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Featured researches published by Cathy Chen.


The Journal of Urology | 2002

LONG-TERM FOLLOWUP AFTER LAPAROSCOPIC RADICAL NEPHRECTOMY

Andrew J. Portis; Yan Yan; Jaime Landman; Cathy Chen; Peter H. Barrett; Donald D. Fentie; Yoshinari Ono; Elspeth M. McDougall; Ralph V. Clayman

PURPOSE Laparoscopic radical nephrectomy has been shown to be less morbid than traditional open radical nephrectomy. The long-term oncological effectiveness of laparoscopic radical nephrectomy remains to be established. MATERIALS AND METHODS At 3 centers patients undergoing laparoscopic radical nephrectomy before November 1, 1996 with pathologically confirmed renal cell carcinoma were identified. A representative group of patients undergoing open radical nephrectomy for clinical T1, T2 lesions was also identified. Staging, operative details and postoperative course were reviewed. Followup consisted of review of clinical, laboratory and radiological records. Kaplan-Meier analysis was performed. RESULTS The study included 64 patients treated with laparoscopic and 69 treated with open radical nephrectomy with respective average ages of 60.6 and 61.3 years at surgery. On preoperative imaging open lesions were larger (6.2 cm., range 2.5 to 15) than laparoscopic radical nephrectomy lesions (4.3 cm., range 2 to 10, p <0.001). Pathology reports revealed no difference in specimen weight (425 and 495 gm., p = 0.146) or average Fuhrman grade (1.88 and 1.78, p = 0.476) between laparoscopic and open radical nephrectomy, respectively. Median followup was 54 months (range 0 to 94) for laparoscopic and 69 months (range 8 to 114) for open radical nephrectomy. Kaplan-Meier analysis with log rank comparison revealed 5-year recurrence-free survival of 92% and 91% for laparoscopic and open radical nephrectomy, respectively (p = 0.583). At 5 years cancer specific survival was 98% and 92% (p = 0.124), and nonspecific survival was 81% and 89% (p = 0.260) for laparoscopic and open radical nephrectomy, respectively. CONCLUSIONS Laparoscopic radical nephrectomy confers long-term oncological effectiveness equivalent to traditional open radical nephrectomy.


Journal of Endourology | 2003

Laparoscopic Cyst Decortication in Autosomal Dominant Polycystic Kidney Disease: Impact on Pain, Hypertension, and Renal Function

David I. Lee; Cassio Andreoni; Jamil Rehman; Jaime Landman; Maged Ragab; Yan Yan; Cathy Chen; Alan Shindel; William Middleton; Arieh L. Shalhav; Elspeth M. McDougall; Ralph V. Clayman

BACKGROUND AND PURPOSE In patients with autosomal dominant polycystic kidney disease (ADPKD), laparoscopic cyst decortication (LCD) has been proposed as a means to relieve chronic cyst-related pain. We present our 7-year experience with LCD for ADPKD with regard to pain relief, hypertension, and renal function. PATIENTS AND METHODS Between August 1994 and February 2001, 29 ADPKD patients with chronic pain (N=29), hypertension (N=21), and renal insufficiency (N=10) underwent 35 LCD procedures. Every detectable cyst within 2 mm of the renal surface was treated. Pain relief was assessed using a pain analog scale; relative pain relief (RPR) equaled (preoperative pain score) - (postoperative pain score)/(preoperative pain score). Hypertension was evaluated using the antihypertensive therapeutic index (ATI): [(dose of blood pressure medication 1/max dose 1) + (dose med 2/max dose 2) + etc.] x 10. Renal function was assessed using the Cockcroft and Gault formula for creatinine clearance. RESULTS The mean operating room time was 4.9 hours (range 2.6-6.6 hours) with no conversions to open surgery. An average of 220 cysts (range 4-692) were treated per patient. The mean follow-up was 32.3 months (range 6-72 months). The RPR was 58%, 47%, and 63% at 12, 24, and 36 months, respectively. At 12, 24, and 36 months, 73%, 52%, and 81% of patients, respectively, noted >50% improvement in their pain compared with the preoperative situation. Five patients became normotensive, and patients improved their ATI by an average of 49% (range 11%-93%). However, six patients had worsening hypertension, with an ATI increase averaging 53% (range 11%-122%), and one patient who was not hypertensive preoperatively has since developed hypertension. The creatinine clearance changed +4%, +7%, and -2% at 12, 24, and 36 months, respectively. Only one patient had a >20% increase in creatinine clearance. The only patients with a >20% decrease in creatinine clearance were those who had a creatinine clearance <30 mg/dL preoperatively (average decrease 34% [range 20%-51%]). CONCLUSIONS For ADPKD patients with debilitating pain, extensive LCD can provide durable relief. In the majority of patients with pain and hypertension, a marked improvement in blood pressure also occurs. Cyst decortication was not associated with worsening renal function; indeed, renal function remained largely unchanged over the 3-year follow-up period.


