Current controversies on the role of lymphadenectomy for prostate cancer.

Lymph node dissection is part of the standard treatment protocol for various cancers, but its role in prostate cancer has been debatable for some time. Pelvic lymphadenectomy has been shown to better help stage prostate cancer patients, but has yet to be definitively proven to be of any benefit for survival. Various templates for lymph node dissections exist, and though some national guidelines have endorsed an extended pelvic node dissection, the choice of template is still controversial. Pelvic lymphadenectomy may lead to a slightly higher rate complications and operative time, and their use must be judiciously applied to patients with a high enough risk of lymph node involvement. We present a comprehensive review of the literature regarding the benefits and harms of lymph node dissection in prostate cancer.

Robotic Partial Nephrectomy in Patients with Chronic Kidney Disease: Objective Measurement of Short- and Long-Term Renal Functional Outcomes.

BACKGROUND: Minimal literature informs the use of robotic partial nephrectomy (RPN) in patients with chronic kidney disease (CKD). Therefore, we evaluated the renal functional outcomes in CKD patients undergoing RPN. METHODS: We reviewed a prospective database of patients undergoing RPN 2010 to 2015 and identified 182 patients who had preoperative and postoperative nuclear renal scintigraphy (at 2 and 12 months postop). Preoperative and 12-month postoperative eGFR (mL/min/1.73 m2, by MDRD) were calculated. CKD was defined as eGFR ≤60 mL/min/1.73 m2 (CKD stages III and IV). Changes in creatinine, eGFR, and split function on mercaptoacetyltriglycine (MAG)-3 scan were compared by baseline CKD status. Correlations between pre- and postoperative eGFR were calculated. RESULTS: Of 182 patients, 30 (16.5%) had baseline CKD. Preoperative eGFR was 48.5 and 99.0 in CKD and non-CKD patients, respectively (p < 0.001). From preoperation to 12 months postoperation, eGFR decreased by 2.8 and 1.1 mL/min/1.73 m2, respectively (p = 0.6). On MAG-3 scan, the contribution of the surgical kidney to overall renal function decreased by 5.0% and 4.8% (p = 0.9) in the CKD and non-CKD cohorts, respectively. When comparing renal scans at 2 and 12 months postoperation, in both groups the surgical kidney significantly recovered (both p < 0.001) and the patterns of kidney function recovery was similar in both groups (CKD +2.0%, non-CKD +1.4%, p = 0.6). On long-term follow-up (>2 years), eGFR did not change significantly in either the CKD or non-CKD group (-2.8 vs -1.1 mL/min/1.73 m2, p = 0.6). On pathology, tumors were more frequently malignant in CKD vs non-CKD patients (93.3% vs 73.2%, p = 0.02) and of higher Fuhrman Grade (grade ≥3: 49.7% vs 28.1%, p < 0.001). CONCLUSION: RPN is a reasonable treatment option in patients with CKD, as it did not lead to a greater decline in renal function contributed by the surgical kidney. The patterns of kidney function recovery after surgery are similar between patients with and without CKD.

New methods for estimating follow-up rates in cohort studies.

BACKGROUND: The follow-up rate, a standard index of the completeness of follow-up, is important for assessing the validity of a cohort study. A common method for estimating the follow-up rate, the "Percentage Method", defined as the fraction of all enrollees who developed the event of interest or had complete follow-up, can severely underestimate the degree of follow-up. Alternatively, the median follow-up time does not indicate the completeness of follow-up, and the reverse Kaplan-Meier based method and Clark's Completeness Index (CCI) also have limitations. METHODS: We propose a new definition for the follow-up rate, the Person-Time Follow-up Rate (PTFR), which is the observed person-time divided by total person-time assuming no dropouts. The PTFR cannot be calculated directly since the event times for dropouts are not observed. Therefore, two estimation methods are proposed: a formal person-time method (FPT) in which the expected total follow-up time is calculated using the event rate estimated from the observed data, and a simplified person-time method (SPT) that avoids estimation of the event rate by assigning full follow-up time to all events. Simulations were conducted to measure the accuracy of each method, and each method was applied to a prostate cancer recurrence study dataset. RESULTS: Simulation results showed that the FPT has the highest accuracy overall. In most situations, the computationally simpler SPT and CCI methods are only slightly biased. When applied to a retrospective cohort study of cancer recurrence, the FPT, CCI and SPT showed substantially greater 5-year follow-up than the Percentage Method (92%, 92% and 93% vs 68%). CONCLUSIONS: The Person-time methods correct a systematic error in the standard Percentage Method for calculating follow-up rates. The easy to use SPT and CCI methods can be used in tandem to obtain an accurate and tight interval for PTFR. However, the FPT is recommended when event rates and dropout rates are high.

