Bumsoo Park

Body mass index and survival in patients with renal cell carcinoma: a clinical-based cohort and meta-analysis.

Growing evidence suggests that obesity, an established cause of renal cell cancer (RCC), may also be associated with a better prognosis. To evaluate the association between RCC survival and obesity, we analyzed a large cohort of patients with RCC and undertook a meta‐analysis of the published evidence. We collected clinical and pathologic data from 1,543 patients who underwent nephrectomy for RCC between 1994 and 2008 with complete follow‐up through 2008. Patients were grouped according to BMI (kg/m2): underweight <18.5, normal weight 18.5 to <23, overweight 23 to <25 and obese ≥25. We estimated survival using the Kaplan–Meier method and Cox proportional hazard models to examine the impact of BMI on overall survival (OS) and cancer‐specific survival (CSS) with adjustment for covariates. We performed a meta‐analysis of BMI and OS, CSS and recurrence‐free survival (RFS) from all relevant studies using a random‐effects model. The 5‐year CSS increased from 76.1% in the lowest to 92.7% in the highest BMI category. A multivariate analysis showed higher OS [hazard ratio (HR) = 0.45; 95% CI: 0.29–0.68) and CSS (HR = 0.47; 95% CI: 0.29–0.77] in obese patients than in normal weight patients. The meta‐analysis further corroborated that high BMI significantly improved OS (HR = 0.57; 95% CI: 0.43–0.76), CSS (HR = 0.59; 95% CI: 0.48–0.74) and RFS (HR = 0.49; 95% CI: 0.30–0.81). Our study shows that preoperative BMI is an independent prognostic indicator for survival among patients with RCC.

Efficacy and Safety of a Novel, Double-Layered, Coated, Self-Expandable Metallic Mesh Stent (Uventa™) in Malignant Ureteral Obstructions

BACKGROUND AND PURPOSE Malignant ureteral obstruction (MUO) is a common condition and an intractable situation for patients with advanced cancer. There is currently no ideal ureteral stent to release the obstruction. Our purpose was to evaluate the clinical efficacy and safety of a novel, double-layered, coated, self-expandable metallic mesh stent (Uventa(™)) in MUO. PATIENTS AND METHODS In a retrospective design, a total of 71 ureter units (54 patients) were included from December 2009 to March 2012. Indications were those who had MUO with a polymeric Double-J stent malfunction, severe polymeric stent irritation, or severe pain during periodic stent change. Patients underwent Uventa placement using a retrograde approach. RESULTS All stents were positioned at the proper site without procedure-related complications. The overall success (no obstruction and no additional intervention except supplementary Uventa placement) and primary success (no obstruction and no additional intervention) rates were 81.7% (58/71 ureter units) and 64.8% (46/71 ureter units) during the follow-up period, which had a median of 308 (35-802) days. The most common reason for primary failure was tumor progression beyond the stent segment (75.0%), followed by reactive hyperplasia at the stent tips (12.5%), bladder invasion of the primary tumor (8.0%), and stent-related pain (8.0%). Twelve patients had overall success after secondary Uventa placement. There were no severe complications. The complications included persistent flank pain (15.5%), lower urinary tract symptoms (7.0%), acute pyelonephritis (2.8%), stent migration (2.8%), and persistent hematuria (2.8%). CONCLUSIONS These data show that Uventa can be an effective and safe option for palliative treatment of patients with MUO in a large series of patients.

Influence of Body Mass Index, Smoking, and Blood Pressure on Survival of Patients with Surgically-Treated, Low Stage Renal Cell Carcinoma: A 14-Year Retrospective Cohort Study

The association of body mass index, smoking, and blood pressure, which are related to the three well-established risk factors of renal cell carcinoma, and survival in patients with renal cell carcinoma is not much studied. Our objective was to evaluate this association. A cohort of 1,036 patients with low stage (pT1 and pT2) renal cell carcinoma who underwent radical or partial nephrectomy were enrolled. We retrospectively reviewed medical records and collected survival data. The body mass index, smoking status, and blood pressure at the time of surgery were recorded. Patients were grouped according to their obesity grade, smoking status, and hypertension stage. Survival analysis showed a significant decrease in overall (P = 0.001) and cancer-specific survival (P < 0.001) with being underweight, with no differences of smoking status or perioperative blood pressure. On multivariate analysis, perioperative blood pressure ≥ 160/100 mmHg (HR, 2.642; 95% CI, 1.221-5.720) and being underweight (HR, 4.320; 95% CI, 1.557-11.984) were independent predictors of overall and cancer-specific mortality, respectively. Therefore, it is concluded that being underweight and perioperative blood pressure ≥ 160/100 mmHg negatively affect cancer-specific and overall survival, respectively, while smoking status does not influence survivals in patients with renal cell carcinoma.

Development and characterization of a bladder cancer xenograft model using patient-derived tumor tissue

Most of the cancer xenograft models are derived from tumor cell lines, but they do not sufficiently represent clinical cancer characteristics. Our objective was to develop xenograft models of bladder cancer derived from human tumor tissue and characterize them molecularly as well as histologically. A total of 65 bladder cancer tissues were transplanted to immunodeficient mice. Passagable six cases with clinico‐pathologically heterogeneous bladder cancer were selected and their tumor tissues were collected (012T, 025T, 033T, 043T, 048T, and 052T). Xenografts were removed and processed for the following analyses: (i) histologic examination, (ii) short tandem repeat (STR) genotyping, (iii) mutational analysis, and (iv) array‐based comparative genomic hybridization (array‐CGH). The original tumor tissues (P 0) and xenografts of passage 2 or higher (≥P2) were analyzed and compared. As a result, hematoxylin and eosin staining revealed the same histologic architecture and degree of differentiation in the primary and xenograft tumors in all six cases. Xenograft models 043T_P2 and 048T_P2 had completely identical STR profiles to the original samples for all STR loci. The other models had nearly identical STR profiles. On mutational analysis, four out of six xenografts had mutations identical to the original samples for TP53, HRAS, BRAF, and CTNNB1. Array‐CGH analysis revealed that all six xenograft models had genomic alterations similar to the original tumor samples. In conclusion, our xenograft bladder cancer model derived from patient tumor tissue is expected to be useful for studying the heterogeneity of the tumor populations in bladder cancer and for evaluating new treatments.

