Franklin Lee

Comparison of lymph node yield in robot― assisted laparoscopic prostatectomy with that in open radical retropubic prostatectomy

Study Type – Therapy (case series)
Level of Evidence 4

First in Human Clinical Trial of Ultrasonic Propulsion of Kidney Stones

PURPOSE Ultrasonic propulsion is a new technology using focused ultrasound energy applied transcutaneously to reposition kidney stones. We report what are to our knowledge the findings from the first human investigational trial of ultrasonic propulsion toward the applications of expelling small stones and dislodging large obstructing stones. MATERIALS AND METHODS Subjects underwent ultrasonic propulsion while awake without sedation in clinic, or during ureteroscopy while anesthetized. Ultrasound and a pain questionnaire were completed before, during and after propulsion. The primary outcome was to reposition stones in the collecting system. Secondary outcomes included safety, controllable movement of stones and movement of stones less than 5 mm and 5 mm or greater. Adverse events were assessed weekly for 3 weeks. RESULTS Kidney stones were repositioned in 14 of 15 subjects. Of the 43 targets 28 (65%) showed some level of movement while 13 (30%) were displaced greater than 3 mm to a new location. Discomfort during the procedure was rare, mild, brief and self-limited. Stones were moved in a controlled direction with more than 30 fragments passed by 4 of the 6 subjects who had previously undergone a lithotripsy procedure. The largest stone moved was 10 mm. One patient experienced pain relief during treatment of a large stone at the ureteropelvic junction. In 4 subjects a seemingly large stone was determined to be a cluster of small passable stones after they were moved. CONCLUSIONS Ultrasonic propulsion was able to successfully reposition stones and facilitate the passage of fragments in humans. No adverse events were associated with the investigational procedure.

Use of the Acoustic Shadow Width to Determine Kidney Stone Size with Ultrasound

PURPOSE Ultrasound is known to overestimate kidney stone size. We explored measuring the acoustic shadow behind kidney stones combined with different ultrasound imaging modalities to improve stone sizing accuracy. MATERIALS AND METHODS A total of 45 calcium oxalate monohydrate stones were imaged in vitro at 3 different depths with the 3 different ultrasound imaging modalities of conventional ray line, spatial compound and harmonic imaging. The width of the stone and the width of the acoustic shadow were measured by 4 operators blinded to the true size of the stone. RESULTS Average error between the measured and true stone width was 1.4 ± 0.8 mm, 1.7 ± 0.9 mm, 0.9 ± 0.8 mm for ray line, spatial compound and harmonic imaging, respectively. Average error between the shadow width and true stone width was 0.2 ± 0.7 mm, 0.4 ± 0.7 mm and 0.0 ± 0.8 mm for ray line, spatial compound and harmonic imaging, respectively. Sizing error based on the stone width worsened with greater depth (p <0.001) while the sizing error based on the shadow width was independent of depth. CONCLUSIONS Shadow width was a more accurate measure of true stone size than a direct measurement of the stone in the ultrasound image (p <0.0001). The ultrasound imaging modality also impacted the measurement accuracy. All methods performed similarly for shadow size while harmonic imaging was the most accurate stone size modality. Overall 78% of the shadow sizes were accurate to within 1 mm, which is similar to the resolution obtained with clinical computerized tomography.

Tools to improve the accuracy of kidney stone sizing with ultrasound.

PURPOSE Ultrasound (US) overestimates stone size when compared with CT. The purpose of this work was to evaluate the overestimation of stone size with US in an in vitro water bath model and investigate methods to reduce overestimation. MATERIALS AND METHODS Ten human stones (3-12 mm) were measured using B-mode (brightness mode) US by a sonographer blinded to the true stone size. Images were captured and compared using both a commercial US machine and software-based research US device. Image gain was adjusted between moderate and high stone intensities, and the transducer-to-stone depth was varied from 6 to 10 cm. A computerized stone-sizing program was developed to outline the stone width based on a grayscale intensity threshold. RESULTS Overestimation with the commercial device increased with both gain and depth. Average overestimation at moderate and high gain was 1.9±0.8 and 2.1±0.9 mm, respectively (p=0.6). Overestimation increased an average of 22% with an every 2-cm increase in depth (p=0.02). Overestimation using the research device was 1.5±0.9 mm and did not vary with depth (p=0.28). Overestimation could be reduced to 0.02±1.1 mm (p<0.001) with the computerized stone-sizing program. However, a standardized threshold consistent across depth, system, or system settings could not be resolved. CONCLUSION Stone size is consistently overestimated with US. Overestimation increased with increasing depth and gain using the commercial machine. Overestimation was reduced and did not vary with depth, using the software-based US device. The computerized stone-sizing program shows the potential to reduce overestimation by implementing a grayscale intensity threshold for defining the stone size. More work is needed to standardize the approach, but if successful, such an approach could significantly improve stone-sizing accuracy and lead to automation of stone sizing.

