Jinsung Park

The Effectiveness of Silodosin for Nocturnal Polyuria in Elderly Men With Benign Prostatic Hyperplasia: A Multicenter Study

Purpose: To investigate improvement in nocturia and nocturnal polyuria in nocturnal polyuria patients after silodosin administration by using a 3-day frequency volume chart. Methods: This was a prospective multicenter study. We enrolled nocturnal polyuria patients (nocturnal polyuria index [NPi]>0.33), aged ≥60 years, diagnosed with the 3-day frequency volume charts of patients with benign prostatic hyperplasia taking α-blockers. Of the 54 patients, 30 (55.6%) completed the study according to the study protocol (per-protocol group), and 24 dropped out (dropout group). Results: Of the 24 patients in the dropout group, 5 withdrew consent due to side effects or lack of efficacy, 7 were lost to follow-up at 4 weeks, 8 were lost to follow-up at 12 weeks, and 4 dropped out due to failure to complete 3-day frequency volume charts at 12 weeks. In the per-protocol group, there was significant improvement in the International Prostate Symptom Score (IPSS), especially question numbers 1, 3, 4, 5, 6, 7, and the quality of life question (P=0.001, P=0.007, P<0.001, P=0.003, P=0.049, P<0.001, and P<0.001, respectively). The Leeds sleep evaluation questionnaire (LSEQ) score for the sleep question improved from 64.36 to 70.43 (P=0.039). The NPi reduced from 0.4005 to 0.3573 (P=0.027); however, in many cases, there was no improvement in nocturnal polyuria itself. In intention-to-treat analysis, there were significant improvements in IPSS and LSEQ in 45 patients. Conclusions: In elderly nocturnal polyuria patients, silodosin monotherapy exhibits good efficacy in improving nocturia and nocturnal polyuria; however, the mean NPi was still >0.33. Considering the high dropout rate of our study due to no implementation of 3-day frequency volume charts, prospective and large-scale studies are needed to confirm our results.

Prognostic Significance of CREB-Binding Protein and CD81 Expression in Primary High Grade Non-Muscle Invasive Bladder Cancer: Identification of Novel Biomarkers for Bladder Cancer Using Antibody Microarray.

High-grade (HG) bladder cancers (BCs) are genetically unstable and have an unpredictable course. The identification of prognostic factors in HG non-muscle invasive BC (NMIBC) is crucial for improving patients’ quality of life and preventing BC-specific mortality. Here, we used an antibody microarray (AbM) to identify novel candidate biomarkers in primary HG NMIBC and validated the prognostic significance of the candidate biomarkers. Three pairs of tissue samples from primary HG NMIBC and normal urothelium were analyzed using an AbM kit containing 656 antibodies, and differentially expressed proteins were identified. Among the 42 upregulated and 14 downregulated proteins with statistical significance in BC tissues, CREB-binding protein and CD81 were selected as representative upregulated and downregulated candidate biomarkers, respectively. We then validated the expression of these candidate biomarkers in primary human urothelial cells and BC cell lines by western blotting and immunofluorescence assays, and the results were consistent with the AbM expression profiles. Additionally, Kaplan-Meier survival using immunohistochemical data from an independent primary HG NMIBC cohort comprising 113 patients showed that expression of the 2 biomarkers was significantly associated with recurrence-free and progression-free survival. In multivariate analysis, the 2 biomarkers remained significant predictors for recurrence-free survival. Taken together, our findings suggest that expression of CREB-binding protein and CD81 in BC tissue specimens may have prognostic value in patients with primary HG NMIBC.

Comparison of postoperative estimated glomerular filtration rate between kidney donors and radical nephrectomy patients, and risk factors for postoperative chronic kidney disease

To compare post‐nephrectomy renal function between kidney donors and renal cell carcinoma patients, to evaluate trends in recovery, and to identify factors relevant to renal failure.

Practice Patterns of Urologists in Managing Korean Men Aged 40 Years or Younger With High Serum Prostate-specific Antigen Levels