Value of Nephrometry Score Constituents on Perioperative Outcomes and Split Renal Function in Patients Undergoing Minimally Invasive Partial Nephrectomy.

OBJECTIVE: To assess the relationship between individual nephrometry score (NS) constituents (RENAL) on perioperative outcomes and renal function of the surgical kidney in patients undergoing laparoscopic partial nephrectomy or robotic-assisted partial nephrectomy. MATERIALS AND METHODS: Two hundred forty-five patients who underwent laparoscopic partial nephrectomy or robotic-assisted partial nephrectomy between 2005 and 2014 were retrospectively reviewed. Each renal mass' NS was calculated from preoperative computed tomography imaging. Multivariate regression analysis was used to evaluate the effect of NS variables on perioperative outcomes and change in overall renal function (as estimated by glomerular filtration rate) from preoperative to 1-year postoperative. A cohort analysis assessed the effect of NS variables on change in split renal function of the surgical kidney from pre- to postoperative based on nuclear medicine renal scintigraphy. RESULTS: Tumor radius (R), endophytic nature (E), and nearness to collecting system (N) variables significantly and incrementally predicted a longer operative time and warm ischemia time. Overall renal function based on glomerular filtration rate was not affected by any NS variable. However, percent function of the surgical kidney by renal scintigraphy significantly decreased postoperatively as R and E values increased. CONCLUSION: R, E, and N were associated with significant changes in warm ischemia time and operative time. R and E were associated with a significant decrease in split renal function of the surgical kidney at 1 year after surgery but not with overall renal function. R, E, and N are the NS constituents most relevant to perioperative outcomes and postoperative differential renal function after partial nephrectomy.

Robot-assisted extravesical vesicovaginal fistula repair utilizing laparoscopically mobilized omental flap interposition.

INTRODUCTION AND HYPOTHESIS: High vesicovaginal fistulas (VVF) in the setting of good apical support are best repaired via a transabdominal approach. Laparoscopic VVF repair was first reported in 1998. Several series of robot-assisted VVF repairs have since been published. The robot-assisted approach allows repair of high apical vaginal fistulas while avoiding the morbidity of laparotomy, shortening convalescence, and facilitating the use of omental interposition flaps. This video presents the technique for robot-assisted extravesical VVF repair utilizing a laparoscopically mobilized omental flap. METHODS: A 43-year-old woman developed a VVF after a total abdominal hysterectomy for fibroids. Pre-operative CT urogram and office cystoscopy confirmed the diagnosis and ruled out ureteral involvement. She underwent a robot-assisted extravesical VVF repair utilizing a laparoscopically mobilized omental flap. RESULTS: The surgery was uncomplicated, and the patient was discharged on post-operative day 1. A cystogram 2 weeks post-operatively revealed no evidence of a fistula. At 3 months follow-up, the patient denied any urinary incontinence. CONCLUSIONS: Robot-assisted extravesical VVF repair avoids the morbidity of a laparotomy, provides excellent exposure, and avoids a large cystotomy. It maintains vaginal length and allows for significantly better visualization compared with the transvaginal approach. This repair offers improved outcomes for certain patients depending on their history, anatomy, and the surgeon's experience.

Safer Surgery by Learning from Complications: A Focus on Robotic Prostate Surgery.

BACKGROUND: The uptake of robotic surgery has led to changes in potential operative complications, as many surgeons learn minimally invasive surgery, and has allowed the documentation of such complications through the routine collection of intraoperative video. OBJECTIVE: We documented intraoperative complications from robot-assisted radical prostatectomy (RARP) with the aim of reporting the mechanisms, etiology, and necessary steps to avoid them. Our goal was to facilitate learning from these complications to improve patient care. DESIGN, SETTING, AND PARTICIPANTS: Contributors delivered videos of complications that occurred during laparoscopic and robotic prostatectomy between 2010 and 2015. SURGICAL PROCEDURE: Surgical footage was available for a variety of complications during RARP. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Based on these videos, a literature search was performed using relevant terms (prostatectomy, robotic, complications), and the intraoperative steps of the procedures and methods of preventing complications were outlined. RESULTS AND LIMITATIONS: As a major surgical procedure, RARP has much potential for intra- and postoperative complications related to patient positioning, access, and the procedure itself. However, with a dedicated approach, increasing experience, a low index of suspicion, and strict adherence to safety measures, we suggest that the majority of such complications are preventable. CONCLUSIONS: Considering the complexity of the procedure, RARP is safe and reproducible for the surgical management of prostate cancer. Insight from experienced surgeons may allow surgeons to avoid complications during the learning curve. PATIENT SUMMARY: Robot-assisted radical prostatectomy has potential for intra- and postoperative complications, but with a dedicated approach, increasing experience, a low index of suspicion, and strict adherence to safety measures, most complications are preventable.

