Cesar E. Ercole

Decline in Renal Function after Partial Nephrectomy: Etiology and Prevention

PURPOSE Partial nephrectomy is the reference standard for the management of small renal tumors and is commonly used for localized kidney cancer. A primary goal of partial nephrectomy is to preserve as much renal function as possible. New baseline glomerular filtration rate after partial nephrectomy can have prognostic significance with respect to long-term outcomes. Recent studies provide an increased understanding of the factors that determine functional outcomes after partial nephrectomy as well as preventive measures to minimize functional decline. We review these advances, highlight ongoing controversies and stimulate further research. MATERIALS AND METHODS A comprehensive literature review consistent with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria was performed from January 2006 to April 2014 using PubMed®, Cochrane and Ovid Medline. Key words included partial nephrectomy, renal function, warm ischemia, hypothermia, nephron mass, parenchymal volume, surgical approaches to partial nephrectomy, preoperative and intraoperative imaging, enucleation, hemostatic agents and energy based resection. Relevant reviews were also examined as well as their cited references. An additional Google Scholar search was conducted to broaden the scope of the review. Only English language articles were included in the analysis. The primary outcomes of interest were the new baseline level of function after early postoperative recovery, percent decline in function, potential etiologies and preventive measures. RESULTS Decline in function after partial nephrectomy averages approximately 20% in the operated kidney, and can be due to incomplete recovery from the ischemic insult or loss of nephron mass related to parenchymal excision or collateral damage during reconstruction. Compensatory hypertrophy in the contralateral kidney after partial nephrectomy in adults is marginal and decline in global renal function for patients with 2 kidneys averages about 10%, although there is some variance based on tumor size and location. Irreversible ischemic injury can be minimized by pharmacological intervention or surgical approaches such as hypothermia, limited warm ischemia, or zero or segmental ischemia. Excessive loss of nephron mass can be minimized by improved preoperative or intraoperative imaging, use of a bloodless field, enucleation and vascular microdissection. Hemostatic agents or energy based resection that minimizes the need for parenchymal and capsular suturing can also optimize preservation of the vascularized nephron mass. CONCLUSIONS Our understanding of the decline in renal function after partial nephrectomy has advanced considerably, including better appreciation of its magnitude and impact in various settings, possible etiologies and potential preventive measures. Many controversies persist and this remains an important area of investigation.

Multicenter Assessment of Neoadjuvant Chemotherapy for Muscle-invasive Bladder Cancer

BACKGROUND The efficacy of neoadjuvant chemotherapy (NAC) for muscle-invasive bladder cancer (BCa) was established primarily with methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC), with complete response rates (pT0) as high as 38%. However, because of the comparable efficacy with better tolerability of gemcitabine and cisplatin (GC) in patients with metastatic disease, GC has become the most commonly used regimen in the neoadjuvant setting. OBJECTIVE We aimed to assess real-world pathologic response rates to NAC with different regimens in a large, multicenter cohort. DESIGN, SETTING, AND PARTICIPANTS Data were collected retrospectively at 19 centers on patients with clinical cT2-4aN0M0 urothelial carcinoma of the bladder who received at least three cycles of NAC, followed by radical cystectomy (RC), between 2000 and 2013. INTERVENTION NAC and RC. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The primary outcome was pathologic stage at cystectomy. Univariable and multivariable analyses were used to determine factors predictive of pT0N0 and ≤pT1N0 stages. RESULTS AND LIMITATIONS Data were collected on 935 patients who met inclusion criteria. GC was used in the majority of the patients (n=602; 64.4%), followed by MVAC (n=183; 19.6%) and other regimens (n=144; 15.4%). The rates of pT0N0 and ≤pT1N0 pathologic response were 22.7% and 40.8%, respectively. The rate of pT0N0 disease for patients receiving GC was 23.9%, compared with 24.5% for MVAC (p=0.2). There was no difference between MVAC and GC in pT0N0 on multivariable analysis (odds ratio: 0.89 [95% confidence interval, 0.61-1.34]; p=0.6). CONCLUSIONS Response rates to NAC were lower than those reported in prospective randomized trials, and we did not discern a difference between MVAC and GC. Without any evidence from randomized prospective trials, the best NAC regimen for invasive BCa remains to be determined. PATIENT SUMMARY There was no apparent difference in the response rates to the two most common presurgical chemotherapy regimens for patients with bladder cancer.

