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Featured researches published by Byong Chang Jeong.


European Urology | 2011

Laparoendoscopic Single-site Surgery in Urology: Worldwide Multi-institutional Analysis of 1076 Cases

Jihad H. Kaouk; Riccardo Autorino; Fernando J. Kim; Deok Hyun Han; Seung Wook Lee; Sun Yinghao; Jeffrey A. Cadeddu; Ithaar H. Derweesh; Lee Richstone; Luca Cindolo; Anibal Branco; Francesco Greco; Mohamad E. Allaf; Rene Sotelo; Evangelos Liatsikos; J.-U. Stolzenburg; Abhay Rane; Wesley M. White; Woong Kyu Han; Georges Pascal Haber; Michael A. White; Wilson R. Molina; Byong Chang Jeong; Joo Yong Lee; Wang Linhui; Sara Best; Sean P. Stroup; Soroush Rais-Bahrami; Luigi Schips; Paolo Fornara

BACKGROUND Laparoendoscopic single-site surgery (LESS) has gained popularity in urology over the last few years. OBJECTIVE To report a large multi-institutional worldwide series of LESS in urology. DESIGN, SETTING, AND PARTICIPANTS Consecutive cases of LESS done between August 2007 and November 2010 at 18 participating institutions were included in this retrospective analysis. INTERVENTION Each group performed a variety of LESS procedures according to its own protocols, entry criteria, and techniques. MEASUREMENTS Demographic data, main perioperative outcome parameters, and information related to the surgical technique were gathered and analyzed. Conversions to reduced-port laparoscopy, conventional laparoscopy, or open surgery were evaluated, as were intraoperative and postoperative complications. RESULTS AND LIMITATIONS Overall, 1076 patients were included in the analysis. The most common procedures were extirpative or ablative operations in the upper urinary tract. The da Vinci robot was used to operate on 143 patients (13%). A single-port technique was most commonly used and the umbilicus represented the most common access site. Overall, operative time was 160±93 min and estimated blood loss was 148±234 ml. Skin incision length at closure was 3.5±1.5 cm. Mean hospital stay was 3.6±2.7 d with a visual analog pain score at discharge of 1.5±1.4. An additional port was used in 23% of cases. The overall conversion rate was 20.8%; 15.8% of patients were converted to reduced-port laparoscopy, 4% to conventional laparoscopy/robotic surgery, and 1% to open surgery. The intraoperative complication rate was 3.3%. Postoperative complications, mostly low grade, were encountered in 9.5% of cases. CONCLUSIONS This study provides a global view of the evolution of LESS in the field of minimally invasive urologic surgery. A broad range of procedures have been effectively performed, primarily in the academic setting, within diverse health care systems around the world. Since LESS is performed by experienced laparoscopic surgeons, the risk of complications remains low when stringent patient-selection criteria are applied.


Journal of Endourology | 2009

Laparoendoscopic single-site and conventional laparoscopic adrenalectomy: a matched case-control study.

Byong Chang Jeong; Yong Hyun Park; Deok Hyun Han; Hyeon Hoe Kim

PURPOSE The purpose of this study was to describe our initial clinical experience and assess the feasibility of laparoendoscopic single-site surgery (LESS) in the treatment of benign adrenal adenoma. PATIENTS AND METHODS Nine patients undergoing LESS adrenalectomy for benign adrenal adenoma were compared with 17 patients undergoing conventional laparoscopic adrenalectomy. Controls were matched for age, sex, surgical indications, and tumor size via a statistically generated selection of all conventional laparoscopic adrenalectomies performed during the same period of time. RESULTS No significant differences in the mean operative time (169 vs. 144.5 minutes, p = 0.287), blood loss (177.8 vs. 204.7 mL, p = 0.792), and postoperative hospital stay (3.2 vs. 3.5 days, p = 0.525) were observed between the LESS and conventional laparoscopy group. However, postoperative pain, as measured by the number of days of intravenous (IV) patient controlled anesthesia use, was significantly lower in the LESS group (0.9 vs. 1.9 days, p = 0.047). Perioperative complications were similar between the two groups. CONCLUSIONS LESS adrenalectomy for benign adrenal adenoma is comparable to the conventional laparoscopic approach with regard to the operative time, blood loss, length of hospital stay, and degree of complication, and has demonstrated more desirable cosmetic outcomes.


