Long short-term memory artificial neural network model for prediction of prostate cancer survival outcomes according to initial treatment strategy: development of an online decision-making support system.

PURPOSE: The delivery of precision medicine is a primary objective for both clinical and translational investigators. Patients with newly diagnosed prostate cancer (PCa) face the challenge of deciding among multiple initial treatment modalities. The purpose of this study is to utilize artificial neural network (ANN) modeling to predict survival outcomes according to initial treatment modality and to develop an online decision-making support system. METHODS: Data were collected retrospectively from 7267 patients diagnosed with PCa between January 1988 and December 2017. The analyses included 19 pretreatment clinicopathological covariates. Multilayer perceptron (MLP), MLP for N-year survival prediction (MLP-N), and long short-term memory (LSTM) ANN models were used to analyze progression to castration-resistant PCa (CRPC)-free survival, cancer-specific survival (CSS), and overall survival (OS), according to initial treatment modality. The performances of the ANN and the Cox-proportional hazards regression models were compared using Harrell's C-index. RESULTS: The ANN models provided higher predictive power for 5- and 10-year progression to CRPC-free survival, CSS, and OS compared to the Cox-proportional hazards regression model. The LSTM model achieved the highest predictive power, followed by the MLP-N, and MLP models. We developed an online decision-making support system based on the LSTM model to provide individualized survival outcomes at 5 and 10 years, according to the initial treatment strategy. CONCLUSION: The LSTM ANN model may provide individualized survival outcomes of PCa according to initial treatment strategy. Our online decision-making support system can be utilized by patients and health-care providers to determine the optimal initial treatment modality and to guide survival predictions.

Usage and perceptions of phosphodiesterase type 5 inhibitors among the male partners of infertile couples.

OBJECTIVE: We aimed to investigate the prevalence of erectile dysfunction (ED) and the usage of phosphodiesterase type 5 (PDE5) inhibitors for ED treatment in infertile couples. METHODS: A total of 260 male partners in couples reporting infertility lasting at least 1 year were included in this study. In addition to an evaluation of infertility, all participants completed the International Index of Erectile Function (IIEF)-5 questionnaire to evaluate their sexual function. The participants were asked about their use of PDE5 inhibitors while trying to conceive during their partner's ovulatory period and about their concerns regarding the risks of PDE5 inhibitor use to any eventual pregnancy and/or the fetus. RESULTS: Based on the IIEF-5 questionnaire, 41.5% of the participants (108/260) were classified as having mild ED (an IIEF-5 score of 17-21), while 10.4% of the participants (27/260) had greater than mild ED (an IIEF-5 score of 16 or less). The majority (74.2%, 193/260) of male partners of infertile couples had a negative perception of the safety of using a PDE5 inhibitor while trying to conceive. Only 11.1% of men (15/135) with ED in infertile couples had used a PDE5 inhibitor when attempting conception. CONCLUSION: ED was found to be common in the male partners of infertile couples, but the use of PDE5 inhibitors among these men was found to be very low. The majority of male partners were concerned about the risks of using PDE5 inhibitors when attempting to conceive. Appropriate counseling about this topic and treatment when necessary would likely be beneficial to infertile couples in which the male partner has ED.

Oncological outcomes after partial vs radical nephrectomy in renal cell carcinomas of ≤7 cm with presumed renal sinus fat invasion on preoperative imaging.

OBJECTIVES: To compare oncological outcomes of partial nephrectomy (PN) and radical nephrectomy (RN) for renal tumours of ≤7 cm in which preoperative imaging reveals potential renal sinus fat invasion (cT3a), as RN is preferred for these tumours due to concerns about high tumour stage. PATIENTS AND METHODS: Among 1137 nephrectomies performed for renal tumours of ≤7 cm from January 2005 to August 2012, 401 solitary cT3a renal cell carcinomas (RCCs) without metastases were analysed. Classification as cT3a included only renal sinus fat invasion, as there were no tumours with suspected perinephric fat invasion. Multivariate models were used to evaluate predictors of recurrence-free survival (RFS) and cancer-specific survival (CSS). RESULTS: There were 34 RCCs (8.5%) with unexpected perinephric fat invasion, but only 77 RCCs (19.2%) were staged as pT3a. During the median follow-up of 43.0 months, recurrence occurred in seven (6.7%) PN cases and 25 (8.4%) RN cases. Six recurred PN cases had positive surgical margins (PSMs). The two cohorts showed equal oncological outcomes for 5-year RFS and CSS. Multivariate analyses showed PSM, pathological T stage, sarcomatoid dedifferentiation, and type of surgery as significant predictors of recurrence. Older age, pathological T stage, and sarcomatoid dedifferentiation were significant predictors of cancer-specific mortality. CONCLUSIONS: Renal tumours of ≤7 cm with presumed renal sinus fat invasion were mostly pT1. PN conferred equivalent oncological outcomes to RN. If clear surgical margins can be obtained, PN should be considered for these tumours, as patients may benefit from renal function preservation.

