Chong Koo Sul

Efficacy and Safety of Sunitinib on Metastatic Renal Cell Carcinoma: A Single-Institution Experience

Purpose We assessed the efficacy and safety of the tyrosine kinase inhibitor sunitinib in Korean patients with metastatic renal cell carcinoma (mRCC). Materials and Methods Between September 2007 and December 2009, all twenty-one patients who had mRCC with a clear-cell component were retrospectively reviewed. Sunitinib was administered orally at a dose of 50 mg daily until disease progression or intolerance to treatment occurred. The primary end point of this study was the objective tumor response assessed by Response Evaluation Criteria in Solid Tumors (RECIST), and the secondary end points were progression-free survival (PFS) and overall survival (OS) rates as well as assessment of adverse effects. Results After a median of 17.4 months (range, 5.7-33.1 months) of treatment, 11 patients (52.4%) had an objective response with a complete response in 1 patient (4.8%), and a partial response in 10 patients (47.6%) as the best tumor response. The median PFS was 13.4 months (95% confidence interval [CI], range, 12.3-14.5 months), and the median OS was 28.1 months (95% CI, 21.8-34.4 months). All patients experienced adverse events of some sort, but the studied treatment protocol was well tolerated and most patients experienced reversible grade 1 or 2 toxicities. Conclusions Sunitinib was efficacious in the treatment of metastatic clear-cell RCC, and was well tolerated in Korean patients. Although sunitinib treatment-related adverse events such as hand-foot syndrome and facial/generalized edema were observed with a higher incidence than in Western trials, they were mainly mild to moderate, and readily managed.

Comparison of Laparoscopic Radiofrequency Ablation and Open Partial Nephrectomy in Patients With a Small Renal Mass

Purpose We have performed both open partial nephrectomy (OPN) and laparoscopic radiofrequency ablation (RFA) on selected patients since January 2007 and have been following these patients through serial laboratory assessments and computed tomography (CT). The purpose of the present study was to evaluate long-term oncologic outcomes and renal function status for laparoscopic RFA versus OPN at a minimum follow-up of 3 years. Materials and Methods A total of 55 patients with exophytic, single small renal masses were treated with either OPN (n=14) or laparoscopic RFA (n=41) by a single surgeon. The indications for laparoscopic RFA were as follows: 1) cases with the greatest dimension of the renal mass <3 cm, and 2) cases in which the collecting system, renal calyx, and great vessels were free from the tumor margins by 1 cm. Results The estimated blood loss (EBL), the operation time, and the mean number of hospital days was significantly lower in the laparoscopic RFA group than in the OPN group. Oncologic data did not differ significantly between the two groups. Creatine clearance levels did not differ significantly compared with those before the operation in either group. Conclusions Our data suggest excellent therapeutic outcomes with laparoscopic RFA with achievement of effective operative times, hospital stays, and EBL compared with OPN. According to our indications for laparoscopic RFA, laparoscopic RFA is an effective minimally invasive therapy for the treatment of small renal masses, yielding oncologic outcomes and renal function equivalent to those of OPN.

Increased Expression of Neuregulin 1 and erbB2 Tyrosine Kinase in the Bladder of Rats With Cyclophosphamide-Induced Interstitial Cystitis

Purpose: The aim of this study was to evaluate changes in expressions of neuregulin (NRG)1 and erbB2 tyrosine kinase (ErbB2) in bladders of rats with cyclophosphamide (CYP)-induced interstitial cystitis (IC). Methods: Twenty-four Sprague-Dawley rats were divided into the IC group (n=16) and the control group (n=8). After inducing IC with intraperitoneal CYP injection, expressions of NRG1 and ErbB2 were analyzed using western blotting and reverse transcriptase-polymerase chain reaction. Results: In Western blotting, relative intensities and distributions of both NRG1 and ErbB2 were approximately 1.5- and 3.2-fold higher, respectively, in the IC group than in the control group (mean±standard deviation: 1.42±0.09 vs. 0.93±0.15 and 0.93±0.16 vs. 0.29±0.08, P<0.05). In the rat bladder samples, mRNA expression levels of NRG1 and ErbB2 were higher in the IC group than in the control group (P<0.05). Conclusions: Our study has demonstrated significant changes in mRNA expression and immunoreactivity of NRG1 and ErbB2 receptors in the urinary bladder after CYP-induced IC. These results suggest that the up-regulated NRG1 may play a role in inducing an overactive bladder and promoting regeneration in the inflammatory bladder with CYP-induced IC.

