Dong Deuk Kwon

Prevalence and Associated Factors of Overactive Bladder in Korean Children 5-13 Years Old: A Nationwide Multicenter Study

OBJECTIVES To estimate the prevalence of overactive bladder (OAB) in Korean children, 5-13 years of age, and to assess the associated factors for OAB. METHODS A randomly selected cross-section study was conducted in 26 kindergartens and 27 elementary schools nationwide in Korea. A total of 19 240 children were included; a parent was asked to complete the questionnaires, which included items about OAB and voiding and defecating habits. OAB was defined as urgency with or without urge incontinence, usually with increased daytime frequency and nocturia (International Childrens Continence Society, 2006). Its prevalence and associated factors were also investigated. RESULTS The response rate for the questionnaires was 85.84%. The overall prevalence of OAB was 16.59%. The prevalence of OAB decreased with age from 22.99% to 12.16% (P = .0001). The overall incidence of wet and dry OAB was 26.97% and 73.03%, respectively. Compared with normal children, those with OAB had a greater prevalence of nocturnal enuresis, constipation, fecal incontinence, urinary tract infection, delayed bladder control, and poor toilet facilities (P < .05). The incidence of increased daytime frequency and urge incontinence was 3.69% and 2.31% (P = .009) and 26.97% and 14.78% (P = .0001) in OAB and non-OAB children, respectively. The corresponding prevalence decreased with age from 5.04% to 3.06% and from 45.74% to 18.50% in OAB children (P = .0001). CONCLUSIONS The overall prevalence of OAB in Korean children, 5-13 years of age, was 16.59% and decreased with age. Nocturnal enuresis, constipation, fecal incontinence, history of urinary tract infection, delayed bladder control, and poor toilet facilities might be factors associated with the development of OAB.

Impact of diabetes mellitus on recurrence and progression in patients with non-muscle invasive bladder carcinoma: A retrospective cohort study

Objective:  The aim of the present study was to investigate the relationship between diabetes mellitus (DM) and tumor features in patients with non‐muscle invasive bladder cancer (NMIBC).

An Epidemiologic Study of Voiding and Bowel Habits in Korean Children: A Nationwide Multicenter Study

OBJECTIVES To evaluate the prevalence of abnormal voiding and bowel habits in healthy children, and to identify possible relationships between personal and familial factors and voiding and/or bowel habits. METHODS A randomly selected cross-sectional study was conducted in 19,240 children (5-13 years old) nationwide in the Republic of Korea. Parents were asked to complete questionnaires, which included items about nocturnal enuresis, daytime dysfunctional voiding symptoms (DVSs), and abnormal bowel habits (ABHs). Rates and associated factors were investigated. RESULTS The overall rates of DVS, ABH, and of both were 46.4%, 31.3%, and 18.4%, respectively, and nocturnal enuresis was reported in 919 (5.6%). Daytime dysfunctional voiding symptoms were as follows: increased voiding frequency in 419 (2.5%), decreased voiding frequency in 720 (4.4%), urgency in 2740 (16.6%), daytime incontinence in 1854 (11.2%), urge incontinence in 2775 (16.8%), and holding maneuvers or postponed voiding in 3888 (23.5%). ABHs were as follows: constipation by frequency in 1103 (6.7%), constipation by the Bristol scale in 1941 (11.8%), fecal incontinence in 1293 (7.8%), and difficult or painful defecation in 2609 (15.8%). Delayed stool control, history of urinary tract infection, and a double-income family were positively associated with DVS or ABH or both. Furthermore, fathers with a low level of education and a low income were found to be associated with higher risk of ABH or DVS or both. CONCLUSIONS Delayed stool control, a history of urinary tract infection, a low paternal level of education, a double-income family, and a lower family income had a negative effect on voiding or bowel habits in children.

Dimethoxycurcumin, a Structural Analogue of Curcumin, Induces Apoptosis in Human Renal Carcinoma Caki Cells Through the Production of Reactive Oxygen Species, the Release of Cytochrome c, and the Activation of Caspase-3