Renoprotective Mechanism of Remote Ischemic Preconditioning Based on Transcriptomic Analysis in a Porcine Renal Ischemia Reperfusion Injury Model.

Ischemic preconditioning (IPC) is a well-known phenomenon in which tissues are exposed to a brief period of ischemia prior to a longer ischemic event. This technique produces tissue tolerance to ischemia reperfusion injury (IRI). Currently, IPC's mechanism of action is poorly understood. Using a porcine single kidney model, we performed remote IPC with renal IRI and evaluated the IPC mechanism of action. Following left nephrectomy, 15 female Yorkshire pigs were divided into three groups: no IPC and 90 minutes of warm ischemia (control), remote IPC immediately followed by 90 minutes of warm ischemia (rIPCe), and remote IPC with 90 minutes of warm ischemia performed 24 hours later (rIPCl). Differential gene expression analysis was performed using a porcine-specific microarray. The microarray analysis of porcine renal tissues identified 1,053 differentially expressed probes in preconditioned pigs. Among these, 179 genes had altered expression in both the rIPCe and rIPCl groups. The genes were largely related to oxidation reduction, apoptosis, and inflammatory response. In the rIPCl group, an additional 848 genes had altered expression levels. These genes were primarily related to immune response and inflammation, including those coding for cytokines and cytokine receptors and those that play roles in the complement system and coagulation cascade. In the complement system, the membrane attack complex was determined to be sublytic, because it colocalized with phosphorylated extracellular signal-regulated kinase. Furthermore, alpha 2 macroglobulin, tissue plasminogen activator, uterine plasmin trypsin inhibitor, and arginase-1 mRNA levels were elevated in the rIPCl group. These findings indicate that remote IPC produces renoprotective effects through multiple mechanisms, and these effects develop over a long timeframe rather than immediately following IPC.

Prognostic Impacts of Metastatic Site and Pain on Progression to Castrate Resistance and Mortality in Patients with Metastatic Prostate Cancer.

PURPOSE: To investigate predictors of progression to castration-resistant prostate cancer (CRPC) and cancer-specific mortality (CSM) in patients with metastatic prostate cancer (mPCa). MATERIALS AND METHODS: A retrospective analysis was performed on 440 consecutive treatment-naïve patients initially diagnosed with mPCa between August 2000 and June 2012. Patient age, body mass index (BMI), Gleason score, prostate-specific antigen (PSA), PSA nadir, American Joint Committee on Cancer stage, Visual Analogue Scale pain score, Eastern Cooperative Oncology Group performance score (ECOG PS), PSA response to hormone therapy, and metastatic sites were assessed. Cox-proportional hazards regression analyses were used to evaluate survivals and predictive variables of men with bone metastasis stratified according to the presence of pain, compared to men with visceral metastasis. RESULTS: Metastases were most often found in bone (75.4%), followed by lung (16.3%) and liver (8.3%) tissues. Bone metastasis, pain, and high BMI were associated with increased risks of progression to CRPC, and bone metastasis, pain, PSA nadir, and ECOG PS≥1 were significant predictors of CSM. During the median follow-up of 32.0 (interquartile range 14.7-55.9) months, patients with bone metastasis with pain and patients with both bone and visceral metastases showed the worst median progression to CRPC-free and cancer-specific survivals, followed by men with bone metastasis without pain. Patients with visceral metastasis had the best median survivals. CONCLUSION: Metastatic spread and pain patterns confer different prognosis in patients with mPCa. Bone may serve as a crucial microenvironment in the development of CRPC and disease progression.

Predictors of survival in prostate cancer patients with bone metastasis and extremely high prostate-specific antigen levels.

