The Association Between Age, Prostate Cancer Risk, and Higher Gleason Score in a Long-term Screening Program: Results from the Göteborg-1 Prostate Cancer Screening Trial.

BACKGROUND

Studies have suggested associations between greater age, increased risk of prostate cancer (PC), and higher Gleason score.

OBJECTIVE

The present study aimed at investigating these associations within the Göteborg-1 randomized, population-based PC screening trial.

DESIGN, SETTING, AND PARTICIPANTS: The screening arm of the Göteborg-1 screening trial comprises 10000 randomly selected men (aged 50-64 yr at randomization) from the Göteborg region of Sweden. Between 1995 and 2014, they were biennially invited to prostate-specific antigen (PSA) testing to an upper age limit of 70 yr (range 67-71 yr). PSA ≥3 ng/ml triggered a prostate biopsy (sextant biopsy 1995-2009, thereafter a ten-core biopsy).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The impact of age on Gleason score, given a screen-detected PC, was investigated with multinomial logistic regression analyses adjusted for year of testing and screening round.

RESULTS AND LIMITATIONS

Overall, 7625 men had at least one PSA test and 1022 men were diagnosed with PC. For men with screen-detected PC, age was associated with the risk of clinically significant PC above and beyond screening round and year of testing (p < 0.001). For each 1-yr increase in age, the risk of being diagnosed with a Gleason score ≥3 + 4 cancer (vs <7) increased by 11% (95% confidence interval [CI] 4.7-17), whereas the risk of being diagnosed with a Gleason score ≥4 + 3 cancer (vs <7) increased by 8.5% (95% CI -1.6 to 20).

CONCLUSIONS

The increased risk of a higher Gleason score in older men should be considered when counseling men regarding early diagnosis and treatment for PC.

PATIENT SUMMARY

We found that older age increased both the risk of prostate cancer and the risk of more aggressive prostate cancer.