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Dive into the research topics where Doreen E. Chung is active.

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Featured researches published by Doreen E. Chung.


BJUI | 2012

Central obesity as measured by waist circumference is predictive of severity of lower urinary tract symptoms.

Richard K. Lee; Doreen E. Chung; Bilal Chughtai; Alexis E. Te; Steven A. Kaplan

Study Type – Prognosis (cohort)


The Journal of Urology | 2011

Outcomes and Complications After 532 nm Laser Prostatectomy in Anticoagulated Patients With Benign Prostatic Hyperplasia

Doreen E. Chung; James S. Wysock; Richard K. Lee; Scott R. Melamed; Steven A. Kaplan; Alexis E. Te

PURPOSE Patients on anticoagulation are at high risk for bleeding after electrocautery transurethral resection of the prostate or open prostatectomy and they are often denied surgery for symptomatic benign prostatic hyperplasia. Using photoselective vaporization of the prostate, patients at high risk may safely undergo surgery. We explored outcomes and complications after photoselective vaporization of the prostate in an anticoagulated, high risk cohort. MATERIALS AND METHODS Between 2002 and 2008, 162 men on systemic anticoagulation underwent photoselective vaporization of the prostate. Data were collected on demographics, comorbidities, complications, serum sodium, hematocrit, maximum flow rate, post-void residual urine, International Prostate Symptom Score and complications. RESULTS Mean±SD age was 72±8 years, mean baseline prostate volume was 91±49 gm and mean prostate specific antigen was 4.1±5 ng/ml. Of the patients 31 (19%) were on warfarin, 101 (62%) were on acetylsalicylic acid, 19 (12%) were on clopidogrel and 11 (7%) were on 2 or more anticoagulants. Median American Society of Anesthesiologists class was 3 and mean Charlson comorbidity index was 5. Median operative time was 105 minutes and mean energy use was 280±168 kJ. The immediate mean hematocrit decrease was 1.94%±2.42%. One patient who received excessive intravenous fluids experienced heart failure. Complications within 30 days included urinary tract infection in 4 patients (2.5%) and delayed bleeding in 6 (4%). Three of these patients (50%) required blood transfusion and 1 (17%) required reoperation. In 2 years of followup 3 patients (2%) required repeat photoselective vaporization of the prostate. No incontinence or urethral stricture developed. Significant improvements occurred in International Prostate Symptom Score, maximum flow rate and post-void residual urine. CONCLUSIONS Results support using 532 nm photoselective vaporization of the prostate in patients at high risk on systemic anticoagulation, even those on 2 or more anticoagulation agents and with a large prostate requiring longer operative time. Few complications developed and significant durable clinical improvement was seen.


Urology | 2009

Efficacy and Safety of Tolterodine Extended Release and Dutasteride in Male Overactive Bladder Patients With Prostates >30 Grams

Doreen E. Chung; Alexis E. Te; David R. Staskin; Steven A. Kaplan

OBJECTIVES To assess safety and efficacy of 4 mg tolterodine extended release (TER) with 0.5 mg dutasteride (DUT) in men with persistent overactive bladder (OAB) symptoms and lower urinary tract symptoms (LUTS) unsuccessfully treated with DUT alone. TER is indicated for OAB and DUT is indicated for LUTS from benign prostatic hyperplasia. METHODS A total of 51 men treated with DUT for >or=6 months with persistent OAB symptoms enrolled in a 12-week, open-label study, and given TER (4 mg q.h.s.). Inclusion criteria were international prostate symptom score (IPSS) >or=12, IPSS quality-of-life item >or=3, significant bother, frequency (>or=8 voids/24 h), and urgency (>or=3 episodes/24 h). Visits occurred at 4, 8, and 12 weeks. Efficacy was assessed by changes in diary endpoints and IPSS (total, storage, and voiding). Safety was assessed by changes in postvoid residual, peak flow rate (Q(max.)), adverse events, and retention. RESULTS Baseline prostate volume was 54.3 mL. TER significantly reduced frequency and urgency: 24-hour micturition frequency (-3.2, P <.02), OAB episodes (19.2%, P <.03), severe OAB episodes (71.4%, P <.05), and nighttime voiding (-0.9, P <.003). IPSS decreased with DUT (19.3-14.3) and decreased with addition of TER to 7.1 (P <.001). Storage symptoms decreased from 9.8 to 4.5 (P <.001). Dry mouth occurred in 4 (7.5%) subjects, constipation in 1 (2%), and decreased sexual function in 2 (3.9%) subjects. Postvoid residual increased by 4.2 mL, Q(max.) decreased by 0.2 mL/s, and no patients went into retention. CONCLUSIONS The combination TER and DUT was effective, safe, and well-tolerated in men with large prostates (>or=30 mL) with persistent OAB symptoms and LUTS secondary to benign prostatic hyperplasia.