PURPOSE: Prostate-specific antigen (PSA) is a surrogate marker of disease progression; however, its predictive ability in the extreme ranges is unknown. We determined the predictors of survival in patients with bone metastatic prostate cancer (BMPCa) and with extremely high PSA levels. METHODS: Treatment-naïve patients (n = 248) diagnosed with BMPCa between December 2002 and June 2012 were retrospectively analyzed. Clinicopathological features at diagnosis, namely age, body mass index, serum alkaline phosphatase (ALP) and PSA levels, PSA nadir, time to PSA nadir and its maintenance period, PSA declining velocity, Gleason grade, clinical T stage, pain score, Eastern Cooperative Oncology Group performance score (ECOG PS), and the number of bone metastases were assessed. The patients were stratified according to PSA ranges of <20 ng/mL, 20-100 ng/mL, 100-1000 ng/mL, and 1000-10,000 ng/mL. Study endpoints were castration-resistant PCa (CRPC)-free survival and cancer-specific survival (CSS). RESULTS: Patients with higher PSA and ALP levels showed more bone lesions (P < 0.001). During the follow-up period (median, 39.9 months; interquartile range, 21.5-65.9 months), there were no differences between the groups in terms of the survival endpoints. High ALP levels, shorter time to PSA nadir, and pain were associated with an increased risk of progression to CRPC, and high ALP levels, ECOG PS ≥ 1, and higher PSA nadir independently predicted CSS. CONCLUSIONS: PSA response to androgen deprivation therapy and serum ALP are reliable predictors of survival in patients with BMPCa presenting with extremely high PSA levels. These patients should not be deterred from active treatment based on baseline PSA values.

Transurethral resection of the prostate for patients with Gleason score 6 prostate cancer and symptomatic prostatic enlargement: a risk-adaptive strategy for the era of active surveillance.

OBJECTIVE: To investigate whether transurethral resection of the prostate can be used as both (i) treatment for symptomatic prostatic enlargement in patients with prostate cancer and (ii) a risk-adaptive strategy for reducing prostate-specific antigen levels and broadening the indications of active surveillance. METHODS: We retrospectively reviewed data of 3680 patients who underwent prostate biopsies at a single institution (March 2006 to January 2012). Of 529 men who had Gleason score 6 prostate cancer and were ineligible for active surveillance, 86 (16.3%) underwent transurethral resection of the prostate for symptomatic prostatic enlargement. We assessed how changes in prostate-specific antigen and prostate-specific antigen density influenced the eligibility for active surveillance and the outcome of subsequent therapy. The following active surveillance criteria were used: prostate-specific antigen ≤ 10 ng/ml, prostate-specific antigen density ≤ 0.15, positive cores ≤ 3 and single core involvement ≤ 50%. RESULTS: The median age, pre-operative prostate-specific antigen and prostate volume were 71 years, 6.95 ng/ml, and 45.8 g, respectively. In 82.6% (71/86) of analyzed cases, ineligibility for active surveillance had resulted from elevated prostate-specific antigen level or prostate-specific antigen density. With a median resection of 16.5 g, transurethral resection of the prostate reduced the percentage of prostate-specific antigen and the percentage of prostate-specific antigen density by 34.5 and 50.0%, respectively, making 81.7% (58/71) of the patients eligible for active surveillance. Prostate-specific antigen level remained stabilized in all (21/21) patients maintained on active surveillance without disease progression during the median follow-up of 50.6 months. Among patients who underwent radical prostatectomy, 96.7% (29/30) exhibited localized disease. CONCLUSIONS: Risk-adaptive transurethral resection of the prostate may prevent overtreatment and allay prostate-specific antigen-associated anxiety in patients with biopsy-proven low-grade prostate cancer and elevated prostate-specific antigen. Additional benefits include voiding symptom improvement and the avoidance of curative therapy's immediate side effects.

Preconditioning strategies for kidney ischemia reperfusion injury: implications of the "time-window" in remote ischemic preconditioning.

Remote ischemic preconditioning (IP) is a potential renoprotective strategy. However, there has been no demonstrated result in large animals and the role of time window in remote IP remains to be defined. Using a single-kidney porcine model, we evaluated organ protective function of remote IP in renal ischemia reperfusion injury. Fifteen Yorkshire pigs, 20 weeks old and weighing 35-38 kg were used. One week after left nephrectomy, we performed remote IP (clamping right external iliac artery, 2 cycles of 10 minutes) and right renal artery clamping (warm ischemia; 90 minutes). The animals were randomly divided into three groups: control group, warm ischemia without IP; group 1 (remote IP with early window [IP-E]), IP followed by warm ischemia with a 10-minute time window; and group 2 (remote IP with late window [IP-L]), IP followed by warm ischemia after a 24-hour time window. There were no differences in serum creatinine changes between groups. The IP-L group had lower urinary neutrophil gelatinase-associated lipocalin than control and IP-E at 72 hours post-ischemia. At 72 hours post-ischemia, the urinary kidney injury molecule-1 (KIM-1) was lower in the IP-L group than in the control and IP-E groups, and the IP-L group KIM-1 was near pre-ischemic levels, whereas the control and IP-E group KIM-1 levels were rising. Microalbumin also tended to be lower in the IP-L group. Taken together, remote IP showed a significant reduction in renal injury biomarkers from ischemia reperfusion injury. To effectively provide kidney protection, remote IP might require a considerable, rather than short, time window of ischemia.

