Increasing prostate-specific antigen levels differently influence prostate cancer detection rates of two different 12-core prostate biopsy schemes.

Objective: To compare two 12-core transrectal ultrasound-guided prostate biopsy schemes in respect to cancer detection rates.

Methods: Retrospective, single-center analysis of consecutive patients (n = 897) who underwent prostate biopsy (S1) with all 12 cores from far lateral areas (n = 269) or prostate biopsy (S2) with 6 cores from parasagittal and 6 from far lateral areas (n = 628).

Results: Crude cancer detection rates with S1 and S2 were similar (39.0 and 38.9% for the first biopsy and 29.4 and 31.3% for repeated biopsies, respectively). Abnormal digital rectal exam, lower prostate volume and higher prostate-specific antigen (PSA) levels were independently associated with higher odds of cancer detection. Regarding first biopsies (n = 747), there was significant interaction between biopsy scheme and PSA (p < 0.001). Overall, the adjusted odds of cancer detection were higher with S1 (S1/S2 odds ratio = 2.54, 95% CI: 1.12-5.74), but the S1-S2 relationship was conditional on PSA: odds ratios progressively increased with increasing PSA from 0.64 (95% CI: 0.40-1.02) at PSA 5 ng/ml to 39.1 (95% CI: 2.71-566) at 75 ng/ml.

Conclusion: Higher PSA levels increase the probability of cancer detection with 12-core prostate biopsies, but relative efficiency of different procedures appeared conditional on the PSA level. Data suggest that PSA levels should be considered in the choice of prostate biopsy sampling scheme.