OBJECTIVE To investigate the practice patterns of urologists in managing Korean men aged 40 years or younger with high serum prostate-specific antigen (PSA). MATERIALS AND METHODS Data were collected from general health screenings conducted at 4 university hospitals between 2004 and 2012. Eligibility criteria were Korean men aged≤40 years who were seen by urologists for high PSA (>2.5 ng/mL). After excluding individuals with chronic prostatitis and any infectious symptoms and/or signs, the practice patterns of urologists managing 237 eligible men were analyzed. RESULTS The most common practice was observation after antibiotics (40.5%), followed by reassurance (38.4%), prostate biopsy (PBx) after antibiotics (11.8%), PBx after PSA follow-up (7.6%), and immediate PBx (1.7%). Antibiotics were prescribed empirically to 124 patients (52.3%). Of the entire patients, 145 of 237 (61.2%) had at least 1 follow-up PSA, and the follow-up PSA with median interval of 43 days (interquartile range, 26-149) was higher than initial PSA in 66 of 145 (45.5%). Of the 98 patients undergoing follow-up PSA after initial antibiotic treatment, 53 (54.1%) experienced a decline in PSA, whereas 45 (45.9%) experienced a rise in PSA. PBx was performed in 50 of 237 (21.1%), and only a single case (2%) of prostate cancer was diagnosed. CONCLUSION In managing men≤40 years with high PSA, the most common practice pattern was observation after antibiotic treatment despite lack of evidences. Furthermore, 1 in 5 urologists performed PBx to rule out cancer. Given the very low prevalence of cancer in this age group, clear guidelines are needed for appropriate management and consistency of care.

The role of Kaposi’s sarcoma-associated herpesvirus infection in the proliferation of human bladder cancer cells

Existing evidence suggests a possible role of viruses in human bladder cancer development. Recently, Kaposi’s sarcoma-associated herpesvirus (KSHV) was reported to be the most frequently detected virus in bladder cancer tissue from Croatian patients on screening with the Lawrence Livermore Microbial Detection Array. In the current study, to investigate the functional roles of KSHV in bladder cancer, five bladder cancer cell lines were infected with KSHV and their tumour progression-associated changes investigated. Four KSHV-infected bladder cancer cell lines were established; two invasive bladder cancer cell lines showed higher proliferation rates than uninfected cells. Additionally, these KSHV-infected invasive bladder cancer cells showed a greater number of colonies, which were also significantly larger than those of uninfected cells, in a soft agar colony formation assay. cDNA microarray analysis showed that various genes associated with cell proliferation and cancer development were upregulated in these KSHV-infected bladder cancer cells. Taken together, we suggest that KSHV infection affects the proliferation of a subset of invasive bladder cancer cells and may therefore play a role in their oncogenic progression. Further studies are required to elucidate the exact mechanism used by KSHV to promote bladder cancer progression.

Latent Kaposi’s sarcoma-associated herpesvirus infection in bladder cancer cells promotes drug resistance by reducing reactive oxygen species

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the major etiologic agent of Kaposi’s sarcoma, primary effusion lymphoma, and multicentric Castleman’s disease. Recent studies have indicated that KSHV can be detected at high frequency in patient-derived bladder cancer tissue and might be associated with the pathogenesis of bladder cancer. Bladder cancer is the second most common cancer of the genitourinary tract, and it has a high rate of recurrence. Because drug resistance is closely related to chemotherapy failure and cancer recurrence, we investigated whether KSHV infection is associated with drug resistance of bladder cancer cells. Some KSHV-infected bladder cancer cell lines showed resistance to an anti-cancer drug, cisplatin, possibly as a result of down-regulation of reactive oxygen species. Additionally, drug resistance acquired from KSHV infection could partly be overcome by HDAC1 inhibitors. Taken together, the data suggest the possible role of KSHV in chemo-resistant bladder cancer, and indicate the therapeutic potential of HDAC1 inhibitors in drug-resistant bladder cancers associated with KSHV infection.

National Practice Pattern and Time Trends in Treatment of Upper Urinary Tract Calculi in Korea: a Nationwide Population-Based Study

Despite high prevalence of upper urinary tract calculi (UUTC), there are few studies regarding patterns of care in Asian populations. We investigated treatment patterns and time trends in patients with newly diagnosed UUTC in Korea using the National Health Insurance database that includes de-identified claims from a random 2% sample of the entire population (> 1 million people). A total of 14,282 patients who received active treatments, including shock wave lithotripsy (SWL), ureteroscopic surgery (URS), percutaneous nephrolithotomy (PNL), and uretero/pyelolithotomy (UPL), for newly diagnosed UUTC between 2003 and 2013 were included. The number of primary and all treated cases of UUTC significantly (43% and 103.3%, respectively) increased over the 10-year period. While patients undergoing SWL, URS, PNL, and UPL as primary treatment increased by 43.7%, 31.9%, 87.5%, and 0%, respectively, the relative proportion undergoing each treatment remained constant over the 10 years (SWL > 90%, URS 4.5% to 7.8%, PNL 0.4% to 1.0%, and UPL < 0.4%, respectively). Multinomial logistic regression analysis showed that age > 40 years (compared to age < 30 years) was significantly associated with URS, PNL, and UPL, rather than SWL, while patients living in urban or suburban/rural areas (compared to metropolitan) were significantly less likely to undergo URS and PNL. In summary, the majority of Korean patients underwent SWL as primary treatment for UUTC, and the predominant use of SWL remained steady over a 10-year period in Korea. Our results will be valuable in examining treatment patterns and time trends in Korean UUTC patients.