International Journal of Cancer | 2013

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

Y.-K. Choi; Bumsoo Park; Byong Chang Jeong; Seong Il Seo; Seong Soo Jeon; Han Yong Choi; Hans-Olov Adami; Jung Eun Lee; Hyun Moo Lee

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.


American Journal of Roentgenology | 2011

Prospective evaluation of 3-T MRI performed before initial transrectal ultrasound-guided prostate biopsy in patients with high prostate-specific antigen and no previous biopsy.

Byung Kwan Park; Jong Wook Park; Seo Yong Park; Chan Kyo Kim; Hyun Moo Lee; Seong Soo Jeon; Seong Il Seo; Byong Chang Jeong; Han Yong Choi

OBJECTIVE The purpose of our study was to prospectively evaluate whether MRI before an initial transrectal ultrasound-guided biopsy contributed to detection of prostate cancer in patients with high prostate-specific antigen (PSA) level and no previous biopsy. SUBJECTS AND METHODS Men with an abnormal digital rectal examination or high PSA level were enrolled in this prospective randomized study. Participants were randomly allocated into two groups; the MRI group underwent 3-T MRI and then a transrectal ultrasound-guided biopsy with knowledge of the cancer location. The non-MRI group did not undergo MRI before transrectal ultrasound-guided biopsy. The cancer detection rate and positive core rate were obtained to compare the MRI and non-MRI groups. RESULTS The MRI and non-MRI groups contained 44 and 41 patients, respectively. There was no significant difference between the two groups with respect to age, PSA, and prostate volume. The MRI group (13/44, 29.5%) had a significantly higher cancer detection rate than the non-MRI group (4/41, 9.8%) (p = 0.03). The MRI group (52/527, 9.9%) had a significantly higher positive core rate than the non-MRI group (11/432, 2.5%) (p = 0.00). Regarding cancer detection rate and positive core rate, odds ratios were 3.9 (95% CI, 1.1-13.1) and 4.2 (95% CI, 2.2-8.1), respectively. CONCLUSION In patients with PSA level and no previous biopsy, 3-T MRI that is performed before transrectal ultrasound-guided biopsy may contribute to the detection of prostate cancer.


European Urology | 2010

Renal Damage Caused by Warm Ischaemia During Laparoscopic and Robot-Assisted Partial Nephrectomy: An Assessment Using Tc 99m-DTPA Glomerular Filtration Rate

Jae Duck Choi; Jong Wook Park; Joon Young Choi; Hong Seok Kim; Byong Chang Jeong; Seong Soo Jeon; Hyun Moo Lee; Han Yong Choi; Seong Il Seo

BACKGROUND Few studies assessing the functional change of each kidney following warm ischaemia after partial nephrectomy are available. OBJECTIVES Our aim was to identify the effects of the warm ischaemic time (WIT) on renal function after partial nephrectomy under the pneumoperitoneum. DESIGN, SETTING, AND PARTICIPANTS Forty-four consecutive patients who underwent laparoscopic partial nephrectomy (LPN) or robot-assisted partial nephrectomy (RAPN) from June 2008 to May 2009 for a single cT1 renal tumour were included in this prospective protocol. MEASUREMENTS Technetium Tc 99m-diethylenetriaminepentaacetic acid (Tc 99m-DTPA) renal scintigraphy was used to determine the glomerular filtration rate (GFR) of both kidneys and each kidney individually. Tc 99m-DTPA GFR was performed preoperatively and 3 mo postoperatively. In addition, we analysed Tc 99m-DTPA scintigraphy GFR regionally in the healthy areas of the affected kidney. RESULTS AND LIMITATIONS Patients with WIT > 28 min had a significantly greater decrease in the GFR of the affected kidney (p = 0.031). The GFR of the affected kidney showed a significant decrease perioperatively (46.4 ± 14.3 to 37.9 ± 11.9 ml/min per 1.73 m²; p = 0.003). The functional change of the nonaffected kidney showed an increasing trend (47.5 ± 13.8 to 51.4 ± 14.3 ml/min per 1.73 m²), although it was not statistically significant (p=0.103). Regional Tc 99m-DTPA GFR of both affected kidney and nonaffected kidney showed no significant differences perioperatively (6.3 ± 1.8 to 6.1 ± 1.9 ml/min per 1.73 m²; p = 0.641; 6.6 ± 1.9 to 7.1 ± 2.0 ml/min per 1.73 m² ; p = 0.200). On multivariate analysis, preoperative GFR, resected volume of marginal healthy tissue, and WIT were independent predictors for functional reduction of the affected kidney (p < 0.05). The study was limited by small numbers and short follow-up periods. CONCLUSIONS Stationary overall renal function after LPN or RAPN is masked possibly by functional compensation of the contralateral healthy kidney. The damage of the affected kidney estimated by scintigraphy occurs when WIT exceeds 28 min during partial nephrectomy under the pneumoperitoneum.