Respiratory gas exchange during robotic-assisted laparoscopic radical prostatectomy.

STUDY OBJECTIVE: Robotic-assisted laparoscopic prostatectomy requires patients to be secured in a steep Trendelenburg position for several hours. Added to the CO2 pneumoperitoneum that is created, this positioning invariably restricts diaphragmatic and chest wall excursion, which can adversely affect respiratory gas exchange. This study sought to measure the extent of respiratory gas change during this procedure. DESIGN: Retrospective, institutional review board approved. SETTING: Operating room. PATIENTS: N = 186 males, American Society of Anesthesiologists 2-3, with prostatic carcinoma undergoing robotic-assisted laparoscopic radical prostatectomy. INTERVENTIONS: Arterial blood gases and noninvasive respiratory measurements were recorded for those patients (n = 32) in whom a radial arterial catheter had been inserted intraoperatively, specifically timed to different phases of the procedure: supine lithotomy, steep Trendelenburg, and return to supine. Ventilatory parameters were standardized. MEASUREMENTS: Systemic blood pressure, heart rate, respiratory rate, Pao2, Paco2, oxygen saturation as measured by pulse oximetry, and end-tidal carbon dioxide pressure. MAIN RESULTS: Although no patients developed perioperative respiratory complications, the Pao2 invariably fell (395 vs 316 mm Hg; P = .001) while the patients were in steep Trendelenburg, and the Paco2-end-tidal carbon dioxide pressure rose (10.0 vs 13.4 mm Hg; P < .0001). Upon return to supine, patients' respiratory measurements promptly returned to within 15% of baseline. Subgroup analysis for high-BMI vs low-BMI patients as well as for patients with pulmonary disease and/or a smoking history showed similar individual effects and only small, although significant, respiratory gas exchange aberrations. CONCLUSIONS: Positioning patients with a CO2 pneumoperitoneum in steep Trendelenburg for several hours imposes restriction of diaphragmatic and chest wall movement sufficient for respiratory gas exchange to be adversely affected. Return of function to within 15% of baseline occurred within minutes after return to supine and release of the CO2 pneumoperitoneum. No patients during the study period developed pulmonary complications that required alteration in their level of care.

The impact of obesity on prostate cancer recurrence observed after exclusion of diabetics.

PURPOSE: Although overall there is a positive association between obesity and risk of prostate cancer (PrCa) recurrence, results of individual studies are somewhat inconsistent. We investigated whether the failure to exclude diabetics in prior studies could have increased the likelihood of conflicting results. METHODS: A total of 610 PrCa patients who underwent radical prostatectomy between 2005 and 2012 were followed for recurrence, defined as a rise in serum PSA ≥ 0.2 ng/ml following surgery. Body mass index (BMI) and history of type 2 diabetes were documented prior to PrCa surgery. The analysis was conducted using Cox proportional hazard models. RESULTS: Obesity (25.6 %) and diabetes (18.7 %) were common in this cohort. There were 87 (14.3 %) recurrence events during a median follow-up of 30.8 months after surgery among the 610 patients. When analyzed among all PrCa patients, no association was observed between BMI/obesity and PrCa recurrence. However, when analysis was limited to non-diabetics, obese men had a 2.27-fold increased risk (95 % CI 1.17-4.41) of PrCa recurrence relative to normal weight men, after adjusting for age and clinical/pathological tumor characteristics. CONCLUSIONS: This study found a greater than twofold association between obesity/BMI and PrCa recurrence in non-diabetics. We anticipated these results because the relationship between BMI/obesity and the biologic factors that may underlie the PrCa recurrence-BMI/obesity association, such as insulin, may be altered by the use of anti-diabetes medication or diminished beta-cell insulin production in advanced diabetes. Studies to further assess the molecular factors that explain the BMI/obesity-PrCa recurrence relationship are warranted.

Accuracy of prostate measurements on MRI with and without an endorectal coil.