Expression of Aquaporin-3 in Ipsilateral Rat Kidney With Unilateral Partial Ureteral Obstruction

Purpose Aquaporin (AQP), a protein located in the cellular membrane, allows rapid passage of water across the cell membrane. Various AQP subtypes have been associated with ureteral obstruction. In particular, AQP3 has two functions: water and glycerol transport. The aim of this study was to investigate the expression of AQP3 in the ipsilateral rat kidney in unilateral partial ureteral obstruction (UPUO). Materials and Methods Sprague-Dawley rats (n=30, 200-250 g) were divided into two groups. A sham operation was performed in the control group (n=10) and UPUO of the left upper ureter with a silicone tube was induced in the UPUO group (n=20). The left kidney was obtained from both groups 7 days after the operations. The kidney specimens underwent immunofluorescent staining with AQP3 monoclonal antibody, and the density of AQP3 in the tissue was measured with an image analyzer. Results In the UPUO group, thinning of the epithelial layer and infiltration of inflammatory cells was seen along with the localized expression of AQP3 in the basolateral aspect of the principal collecting duct cells. The mean optical density of AQP3 was significantly lower in the UPUO group than in the control group (100.9±17.5 compared with 131.7±16.9; p<0.001). Conclusions These results suggest that a decrease in the expression of AQP3 may be the result of a urinary stasis reaction caused by UPUO in response to local and intrarenal factors. These changes suggest that AQP3 may have a pathophysiological role in UPUO.

Neoadjuvant Hormonal Therapy Preceding Radical Prostatectomy for Clinically Localized Prostate Cancer: Early Postoperative Complications and Biochemical Recurrence

Purpose The effect of neoadjuvant hormonal therapy (NHT) on radical retropubic prostatectomy (RRP) for prostate cancer is various and remains a controversy for urologists. We conducted this study to comparatively evaluate whether NHT before RRP is indicated and beneficial in the aspects of postoperative complications, positive surgical margin, and biochemical recurrence. Materials and Methods Between September 2006 and December 2009, 69 men were scheduled for RRP as a treatment for clinically localized and locally advanced prostate cancer and were divided into two groups. Group 1 (n=31, 44.9%) was treated with RRP only, and group 2 (n=38, 55.1%) underwent RRP with preoperative NHT. We evaluated clinical parameters, surgical parameters, and the positive margin rate in surgical specimens and the biochemical recurrence rate. Results There were no statistical differences in age, body mass index (BMI), preoperative biopsy Gleason score, initial serum prostate-specific antigen (PSA) levels, International Prostate Symptom Score (IPSS), or quality of life (QoL) between the two groups (p>0.05). We also observed no differences in the transfusion rate, mean catheterization time, or positive margin rate (p>0.05). However, the mean operative time was significantly higher in the RRP with preoperative NHT group than in the other group (p=0.034). There was no significant difference in the biochemical recurrence rate during the last follow-up according to NHT (p=0.102) or positive surgical margin (p=0.473). Conclusions These results suggest that there were no clinical benefits to the administration of NHT before RRP from the viewpoint of biochemical recurrence.

Is the Expression of Androgen Receptor Protein Associated With the Length of AC Repeats in the Type III 5-α Reductase Gene in Prostate Cancer Patients?

Purpose Type III 5-α reductase (SRD5A3; steroid 5-α reductase 3) may be associated with the progression of prostate cancer (PCa). The aim of our study was to determine whether the length of AC repeats in the SRD5A3 gene is associated with the risk of PCa and the expression of androgen receptor (AR) protein in Korean men. Materials and Methods We compared the length of AC repeats in the short tandem repeat (STR) region of the SRD5A3 gene in 68 PCa patients and 81 control subjects by genotyping. A total of 55 patients in the PCa group underwent radical prostatectomy. We evaluated the expression of AR protein by using Western blotting and tested the association between the type of AC repeats in the SRD5A3 gene and AR protein expression and clinical and pathologic parameters. Results The short type of STR had less than 21 copies of AC repeats in the SRD5A3 gene. The SS type (short and short type) of STR of the SRD5A3 gene was 2.2 times as likely to occur in PCa patients as in controls (odds ratio, 2.21; 95% confidence interval, 1.14 to 4.31; p=0.019). However, AC repeats of the SRD5A3 gene were not associated with AR protein expression or clinical or pathologic parameters in PCa samples. Conclusions These results suggest that the short AC repeats of SRD5A3 polymorphism are associated with an increased risk of PCa. SRD5A3 polymorphism may contribute to a genetic predisposition for PCa.

Prospective Study Comparing the Suprapubic Arc (Sparc) Procedure and the Transobturator (Monarc) Procedure for Treating Female Stress Urinary Incontinence

Objectives: In a comparative trial we evaluated the efficacy and safety of the suprapubic arch (Sparc) and transobturator (Monarc) procedures for the treatment of female stress urinary incontinence (SUI).

Successful Endourologic Management of Lower Pole Moiety Ureteropelvic Junction Obstruction in a Partially Duplicated Collecting System

We present two cases of symptomatic lower pole moiety ureteropelvic junction obstruction (UPJO) in a partially duplicated collecting system that were successfully treated with minimally invasive endourologic procedures. In the first case, we performed retrograde endopyelotomy with the Acucise® ureteral cutting balloon device, and in the latter case, we performed percutaneous nephrolithotomy and antegrade endopyelotomy because of the presence of multiple renal stones. Subsequent intravenous pyelography confirmed marked resolution of the obstruction, and both patients remained asymptomatic during 1 year of follow-up.