Impact of adjuvant chemotherapy in patients with upper tract urothelial carcinoma and lymphovascular invasion after radical nephroureterectomy.

PURPOSE: To evaluate the impact of adjuvant chemotherapy (AC) in patients with upper tract urothelial carcinoma and lymphovascular invasion (LVI) after radical nephroureterectomy (RNU). MATERIALS AND METHODS: We retrospectively analyzed the clinical records and clinicopatholgic outcomes of patients (n=552) treated with RNU between 1986 and 2013. Patients treated with neoadjuvant chemotherapy and those for whom LVI status was not recorded were excluded. Patients were divided into two groups according to LVI (n=86) or no LVI (n=256). RESULTS: The study included 344 patients (240 men and 104 women) with a median of 53.9 months of follow-up (range, 1-297 months) after RNU. Tumors were organ confined (T2/N0) in 211 (61.3%) and tumor grade high in 291 (84.6%). AC was administered in 64 patients (18.6%). A total of 280 patients (81.4%) were treated with surgery alone. Patients with LVI tended to be older (p=0.049), have a higher pT stage (pT3/T4, p<0.001), be pN+ (p<0.001), have a high tumor grade (p<0.001), and experience recurrence (p<0.001). In the multivariate analysis, LVI was an independent prognostic factor for cancer-specific survival and overall survival (p=0.002 and p<0.001, respectively). The multivariate analysis demonstrated that in the subgroup of patients with LVI, AC was a significant prognostic factor for cancer-specific survival and overall survival (hazard ratio, 0.51; p=0.027 and hazard ratio, 0.50; p=0.025, respectively). CONCLUSIONS: AC does not seem to reduce mortality in patients with advanced upper tract urothelial carcinoma after RNU. In the subgroup of patients with LVI, AC had a positive impact on cancer-specific survival and overall survival. LVI would be helpful for selecting patients who are appropriate for AC.

Prognostic impact of synchronous second primary malignancies on the overall survival of patients with metastatic prostate cancer.

PURPOSE: We determined the prognostic impact of a synchronous second primary malignancy on overall survival in patients with metastatic prostate cancer. Identifying features that stratify the risk of overall survival is critical for judiciously applying definitive therapy. MATERIALS AND METHODS: We retrospectively analyzed the records of 582 consecutive patients with prostate cancer diagnosed with metastasis between May 7, 1998 and August 27, 2011. Patient age, body mass index, ECOG performance status, Charlson comorbidity index, prostate specific antigen, T and N stages, Gleason and ASA® scores, progression to castration resistant prostate cancer, prior local treatments and synchronous second primary malignancies at metastasis were assessed. A synchronous second primary malignancy was defined as a cytologically or histologically proven solid malignancy. Cox proportional hazards regression analysis was done to estimate overall survival by second primary type and evaluate predictive variables. RESULTS: A total of 164 patients (28.1%) had a synchronous second primary malignancy, of which colorectal (9.1%), stomach (7.3%) and lung (7.1%) cancers were the most prevalent types. During a median followup of 34.1 months patients without a synchronous second primary malignancy had a significantly higher overall survival rate than those with lung or stomach cancer. However, men without a second malignancy had outcomes comparable to those in men with colorectal cancer. Clinical stage T4 or greater, ASA score 1 or greater and lung or stomach cancer were independent predictors of overall mortality. CONCLUSIONS: A substantial proportion of patients with metastatic prostate cancer present with a synchronous second primary malignancy. Definitive therapy targeting prostate cancer may confer a limited survival benefit in patients with synchronous lung or stomach cancer.

Adjuvant radiotherapy outcome of stage I testicular seminoma: a single institution study.

