Jung Keun Lee

Prostate-specific antigen vs prostate-specific antigen density as a predictor of upgrading in men diagnosed with Gleason 6 prostate cancer by contemporary multicore prostate biopsy

Study Type – Diagnostic (validating cohort)

Stratification of patients with intermediate-risk prostate cancer.

To identify an appropriate risk stratification system for intermediate‐risk prostate cancer (PCa).

Impact of Tamsulosin on Ureter Stone Expulsion in Korean Patients: A Meta-Analysis of Randomized Controlled Studies

Purpose Using meta-analysis, the studys aim was to evaluate the efficacy of tamsulosin, an alpha-blocker, in the treatment of ureteral stones with or without shockwave lithotripsy (SWL) in Korean patients. Materials and Methods Relevant randomized controlled studies published through June 2011 were identified in a search of MEDLINE, KoreaMed, and the Korean Medical Database. No language restriction was applied. Only randomized controlled trials conducted with Korean patients were eligible for the analysis. The primary outcome assessed was the stone clearance rate. Two reviewers independently assessed the quality of the study and extracted the data. Meta-analysis was conducted by using R, version 2.13.0. Results A total of 6 articles were selected as being suitable for evaluation. Pooling of the trials demonstrated a 43% higher expulsion rate for tamsulosin treatment compared to a control group (risk ratio [RR], 1.43; 95% confidence interval [CI]: 1.24 to 1.65). Similar results were obtained in all subgroup analyses according to stone location (upper: RR, 1.31; 95% CI, 1.02 to 1.68, lower: RR, 1.50; 95% CI, 1.20 to 1.88) or concomitant SWL (yes: RR, 1.38; 95% CI, 1.14 to 1.68, no: RR, 1.48; 95% CI, 1.21 to 1.83). Conclusions This meta-analysis of randomized controlled studies provides a high level of evidence supporting the suggestion that treatment with tamsulosin augments the stone expulsion rate for ureter stones with or without SWL in a Korean population. However, a high-quality, large-scale, multicenter, randomized controlled trial is warranted to fully support this hypothesis.

Intraprostatic locations of tumor foci of higher grade missed by diagnostic prostate biopsy among potential candidates for active surveillance

To establish optimal biopsy scheme for selection of candidates for active surveillance (AS) among prostate cancer (PCa) patients, information on topographical distribution of tumor foci of higher grade missed by contemporary biopsy amongst potential candidates of AS would certainly be useful. Thus we analyzed topographic distribution of tumor foci by examining prostatectomy specimens in 444 patients who underwent radical prostatectomy for low risk PCa. Anterior and posterior prostate areas were demarcated by a horizontal line drawn at midpoint of prostatic urethra. Among 444 subjects, patients with upgrading showed relatively higher prevalence of index tumor foci in anterior prostate than those without upgrading, though not reaching statistical significance (p = 0.252). Meanwhile, among 135 (30.4%) patients with very low risk PCa, patients with upgrading showed significantly higher prevalence of index tumor foci in anterior prostate than those without upgrading (52.2% vs 33.8%; p = 0.031). In conclusions, tumor foci of higher grade missed by diagnostic biopsy were mostly located in anterior prostate among very low risk PCa patients. Such finding would be concrete evidence to support the notion that more efforts are needed to increase accuracy in detecting tumor foci in anterior prostate among potential candidates for AS.

Prostate cancer detection rate in patients with fluctuating prostate-specific antigen levels on the repeat prostate biopsy

Purpose: To evaluate whether the risk of prostate cancer was different according to the pattern of fluctuation in prostate-specific antigen (PSA) levels in patients undergoing repeat transrectal ultrasound-guided prostate biopsy (TRUS-Bx). Methods: From March 2003 to December 2012, 492 patients underwent repeat TRUS-Bx. The patients were stratified into 3 groups based on the PSA fluctuation pattern: group 1 (continuous elevation of PSA, n=169), group 2 (PSA fluctuation with PSA velocity [PSAV]≥1.0 ng/mL/yr, n=123), and group 3 (PSA fluctuation with PSAV<1.0 ng/mL/yr, n=200). Results: Prostate cancer was detected in 112 of 492 patients (22.8%) in the repeat biopsy set. According to the PSA fluctuation pattern, prostate cancer detection rates at repeat TRUS-Bx were 29.6% (50/169) for patients with continuously increasing PSA, 30.1% (37/123) for PSA fluctuation with PSAV ≥1.0 ng/mL/yr, and 12.5% (25/200) for PSA fluctuation with PSAV <1.0 ng/mL/yr. Multivariate analysis showed that PSA fluctuation pattern and high grade prostatic intraepithelial neoplasia at initial TRUS-Bx were the predictive parameters for positive repeat biopsies. Among the 96 patients (85.7%) who underwent radical prostatectomy, no significant differences in pathologic outcomes were found according to the PSA fluctuation pattern. Conclusions: The current study shows that the risk of prostate cancer at repeat TRUS-Bx was higher in men with a fluctuating PSA level and PSAV≥1.0 ng/mL/yr than in those with a fluctuating PSA level and PSAV<1.0 ng/mL/yr.