BJUI | 2014

Role of multiparametric 3.0‐Tesla magnetic resonance imaging in patients with prostate cancer eligible for active surveillance

Bong Hee Park; Hwang G. Jeon; Seol Ho Choo; Byong Chang Jeong; Seong Il Seo; Seong Soo Jeon; Han Y. Choi; Hyun Moo Lee

To evaluate predictors of more aggressive disease and the role of multiparametric 3.0‐T magnetic resonance imaging (MRI) in selecting patients with prostate cancer for active surveillance (AS).


The Journal of Urology | 2012

Urological laparoendoscopic single site surgery: Multi-institutional analysis of risk factors for conversion and postoperative complications

Riccardo Autorino; Jihad H. Kaouk; Rachid Yakoubi; Koon Ho Rha; Robert J. Stein; Wesley M. White; J.-U. Stolzenburg; Luca Cindolo; Evangelos Liatsikos; Soroush Rais-Bahrami; Alessandro Volpe; Deok Hyun Han; Ithaar H. Derweesh; Seung Wook Lee; Aly M. Abdel-Karim; Anibal Branco; Francesco Greco; Mohamad E. Allaf; Rene Sotelo; Panagiotis Kallidonis; Byong Chang Jeong; Sara Best; Wassim M. Bazzi; Phillip M. Pierorazio; Salah Elsalmy; Abhay Rane; Woong Kyu Han; Bo Yang; Luigi Schips; Wilson R. Molina

PURPOSE We analyzed the incidence of and risk factors for complications and conversions in a large contemporary series of patients treated with urological laparoendoscopic single site surgery. MATERIALS AND METHODS The study cohort consisted of consecutive patients treated with laparoendoscopic single site surgery between August 2007 and December 2010 at a total of 21 institutions. A logistic regression model was used to analyze the risks of conversion, and of any grade and only high grade postoperative complications. RESULTS Included in analysis were 1,163 cases. Intraoperatively complications occurred in 3.3% of cases. The overall conversion rate was 19.6% with 14.6%, 4% and 1.1% of procedures converted to reduced port laparoscopy, conventional laparoscopic/robotic surgery and open surgery, respectively. On multivariable analysis the factors significantly associated with the risk of conversion were oncological surgical indication (p=0.02), pelvic surgery (p<0.001), robotic approach (p<0.001), high difficulty score (p=0.004), extended operative time (p=0.03) and an intraoperative complication (p=0.001). A total of 120 postoperative complications occurred in 109 patients (9.4%) with major complications in only 2.4% of the entire cohort. Reconstructive procedure (p=0.03), high difficulty score (p=0.002) and extended operative time (p=0.02) predicted high grade complications. CONCLUSIONS Urological laparoendoscopic single site surgery can be done with a low complication rate, resembling that in laparoscopic series. The conversion rate suggests that early adopters of the technique have adhered to the principles of careful patient selection and safety. Besides facilitating future comparisons across institutions, this analysis can be useful to counsel patients on the current risks of urological laparoendoscopic single site surgery.


Genome Biology | 2016

Application of single-cell RNA sequencing in optimizing a combinatorial therapeutic strategy in metastatic renal cell carcinoma.

K. Kim; Hye Won Lee; Hae-Ock Lee; Hye Jin Song; Da Eun Jeong; Sang Shin; Hyunho Kim; Yoojin Shin; Do-Hyun Nam; Byong Chang Jeong; David G. Kirsch; Kyeung Min Joo; Woong-Yang Park

BackgroundIntratumoral heterogeneity hampers the success of marker-based anticancer treatment because the targeted therapy may eliminate a specific subpopulation of tumor cells while leaving others unharmed. Accordingly, a rational strategy minimizing survival of the drug-resistant subpopulation is essential to achieve long-term therapeutic efficacy.ResultsUsing single-cell RNA sequencing (RNA-seq), we examine the intratumoral heterogeneity of a pair of primary renal cell carcinoma and its lung metastasis. Activation of drug target pathways demonstrates considerable variability between the primary and metastatic sites, as well as among individual cancer cells within each site. Based on the prediction of multiple drug target pathway activation, we derive a combinatorial regimen co-targeting two mutually exclusive pathways for the metastatic cancer cells. This combinatorial strategy shows significant increase in the treatment efficacy over monotherapy in the experimental validation using patient-derived xenograft platforms in vitro and in vivo.ConclusionsOur findings demonstrate the investigational application of single-cell RNA-seq in the design of an anticancer regimen. The approach may overcome intratumoral heterogeneity which hampers the success of precision medicine.