Purpose Curcumin (Cur) has been reported to induce apoptosis in human renal carcinoma Caki cells. Dimethoxycurcumin (DMC), one of several synthetic Cur analogues, has been reported to have increased metabolic stability over Cur. We determined whether DMC, like Cur, induces apoptosis in Caki cells and also compared the apoptosis-inducing activity of DMC with that of Cur. Materials and Methods Caki cells were treated with DMC possessing four methoxy groups, Cur possessing two methoxy groups, or bis-demethoxycurcumin (BMC), which lacks a methoxy group. Cell viability was measured by using a methyltetrazolium assay. Flow cytometry and the caspase-3 activity assay were used to detect apoptosis. The release of cytochrome-c (Cyt c) was detected by Western blot analysis. The production of reactive oxygen species (ROS) was measured by flow cytometry. Results DMC, Cur, and BMC reduced cell viability and induced apoptosis, but the potency varied; DMC was the most potent compound, followed by Cur and BMC. ROS production, Cyt c release, and caspase-3 activity were increased, again in the order DMC>Cur>BMC. N-Acetylcysteine, a potent antioxidant, inhibited ROS production, Cyt c release, caspase-3 activation, and apoptosis induction in DMC-treated cells. Conclusions These results indicate that DMC, like the original form of Cur, may induce apoptosis in human renal carcinoma Caki cells through the production of ROS, the release of mitochondrial Cyt c, and the subsequent activation of caspase-3. In addition, DMC is more potent than Cur in the ability to induce apoptosis.

Relationship between the Glutathione-S-Transferase P1, M1, and T1 Genotypes and Prostate Cancer Risk in Korean Subjects

Purpose The glutathione-S-transferase (GST)P1, GSTM1, and GSTT1 genotypes have been associated with an increased risk of prostate, bladder, and lung cancers. The aim of this study was to investigate the association between the GSTP1, GSTM1, and GSTT1 genotypes and the risk of prostate cancer in Korean men. Materials and Methods The study group consisted of 166 patients with histologically confirmed prostate cancer. The control group consisted of 327 healthy, cancer-free individuals. The diagnosis of prostate cancer was made by transrectal ultrasound-guided biopsy. Patients with prostatic adenocarcinoma were divided into organ-confined (≤pT2) and non-organ-confined (≥pT3) subgroups. The histological grades were subdivided according to the Gleason score. The GSTP1, GSTM1, and GSTT1 genotypes were determined by using polymerase chain reaction-based methods. The relationship among GSTP1, GSTM1, and GSTT1 polymorphisms and prostate cancer in a case-control study was investigated. Results The frequency of the GSTM1 null genotype in the prostate cancer group (54.2%) was higher than in the control group (odds ratio=1.53, 95% confidence interval=1.20-1.96). The comparison of the GSTP1, GSTM1, and GSTT1 genotypes and cancer prognostic factors, such as staging and grading, showed no statistical significance. Conclusions An increased risk for prostate cancer may be associated with the GSTM1 null genotype in Korean men, but no association was found with the GSTT1 or GSTP1 genotypes.

Use of the NMP22 BladderChek test in the diagnosis and follow-up of urothelial cancer: a cross-sectional study.

OBJECTIVES To investigate the efficacy of the nuclear matrix protein (NMP) 22 BladderChek test (NMP22BC) in the detection and follow-up of urothelial carcinoma. MATERIAL AND METHODS A total of 1021 patients who underwent the NMP22BC, cytology, and cystoscopy, were studied. We divided the patients into 2 groups: group I consisted of 597 patients who were being followed up for previous urothelial carcinoma, and group II consisted of 424 patients with hematuria. The sensitivity and specificity of the NMP22BC, cytology, and the combination (NMP22BC + cytology) were compared. RESULTS Of the 1021 patients, 131 were diagnosed with urothelial cancer. The overall sensitivities for the NMP22BC, cytology, and the combination were 32.1%, 38.2%, and 52.7%, respectively. In group I, the sensitivity of the NMP22BC was lower than the sensitivity of cytology (22.58% vs 35.5%); there was no difference between the sensitivity of the NMP22BC and that of cytology in group II (40.58% vs 40.58%). For the combination, the sensitivity was greater than that of either test alone in both groups (46.77% and 57.97% in groups I and II, respectively). The sensitivity of the NMP22BC was greater than that of cytology (22.6% vs 13.2%) for low-grade bladder cancer. CONCLUSIONS The NMP22BC has lower sensitivity than cytology. However, the sensitivity of NMP22BC in low-grade tumors was higher than that of cytology. Therefore, when the NMP22BC is combined with cytology, the sensitivity for detecting urothelial carcinoma is increased, which implies that this combination may be useful in the screening and follow-up of urothelial carcinoma.

Comparison of laparoscopic and open partial nephrectomies in t1a renal cell carcinoma: a korean multicenter experience.