Survival and Functional Stability in Chronic Kidney Disease Due to Surgical Removal of Nephrons: Importance of the New Baseline Glomerular Filtration Rate.

BACKGROUND Chronic kidney disease (CKD) can be associated with a higher risk of progression to end-stage renal disease and mortality, but the etiology of nephron loss may modify this. Previous studies suggested that CKD primarily due to surgical removal of nephrons (CKD-S) may be more stable and associated with better survival than CKD due to medical causes (CKD-M). OBJECTIVE We addressed limitations of our previous work with comprehensive control for confounding factors, differentiation of non-renal cancer-related mortality, and longer follow-up for more discriminatory assessment of the impact of CKD-S. DESIGN, SETTING, AND PARTICIPANTS From 1999 to 2008, 4299 patients underwent surgery for renal cancer at a single institution. The median follow-up was 9.4 yr (7.3-11.0). The new baseline glomerular filtration rate (GFR) was defined as the highest GFR between the nadir and 42 d after surgery. Three cohorts were retrospectively evaluated: no CKD (new baseline GFR >60 ml/min/1.73 m(2)); CKD-S (new baseline GFR<60 but preoperative >60 ml/min/1.73 m(2)); and CKD-M/S (new baseline and preoperative GFR both <60 ml/min/1.73 m(2)). Cohort status was permanently set at 42 d after surgery. INTERVENTION Renal surgery. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Decline in renal function (50% reduction in GFR or dialysis), all-cause mortality, and non-renal cancer mortality were examined using a multivariable Cox proportional hazards model. RESULTS AND LIMITATIONS CKD-M/S had a higher incidence of relevant comorbidities and the new baseline GFR was lower. On multivariable analysis (controlling for age, gender, race, diabetes, hypertension, and cardiac disease), CKD-M/S had higher rates of progressive decline in renal function, all-cause mortality, and non-renal cancer mortality when compared to CKD-S and no CKD (hazard ratio [HR] 1.69-2.33, all p<0.05). All-cause mortality was modestly higher for CKD-S than for no CKD (HR 1.19, p=0.030), but renal stability and non-renal cancer mortality were similar for these groups. New baseline GFR of <45 ml/min/1.73 m(2) significantly predicted adverse outcomes. The main limitation is the retrospective design. CONCLUSIONS CKD-S is more stable than CKD-M/S and has better survival, approximating that for no CKD. However, if the new baseline GFR is <45 ml/min/1.73 m(2), the risks of functional decline and mortality increase. These findings may influence counseling for patients with localized renal cell carcinoma and higher oncologic potential when a normal contralateral kidney is present. PATIENT SUMMARY Survival is better for surgically induced chronic kidney disease (CKD) than for medically induced CKD, particularly if the postoperative glomerular filtration rate is ≥45 ml/min/1.73 m(2). Patients with preexisting CKD are at risk of a significant decline in kidney function after surgery, and kidney-preserving treatment should be strongly considered in such cases.

Androgen metabolism in prostate cancer: from molecular mechanisms to clinical consequences

Despite our most vigorous efforts, prostate cancer remains the second leading cause of cancer death in men. Understanding the intricacies of androgen metabolism is vital to finding therapeutic targets, particularly with progression of advanced prostate cancer after initial hormone therapy, where adrenal precursors are involved. Such is the case with castration-resistant prostate cancer, where adrenal androgens, for example, dehydroepiandrosterone, are a source for intratumoural synthesis of dihydrotestosterone. As prostate cancer progresses, androgen metabolism changes due to altered expression of steroidogenic enzymes and mutations in the components of the steroidogenic machinery. These alterations sustain disease and allow progression; mechanistically, they may also enable development of hormone therapy resistance. With the development of the newer agents, abiraterone acetate and enzalutamide, efforts have been made to better define the basis for response and resistance. This work can be carried out in cell lines, animal models, as well as with ex vivo analysis of tissues obtained from patients. Efforts to further elucidate the finer details of the steroidogenic pathway are necessary to move toward a curative paradigm for patients with localised disease at high risk for recurrence.