The Journal of Urology | 2012

Does Prolonged Warm Ischemia After Partial Nephrectomy Under Pneumoperitoneum Cause Irreversible Damage to the Affected Kidney

Jae Duck Choi; Jong Wook Park; Seo Yeon Lee; Byong Chang Jeong; Seong Soo Jeon; Hyun Moo Lee; Han Yong Choi; Seong Il Seo

PURPOSE We determined the effects of warm ischemia time on the recovery of renal function after partial nephrectomy under pneumoperitoneum. MATERIALS AND METHODS In this prospective study 37 consecutive patients who underwent laparoscopic partial nephrectomy or robot-assisted partial nephrectomy between June 2008 and May 2009 to remove a single cT1 renal tumor were evaluated using (99m)Tc-diethylenetriamine pentaacetic acid renal scintigraphy preoperatively, and at 3 and 12 months postoperatively. RESULTS The most significant reduction in the glomerular filtration rate of the affected kidney at 3 and 12 months after surgery (p = 0.018, p = 0.036, respectively) was seen for a warm ischemia time cutoff of 28 minutes. The glomerular filtration rate of the affected kidney was consistently and significantly reduced at 3 and 12 months postoperatively (-22.4% to -30.6%, p <0.001) in patients with a warm ischemia time greater than 28 minutes. In contrast, no significant glomerular filtration rate change was seen in patients with a warm ischemia time of 28 minutes or less. In terms of the contributional change of the affected kidney to total renal function, there is a trend toward a recovery after an initial decrease in both groups with a warm ischemia time greater than 28 minutes vs 28 minutes or less. On multivariate analysis warm ischemia time was a strong independent predictor of glomerular filtration rate reduction even 12 months after surgery (β = -1.3; 95% CI -1.8, -0.7; p <0.001). CONCLUSIONS If the warm ischemia time is greater than 28 minutes during laparoscopic partial nephrectomy or robot-assisted partial nephrectomy, the functional damage to the affected kidney progresses even up to 1 year after surgery.


Korean Journal of Urology | 2010

Treatment Outcomes of Retrograde Intrarenal Surgery for Renal Stones and Predictive Factors of Stone-Free

Soo Hyun Lim; Byong Chang Jeong; Seong Il Seo; Seong Soo Jeon; Deok Hyun Han

Purpose The aim of this study was to evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) for the treatment of renal stones and to analyze the predictive factors for stone-free. Materials and Methods We retrospectively reviewed the records of patients who underwent RIRS for renal stones from January 2000 to July 2009. We identified 66 RIRSs (63 patients with 3 bilateral renal stones) and collected data. Stone-free and success were respectively defined as no visible stones and clinically insignificant residual stones less than 3 mm on postoperative imaging; predictive factors for stone-free were evaluated. Results Of the 66 renal stones, 18 stones (27.3%) were located in the upper pole or midpole or renal pelvis and 48 (72.7%) in the lower pole with or without others, respectively. The mean cumulative stone burden was 168.9±392.5 mm2. The immediate postoperative stone-free rate was 69.7%, and it increased to 72.7% at 1 month after surgery. The success rate was 80.3% both immediately after the operation and 1 month later. In the multivariate analysis, stone location except at the lower pole (p=0.049) and small cumulative stone burden (p=0.002) were significantly favorable predictive factors for the immediate postoperative stone-free rate. The overall complication rate was 6%. Conclusions RIRS is a safe and effective treatment for renal stones. The stone-free rate of RIRS was particularly high for renal stones with a small burden, except for those located in the lower pole. RIRS could be considered in selective patients with renal stones.

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Seong Il Seo

Sungkyunkwan University

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Wan Song

Samsung Medical Center

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H.M. Lee

Samsung Medical Center

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S.I. Seo

Samsung Medical Center

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