Seock Hwan Choi

Risk factors for the development of urethrocutaneous fistula after hypospadias repair: a retrospective study.

Purpose The purpose of this study was to investigate the risk factors for urethrocutaneous fistula development after hypospadias repair. Materials and Methods Between January 1990 and May 2010, 348 patients underwent hypospadias repair. This study included 294 patients who were followed up for more than 6 months. Potential risk factors for the development of fistula after operation included age, location of hypospadias, type of hypospadias repair, suture materials and methods, methods and duration of catheterization, combined congenital urologic disorders, timing of presentation and repair of fistula, and location of fistula. Data were analyzed retrospectively. Binary logistic regression analysis was used for univariate and multivariate analysis. Results Out of 294 patients, 63 patients (21.4%, 63/294) developed urethrocutaneous fistulas after hypospadias repair. In the univariate analysis, fistula formation was statistically related with type of hypospadias and type of hypospadias repair. In the multivariate analysis with stratification by hypospadias site, however, only the location of hypospadias was a significant independent risk factor in urethrocutaneous fistula development after hypospadias repair (p<0.001). Conclusions Our results suggest that the risk of developing urethrocutaneous fistula after hypospadias repair is associated with the location of hypospadias (more proximal-type hypospadias). Type of hypospadias repair, suture materials, suture techniques, and number of other combined urologic disorders were not related to the development of urethrocutaneous fistulas.

Development of a porcine renal extracellular matrix scaffold as a platform for kidney regeneration

Acellular scaffolds, possessing an intact three-dimensional extracellular matrix (ECM) architecture and biochemical components, are promising for regeneration of complex organs, such as the kidney. We have successfully developed a porcine renal acellular scaffold and analyzed its physical/biochemical characteristics, biocompatibility, and kidney reconstructive potential. Segmented porcine kidney cortexes were treated with either 1% (v/v) Triton X-100 (Triton) or sodium dodecyl sulfate (SDS). Scanning electron microscopy showed both treatments preserved native tissue architecture, including porosity and composition. Swelling behavior was higher in the Triton-treated compared with the SDS-treated scaffold. Maximum compressive strength was lower in the Triton-treated compared with the SDS-treated scaffold. Attenuated total reflective-infrared spectroscopy showed the presence of amide II (-NH) in both scaffolds. Furthermore, richer ECM protein and growth factor contents were observed in the Triton-treated compared with SDS-treated scaffold. Primary human kidney cell adherence, viability, and proliferation were enhanced on the Triton-treated scaffold compared with SDS-treated scaffold. Following murine in vivo implantation, tumorigenecity was absent for both scaffolds after 8 weeks and in the Triton-treated scaffold only, glomeruli-like structure formation and neovascularity were observed. We identified 1% Triton X-100 as a more suitable decellularizing agent for porcine renal ECM scaffolds prior to kidney regeneration.

Solitary Testicular Metastasis of Prostate Cancer Mimicking Primary Testicular Cancer

We report a rare case of testicular metastasis from prostate cancer. A 68-year-old patient presented with a right testicular mass with discomfort. He had a history of robot-assisted laparoscopic radical prostatectomy and had received adjuvant radiation therapy and had been treated with androgen deprivation therapy continuously at another institution. We performed a right inguinal orchiectomy. The testicular mass was diagnosed as a metastasis from prostate carcinoma.

Human Urine-derived Stem Cells Seeded Surface Modified Composite Scaffold Grafts for Bladder Reconstruction in a Rat Model

We conducted this study to investigate the synergistic effect of human urine-derived stem cells (USCs) and surface modified composite scaffold for bladder reconstruction in a rat model. The composite scaffold (Polycaprolactone/Pluronic F127/3 wt% bladder submucosa matrix) was fabricated using an immersion precipitation method, and heparin was immobilized on the surface via covalent conjugation. Basic fibroblast growth factor (bFGF) was loaded onto the heparin-immobilized scaffold by a simple dipping method. In maximal bladder capacity and compliance analysis at 8 weeks post operation, the USCs-scaffoldheparin-bFGF group showed significant functional improvement (2.34 ± 0.25 mL and 55.09 ± 11.81 µL/cm H2O) compared to the other groups (2.60 ± 0.23 mL and 56.14 ± 9.00 µL/cm H2O for the control group, 1.46 ± 0.18 mL and 34.27 ± 4.42 µL/cm H2O for the partial cystectomy group, 1.76 ± 0.22 mL and 35.62 ± 6.69 µL/cm H2O for the scaffold group, and 1.92 ± 0.29 mL and 40.74 ± 7.88 µL/cm H2O for the scaffoldheparin-bFGF group, respectively). In histological and immunohistochemical analysis, the USC-scaffoldheparin-bFGF group showed pronounced, well-differentiated, and organized smooth muscle bundle formation, a multi-layered and pan-cytokeratin-positive urothelium, and high condensation of submucosal area. The USCs seeded scaffoldheparin-bFGF exhibits significantly increased bladder capacity, compliance, regeneration of smooth muscle tissue, multi-layered urothelium, and condensed submucosa layers at the in vivo study.