International Journal of Clinical Practice | 2012

A 5-year retrospective analysis of 5α-reductase inhibitors in men with benign prostatic hyperplasia: finasteride has comparable urinary symptom efficacy and prostate volume reduction, but less sexual side effects and breast complications than dutasteride

Steven A. Kaplan; Doreen E. Chung; Richard K. Lee; S. Scofield; Alexis E. Te

Objective: We evaluated 5‐year safety, efficacy and prostate volume data from BPH patients treated with finasteride or dutasteride.


The Journal of Urology | 2010

Urethral Diverticula in Women: Discrepancies Between Magnetic Resonance Imaging and Surgical Findings

Doreen E. Chung; Rajveer S. Purohit; Jeffrey Girshman; Jerry G. Blaivas

PURPOSE Some groups consider magnetic resonance imaging the gold standard to diagnose urethral diverticula with up to 100% reported sensitivity. We describe cases contradicting this paradigm and identify reasons for discrepancies. MATERIALS AND METHODS We searched a database for women who underwent urethral diverticulum surgery from 1998 to 2008 and also underwent preoperative magnetic resonance imaging. Images were reviewed by a blinded panel of urologists and a radiologist. They came to consensus on the presence or absence, site and anatomy of urethral diverticulum or cancer, and compared operative findings. Discrepancies were classified as errors in urethral diverticulum or cancer diagnosis and errors in urethral diverticulum anatomy or site. RESULTS Of 76 patients who underwent diverticulectomy 41 also underwent magnetic resonance imaging, of whom 10 (24.4%) had a discrepancy between magnetic resonance imaging and surgical findings. In 6 of these cases there were diagnosis errors and diverticula were not seen on magnetic resonance imaging in 3. One urethral diverticulum each was misdiagnosed as Bartholins cyst and as a typical post-collagen injection appearance. A sterile abscess was incorrectly diagnosed as a urethral diverticulum. In 2 patients magnetic resonance imaging did not detect cancer within the diverticulum. A major discrepancy in anatomy made intraoperative decision making difficult in 2 patients. CONCLUSIONS In cases clinically suspicious for urethral diverticulum magnetic resonance imaging had a 24.4% error rate. Serious consequences are failure to detect cancer and suboptimal treatment for urethral diverticulum. The reason for the high magnetic resonance imaging accuracy rate in other series may be that in the absence of radiological confirmation some surgeons may choose not to perform surgery. Magnetic resonance imaging is useful to assess urethral diverticula but physicians should be aware of its limitations.


The Journal of Urology | 2010

Concordance of Near Infrared Spectroscopy With Pressure Flow Studies in Men With Lower Urinary Tract Symptoms

