Jonathan Mobley

Urine Aquaporin 1 and Perilipin 2 Differentiate Renal Carcinomas From Other Imaged Renal Masses and Bladder and Prostate Cancer

OBJECTIVE To evaluate the sensitivity and specificity of urine aquaporin 1 (AQP1) and perilipin 2 (PLIN2) concentrations to diagnose clear cell or papillary renal cell carcinoma (RCC) by comparing urine concentrations of these unique biomarkers in patients with RCC, noncancer renal masses, bladder cancer, and prostate cancer. METHODS From February 1, 2012, through October 31, 2012, preoperative urine samples were obtained from patients with a presumptive diagnosis of RCC based on an imaged renal mass, prostate cancer, or transitional cell bladder cancer. Imaged renal masses were diagnosed postnephrectomy—as malignant or benign—by histology. Urine AQP1 and PLIN2 concentrations were measured by using a sensitive and specific Western blot and normalized to urine creatinine concentration. RESULTS Median concentrations of urine AQP1 and PLIN2 in patients with clear cell and papillary RCC (n=47) were 29 and 36 relative absorbance units/mg urine creatinine, respectively. In contrast, median concentrations in patients with bladder cancer (n=22) and prostate cancer (n=27), patients with chromophobe tumors (n=7), and patients with benign renal oncocytomas (n=9) and angiomyolipomas (n=7) were all less than 10 relative absorbance units/mg urine creatinine (Kruskal-Wallis test, P<.001 vs RCC for both biomarkers) and comparable with those in healthy controls. The area under the receiver operating characteristic curve ranged from 0.99 to 1.00 for both biomarkers. CONCLUSION These results support the specificity and sensitivity of urine AQP1 and PLIN2 concentrations for RCC. These novel tumor-specific proteins have high clinical validity and high potential as specific screening biomarkers for clear cell and papillary RCC as well as in the differential diagnosis of imaged renal masses. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00851994.

The second “time-out”: a surgical safety checklist for lengthy robotic surgeries

Robotic surgeries of long duration are associated with both increased risks to patients as well as distinct challenges for care providers. We propose a surgical checklist, to be completed during a second “time-out”, aimed at reducing peri-operative complications and addressing obstacles presented by lengthy robotic surgeries. A review of the literature was performed to identify the most common complications of robotic surgeries with extended operative times. A surgical checklist was developed with the goal of addressing these issues and maximizing patient safety. Extended operative times during robotic surgery increase patient risk for position-related complications and other adverse events. These cases also raise concerns for surgical, anesthesia, and nursing staff which are less common in shorter, non-robotic operations. Key elements of the checklist were designed to coordinate operative staff in verifying patient safety while addressing the unique concerns within each specialty. As robotic surgery is increasingly utilized, operations with long surgical times may become more common due to increased case complexity and surgeons overcoming the learning curve. A standardized surgical checklist, conducted three to four hours after the start of surgery, may enhance perioperative patient safety and quality of care.

Patients with Pathologically Proven Renal Disease Have Similar Declines in Renal Function Following Robot-Assisted Partial Nephrectomy.

OBJECTIVE To determine if patients with pathological, medical renal disease, defined as evidence of pathological abnormalities indicative of renal damage in the non-neoplastic partial nephrectomy specimens, have worsened functional outcomes following robot-assisted partial nephrectomy (RPN). MATERIALS AND METHODS Sixty patients with and 101 without pathologically proven renal disease on non-neoplastic renal specimens were evaluated for differences in postoperative outcomes following RPN. Multiple linear regression modeling assessed for factors influencing early and late declines in renal function. RESULTS The two groups were similar in all preoperative parameters. Both patients with and without pathological renal disease had similar lengths of hospitalization, transfusions, and complication rates. The percent change in the glomerular filtration rate was similar for patients with and without pathological renal disease (-8.8% vs -12.2%, p=0.194). Patients with pathological renal disease had less chronic kidney disease (CKD) upstaging than patients without renal disease (18.3% vs 39.6%, p=0.006). Increasing age (p=0.030) and higher preoperative glomerular filtration rates (p=0.044) predicted worse late percentage declines in renal function, while increased warm ischemia time predicted late CKD upstaging (p=0.043). CONCLUSION The presence of pathological renal disease in non-neoplastic renal tissue did not place patients at risk for worsened postoperative complications or renal function deterioration following RPN.

In Vivo Evaluation of a Reverse Thermosensitive Polymer for Ureteroscopy with Laser Lithotripsy: Porcine Model

PURPOSE To evaluate the effects of a reverse thermosensitive polymer during ureteroscopy with laser lithotripsy in an in vivo porcine model. MATERIALS AND METHODS Six pigs underwent general anesthesia followed by bilateral ureteroscopy with laser lithotripsy of stone phantoms while measuring intrapelvic renal pressures through bilateral nephrostomy tubes. The procedures were performed in one ureter with the reverse thermosensitive polymer and in the contralateral, control ureter without the reverse thermosensitive polymer. Stone migration lengths, operative times, laser times, laser energy usage, intrapelvic pressures, and postnecropsy histologic examinations of the ureters were compared between the two groups. RESULTS Bilateral ureteroscopy with lithotripsy was successfully performed in five of six pigs. In one pig, only the unilateral control was performed, because the ureter was too narrow to complete the contralateral side. The mean laser time was 12.8 minutes shorter with the use of the reverse thermosensitive polymer group than in the controls (P=0.021). The procedure time, laser energy usage, and retropulsion length was shorter in the reverse thermosensitive polymer group, but did not reach significance. Between the two groups, there was no difference in mean renal pelvic pressures, peak renal pelvic pressures, or postprocedure histologic examinations of the ureters. CONCLUSIONS The use of a reverse thermosensitive polymer during ureteroscopy with lithotripsy may have greater advantages beyond preventing stone retropulsion. Here, the use of a reverse thermosensitive polymer during ureteroscopy with lithotripsy resulted in a significant decrease in laser times. Further clinical investigations could further delineate the advantages of using a reverse thermosensitive polymer during intracorporeal lithotripsy.

Robot-Assisted Partial Nephrectomy: Complex Tumors and Evolving Techniques

Several investigators have demonstrated the feasibility of robot-assisted partial nephrectomy (RAPN) for the management of renal tumors of increasing size and greater anatomical complexity, allowing RAPN to be offered to more patients, including those with larger, endophytic, and central masses. In this chapter, we examine the utility of RAPN for complex and challenging renal masses, highlighting recent innovations in technique and approach as well as emerging techniques that provide a window into the future of RAPN. Studies have demonstrated that RAPN can be performed safely and with acceptable outcomes for increasingly complex renal tumors. As nascent procedure, RAPN continues to evolve in its technique. New frontiers in RAPN aimed at enhancing the surgeon’s ability to provide excellent oncologic control and hemostatic repair of the renal defect continue to be explored. Future technical innovation in robotic instrumentation may also enhance the RAPN technique.

Gas-Producing Renal Infection Presenting as Pneumaturia: A Case Report

We present a case of persistent pneumaturia of one-year duration in a fifty-five-year-old male with a history of spinal cord injury. The evaluation demonstrated gas throughout the collecting system attributable to a urinary tract infection with a gas-forming organism, Klebsiella pneumoniae.