Long-term Results of Active Surveillance in the Göteborg Randomized, Population-based Prostate Cancer Screening Trial.

BACKGROUND

Active surveillance (AS) has become a well-accepted and widely used treatment strategy.

OBJECTIVE

To assess the long-term safety of AS for men with screen-detected prostate cancer (PCa).

DESIGN, SETTING, AND PARTICIPANTS: All men with screen-detected PCa who had very low-, low-, or intermediate-risk PCa and were managed with AS (January 1, 1995 to December 31, 2014) in the Göteborg screening trial.

INTERVENTION

Prostate-specific antigen tests every 3-12 mo, rebiopsies in cases of clinical progression, and every 2-3 yr in men with stable disease. Triggers for intervention were disease progression (prostate-specific antigen, grade, and/or stage) or patient initiative.

OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS

Treatment-free, failure-free, PCa-specific, and overall survival. The Kaplan-Meier method and Cox proportional hazards models were used.

RESULTS AND LIMITATIONS

Four-hundred and seventy-four men were managed with AS (median age at diagnosis 66.0 yr, median follow-up 8.0 yr). Two-hundred and two men discontinued AS and initiated treatment. The 10-yr and 15-yr treatment-free survival was 47% and 34%, respectively. The hazard ratio for the treatment for low- and intermediate-risk PCa, compared with very low risk, was 1.4 (95% confidence interval [CI] 1.01-1.94) and 1.6 (95% CI 1.13-2.25). Fifty-four men failed AS. The 10-yr and 15-year failure-free survival was 87% and 72%, respectively. These estimates were 94% and 88% for the very low-risk group, 85% and 77% for the low-risk group, and 73% and 40% for the intermediate-risk group. The hazard ratio for failure for low- and intermediate-risk PCa, compared with very low-risk, was 2.2 (95% CI 1.05-4.47) and 4.8 (95% CI 2.44-9.33). Six men died from PCa and none had very low-risk PCa. The 10-yr and 15-yr PCa-specific survival was 99.5% and 96%, respectively. These estimates were 100% for the very low-risk group, 100% and 94% for the low-risk group, and 98% and 90% for the intermediate-risk group. No predefined protocol was used.

CONCLUSIONS

AS is safe for men with very low-risk PCa, but for men with low- and intermediate-risk PCa, AS carries a risk of missing the possibility of being able to cure the cancer. It is questionable whether men who are not in the lowest tumor risk group and who have a long remaining life expectancy are suitable candidates for this strategy.

PATIENT SUMMARY

Long-term results from this study indicate that some men will miss their chance of cure with active surveillance and it is questionable whether active surveillance is a suitable strategy for men who are not in the lowest tumor risk group and who have a very long remaining life expectancy.