The Journal of Urology | 2002

USE OF TITANIUM STAPLES DURING UPPER TRACT LAPAROSCOPIC RECONSTRUCTIVE SURGERY: INITIAL EXPERIENCE

Robert L. Grubb; Chandru P. Sundaram; Yan Yan; Cathy Chen; Elspeth M. McDougall; Ralph V. Clayman

PURPOSE Using nonabsorbable titanium staples in the lower urinary tract during laparoscopic nephroureterectomy has been shown to be safe. Laboratory studies of titanium staples in the upper urinary tract have likewise been favorable. Therefore, we used titanium Endo-GIA tissue staples (United States Surgical, Norwalk, Connecticut) to facilitate laparoscopic reduction pelvioplasty during laparoscopic pyeloplasty. MATERIALS AND METHODS Of the 17 cases of reduction pelvioplasty closure was done in 12 using absorbable sutures, while in 5 reduction was done with an Endo-GIA stapler. Followup consisted of office visits and telephone interviews plus radionuclide renal scans. RESULTS Average operative time was 5.5 hours in the Endo-GIA group compared with 6.8 hours in the sutured group. In the latter group extravasation in 2 patients postoperatively was managed conservatively. There was no extravasation in the stapled group. At a median subjective followup of 27 months none of the 5 patients who underwent reduction with titanium staples had symptomatic nephrolithiasis, although new onset urolithiasis developed in 1 in the sutured group. All patients had a greater than 50% decrease in pain. Renal scans at a median of 9 months showed that all ureteropelvic junction repairs were unobstructed. Additional radiographic studies in 2 patients in the stapled group showed a patent ureteropelvic junction and no stones. CONCLUSIONS Titanium staples provide rapid, secure closure of the renal pelvis during laparoscopic pyeloplasty. While the risk of stone formation is an ongoing concern, it has yet to materialize.


Journal of Endourology | 2008

Comparison of laparoscopic and percutaneous cryoablation of renal tumors: A cost analysis

Khalid H. Badwan; Keegan L. Maxwell; Ramakrishna Venkatesh; Robert S. Figenshau; Daniel B. Brown; Cathy Chen; Sam B. Bhayani

Cryoablation of renal masses is an evolving in situ ablative technique for the management of localized renal masses and can be performed in a laparoscopic or percutaneous manner. Its usefulness is increasing and correlates with the increasing frequency of incidentally diagnosed renal lesions. At present, this technique has been applied to patients deemed to be poor surgical candidates for extirpative therapy or those with a strong desire to avoid surgery, at least until long-term data become available to fully evaluate its cancer-control effectiveness. In addition, as costs become an ever more critical factor in healthcare, the costs of various management options for clinically localized kidney cancer will become as important as clinical outcomes in deciding appropriate treatment. We compare laparoscopic and percutaneous renal cryoablation from a cost perspective. Our findings indicate that percutaneous renal cryoablation may have distinct cost advantages over its laparoscopic counterpart. It remains to be seen whether these differences will translate into an overall increase in reliance on the percutaneous approach for renal cryoablation.


Journal of Endourology | 2011

Laparoscopic Retroperitoneal Lymph Node Dissection for Low-Stage Cancer: A Washington University Update

Michael W. Gardner; Timur M. Roytman; Cathy Chen; Steven B. Brandes; Adam S. Kibel; Robert L. Grubb; Sam B. Bhayani; Robert S. Figenshau