Purpose We analyzed a series of patients who had undergone laparoscopic partial nephrectomies (LPNs) and open partial nephrectomies (OPNs) to compare outcomes of the two procedures in patients with pathologic T1a renal cell carcinomas (RCCs). Materials and Methods From January 1998 to May 2009, 417 LPNs and 345 OPNs were performed on patients with small renal tumors in 15 institutions in Korea. Of the patients, 273 and 279 patients, respectively, were confirmed to have pT1a RCC. The cohorts were compared with respect to demographics, peri-operative data, and oncologic and functional outcomes. Results The demographic data were similar between the groups. Although the tumor location was more exophytic (51% vs. 44%, p=0.047) and smaller (2.1 cm vs. 2.3 cm, p=0.026) in the LPN cohort, the OPN cohort demonstrated shorter ischemia times (23.4 min vs. 33.3 min, p<0.001). The LPN cohort was associated with less blood loss than the OPN cohort (293 ml vs. 418 ml, p<0.001). Of note, two patients who underwent LPNs had open conversions and nephrectomies were performed because of intra-operative hemorrhage. The decline in the glomerular filtration rate at the last available follow-up (LPN, 10.9%; and OPN, 10.6%) was similar in both groups (p=0.8). Kaplan-Meier estimates of 5-year local recurrence-free survival (RFS) were 96% after LPN and 94% after OPN (p=0.8). Conclusions The LPN group demonstrated similar rates of recurrence-free survival, complications, and postoperative GFR change compared with OPN group. The LPN may be an acceptable surgical option in patients with small RCC in Korea.

Is a Decreased Serum Testosterone Level a Risk Factor for Prostate Cancer? A Cohort Study of Korean Men

Purpose To investigate patients who had transrectal ultrasonography (TRUS)-guided prostate biopsy to define the role of the serum testosterone level in predicting prostate cancer risk and its association with a high Gleason score. Materials and Methods A total of 568 patients who underwent prostate biopsy were entered in this study. We divided the patients into two groups according to serum testosterone level (median level, 3.85 ng/ml): the high-testosterone group (n=285) and the low-testosterone group (n=283). Multivariate regression analysis was used to define the effect of age, prostate volume, serum prostate-specific antigen (PSA) level and PSA density, and serum testosterone level on the risk of prostate cancer and a high Gleason score. Results Baseline characteristics did not differ significantly between the two groups. Compared with the high-testosterone group, the low-testosterone group had a significantly higher prostate cancer incidence (38.9% vs. 29.5%, p=0.018). Factors associated with an increased risk of prostate cancer were increased age (odds ratio [OR]=1.08, 95% confidence interval [CI]=1.25-3.16, p=0.001), a high serum PSA level (OR=3.35, 95% CI=2.63-4.25, p=0.001), a low prostate volume (OR=0.183, 95% CI=0.11-0.30, p=0.001), and a low serum testosterone level (OR=1.99, 95% CI=1.25-3.16, p=0.001). Among these, only the serum PSA level was a strong predictor of high-grade prostate cancer (Gleason score ≥7) (OR=2.19, 95% CI=1.57-2.95, p=0.001). Conclusions Patients with lower levels of serum testosterone had a higher risk of prostate cancer than did patients with high serum testosterone. Even though a lower serum testosterone level was a predictor of prostate cancer risk, it was not associated with an increased risk of high-grade prostate cancer.

Usefulness of liquid-based preparation in urine cytology

Objective:  ThinPrep (TP), a liquid‐based cytological and non‐invasive technique to confirm the diagnosis of bladder cancer, is reported to be a better screening test than the conventional cytospin method. This study compared the new MonoPrep2 (MP), a liquid‐based cytological technique, with TP for diagnosing bladder cancer.

Factors associated with continuing medical therapy after transurethral resection of prostate.

OBJECTIVE To report the clinical characteristics of patients who have persistent lower urinary tract symptoms (LUTS) after surgery for benign prostatic hyperplasia (BPH) and continue their medical therapy postoperatively. MATERIALS AND METHODS We retrospectively studied 372 patients who underwent transurethral resection of prostate for LUTS/BPH in 8 institutions to determine the differences between patients who continued LUTS/BPH medications for >3 months after surgery and those who did not. Preoperative, intraoperative, and postoperative clinical parameters were assessed. The Student t test and chi square test were used to compare each parameter between patient groups. Multivariate logistic regression analysis was performed to identify risk factors for persistent LUTS and continuing medical therapy after surgery. RESULTS There were 205 patients (55.1%) who continued their LUTS/BPH medications for >3 months postoperatively. They reported poorer International Prostate Symptom Scores and uroflowmetry results after surgery. Multivariate analysis showed that age >70 years (odds ratio [OR], 2.474; P = .001), history of diabetes (OR, 1.949; P = .040), history of cerebrovascular accident (OR, 5.932; P = .001), any previous LUTS/BPH medication use (OR, 5.384; P = <0.001), and previous antimuscarinic drug use (OR, 2.962; P = .016) were significantly associated with symptom persistency and continuing medical therapy. CONCLUSION Many patients have persistent voiding dysfunction after surgical treatment for LUTS/BPH. Older age, history of diabetes, history of cerebrovascular accidents, and preoperative antimuscarinic drug uses are possible risk factors.