by PSA values and health factors), could reduce prostate cancer mortality in Black men (approximately 30% relative risk reduction) without substantially increasing overdiagnosis.

CONCLUSIONS

These guidelines recommend that Black men should obtain information about PSA screening for prostate cancer. Among Black men who elect screening, baseline PSA testing should occur between ages 40 and 45. Depending on PSA value and health status, annual screening should be strongly considered. (Supported by the Prostate Cancer Foundation.).

Designing a Simple Electrochemical Genosensor for the Detection of Urinary PCA3, a Prostate Cancer Biomarker

This study investigates the feasibility of a simple electrochemical detection of Prostate Cancer Antigen 3 (PCA3) fragments extracted from patients' urine, using a thiolated single-strand DNA probe immobilized on a gold surface without using a redox probe. To enhance the PCA3 recognition process, we conducted a comparative analysis of the hybridization location using two thiolated DNA probes: Probe 1 targets the first 40 bases, while Probe 2 targets the fragment from bases 47 to 86. Hybridization with PCA3 followed, using square wave voltammetry. The limit of detection of the designed genosenors were of the order of (2.2 ng/mL), and (1.6 ng/mL) for Probes 1 and 2, respectively, and the subsequent sensitivities were of the order of (0.09 ± 0.01) µA-1 · µg-1 · mL and (0.10 ± 0.01) µA-1 · µg-1 · mL. Specificity tests were then conducted with the sensor functionalized with Probe 2, as it presents better analytical performances. The electrochemical results indicate that the designed sensor can clearly discriminate a complementary target from a non-complementary one. A further modeling of the calibration curves with the Power Law/Hill model indicates that the dissociation constant increases by one order of magnitude, confirming the ability of the designed sensor to perfectly discriminate complementary targets from non-complementary ones.

Spatial patterns of prostate-specific antigen testing in asymptomatic men across Australia: a population-based cohort study, 2017-2018

OBJECTIVES

In Australia, while prostate-specific antigen (PSA) testing rates vary by broad area-based categories of remoteness and socio-economic status, little is known about the extent of variation within them. This study aims to describe the small-area variation in PSA testing across Australia.

STUDY DESIGN

This was a retrospective population-based cohort study.

METHODS

We received data for PSA testing from the Australian Medicare Benefits Schedule. The cohort included men (n = 925,079) aged 50-79 years who had at least one PSA test during 2017-2018. A probability-based concordance was applied across multiple iterations (n = 50) to map each postcode to small areas (Statistical Areas 2; n = 2,129). For each iteration, a Bayesian spatial Leroux model was used to generate smoothed indirectly standardized incidence ratios across each small area, with estimates combined using model averaging.

RESULTS

About a quarter (26%) of the male population aged 50-79 years had a PSA test during 2017-2018. Testing rates among small areas varied 20-fold. Rates were higher (exceedance probability>0.8) compared with the Australian average in the majority of small areas in southern Victoria and South Australia, south-west Queensland, and some coastal regions of Western Australia but lower (exceedance probability<0.2) in Tasmania and Northern Territory.

CONCLUSIONS

The substantial geographical variation in PSA testing rates across small areas of Australia may be influenced by differences in access to and guidance provided by clinicians and attitudes and preferences of men. Greater understanding of PSA testing patterns by subregions and how these patterns relate to health outcomes could inform evidence-based approaches to identifying and managing prostate cancer risk.

Two conflicting guidelines on prostate specific antigen screening in Japan

Japanese urologists need to listen seriously to the opinions of public health physicians and it is necessary to properly inform people of prostate specific antigen screening.