PURPOSE: To analyze treatment outcome and side effects of adjuvant radiotherapy using radiotherapy fields and doses which have evolved over the last two decades in a single institution. MATERIALS AND METHODS: Forty-one patients received radiotherapy after orchiectomy from 1996 to 2007. At our institution, the treatment field for stage I seminoma has changed from dog-leg (DL) field prior to 2003 to paraaortic (PA) field after 2003. Fifteen patients were treated with the classic fractionation scheme of 25.5 Gy at 1.5 Gy per fraction. Other patients had been treated with modified schedules of 25.05 Gy at 1.67 Gy per fraction (n=15) and 25.2 Gy at 1.8 Gy per fraction (n=11). RESULTS: With a median follow-up of 112 months, the 5-year and 10-year survival rates were 100% and 96%, respectively, and 5-year and 10-year relapse-free survival rates were both 97.1%. No in-field recurrence occurred. Contralateral seminoma occurred in one patient 5 years after treatment. No grade III-IV acute toxicity occurred. An increased rate of grade 1-2 acute hematologic toxicity was found in patients with longer overall treatment times due to 1.5 Gy per fraction. The rate of grade 2 acute gastrointestinal toxicity was significantly higher with DL field than with PA field and also higher in the 1.8-Gy group than in the 1.5-Gy and 1.67-Gy groups. CONCLUSION: Patients with stage I seminoma were safely treated with PA-only radiotherapy with no pelvic failure. Optimal fractionation schedule needs to be explored further in order to minimize treatment-related toxicity.

Treatment outcome of localized prostate cancer by 70 Gy hypofractionated intensity-modulated radiotherapy with a customized rectal balloon.

PURPOSE: We aimed to analyze the treatment outcome and long-term toxicity of 70 Gy hypofractionated intensity-modulated radiotherapy (IMRT) for localized prostate cancer using a customized rectal balloon. MATERIALS AND METHODS: We reviewed medical records of 86 prostate cancer patients who received curative radiotherapy between January 2004 and December 2011 at our institution. Patients were designated as low (12.8%), intermediate (20.9%), or high risk (66.3%). Thirty patients received a total dose of 70 Gy in 28 fractions over 5 weeks via IMRT (the Hypo-IMRT group); 56 received 70.2 Gy in 39 fractions over 7 weeks via 3-dimensional conformal radiotherapy (the CF-3DRT group, which served as a reference for comparison). A customized rectal balloon was placed in Hypo-IMRT group throughout the entire radiotherapy course. Androgen deprivation therapy was administered to 47 patients (Hypo-IMRT group, 17; CF-3DRT group, 30). Late genitourinary (GU) and gastrointestinal (GI) toxicity were evaluated according to the Radiation Therapy Oncology Group criteria. RESULTS: The median follow-up period was 74.4 months (range, 18.8 to 125.9 months). The 5-year actuarial biochemical relapse-free survival rates for low-, intermediate-, and high-risk patients were 100%, 100%, and 88.5%, respectively, for the Hypo-IMRT group and 80%, 77.8%, and 63.6%, respectively, for the CF-3DRT group (p < 0.046). No patient presented with acute or late GU toxicity ≥grade 3. Late grade 3 GI toxicity occurred in 2 patients (3.6%) in the CF-3DRT group and 1 patient (3.3%) in the Hypo-IMRT group. CONCLUSION: Hypo-IMRT with a customized rectal balloon resulted in excellent biochemical control rates with minimal toxicity in localized prostate cancer patients.

Prognostic factors for urachal cancer: a bayesian model-averaging approach.

PURPOSE: This study was conducted to evaluate prognostic factors and cancer-specific survival (CSS) in a cohort of 41 patients with urachal carcinoma by use of a Bayesian model-averaging approach. MATERIALS AND METHODS: Our cohort included 41 patients with urachal carcinoma who underwent extended partial cystectomy, total cystectomy, transurethral resection, chemotherapy, or radiotherapy at a single institute. All patients were classified by both the Sheldon and the Mayo staging systems according to histopathologic reports and preoperative radiologic findings. Kaplan-Meier survival curves and Cox proportional-hazards regression models were carried out to investigate prognostic factors, and a Bayesian model-averaging approach was performed to confirm the significance of each variable by using posterior probabilities. RESULTS: The mean age of the patients was 49.88 ± 13.80 years and the male-to-female ratio was 24:17. The median follow-up was 5.42 years (interquartile range, 2.8-8.4 years). Five- and 10-year CSS rates were 55.9% and 43.4%, respectively. Lower Sheldon (p=0.004) and Mayo (p<0.001) stage, mucinous adenocarcinoma (p=0.005), and larger tumor size (p=0.023) were significant predictors of high survival probability on the basis of a log-rank test. By use of the Bayesian model-averaging approach, higher Mayo stage and larger tumor size were significant predictors of cancer-specific mortality in urachal carcinoma. CONCLUSIONS: The Mayo staging system might be more effective than the Sheldon staging system. In addition, the multivariate analyses suggested that tumor size may be a prognostic factor for urachal carcinoma.

