Are IPCa Really Insignificant in Korean Men? Epstein criteria were applied to IPCa patients in Asia than in any other country.6,7 Our aim was to determine whether 12 core-extended biopsies of the prostate could reliably predict IPCa in men who were candidates for watchful waiting. Our aim was also to determine trends in the inci- dence of IPCa after prostate biopsies and pathology up- grade after radical prostatectomy. MATERIALS AND METHODS Overview Two hundred and ninety-seven patients who had undergone a radical prostatectomy after 12-core transrectal ultrasonog- raphy-guided prostatic biopsies between January 2004 and December 2009 at our institution were enrolled for a retro- spective analysis. Before initiating this study, we obtained approval from the institutional review board. We reviewed the specimens from prostatic biopsies and radical prostatec- tomies that had been performed in 2004 through to 2005 (group 1), 2006 through to 2007 (group 2), and 2008 through to 2009 (group 3). According to the Epstein crite- ria, IPCa was defined as a PSA density of less than 0.15 ng/ dL, a biopsy Gleason score ≤6, less than or equql to 2 posi- tive cores in 6 core biopsies, and a single core percentage under 50%.4,8 We excluded patients who had undergone prostate biopsy at other institution, hormone therapy or radi- ation therapy before the radical prostatectomy. The radical prostatectomy was performed by a single surgeon (B.H.C.). Biopsy protocol A kit from BK Medical, Denmark was used for prostatic bi- opsies (right 6 cores and left 6 cores). The 12-core biopsies were done in each patient by a urologist with 12 years of experience. According to the standard of previous biopsy protocol, sextant biopsy was performed from the apex, mid, and base of the right and left parasagittal planes of the pros- tate including an additional 3 cores from the peripheral zone positioned more laterally on each side.8 Biopsy was per- formed either under local anesthesia or general anesthesia and 12 cores were obtained regardless of prostate volume. In cases under anesthesia, patients required a 3-5 day ad- ministration of fluoroquinolone and midnight NPO from the day before biopsy was performed, usually followed by a 3-5 day course of antibiotic treatment. The standard length of the biopsy cores was 15 mm, and each core was embed- ded separately. They were divided in multiple containers, and designated as either right or left standard sextant or lat- eral peripheral zone biopsy cores.9 Pathology The pathologic grading was done according to the Gleason scoring system, and the pathologic review was performed by a single experienced urologic pathologist (S.W.H.). The prostatectomy specimens were fixed overnight (10% neutral buffered formaldehyde) and coated with India ink. Trans- verse whole mount step section specimens were obtained at 4 mm intervals on a plane. The presence and extent of can- cer were outlined on the glass cover. The presence of tumor cells beyond the capsular margin was defined as extracapsu- lar extension. The largest tumor nodule was mapped and categorized according to grade, location, volume, pathologic stage and margin status. The volume was calculated using a computer assisted image analysis system.10 Statistics Statistical analyses were performed using Student’s t-test to evaluate the demographic and clinical differences between IPCa and significant PCa groups. Multivariate analysis was performed to determine the independent prognostic factors for IPCa. A chi-square test was used to compare groups for categorical variables, and a p value of <0.05 was consid- ered significant. RESULTS Of the 297 cases, 38 (12.8%) were found to be IPCa. The average age was 65.2 years, average serum PSA was 5.49 ng/dL, and average PSA density was 0.11. Table 1 shows the differences in preoperative clinical variables between the IPCa and significant PCa groups. The mean PSA and PSA density were 5.49 ng/mL and 0.11 in the IPCa group and 9.91 ng/mL and 0.42 in the significant PCa group (p=0.012, 0.027, respectively). After a radical prostatectomy, an up- graded Gleason score was found in 16 cases (42.1%) where- as a downgraded Gleason score occurred in 1 case (2.6%), when compared with the Gleason score from the biopsy (Table 2). Eleven cases (28.9%) of Gleason score 7 (3+4) and five cases (13.2%) of Gleason score 7 (4+3) were ob- served. Six cases of Gleason score 7 (3+4) and one case of Gleason score 7 (4+3) showed prostate capsule invasion and one case of Gleason score 7 (4+3) had seminal vesicle invasion. The inaccuracy of the contemporary Epstein crite- Yonsei Med J http://www.eymj.org Volume 53 Number 2 March 2012 359