Pathologic Response Rates of Gemcitabine/Cisplatin versus Methotrexate/Vinblastine/Adriamycin/Cisplatin Neoadjuvant Chemotherapy for Muscle Invasive Urothelial Bladder Cancer

Objectives. To compare pathologic outcomes after treatment with gemcitabine and cisplatin (GC) versus methotrexate, vinblastine, adriamycin, and cisplatin (MVAC) in the neoadjuvant setting. Methods. Data was retrospectively collected on 178 patients with T2-T4 bladder cancer who underwent radical cystectomy between 2003 and 2011. Outcomes of interest included those with complete response (pT0) and any response (≤pT1). Odds ratios were calculated using multivariate logistic regression. Results. Compared to those who did not receive neoadjuvant chemotherapy, there were more patients with complete response (28% versus 9%, OR 3.11 (95% CI: 1.45–6.64), P = 0.03) and any response (52% versus 25%, OR 3.23 (95% CI: 1.21–8.64), P = 0.01). Seventy-two patients received GC (n = 41) or MVAC (n = 31). CR was achieved in 29% and 22% of GC and MVAC patients, respectively (multivariate OR 0.39, 95% CI 0.10–1.58). Any response (≤pT1) was achieved in 56% of GC and 45% of MVAC patients (multivariate OR 0.45, 95% CI 0.12–1.71). Conclusions. We observed similar pathologic response rates for GC and MVAC neoadjuvant chemotherapy in this cohort of patients with muscle invasive urothelial cancer (MIBC). Our findings support the use of GC as an alternative regimen in the neoadjuvant setting.

Nonresponse to neoadjuvant chemotherapy for muscle-invasive urothelial cell carcinoma of the bladder.

BACKGROUND Cisplatin-based neoadjuvant chemotherapy (NC) is commonly used in the treatment of muscle-invasive urothelial cell carcinoma of the bladder (UC) and has been shown to improve survival. However, not all patients respond to NC, thus delaying the interval to potentially curative surgical therapy, risking disease progression and subjecting patients to potential morbidity from NC. In this study, we perform a retrospective analysis of patients who received NC prior to cystectomy to identify factors associated with nonresponse. PATIENTS AND METHODS We identified 80 patients with clinical T2 to T4, N0 to N1 UC of the bladder who received NC and underwent radical cystectomy. Nonresponse was defined as patients with higher pathologic T stage than clinical stage or patients with nodal involvement identified on final pathology. RESULTS Overall, 20% of patients were considered nonresponders. In multivariate analysis, age was predictive of nonresponse (P(trend) < .05). Compared with those < 60 years of age, those aged 60 to 69 years (odds ratio [OR], 2.9; 95% CI, 0.7-12) and those aged ≥ 70 (OR, 5.0; 95% CI, 0.9-28) had higher odds of nonresponse. Patients who received gemcitabine-carboplatin had higher odds of nonresponse compared with those who received gemcitabine-cisplatin (OR, 4.4; 95% CI, 0.8-21). CONCLUSION A subset of patients receiving NC prior to cystectomy will experience disease progression. Future study will need to better identify methods to distinguish individuals more likely to benefit from NC and those that should receive upfront cystectomy.