BACKGROUND AND PURPOSE At present, open retroperitoneal lymph node dissection (RPLND) remains the preferred approach at many high-volume centers for the surgical treatment of patients with low-stage testis cancer. Despite the potential advantages of a minimally invasive approach, including improved cosmesis and shorter recovery times, there remain concerns over the quality of dissection and oncologic control offered through a minimally invasive approach. Our objective was to critically evaluate the safety and intermediate-term oncologic efficacy of laparoscopic RPLND (L-RPLND). PATIENTS AND METHODS A retrospective chart review was performed, evaluating all patients who underwent L-RPLND between 2003 and 2009. Patient records were updated by telephone interview. RESULTS A total of 59 patients underwent L-RPLND during the study period, of which 13 had previously undergone chemotherapy. Mean age at treatment was 32 years. Mean operative time and estimated blood loss were 291 minutes (176-620 min) and 184 mL (range 0-1800 mL), respectively. Mean lymph node count was 21.6 (range 5-48). Mean hospital stay was 2 days (range 1-4 d). There were three open conversions because of intraoperative complications. One patient needed a transfusion. Five patients had six (8.5%) postoperative complications: three lymphoceles, two chylous ascites, and one deep venous thrombosis/pulmonary embolus. Of 18 patients with node-positive pathology, 13 received adjuvant chemotherapy and 5 underwent surveillance. Retroperitoneal recurrence did not develop in any patient undergoing surveillance during a mean follow-up of 21.3 months. One postchemotherapy RPLND (1.7%) patient experienced a retroperitoneal recurrence. CONCLUSIONS L-RPLND is a diagnostic and therapeutic treatment option for patients with low-stage testis cancer, offering excellent oncologic control and acceptable perioperative morbidity. Intermediate-term results suggest that L-RPLND is a viable alternative to the open surgical procedure. Carefully selected patients may be candidates for L-RPLND in the postchemotherapy setting.


Journal of Endourology | 2004

Laparoscopic radical prostatectomy: Washington University initial experience and prospective evaluation of quality of life

Jamil Rehman; Maged Ragab; Ramakrishna Venkatesh; Jaime Landman; David Lee; Cathy Chen; Yan Yan; Chandru P. Sundaram

BACKGROUND AND PURPOSE The laparoscopic approach to radical prostatectomy offers an alternative to the open surgical procedure with less morbidity. We prospectively collected data including a validated quality-of-life questionnaires on our first 38 laparoscopic radical prostatectomies (LRPs). The first 10 patients (group 1), second 10 patients (group II), and the most recent 18 patients (group III) were examined separately to study the learning curve for this procedure. In addition, we determined the pattern of recovery of urinary continence, potency, and quality of life. PATIENTS AND METHODS Between July 1999 and July 2002, 38 consecutive transperitoneal laparoscopic radical prostatectomies were performed for clinically localized prostate carcinoma. Patients completed quality-of-life questionnaires (Rand 36 Health Survey) before surgery as well as at 1, 3, 6, and 12 months and every 6 months thereafter. The patients were also interviewed by an individual not directly involved in patient care. RESULTS One patient (the second in our experience) was converted to the open approach because of failure to progress. The average operating time for the whole series was 423 +/- 137.6 minutes (range 215-825 minutes), the last 10 procedures taking 305 +/- 63 minutes (range 215-420 minutes). Complications consisted of one case each of intraoperative bladder injury, transient superficial peroneal nerve palsy, pulmonary embolism, and bladder neck obstruction. The bladder injury was closed laparoscopically without further complication. Bladder neck obstruction was secondary to a bladder wall fold that was treated with transurethral resection 14 months after surgery with good results. Four patients in group 1 had minor anastomotic leaks, while only one patient after that had a leak (group III). Four patients required transfusion, two intraoperatively and two postoperatively. In group III, the urethral catheter remained in place for an average of 8 days (range 6-10 days). With a mean follow-up of 22.8 months (range 9-43 months), 84.8% of the patients had perfect urinary control. Postoperatively, 9 patients (27%) were fully continent on removal of the Foley catheter. At 1, 3, 6, and 9 months postoperatively, diurnal urinary control was reported by 30.3%, 48%, 72.7%, and 84.8% of the patients, respectively. One patient needed an artificial urinary sphincter. Among the incontinent patients, 24.2% had urinary urgency, and one third of these patients reported urge incontinence. CONCLUSIONS Laparoscopic prostatectomy is a reproducible technique with a steep learning curve. Operating times and the incidence of anastomotic leaks and urinary incontinence decrease significantly after the initial 10 patients.


The Journal of Urology | 2012

Long-Term Impact of Laparoscopic Cyst Decortication on Renal Function, Hypertension and Pain Control in Patients with Autosomal Dominant Polycystic Kidney Disease

Mohammed Haseebuddin; Youssef S. Tanagho; Melissa Millar; Timur M. Roytman; Cathy Chen; Ralph V. Clayman; Brent W. Miller; Alana Desai; Brian M. Benway; Sam B. Bhayani; Robert S. Figenshau