PURPOSE: To assess accuracy of prostate measurements with and without endorectal coil (ERC). MATERIALS AND METHODS: Anteroposterior (AP), transverse (TX) and craniocaudal (CC) measurements were recorded from 49 prostate magnetic resonance images (MRIs) done both with and without ERC. Prostate weight was calculated as follows: AP*TX*CC*π/6. Prostate dimensions and weight were obtained from radical prostatectomy pathology report. RESULTS: After ERC placement, AP decreased by 0.71 cm [95% confidence interval (CI) 0.80-0.61], TX and CC increased by 0.26 cm (95% CI 0.18-0.33) and 0.25 cm (95% CI 0.16-0.35), respectively. Agreement between weight on pathology and MR was excellent: intraclass correlation coefficient (ICC) without ERC=0.96, ICC with ERC=0.90. CONCLUSION: Although ERC distorts measurements and despite a tendency to underestimate the prostate weight, absolute agreement between prostate weight on pathology and MRI is excellent, both with and without ERC.

Outcomes and Management Considerations in Patients on Dialysis Undergoing Laparoscopic Radical Nephrectomy for Renal-Cell Carcinoma.

PURPOSE: To analyze the perioperative outcomes and management considerations in patients with dialysis-dependent end-stage renal disease (ESRD) undergoing laparoscopic radical nephrectomy for renal-cell carcinoma (RCC). METHODS: There were 224 consecutive laparoscopic radical nephrectomies reviewed. Of those, 37 patients with ESRD were identified and compared with 187 patients with sporadic RCC. Evaluable parameters included age, sex, race, side of surgery, medical comorbidities, body mass index, American Society of Anesthesiologist (ASA) scoring, and age adjusted Charlson Comorbidity Index. All complications occurring intraoperatively and within the first 30 days were classified as per the Clavien classification system. Presurgical workup and transplant considerations were evaluated. Demographic and clinical characteristics were compared using Student t tests and chi-square tests for categoric variables. RESULTS: Compared with non-ESRD patients, those with ESRD were younger and had smaller tumors. ASA was significantly higher in the ESRD group (P<0.001). Mean blood loss was similar between ESRD patients and non-ESRD patients. Overall complication rates were higher in patients with ESRD. Pathologic characteristics of ESRD renal masses included a higher proportion of papillary RCC. CONCLUSION: Patients with RCC associated with ESRD tend to have a higher ASA class and lower grade tumors. In addition, this population is at increased risk of surgical complications and more likely to need transfusions. Careful preoperative preparation and intraoperative anesthetic management are crucial to minimize patient morbidity and improve outcomes.

The relationship between visceral obesity and the clinicopathologic features of patients with small renal masses.

INTRODUCTION AND OBJECTIVES: It is well known that adipose tissue plays a key role in the metabolic syndrome. We investigated whether visceral fat (VFA) and or subcutaneous fat (SQF) levels are associated with the tumor phenotype of small renal masses. Additionally, we sought to investigate the relationship between VFA and baseline renal function as measured by glomerular filtration rate. MATERIALS AND METHODS: From 2002 through 2011, 144 patients undergoing minimally invasive partial nephrectomy were retrospectively reviewed by a radiologist for VFA and SQF fat measurements, using standard software. A third parameter, visceral adipose tissue percent (VAT%), was also calculated using the formula: (VAT%=[VFA/VFA+SQF]×100%). We used tertiles of VFA and SQF content to compare demographic and clinical characteristics. We also looked at VFA as a continuous variable. Associations between covariables were analyzed using multivariate logistic regression analysis and odds ratios with 95% confidence intervals. RESULTS: Eighty-one patients had renal-cell carcinoma (RCC) and 30 patients had non-RCC pathology. On multivariate analysis, increasing BMI (p=0.023), VFA (p=0.048), VAT% (p=0.028), and Charlson comorbidity score (p=0.047) were significantly associated with worse preoperative Modification of Diet in Renal Disease (MDRD). In a subset multivariate analysis of the 81 patients with RCC, increasing VFA was statistically associated with worsening Fuhrman grade (p=0.017). CONCLUSIONS: VFA may be linked to the pathophysiology of renal function in patients evaluated for renal masses. Additionally, VFA may be associated with worsening tumor grades in patients with small-volume RCC. Interestingly, SQF did not play such a role. This small study proposes an interesting physiologic link between VFA and the biology of both kidney function and tumor histology. Larger studies are needed to corroborate our findings.