Significance of Core Length in Current Transrectal Ultrasound-guided Prostate Biopsy in Patients with Normal Digital Rectal Examination

Objective: To reveal the significance of core length in current primary transrectal ultrasound-guided prostate biopsy (TRUS-PB) in patients with normal digital rectal examination. Materials and Methods: Data of 3520 patients, who received TRUS-PB between March 2002 and April 2015, were reviewed retrospectively. A total of 1627 primary biopsy patients with a normal digital examination and with no lesion in TRUS were included in the study. The mean core length was found by dividing the sum of the total core lengths by the core number. The relationships of cancer detection rate (CDR) with age, Prostate-specific antigen (PSA) value, prostate volume, number of cores (10 or 12 cores) and mean core length were investigated. Results: The mean patient age, PSA and prostate volume were 62.3 +/- 7.9 years, 9.1 +/- 7.8 ng/mL and 55.8 +/- 21 mL, respectively. Cancer was diagnosed in 394 patients (24.2%). The mean core length was 12.7 +/- 1.7 (4.3-21.5) mm. Ten- and 12- core biopsies were performed in 1068 (65.6%), and 559 (34.4 0 10) patients, respectively. Older age, PSA, mean core length, number of cores and reduced prostate volume were found to be associated with CDR (p<0.001, p<0.001, p=0.006 p=0.043, and p<0.001, respectively). In the multivariate analysis, age, PSA, prostate volume, mean core length, and number of cores were found to be independent factors in CDR (p<0.001, p<0.001, p<0.001, p=0.006 and p=0.009, respectively). Conclusion: Age, PSA, prostate volume, and number of cores, together with core length, are independent risk factors for cancer detection in TRUSPB.