A New Sliding-Loop Technique in Renorrhaphy for Partial Nephrectomy A Feasibility Study in a Porcine Model

Background. We developed a sliding-loop technique that narrowed both sides of the parenchyma in a porcine model and compared it with the conventional sliding-clip technique. Methods. Three pigs (30-40 kg) were reused following another experiment conducted by the same researchers. Bilateral kidneys were harvested within 30 minutes after euthanasia. Two partial nephrectomies per kidney were performed on opposite surfaces. All kidney defects were of the same size (diameter of 2.5-3 cm with a depth of 1.0-1.5 cm). The sliding-clip technique and sliding-loop technique were performed separately. In the sliding-loop technique, we created a 1-cm loop at the end of a Vicryl and placed a tetrafluoroethylene polymer pledget in front of the knots passing through the needle. The needle then crossed the loop after passing through the renal parenchyma. A Weck clip was placed and slid on one side to tighten the suture. Tightening was controlled with an equivalent force using a digital push-pull gauge. Three stitches were placed at each renorrhaphy site. The distance between repaired renal surfaces was measured at 5 different points (3 suture sites and 2 middle sites between sutures). Results. The results of the 2 techniques were compared by using the independent t test. The mean distance between renal surfaces was significantly narrower in the sliding-loop technique than in the conventional technique (1.80 ± 1.08 mm vs 5.28 ± 2.46 mm, P < .001). Conclusion. In the porcine model, the sliding-loop technique more effectively closed the partial nephrectomy defects compared with the conventional sliding-clip technique.

Comparison of the Width of Peritumoral Surgical Margin in Open and Robotic Partial Nephrectomy: A Propensity Score Matched Analysis

Background To compare the surgical margin status after open partial nephrectomy (OPN) and robotic partial nephrectomy (RPN) performed in patients with T1a renal cell carcinoma (RCC). Methods This was a propensity score-matched study including 702 patients with cT1a RCC treated with partial nephrectomy (PN) between May 2003 and July 2015. Perioperative parameters, including surgical margin width after PN, were compared between two surgical methods. After determining propensity score for tumor size and location, the width of peritumoral surgical margin was investigated. Multivariate logistic analysis to predict peritumoral surgical margin less than 1mm was analyzed. Results The mean width of peritumoral surgical margin was 2.61 ± 2.15 mm in OPN group (n = 385), significantly wider than the 2.29 ± 2.00 mm of RPN group (n = 317) (p = 0.042). The multivariate analysis showed surgical methods was significant factors to narrow surgical margin less than 1mm (p = 0.031). After propensity score matching, the surgical margin width was significantly longer in OPN (2.67 ± 2.14 mm) group than RPN (2.25 ± 2.03 mm) group (p = 0.016). A positive resection margin occurred in 7 (1.8%) patients in the OPN group and 4 (1.3%) in the RPN group. During the median follow-up of 48.3 months, two patients who underwent OPN had tumor bed recurrence. Conclusions RPN may result in a narrower peritumoral surgical margin than OPN. Further investigation on the potential impact of such a phenomenon should be performed in a larger-scale study.

