Screening: should more biopsies be taken in larger prostates?

Abstract

Objective: To assess the number of missed prostate cancers and the frequency of aggressive disease when taking lateralized sextant prostate biopsies, irrespective of the total prostate volume (Pvol), during screening for prostate cancer.

Subjects and methods: Men participating in the European Randomized Study of Screening for Prostate Cancer, Rotterdam section, aged 55-74 years, with a prostate-specific antigen (PSA) level of ≥3.0 ng/mL, and a negative sextant biopsy result at the initial screening round, were followed for 8 years. Cases of prostate cancer detected during the follow-up by screening, or detected clinically as interval cancers, were assessed. Pvol at the initial screening round was related to the number of cancers found during the follow-up. Furthermore, the frequency of aggressive cancer (N1 or M1, PSA >20 ng/mL, Gleason >7) was evaluated using multivariate logistic regression analysis, including age, PSA level and Pvol.

Results: In the total of 1305 men, 152 prostate cancers were detected during 8 years of follow-up (11.6%); 23 were classified as aggressive (15.1%), and 50 (32.9%) were detected as interval cancers. There was a significant relation between a larger Pvol at the initial screening round and fewer cancers (odds ratio 0.1, P < 0.001). In multivariate logistic regression, the initial PSA level (odds ratio 3.21, 95% confidence interval, CI 1.2-8.3) and smaller Pvol (0.08, 95% CI 0.03-0.26) were statistically significant predictors for all cancers and aggressive cancers (PSA odds ratio 70.37, 95% CI 13.5-366.2; Pvol odds ratio 0.03, 95% CI 0.01-0.35).

Conclusions: Men with a smaller Pvol and an initially high PSA level were at greater risk of cancer detection and of an aggressive cancer during the follow-up. The use in clinical practice of volume-adjusted biopsy schemes should not be implemented automatically in screening programmes with repeated screening.