Doreen E. Chung; Richard K. Lee; Steven A. Kaplan; Alexis E. Te

PURPOSE Near infrared spectroscopy is a technology with the potential to diagnose bladder outlet obstruction noninvasively. We investigated the correlation between the near infrared spectroscopy algorithm classification of obstructed or unobstructed (based on near infrared spectroscopy pattern, maximum flow rate and post-void residual) and pressure flow studies in men with lower urinary tract symptoms. We also assessed whether the near infrared spectroscopy pattern itself, independent of the near infrared spectroscopy algorithm (which also includes maximum flow rate and post-void residual urine), correlates with bladder outlet obstruction. MATERIALS AND METHODS Subjects simultaneously underwent urodynamics and near infrared spectroscopy evaluation. Bladder outlet obstruction classification was based on the International Continence Society nomogram. The near infrared spectroscopy algorithm was evaluated against the comparable noninvasive algorithms with receiver operating characteristic curves. For significance the Mann-Whitney U test was used with p<0.05 considered significant. RESULTS Of 42 subjects 33 (79%) had evaluable data. Area under the curve was 0.484 for the near infrared spectroscopy algorithm relative to pressure flow diagnosis. A downward near infrared spectroscopy pattern is associated with obstruction whereas an upward pattern is associated with nonobstruction. Of 26 patients with urodynamic bladder outlet obstruction 9 (35%) had a downward, 4 (15%) a flat and 13 (50%) an upward near infrared spectroscopy pattern. Of 7 unobstructed cases 4 (57%) had a downward, 1 (14%) a flat and 2 (29%) an upward near infrared spectroscopy pattern. CONCLUSIONS The near infrared spectroscopy algorithm had a 0.484 AUC for diagnosing bladder outlet obstruction. The near infrared spectroscopy pattern component itself did not correlate strongly. The near infrared spectroscopy algorithm does not appear to provide substantial clinical usefulness in diagnosing bladder outlet obstruction in men with lower urinary tract symptoms. More studies are needed to further define and validate uses for near infrared spectroscopy in urology.


The Journal of Urology | 2012

Prostate biopsy in response to a change in nadir prostate specific antigen of 0.4 ng/ml after treatment with 5α-reductase inhibitors markedly enhances the detection rate of prostate cancer.

Steven A. Kaplan; Richard K. Lee; Doreen E. Chung; Alexis E. Te; Douglas S. Scherr; Ash Tewari; E. Darracott Vaughan

PURPOSE We examined the effect of 5α-reductase inhibitor therapy on prostate cancer detection in men with persistently increased or fluctuating prostate specific antigen and prior negative prostate cancer biopsy. MATERIALS AND METHODS A total of 276 men with prostate specific antigen greater than 4 ng/ml (208) or a prostate specific antigen velocity change of 0.75 ng/ml (68) and a normal digital rectal examination who had previously undergone biopsy a minimum of 2 times with prostate cancer not detected were given 5 mg finasteride (154) or dutasteride (122) daily. In phase 1, 97 patients had prostate specific antigen measured at 6 and 12 months with repeat transrectal ultrasonography and biopsy (12 cores) performed at 1 year. In phase 2, 179 patients underwent biopsy triggered by a change in nadir prostate specific antigen of more than 0.4 ng/ml. RESULTS In phase 1 at 1 year prostate specific antigen had decreased by 2.4 ng/ml (-46.7%), and prostate volume had decreased 7.1 ml (-17.9%). Prostate cancer was detected in 27 of 97 (27.8%) patients and the mean minimum prostate specific antigen velocity from a nadir of 0.4 ng/ml was 0.6 ng/ml. In phase 2, 48 of 179 (26.8%) men underwent repeat biopsy at a mean of 14.6 months. Of these 48 men 26 (54.1%) were found to have prostate cancer. Of the 26 men in whom prostate cancer was detected 20 (76.9%) were found to have Gleason score 7 or greater disease. CONCLUSIONS The magnitude of change in serum prostate specific antigen after 5α-reductase inhibitor therapy may be useful in diagnosing prostate cancer in patients with persistently increased or fluctuating prostate specific antigen and prior negative prostate biopsy.