Advanced Properties of Urine Derived Stem Cells Compared to Adipose Tissue Derived Stem Cells in Terms of Cell Proliferation, Immune Modulation and Multi Differentiation

Adipose tissue stem cells (ADSCs) would be an attractive autologous cell source. However, ADSCs require invasive procedures, and has potential complications. Recently, urine stem cells (USCs) have been proposed as an alternative stem cell source. In this study, we compared USCs and ADSCs collected from the same patients on stem cell characteristics and capacity to differentiate into various cell lineages to provide a useful guideline for selecting the appropriate type of cell source for use in clinical application. The urine samples were collected via urethral catheterization, and adipose tissue was obtained from subcutaneous fat tissue during elective laparoscopic kidney surgery from the same patient (n = 10). Both cells were plated for primary culture. Cell proliferation, colony formation, cell surface markers, immune modulation, chromosome stability and multi-lineage differentiation were analyzed for each USCs and ADSCs at cell passage 3, 5, and 7. USCs showed high cell proliferation rate, enhanced colony forming ability, strong positive for stem cell markers expression, high efficiency for inhibition of immune cell activation compared to ADSCs at cell passage 3, 5, and 7. In chromosome stability analysis, both cells showed normal karyotype through all passages. In analysis of multi-lineage capability, USCs showed higher myogenic, neurogenic, and endogenic differentiation rate, and lower osteogenic, adipogenic, and chondrogenic differentiation rate compared to ADSCs. Therefore, we expect that USC can be an alternative autologous stem cell source for muscle, neuron and endothelial tissue reconstruction instead of ADSCs.

Efficacy and Tolerability of Tamsulosin 0.4 mg in Patients with Symptomatic Benign Prostatic Hyperplasia.

Purpose To evaluate the efficacy and tolerability of tamsulosin 0.4 mg once daily in Korean patients with symptomatic benign prostatic hyperplasia (BPH) and investigate whether tamsulosin 0.4 mg can improve symptoms in patients with refractory lower urinary tract symptoms (LUTS) who were previously receiving tamsulosin 0.2 mg once daily. Materials and Methods A total of 116 patients from 3 urology centers participated. All study subjects entered a nonblind phase consisting of 8 weeks of tamsulosin 0.2 mg monotherapy followed by an additional 8 weeks of tamsulosin 0.2 mg (0.2 mg group) or 8 weeks of tamsulosin 0.4 mg (0.4 mg group). At week 8, we chose the 0.4 mg group on the basis of International Prostate Symptom Score (IPSS), quality of life (QoL), maximal urinary flow rate (Qmax), and adverse effects. At week 16, we compared the efficacy and tolerability of tamsulosin between the 0.2 and 0.4 mg groups. Results A total of 26 patients (22.4%) were escalated to tamsulosin 0.4 mg at week 8. There were significant differences in IPSS, QoL, and Qmax at week 8 in both groups. There were significant differences in improvement in IPSS, QoL, Qmax, and postvoid residual urine volume from baseline to week 16 in both groups. There were no significant differences in efficacy or tolerability between the groups at week 16. Conclusions Our trial demonstrated that tamsulosin 0.4 mg has favorable efficacy and tolerability in Korean patients with symptomatic BPH refractory to tamsulosin 0.2 mg. No patients experienced any serious adverse effects when we escalated the dose of tamsulosin to 0.4 mg.

Clinical Significance of Subclassification of Papillary Renal Cell Carcinoma: Comparison of Clinicopathologic Parameters and Oncologic Outcomes Between Papillary Histologic Subtypes 1 and 2 Using the Korean Renal Cell Carcinoma Database

Micro‐Abstract The aim of the present study was to investigate the clinical significance of the subclassification of papillary renal cell carcinoma (pRCC) in a multi‐institutional study of 274 Korean patients with pRCC. Type 2 pRCC displayed more aggressive clinicopathologic characteristics; however, no significant differences in prognosis were found between types 1 and 2 pRCC. Among patients with pRCC, the pathologic T stage was the only prognosticator. Introduction: The aims of the present study were to compare the clinicopathologic characteristics between type 1 and type 2 papillary renal cell carcinoma (pRCC) and to evaluate the effect of the subclassification of pRCC on the oncologic outcomes after surgery. Materials and Methods: The records of 274 patients with pRCC in the Korean renal cell carcinoma (KORCC) database were included for evaluation. Of the 274 patients, 118 had type 1 pRCC and 156 had type 2 pRCC. The patient characteristics, including clinicopathologic parameters, were investigated, and the oncologic outcomes were evaluated. Results: The mean patient age was significantly older in the type 2 pRCC group. Compared with type 1 pRCC tumors, type 2 pRCC tumors were more often localized to the renal hilum (P = .030). Patients with type 2 pRCC had a greater incidence of Fuhrman grade 3 and 4 tumors than those with type 1 pRCC (78.8% vs. 22.8; P < .001). Tumor necrosis and capsular invasion were more frequently found in type 2 pRCC (P = .008 and P = .007, respectively). At a mean follow‐up period of 38.0 months (interquartile range, 11.8‐57.3 months), the subclassification of pRCC did not influence the prognosis of patients with pRCC. Conclusion: From the information available in the KORCC database, we identified significant differences in clinicopathologic variables, including age, Fuhrman grade, tumor location, tumor necrosis, and capsular invasion between type 1 and 2 pRCC. Although type 2 pRCC had more aggressive clinicopathologic characteristics, subclassification of pRCC did not affect the oncologic outcomes.