Graft survival after video-assisted minilaparotomy living-donor nephrectomy or conventional open nephrectomy: do left and right allografts differ?

OBJECTIVE: To examine the effect of the side of the allograft (left vs right) on early graft failure and long-term graft survival rates after conventional open living-donor nephrectomy (OLDN) or video-assisted minilaparotomy living-donor nephrectomy (VLDN). MATERIALS AND METHODS: We evaluated 2704 living-donor transplantations using OLDN or VLDN between 1991 and 2011 at a single institution. For analysis, the entire period was divided into "era 1" (1991-1997), when OLDN was prevalent; "era 2" (1998-2004), when both OLDN and VLDN were conducted; and "era 3" (2005-2011), when VLDN became prevalent. RESULTS: There were 822, 650, and 685 transplantations analyzed in eras 1, 2, and 3, respectively. There were no differences in causes of early graft failure between left and right allografts in any era. The right allograft survival rate in eras 1 and 2 was slightly lower than the left allograft survival rate. In era 2, during which both OLDN and VLDN were conducted, Kaplan-Meier analysis showed lower right allograft survival rate for OLDN. However, the long-term survival rates of the left and right VLDN grafts did not differ. CONCLUSION: Right OLDN allografts demonstrated worse long-term survival rate than left OLDN allografts, but the right and left VLDN allografts had similar long-term survival rate. VLDN appears to be an appropriate treatment option when right donor nephrectomy is desired.

Low body mass index is associated with adverse oncological outcomes following radical prostatectomy in Korean prostate cancer patients.

PURPOSE: The purpose of this study was to determine the impact of obesity on clinicopathological features and biochemical recurrence (BCR) following radical prostatectomy (RP) in Korean prostate cancer (PCa) patients. METHODS: A single-institutional retrospective analysis was performed on 880 PCa patients treated by RP without neoadjuvant therapy between July 2005 and December 2011. Patients were stratified according to body mass index (BMI) standards for Asian populations: obese (BMI ≥25 kg/m(2)), overweight (BMI 23-24.9 kg/m(2)), or normal weight (BMI <23 kg/m(2)). For analysis, overweight and obese patients were combined (n = 592, BMI ≥23 kg/m(2)) and compared with normal weight patients (n = 288, BMI <23 kg/m(2)). BCR was defined as prostate-specific antigen (PSA) ≥0.2 ng/ml following RP. RESULTS: Normal weight patients tended to be classified into the higher D'Amico risk category with smaller prostate volumes compared with obese and overweight patients. Normal weight patients had higher pathological Gleason scores and were at higher risk of BCR during the mean follow-up of 58.2 months. This translated to a higher 5-year BCR-free survival rate for obese and overweight patients compared with normal weight patients (77.8 vs. 70.3 %; p = 0.017). On multiple Cox-proportional hazards regression analysis incorporating variables of BMI category, PSA, positive surgical margins, pathological T stage, and Gleason score, higher BMI category remained a significant predictor of a lower risk of BCR (HR = 0.634, p = 0.028). CONCLUSIONS: Obese and overweight Korean PCa patients have lower Gleason scores and a reduced risk of BCR compared with normal weight patients. These findings suggest that body fat influences pathological features and oncologic outcomes of PCa.

Prospective measurement of urinary microalbumin in living kidney donor nephrectomy: toward understanding the renal functional recovery period.