Current Urology Reports | 2011

Overactive Bladder and Outlet Obstruction in Men

Doreen E. Chung; Jaspreet S. Sandhu

Lower urinary tract symptoms (LUTS), overactive bladder, (OAB), and benign prostatic hyperplasia (BPH) are very commonly experienced in men. The mainstay of pharmacotherapy for OAB is the antimuscarinic class of drugs. There has been reluctance to prescribe these agents to men with BPH due to the risk of precipitating urinary retention. Several trials have supported the efficacy and safety of antimuscarinics in treating men with LUTS, alone, or in combination with α-blocker therapy. The combination of 5-α-reductase inhibitors with antimuscarinic agents or surgery are other effective treatments for men with BPH and OAB.


The Journal of Urology | 2010

Decreasing Electrosurgical Transurethral Resection of the Prostate Surgical Volume During Graduate Medical Education Training is Associated With Increased Surgical Adverse Events

Jaspreet S. Sandhu; William I. Jaffe; Doreen E. Chung; Steven A. Kaplan; Alexis E. Te

PURPOSE In the United States the numbers of electrosurgical transurethral prostate resection procedures have been decreasing. Since electrosurgical transurethral resection of the prostate is a difficult procedure to master, we hypothesized that recent residents are lacking in training for this procedure. We used summary case log information provided by the Accreditation Council for Graduate Medical Education to determine if the number of electrosurgical transurethral prostate resection procedures performed by graduating chief residents has decreased and if there has been an increase in surgical adverse events. In addition, we investigated whether the increased number of laser procedures impacted the rate of adverse events. MATERIALS AND METHODS Summary operative data from graduating chief resident case logs were provided by the Accreditation Council for Graduate Medical Education for academic years 2001 to 2007. The numbers of electrosurgical transurethral prostate resection procedures, laser procedures and procedures for adverse events were recorded for each year. RESULTS The number of electrosurgical transurethral prostate resection procedures performed by graduating chief residents has steadily decreased from 58 in 2001 to 43 in 2007. Conversely the number of laser procedures started increasing in 2004. The rate of procedures for adverse events as a percentage of electrosurgical transurethral resection of the prostate procedures increased during the study period (from 3% in 2001 to 6% in 2007), and as a percentage of electrosurgical transurethral resection of the prostate and laser procedures the rate increased until 2005 and subsequently started decreasing. CONCLUSIONS The rate of surgical adverse events, as measured by the need for subsequent procedures, has increased during the last 7 years. However, when laser procedures are accounted for, it appears that adverse events have recently started trending down as an increasing number of laser procedures started being performed.


Current Opinion in Urology | 2010

High-power 532 nm laser prostatectomy: an update.

Doreen E. Chung; Alexis E. Te

Purpose of review Traditionally, the gold standard for treatment of benign prostatic hyperplasia was the electrocautery-based transurethral resection of the prostate. The number of laser techniques performed is rapidly increasing. Advantages of laser include decreased morbidity and shorter hospitalization. Our purpose is to review current status of the high-power 532 nm laser prostatectomy. Recent findings The 120 W, 532 nm laser differs from the 80 W, 532 nm laser in higher power, better beam collimation, and greater efficiency. Animal studies suggested that slower sweep speed might increase vaporization efficiency. However, we believe that this may not correctly guide clinical recommendations in humans due to differences in tissue composition, instrumentation, and techniques utilized. Studies demonstrated that 532 nm laser prostatectomy is safe and effective in patients with large prostates, high comorbidity, and in those taking oral anticoagulation. There is a short learning curve, reported to be less than five cases in urologists, with previous transurethral resection experience. Several studies have compared these two techniques with transurethral resection of the prostate. Frequently reported advantages of holmium laser enucleation of the prostate over the 532 nm laser prostatectomy are the availability of a pathology specimen and ability to remove a higher percentage of prostate tissue. However, the transurethral laser enucleation of the prostate addresses these concerns and has shown durable outcomes at 2-year follow-up. Summary Laser prostatectomy has proven to be a safe, efficacious, and durable surgical intervention to relieve symptomatic bladder outlet obstruction.

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Steven A. Kaplan

Icahn School of Medicine at Mount Sinai

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Jaspreet S. Sandhu

Memorial Sloan Kettering Cancer Center

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