Decreased selenium-binding protein 1 mRNA expression is associated with poor prognosis in renal cell carcinoma.

BackgroundThe anticancer effects of selenium may be mediated by selenium-binding proteins, such as SELENBP1. The association between SELENBP1 expression levels and clinicopathologic parameters was assessed in renal cell carcinoma (RCC).MethodsSELENBP1 mRNA expression was measured with real-time quantitative polymerase chain reaction (qPCR) in 139 specimens of primary RCC and 59 specimens of donor-matched normal-appearing kidney tissues. The prognostic effect of SELENBP1 levels was evaluated with Kaplan–Meier and multivariate Cox regression analyses.ResultsSELENBP1 mRNA levels were significantly lower in tumor tissues than in matched normal kidney tissues (P < 0.001) and significantly inversely correlated with pathologic (T-stage and Fuhrman grade) and prognostic variables (progression and cancer-specific death). Kaplan–Meier estimates showed that low SELENBP1 expression was significantly correlated with cancer-specific death (log-rank test, P = 0.014), and a multivariate Cox regression model revealed that SELENBP1 expression was an independent predictor of cancer-specific death (HR, 0.111; P = 0.006).ConclusionsSELENBP1 might play a role in tumor suppression and could be a useful prognostic factor in RCC.

Risk factors for hypertensive attack during pheochromocytoma resection

Purpose We aimed to retrospectively evaluate the risk factors for hypertensive attack during adrenalectomy in patients with pheochromocytoma. Despite the development of newer surgical and anesthetic techniques for the management of pheochromocytoma, intraoperative hypertensive attack continues to present a challenge. Materials and Methods Data from 53 patients diagnosed with pheochromocytoma at Kyungpook National Uriversity Medical Center between January 2000 and June 2012 were retrospectively analyzed. The subjects were divided into 2 groups depending on the presence or absence of hypertensive attack at the time of surgery. Patient demographic characteristics and preoperative evaluations were assessed for their prognostic relevance with respect to hypertensive attack. A univariate analysis was conducted, and a multivariate logistic regression analysis was also performed. Results In the univariate analysis, systolic blood pressure at presentation, preoperative hormonal status (including epinephrine, norepinephrine, vanillylmandelic acid, and metanephrine levels in a 24-hour urine sample), tumor size, and postoperative systolic blood pressure were significantly associated with the development of hypertensive attack. In the multivariate analysis, preoperative epinephrine level and tumor size were independent factors that predicted hypertensive attack. The highest odds ratio for tumor size (2.169) was obtained at a cutoff value of 4.25 cm and the highest odds ratio for preoperative epinephrine (1.020) was obtained at a cutoff value of 166.3 µg/d. Conclusions In this study, a large tumor size and an elevated preoperative urinary epinephrine level were risk factors for intraoperative hypertensive attack in patients with pheochromocytoma.

Role of Prostate-Specific Antigen Change Ratio at Initial Biopsy as a Novel Decision-Making Marker for Repeat Prostate Biopsy

Purpose Prostate biopsy is used to confirm the prostate cancer. Although first biopsy result was benign, repeat biopsy is recommended for the patient who has higher risk of prostate cancer. In this study, we investigated the PSA change ratio (post-biopsy PSA to baseline PSA) whether it could be predictive factor of prostate cancer and helpful when decided to perform repeat biopsy. Materials and Methods 151 patients, first diagnosed as benign, but underwent repeat biopsy due to clinical suspicion of prostate cancer were included. Post-biopsy PSA was checked 60 minutes later after biopsy. PSA change ratio was defined as post-biopsy PSA to baseline PSA. According to results of repeat biopsy, patients were divided into benign group (group A) and cancer groups (group B). Between two group baseline PSA, PSA density, post-biopsy PSA and PSA change ratio were compared, and most effective cut-off value was analyzed using receiver operating characteristic (ROC). Results 129 men were benign, 22 men were prostate cancer according to results of repeat biopsy. Between two groups, post-biopsy PSA and PSA change ratio were statically significant differences. (p<0.001, <0.001) The effective cut-off value was 3.0, 3.5 and 4.0 according to ROC. At ROC curve, PSA change ratio was statistically significant for diagnosis of prostate cancer. (AUC 0.800, p<0.001). Conclusions PSA change ratio is thought be a predictive factor for prostate cancer. If the PSA change ratio was less than 3.0-4.0, repeat biopsy should be considered to confirm the diagnosis.