Pure laparoscopic radical cystectomy with ileal conduit: a single surgeon's mid-term outcomes.

Purpose The use of laparoscopic radical cystectomy (LRC) for muscle-invasive bladder cancer is not yet widespread because of the technical difficulties of the procedure and the lengthy operating time. In this study, we report a single surgeons experience with LRC. Materials and Methods Thirty patients (25 men and 5 women) with bladder cancer underwent LRC and ileal conduit by a single surgeon between November 2007 and May 2011. An extracorporeal urinary diversion was performed through 5-6 cm midline incision for specimen extraction. Results The median operating time and estimated blood loss were 527.5 minutes and 275 mL, respectively. There was no conversion to open surgery. The median time to oral intake and postoperative hospital stay were 5 days and 12 days, respectively. The rates of immediate, early postoperative and late postoperative complication were 3.3%, 20% and 20%, respectively. With 16 months of median follow-up, the overall and recurrence-free survival rates were 70% and 56.7%, respectively. Conclusion LRC is feasible for the management of invasive bladder cancer and, with appropriate patient selection, can be a good alternative to open or robot-assisted radical cystectomy in the era of robot-assisted surgery.

Detection rate of clinically insignificant prostate cancer increases with repeat prostate biopsies

To analyze if clinically insignificant prostate cancer (CIPC) is more frequently detected with repeat prostate biopsies, we retrospectively analyzed the records of 2146 men diagnosed with prostate cancer after one or more prostate biopsies. The patients were divided into five groups according to the number of prostate biopsies obtained, e.g. group 1 had one biopsy, group 2 had two biopsies and group 3 had three biopsies. Of the 2146 patients diagnosed with prostate cancer, 1956 (91.1%), 142 (6.6%), 38 (1.8%), 9 (0.4%) and 1 (0.1%) men were in groups 1, 2, 3, 4 and 5, respectively. Groups 4 and 5 were excluded because of the small sample sizes. The remaining three groups (groups 1, 2 and 3) were statistically analyzed. There were no differences in age or prostate-specific antigen level among the three groups. CIPC was detected in 201 (10.3%), 28 (19.7%) and 9 (23.7%) patients in groups 1, 2 and 3, respectively (P<0.001). A multivariate analysis showed that the number of biopsies was an independent predictor to detect CIPC (OR=2.688 for group 2; OR=4.723 for group 3). In conclusion, patients undergoing multiple prostate biopsies are more likely to be diagnosed with CIPC than those who only undergo one biopsy. However, the risk still exists that the patient could have clinically significant prostate cancer. Therefore, when counseling patients with regard to serial repeat biopsies, the possibility of prostate cancer overdiagnosis and overtreatment must be balanced with the continued risk of clinically significant disease.

Interval from Prostate Biopsy to Radical Prostatectomy Does Not Affect Immediate Operative Outcomes for Open or Minimally Invasive Approach

Traditionally, urologists recommend an interval of at least 4 weeks after prostate biopsy before radical prostatectomy. The aim of our study was to evaluate whether the interval from prostate biopsy to radical prostatectomy affects immediate operative outcomes, with a focus on differences in surgical approach. The study population of 1,848 radical prostatectomy patients was divided into two groups according to the surgical approach: open or minimally invasive. Open group included perineal and retropubic approach, and minimally invasive group included laparoscopic and robotic approach. The cut-off of the biopsy-to-surgery interval was 4 weeks. Positive surgical margin status, operative time and estimated blood loss were evaluated as endpoint parameters. In the open group, there were significant differences in operative time and estimated blood loss between the <4-week and ≥4-week interval subgroups, but there was no difference in positive margin rate. In the minimally invasive group, there were no differences in the three outcome parameters between the two subgroups. Multivariate analysis revealed that the biopsy-to-surgery interval was not a significant factor affecting immediate operative outcomes in both open and minimally invasive groups, with the exception of the interval ≥4 weeks as a significant factor decreasing operative time in the minimally invasive group. In conclusion, performing open or minimally invasive radical prostatectomy within 4 weeks of prostate biopsy is feasible for both approaches, and is even beneficial for minimally invasive radical prostatectomy to reduce operative time. Graphical Abstract

V867 LAPAROSCOPIC ADRENALECTOMY STEP-BY-STEP SURGICAL SKILLS

Abstract Introduction and Objective: To introduce step-by-step skills and to show the learning curve of pure laparoscopic adrenalectomy performed by a single surgeon. Materials and Methods: From October 2008 to September 2011, 74 patients out of 112 who were diagnosed as adrenal mass received pure laparoscopic adrenalectomy. Eight cases were bilateral, and 66 cases were unilateral. After placing the patient in the flank position, a 12-mm camera port is inserted near umbilicus. Two 5-mm working ports are placed at the cross-sections of the midclavicle line, anterior axillary line, and subcostal margin. About 2-mm port for liver retraction is placed just below the xiphoid process if the mass is on the right side. When performing a right adrenalectomy, an avascular triangle formed by the vena cava, liver, and renal vein is identified. The adrenal gland is lifted up using a pair of forceps or suction, and adrenal vein is ligated. Inferior phrenic vascular supply at the liver margin and renal hilum vascular su...