PURPOSE: We determined the clinical implications of perioperative urinary microalbumin excretion in relation to renal function after living donor nephrectomy. MATERIALS AND METHODS: Between August 2010 and January 2013, 259 donors undergoing live donor nephrectomy were enrolled in the study. The donor urinary albumin-to-creatinine ratio was measured perioperatively, and changes in perioperative urinary albumin-to-creatinine ratio and the implications of preoperative microalbuminuria (urinary albumin-to-creatinine ratio 30 mg/gm or greater) were investigated. The relationships between perioperative urinary albumin-to-creatinine ratio and recovery of renal function and implantation biopsy histology were also analyzed. RESULTS: Mean ± SD preoperative urinary albumin-to-creatinine ratio was 7.1±12.7 mg/gm. The urinary albumin-to-creatinine ratio was increased after 1 day (24.7±18.9 mg/gm, p <0.001) and stabilized after 1 month (10.3±10.7 mg/gm, p <0.001). Preoperative microalbuminuria was not associated with perioperative estimated glomerular filtration rate during a followup period of 6 months but was associated with histological abnormalities. Donors with a higher urinary albumin-to-creatinine ratio before donation, even in the normal range, consistently had an increased postoperative urinary albumin-to-creatinine ratio. A ROC curve analysis showed that age, preoperative estimated glomerular filtration rate and 1-month postoperative urinary albumin-to-creatinine ratio were highly predictive of delayed recovery of renal function (AUC 0.884, p <0.001). The 1-month postoperative urinary albumin-to-creatinine ratio was associated with delayed recovery of renal function (OR 1.05 for each 0.1 mg/gm increase, p=0.021). CONCLUSIONS: Donors with higher preoperative urinary albumin-to-creatinine ratio levels require close observation because there is a greater possibility of microalbuminuria developing after donation even if the ratio is within the normal range. A higher urinary albumin-to-creatinine ratio was also associated with delayed recovery of renal function and histological abnormalities.

Robot-assisted radical prostatectomy in the Korean population: a 5-year propensity-score matched comparative analysis versus open radical prostatectomy.

OBJECTIVES: To compare the oncological outcomes of robot-assisted laparoscopic radical prostatectomy with those of open radical prostatectomy in contemporary Korean prostate cancer patients. METHODS: From a group of 1172 patients consisting of 592 (50.5%) robot-assisted laparoscopic radical prostatectomy and 580 (49.5%) open radical prostatectomy cases carried out between 1992 and 2008, 175 robot-assisted laparoscopic radical prostatectomy cases were matched with an equal number of open radical prostatectomy cases by propensity scoring based on patient age, preoperative prostate-specific antigen, biopsy Gleason score and clinical tumor stage. Competing-risks survival analyses were used to evaluate oncological outcomes, including rates of positive surgical margin, biochemical-recurrence, adjuvant therapy, cancer-specific survival, overall survival and metastasis-free survival during the mean follow up of 58.4 months. RESULTS: Positive surgical margin rates were comparable between robot-assisted laparoscopic radical prostatectomy and open radical prostatectomy cohorts (19.4% vs 21.8%), with comparable rates for all pathological stages and risk subgroups. Positive surgical margin rates according to location were comparable, with the apical margin being the most common location. Robot-assisted laparoscopic radical prostatectomy recovered higher lymph node yields compared with open radical prostatectomy (12.5 vs 3.8; P < 0.001). The robot-assisted laparoscopic radical prostatectomy and the open radical prostatectomy groups showed equal oncological outcomes regarding 5-year biochemical recurrence-free survival (log-rank P = 0.651), metastasis-free survival (log-rank P = 0.876), cancer-specific survival (log-rank P = 0.076) and overall survival (log-rank P = 0.648), respectively. Between groups, there was no difference in the rate of adjuvant therapy, time to first adjuvant therapy failure or in the rate of subsequent secondary treatment. CONCLUSIONS: Robot-assisted laparoscopic radical prostatectomy represents an effective surgical approach for the treatment of prostate cancer in the Korean population, as it provides equivalent oncological outcomes to open radical prostatectomy.

Charlson comorbidity index is an important prognostic factor for long-term survival outcomes in Korean men with prostate cancer after radical prostatectomy.