Accurate Risk Assessment of Patients with Pathologic T3aN0M0 Renal Cell Carcinoma

To develop a more precise risk-stratification system by investigating the prognostic impact of tumor growth within fatty tissues surrounding the kidney and/or renal vein. We conducted a retrospective review of the medical records of 211 patients with a pathologic diagnosis of T3aN0M0RCC among 4,483 renal cell carcinoma (RCC) patients from February 1988 to December 2015 according to the number of T3a pathologies—extrarenal fat invasion (EFI) and/or renal venous invasion (RVI). During a mean follow-up duration of 38.8 months, the patients with both pathologies (EFI + RVI) had lower recurrence free survival (RFS) rate than those with only a single pathology (p = 0.001). Using multivariable Cox regression analysis, the presence of both factors was shown to be an independent predictor of RFS (HR = 1.964, p = 0.032); cancer specific survival rate was not different among patients with EFI and/or RVI. Patients with pathologic T3aN0M0 RCC presenting with both EFI and RVI were at an increased risk of recurrence following nephrectomy. Therefore, pathologic T3a RCC could be sub-divided into those with favorable and unfavorable disease according to presence of EFI and/or RVI pathologies.

MP49-05 IMPACT OF PROLONGED ISCHEMIC TIME ON CHRONIC KIDNEY DISEASE FOLLOWING PARTIAL NEPHRECTOMY: A MATCHED-PAIR COMPARISON

INTRODUCTION AND OBJECTIVES: To preserve renal function, partial nephrectomy is recommended to patients with small renal masses. However, controversy still exists as to whether prolonged ischemic time adversely affects the incidence of chronic kidney disease. We assessed the effect of prolonged ischemic time to global renal function following partial nephrectomy. METHODS: We reviewed data from 1,588 patients who underwent open or robotic partial nephrectomy for clinical T1 renal tumor with normal renal function (estimated glomerular filtration rate [eGFR] 60 mL/min/1.732). Patients were subjected to group A (ischemic time 30 minutes) or group B (ischemic time > 30 minutes). Propensity score matching was used to adjust for potential confounders, which resulted in 320 patients in each group. Postoperative renal function was evaluated at the last follow-up visit. Multivariate analysis was used to determine predictors for the newly acquired CKD (eGFR < 60 mL/min/1.732). RESULTS: In the groups A and B, mean ischemic time was 19.8 and 40.2 minutes respectively. There were no statistically significant differences in other baseline variables between the groups. After a median follow-up of 37 months, mean postoperative eGFR was similar (84.5 vs. 83.2 mL/min/1.732, p 1⁄4 0.424) and the rate of CKD did not differ in the two groups (6.3% vs. 7.2%, p 1⁄4 0.636). Prolonged ischemic time did not affect the newly acquired CKD among the open partial nephrectomy subgroup (p 1⁄4 0.847) and those with robotic partial nephrectomy (p 1⁄4 0.160). Moreover, dividing ischemic time into five groups ( 20, 21-30, 31-40, 41-50, and 50 minutes) provided no further information on new onset CKD (7.5%, 4.8%, 7.0%, 7.9%, and 6.5%, p 1⁄4 0.865) compared with the two groups with a cut-off at 30 minutes. CONCLUSIONS: In patients with a normal baseline renal function, prolonged ischemic time is not an independent predictor of CKD following partial nephrectomy.

Association of the neutrophil-to-lymphocyte ratio and prostate cancer detection rates in patients via contemporary multi-core prostate biopsy.

The aim of this study was to determine whether the neutrophil-to-lymphocyte ratio (NLR), a measure of the systemic inflammatory response is associated with the overall prostate cancer detection rate in men who underwent contemporary multi (≥12)-core transrectal ultrasound (TRUS) biopsy. We reviewed the records of 3913 patients with initial prostate-specific antigen (PSA) levels ranging from 4 to 10 ng ml−1 who underwent TRUS-guided prostate biopsy between April 2006 and May 2014. NLR was calculated by prebiopsy neutrophil and lymphocyte counts. We excluded patients who had evidence of acute prostatitis, a history of prostate surgery, and any systemic inflammatory disease. A multivariate logistic regression model was used to analyze prostate cancer detection. After adjusting for confounding factors, predictive values were determined according to the receiver operating characteristic-derived area under the curve, both including and excluding the NLR variable. In univariate analyses, NLR was a significant predictor of prostate cancer detection (P < 0.001). In multivariate analyses, a higher NLR was significantly associated with prostate cancer detection after adjusting for other factors (OR = 1.372, P= 0.038). The addition of NLR increased the accuracy from 0.712 to 0.725 (P = 0.005) in the multivariate model for prostate cancer detection. NLR may be a potentially useful clinical marker in the detection of prostate cancer among men with a PSA level in the 4-10 ng ml−1 range. These findings are derived from a retrospective analysis and should be validated in larger populations through prospective studies.