Can prostate-specific antigen kinetics before prostate biopsy predict the malignant potential of prostate cancer?

Purpose To predict the malignant potential of prostate cancer (PCa) according to prostate-specific antigen velocity (PSAV), PSA density (PSAD), free/total PSA ratio (%fPSA), and digital rectal examination (DRE). Materials and Methods From January 2009 to December 2012, 548 adult male patients were diagnosed with PCa by prostate biopsy at four hospitals in Korea. We retrospectively analyzed 155 adult male patients with an initial PSA level ≤10 ng/mL and whose PSA levels had been checked more than two times at least 6 months before they had been diagnosed with PCa, with test intervals of more than 3 months. Patients with a urinary tract infection, and patients who had previously undergone cystoscopy or surgery of the prostate were excluded. We separated patients into two groups according to Gleason sum [Gleason sum ≤7 (n=134) or Gleason sum ≥8 (n=21)] and the presence of extracapsular invasion [organ confined (n=129) or extracapsular invasion (n=26)]. Differences between the groups were compared. Results The group with a Gleason sum ≥8 or extracapsular invasion of PCa showed high PSAV and significantly lower %fPSA. There were no significant differences in PSAD and the presence of an abnormality on DRE between two groups. Conclusion In PCa patients treated with other therapies besides prostatectomy, a high PSA velocity and a low %fPSA may predict high grade PCa with a Gleason sum ≥8 or the presence of extracapsular invasion.

Which Patients Should We Follow up beyond 5 Years after Definitive Therapy for Localized Renal Cell Carcinoma

Purpose Up to 10% of recurrences develop beyond 5 years after curative treatment of localized renal cell carcinoma (RCC). Clinicopathologic features were evaluated to determine which factors are associated with late recurrence. Materials and Methods A total of 753 patients were diagnosed with localized RCC from January 2000 to June 2008. We enrolled 225 patients who were treated surgically and had a minimal recurrence-free survival of 60 months. Patients who had recurrence beyond 5 years after nephrectomy were defined as the late recurrence group and the remaining patients as the recurrence-free group. Multivariate logistic regression analyses and the Cox proportional hazard model were used for determination of features associated with late recurrence. Results In multivariate analyses, age older than 60 (p=0.030), Fuhrman grade ≥ 3 (p=0.042), and pT stage ≥ pT2 (p=0.010) showed statistical association with late recurrence. The Cox proportional hazard model showed significant differences in recurrence-free survival when we classified the patients based on pT2 (p=0.007) and on patient age ≥ 60 years (p=0.039). Conclusion Patient age greater than 60 years, Fuhrman grade ≥ 3, and tumor stage ≥ pT2 are independent risk factors of recurrence more than 5 years after surgery in patients with RCC. Therefore, close lifelong follow-up is recommended for patients with these risk factors.

Cross-Cultural Application of the Korean Version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire for Patients with Prostate Cancer - EORTC QLQ-PR25

Objective: We evaluated the psychometric properties of the Korean version of the European Organization for Research and Treatment of Cancer QLQ-PR25 when applied to Korean prostate cancer (PC) patients. Methods: A total of 172 patients who underwent curative radical prostatectomy (RP) with or without adjuvant androgen deprivation therapy were asked to complete the Korean version of the EORTC QLQ-C30 and PR25 questionnaires 3 times (before and 3 and 6 months after RP). Psychometric evaluation of the questionnaire was conducted. Results: Multitrait scaling analysis showed satisfactory construct validity in most scales except for bowel symptoms and hormonal treatment-related symptoms. Internal consistency tested by Cronbachs α coefficient met the 0.70 criterion for the urinary symptom, sexual activity and sexual functioning scales at the all 3 time points. Known-group comparison analyses showed better quality-of-life (QOL) scores in patients with higher performance status, and higher hormonal treatment-related symptom scores in patients on hormonal treatment. Responsiveness to changes was in line with clinical implications over time after RP. Conclusions: Our results show that the EORTC QLQ-PR25 questionnaire has adequate levels in cross-cultural validity. The Korean version of the EORTC QLQ-PR25 is a generally reliable and robust instrument for the assessment of various QOL aspects that can be self-administered to Korean PC patients undergoing RP.