PURPOSE: To analyze overall survival (OS), prostate cancer (PCa)-specific survival (PCaSS), and non-PCaSS according to the Charlson Comorbidity Index (CCI) after radical prostatectomy (RP) for PCa. MATERIALS AND METHODS: Data from 336 patients who had RP for PCa between 1992 and 2005 were analyzed. Data included age, preoperative prostate-specific antigen (PSA), prostate volume, clinical stage, and pathologic stage. Pre-existing comorbidities were evaluated by the CCI, and patients were classified into two CCI score categories (0, ≥1). RESULTS: The mean age of patients was 64.31±6.12 years. The median PSA value (interquartile range, IQR) was 11.30 (7.35 and 21.02) ng/mL with a median follow-up period (IQR) of 96.0 (85.0 and 121.0) months. The mean CCI was 0.28 (0-4). Five-year OS, PCaSS, and non-PCaSS were 91.7%, 96.3%, and 95.2%, respectively. Ten-year OS, PCaSS, and non-PCaSS were 81.9%, 92.1%, and 88.9%, respectively. The CCI had a significant influence on OS (p=0.022) and non-PCaSS (p=0.008), but not on PCaSS (p=0.681), by log-rank test. In multivariate Cox regression analysis, OS was independently associated with the CCI [hazard ratio (HR)=1.907, p=0.025] and Gleason score (HR=2.656, p<0.001). PCaSS was independently associated with pathologic N stage (HR=2.857, p=0.031), pathologic T stage (HR=3.775, p=0.041), and Gleason score (HR=4.308, p=0.001). Non-PCaSS had a significant association only with the CCI (HR=2.540, p=0.009). CONCLUSION: The CCI was independently associated with both OS and non-PCaSS after RP, but the CCI had no impact on PCaSS. The comorbidities of a patient should be considered before selecting RP as a curative modality for PCa.

Impact of Charlson comorbidity index varies by age in patients with prostate cancer treated by radical prostatectomy: a competing risk regression analysis.

PURPOSE: To investigate the prognostic impact of the Charlson comorbidity index (CCI) on either cancer-specific mortality (CSM) or other-cause mortality (OCM) according to age in patients with prostate cancer (PC) who underwent radical prostatectomy (RP). METHODS: Data from 336 patients who underwent RP for PC between 1992 and 2005 were analyzed. Variables, including the preoperative prostate-specific antigen (PSA), prostate volume, clinical stage, and pathologic stage, were compared across age groups (<65 or ≥65 years old). Preexisting comorbidities were evaluated by the CCI, and patients were classified into two CCI score categories (0 or ≥1). RESULTS: The median (interquartile range) follow-up period was 96 (85-121) months. Subjects were divided into two subgroups according to age: <65 years (n = 151) or ≥65 years (n = 185). There was no significant difference in PSA, biopsy Gleason sum, body mass index, pathologic stage, or CCI between the two age groups. OCM was significantly associated with the CCI score (P = 0.011). Cumulative incidence estimates obtained from competing risk regression analysis indicated that CCI was not associated with CSM (P = 0.795) or OCM (P = 0.123) in the ≥65-year group. However, in men <65 years, cumulative incidence estimates for OCM were significantly associated with CCI (P = 0.036). CONCLUSIONS: CCI was independently associated with OCM after RP, but only in men <65 years old. CCI was not associated with CSM in either age group. Accordingly, a thorough evaluation of patient's comorbidities is mandatory when considering aggressive surgical treatment, especially in relatively young patients.

Clinical implications for graft function of a new equation model for the ratio of living donor kidney volume to recipient body surface area.

PURPOSE: We propose an equation that predicts graft function after kidney transplantation by using donated kidney volume and recipient body surface area (BSA). MATERIALS AND METHODS: Included were 261 cases of living kidney transplantation between 2007 and 2009. Preoperative computed tomography scans were performed and the donated kidney volume was measured by use of a three-dimensional reconstruction program (Ripidia). The estimated glomerular filtration rate (eGFR) was calculated by using the modification of diet in renal disease formula. Donated kidney volume, preoperative renal function, and demographic factors of both donors and recipients were evaluated as predictors. RESULTS: The mean ages of the donors and recipients were 40.8 and 41.6 years, respectively. The mean donated kidney volume and donated kidney volume/recipient BSA ratio were 153.4 mL and 96.9 mL/m(2), respectively. Mean preoperative and postoperative 12-month eGFR of recipients were 7.1 and 59.7 mL/min, respectively, and the mean preoperative eGFR of donors was 92.2 mL/min. Donated kidney volume/recipient BSA ratio, donor age, and recipient gender were the significant predictors of eGFR level (p<0.001) and eGFR<45 mL/min at postoperative 12 months (p=0.005, p<0.001, and p=0.006). From the multiple linear regression equation and predicted probability from logistic regression, we could calculate the equation for the ratio of living donor kidney volume to recipient BSA on graft function. CONCLUSIONS: Graft kidney volume/recipient BSA ratio, donor age, and recipient gender were predictors of graft function 12 months after kidney transplantation. Although we are concerned only with the preoperative, this equation model could help physicians to counsel patients concerning their postoperative prognosis and to avoid insufficient volume donations.