PURPOSE Cyst proliferation in patients with autosomal dominant polycystic kidney disease is associated with renal failure, hypertension and pain. We examined the long-term impact of laparoscopic cyst decortication on renal function, hypertension and pain control in patients with adult dominant polycystic kidney disease presenting with refractory pain. MATERIALS AND METHODS Between 1994 and 2003, 37 patients with adult dominant polycystic kidney disease underwent laparoscopic cyst decortication at Barnes-Jewish Hospital. A total of 19 patients (4 male, 15 female) with at least 3-year followup were included in the study. Renal function was evaluated using the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) estimated glomerular filtration rate formula. End stage renal disease was defined as progression to transplant, dialysis or stage 5 chronic kidney disease. Hypertension was evaluated using the antihypertensive therapeutic index. Pain assessment was based primarily on a telephone questionnaire. RESULTS At a mean followup of 10.9 years (range 6.4 to 16.9), 67% of evaluable patients reported more than 50% improvement in pain. Ten patients had progression to end stage renal disease--3 dialysis, 6 transplant, and 1 chronic kidney disease stage 5. Two patients had stage 5 chronic kidney disease at initial presentation. A comparison of preoperative estimated glomerular filtration rate between patients with and those without end stage renal disease revealed a lower preoperative estimated glomerular filtration rate in the former group (43.4 vs 75.4 ml/minute/1.73 m(2), p = 0.01). Of the patients 53% had an improved or stable antihypertensive therapeutic index at last followup, although no improvement in mean overall antihypertensive therapeutic index was noted (4.7 pre-laparoscopic cyst decortications vs 7.0 post-laparoscopic cyst decortications, p = 0.28). CONCLUSIONS Durable pain relief but not hypertension control was seen at 10-year followup. Preoperative estimated glomerular filtration rate is a strong predictor of post-laparoscopic cyst decortication progression to end stage renal disease. A cautious approach with laparoscopic cyst decortication should be taken in patients with poor preoperative renal function.


The Journal of Urology | 2011

The Efficacy of Oral Midazolam for Decreasing Anxiety in Children Undergoing Voiding Cystourethrogram: A Randomized, Double-Blind, Placebo Controlled Study

Genoa G. Ferguson; Cathy Chen; Yan Yan; Michele E. Royer; Mary Campigotto; Erica J. Traxel; Douglas E. Coplen

PURPOSE Voiding cystourethrogram is an invasive test that evokes anxiety. Our primary aim was to determine whether midazolam is beneficial in decreasing anxiety in children who undergo voiding cystourethrogram. Secondary aims were an examination of parent anxiety, health care professional perceptions and post-procedure behavioral outcomes in children after voiding cystourethrogram. MATERIALS AND METHODS A total of 44 children were randomized to placebo or oral midazolam before voiding cystourethrogram in double-blind fashion. The Modified Yale Preoperative Anxiety Scale was used to evaluate child behavior before and during voiding cystourethrogram, and the Post Hospitalization Behavior Questionnaire was used to investigate any short-term and intermediate-term behavioral outcomes. The State-Trait Anxiety Inventory was used to evaluate parent personal anxiety during voiding cystourethrogram. A separate questionnaire was administered to radiology staff. Statistical analysis included the 2-sample t and Fisher exact tests. RESULTS There was no difference in Modified Yale Preoperative Anxiety Scale scores in children randomized to midazolam or placebo. There was also no significant difference in parent anxiety. Radiology care providers identified no reliable benefit when blinded to sedation vs placebo. We did not note any post-procedural behavior issues after voiding cystourethrogram at up to 6 months of followup. CONCLUSIONS Midazolam may not significantly help with child or parent anxiety during voiding cystourethrogram. No reliable benefit was noted according to radiology health care provider perception and there was no significant post-procedural behavior benefit. Midazolam may not provide a significant benefit in decreasing anxiety during voiding cystourethrogram.


The Journal of Urology | 2003

Laparoscopic Pyeloplasty for Secondary Ureteropelvic Junction Obstruction

Chandru P. Sundaram; Robert L. Grubb; Jamil Rehman; Yan Yan; Cathy Chen; Jaime Landman; Elspeth M. McDougall; Ralph V. Clayman


The Journal of Urology | 2004

PROSPECTIVE COMPARISON OF THE IMMUNOLOGICAL AND STRESS RESPONSE FOLLOWING LAPAROSCOPIC AND OPEN SURGERY FOR LOCALIZED RENAL CELL CARCINOMA

Jaime Landman; Ephrem O. Olweny; Chandru P. Sundaram; Cathy Chen; Jamil Rehman; David Lee; Arieh L. Shalhav; Andrew J. Portis; Elspeth M. McDougall; Ralph V. Clayman

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Jaime Landman

University of California

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Yan Yan

Washington University in St. Louis

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Elspeth M. McDougall

Washington University in St. Louis

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Ramakrishna Venkatesh

Washington University in St. Louis

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Robert S. Figenshau

Washington University in St. Louis

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Sam B. Bhayani

Washington University in St. Louis

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Jamil Rehman

Washington University in St. Louis

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Robert L. Grubb

Washington University in St. Louis

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