Role of maximal endoscopic resection before cystectomy for invasive urothelial bladder cancer

INTRODUCTION/BACKGROUND The aim of this study was to examine whether TUR of all visible endophytic tumors performed before RC, with or without NC, affects final pathologic staging. PATIENTS AND METHODS We retrospectively reviewed data from patients with clinical T2-T4N0-1 urothelial carcinoma of the bladder who underwent RC at our institution between July 2005 and November 2011. Degree of TUR was derived from review of operative reports. We used multivariate logistic regression to assess the association of maximal TUR on pT0 status at time of RC. RESULTS Of 165 eligible RC patients, 81 received NC. Reported TUR of all visible tumors was performed in 38% of patients who did not receive NC and 48% of NC patients (P = .19). Nine percent of patients who underwent maximal TUR and did not receive NC were pT0, whereas among NC patients, pT0 was seen in 39% and 19% of those with and without maximal TUR, respectively (P = .05). On multivariate analysis in all patients, maximal TUR was associated with a nonsignificant increased likelihood of pT0 status (odds ratio [OR], 2.03; 95% confidence interval [CI], 0.84-4.94), which was significant when we restricted the analysis to NC patients (OR, 3.17; 95% CI, 1.02-9.83). CONCLUSION Maximal TUR of all endophytic tumors before NC is associated with complete pathologic tumor response at RC. Candidates for NC before RC should undergo resection of all endophytic tumors when feasible. Larger series are warranted to see if maximal TUR leads to improved overall and disease-specific survival.

Differences in Upgrading of Prostate Cancer in Prostatectomies between Community and Academic Practices

Objective. To determine whether initial biopsy performed by community or academic urologists affected rates of Gleason upgrading at a tertiary referral center. Gleason upgrading from biopsy to radical prostatectomy (RP) is an important event as treatment decisions are made based on the biopsy score. Materials and Methods. We identified men undergoing RP for Gleason 3 + 3 or 3 + 4 disease at a tertiary care academic center. Biopsy performed in the community was centrally reviewed at the academic center. Multivariate logistic regression was used to determine factors associated with Gleason upgrading. Results. We reviewed 1,348 men. There was no difference in upgrading whether the biopsy was performed at academic or community sites (OR 0.9, 95% CI 0.7–1.2). Increased risk of upgrading was seen in those with >1 positive core, older men, and those with higher PSAs. Secondary pattern 4 and larger prostate size were associated with a reduction in risk of upgrading. Compared to the smallest quartile of prostate size (<35 g), those in the highest quartile (>56 g) had a 49% reduction in risk of upgrading (OR 0.51, 95% CI 0.3–0.7). Conclusion. There was no difference in upgrading between where the biopsy was performed and community and academic urologists.

Renal vasoconstriction occurs early during shockwave lithotripsy in humans

INTRODUCTION In animal models, pretreatment with low-energy shock waves and a pause decreased renal injury from shockwave lithotripsy (SWL). This is associated with an increase in perioperative renal resistive index (RI). A perioperative rise is not seen without the protective protocol, which suggests that renal vasoconstriction during SWL plays a role in protecting the kidney from injury. The purpose of our study was to investigate whether there is an increase in renal RI during SWL in humans. MATERIALS AND METHODS Subjects were prospectively recruited from two hospitals. All subjects received an initial 250 shocks at low setting, followed by a 2-minute pause. Treatment power was then increased. Measurements of the renal RI were taken before start of procedure, at 250, after 750, after 1500 shocks, and at the end of the procedure. A linear mixed-effects model was used to compare RIs at the different time points. RESULTS Fifteen patients were enrolled. Average treatment time was 46 ± 8 minutes. Average RI at pretreatment, after 250, after 750, after 1500 shocks, and post-treatment was 0.67 ± 0.06, 0.69 ± 0.08, 0.71 ± 0.07, 0.73 ± 0.07, and 0.74 ± 0.06, respectively. In adjusted analyses, RI was significantly increased after 750 shocks compared with pretreatment (p = 0.05). CONCLUSION Renal RI increases early during SWL in humans with the protective protocol. Monitoring for a rise in RI during SWL is feasible and may provide real-time feedback as to when the kidney is protected.

Improved detection of kidney stones using an optimized Doppler imaging sequence

Kidney stones have been shown to exhibit a “twinkling artifact” (TA) under Color Doppler ultrasound. Although this technique has better specificity than conventional B-mode imaging, it has lower sensitivity. To improve the overall performance of TA as a diagnostic tool, Doppler output parameters were optimized in vitro. The collected data supports a previous hypothesis that TA is caused by random oscillations of multiple micron-sized bubbles trapped in the cracks and crevices of kidney stones. A set of optimized parameters were implemented such that the acoustic output remained within the FDA approved limits. Several clinical kidney scans were performed with the optimized settings showing improved SNR relative to the default settings.