Six-core versus twelve-core prostate biopsy: a retrospective study comparing accuracy, oncological outcomes and safety.

AIMS: To compare sextant and 12 core transrectal ultrasound-guided (TRUS) prostate biopsies for detecting prostate cancer (PCa) and to determine whether 12-core prostate biopsies are associated with a higher incidence of insignificant prostate cancer and complications.

METHODS: A retrospective study was performed on all patients with a positive TRUS biopsy for prostate cancer between January 2011 and December 2013. Group A underwent a sextant core prostate biopsy and group B underwent a 12-core prostate biopsy. Outcome variables were cancer detection rates, oncological outcomes, incidence of clinically insignificant PCa and incidence of biopsy associated complications. Exclusion criteria included a negative TRUS biopsy and metastatic prostate cancer.

RESULT: In total 718 prostate biopsies were performed and 286 patients met inclusion criteria (143 patients in each group). The overall cancer detection rate was 43 % in group A compared to 53 % in group B (p = 0.03). In group A, 31 (21.7 %) patients proceeded to open retropubic radical prostatectomy (RRP) compared to 36 (25.2 %) in group B (p = 0.7). Sextant biopsies were associated with a significantly higher rate of upgrading compared to 12-core biopsies in RRP specimens (51.6 versus 25 % respectively, p < 0.01). The incidence of clinically insignificant PCa was 10.5 % in group A versus 14.7 % in group B (p = 0.2). The incidence of urosepsis post biopsy was 0.7 % in both groups (n = 1).

CONCLUSION: Twelve-core biopsies were associated with higher PCa cancer detection rates, greater accuracy for Gleason grading and no differences for detecting clinically insignificant PCa or urosepsis compared to sextant biopsies.