Presurgical sunitinib reduces tumor size and may facilitate partial nephrectomy in patients with renal cell carcinoma

OBJECTIVE To determine whether presurgical sunitinib reduces primary renal cell carcinoma (RCC) size and facilitates partial nephrectomy (PN). METHODS Data from potential candidates for PN treated with sunitinib with primary RCC in situ were reviewed retrospectively. Primary outcome was reduction in tumor bidirectional area. RESULTS Included were 72 potential candidates for PN who received sunitinib before definitive renal surgery on 78 kidneys. Median primary tumor size was 7.2 cm (interquartile range [IQR]: 5.3-8.7 cm) before and 5.3 cm (IQR: 4.1-7.5 cm) after sunitinib treatment (P<0.0001), resulting in 32% reduction in tumor bidirectional area (IQR: 14%-46%). Downsizing occurred in 65 tumors (83%), with 15 partial responses (19%). Tumor complexity per R.E.N.A.L. score was reduced in 59%, with median posttreatment score of 9 (IQR: 8-10). Predictors of lesser tumor downsizing included clinical evidence of lymph node metastases (P<0.0001), non-clear cell histology (P = 0.0017), and higher nuclear grade (P = 0.023). Surgery was performed for 68 tumors (87%) and was not delayed in any patient owing to sunitinib toxicity. Grade ≥ 3 surgical complications occurred in 5 patients (7%). PN was performed for 49 kidneys (63%) after sunitinib, including 76% of patients without and 41% with metastatic disease (P = 0.0026). PN was completed in 100%, 86%, 65%, and 60% of localized cT1a, cT1b, cT2, and cT3 tumors, respectively. CONCLUSION Presurgical sunitinib leads to modest tumor reduction in most primary RCC, and many patients can be subsequently treated with PN with acceptable morbidity and preserved renal function. A randomized trial is required to definitively determine whether presurgical therapy enhances feasibility of PN.

Zonal NePhRO Scoring System: A Superior Renal Tumor Complexity Classification Model

BACKGROUND Since the advent of the first standardized renal tumor complexity system, many subsequent scoring systems have been introduced, many of which are complicated and can make it difficult to accurately measure data end points. In light of these limitations, we introduce the new zonal NePhRO scoring system. PATIENTS AND METHODS The zonal NePhRO score is based on 4 anatomical components that are assigned a score of 1, 2, or 3, and their sum is used to classify renal tumors. The zonal NePhRO scoring system is made up of the (Ne)arness to collecting system, (Ph)ysical location of the tumor in the kidney, (R)adius of the tumor, and (O)rganization of the tumor. In this retrospective study, we evaluated patients exhibiting clinical stage T1a or T1b who underwent open partial nephrectomy performed by 2 genitourinary surgeons. Each renal unit was assigned both a zonal NePhRO score and a RENAL (radius, exophytic/endophytic properties, nearness of tumor to the collecting system or sinus in millimeters, anterior/posterior, location relative to polar lines) score, and a blinded reviewer used the same preoperative imaging study to obtain both scores. Additional data points gathered included age, clamp time, complication rate, urine leak rate, intraoperative blood loss, and pathologic tumor size. RESULTS One hundred sixty-six patients underwent open partial nephrectomy. There were 37 perioperative complications quantitated using the validated Clavien-Dindo system; their occurrence was predicted by the NePhRO score on both univariate and multivariate analyses (P = .0008). Clinical stage, intraoperative blood loss, and tumor diameter were all correlated with the zonal NePhRO score on univariate analysis only. CONCLUSION The zonal NePhRO scoring system is a simpler tool that accurately predicts the surgical complexity of a renal lesion.

Nephron-sparing surgery for pathological stage T3b renal cell carcinoma confined to the renal vein.

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

Update in the surgical principles and therapeutic outcomes of inguinal lymph node dissection for penile cancer

OBJECTIVES Inguinal lymph node dissection (ILND) for the treatment of metastatic penile squamous cell carcinoma (SCC) has historically been associated with significant morbidity. This review addresses the surgical principles and techniques to decrease its perioperative morbidity, while optimizing its oncologic outcomes. MATERIALS AND METHODS A review of the English scientific literature from 1966 to present was conducted using the PubMed search engine as well as of additional cited works not initially noted in the search using as keywords penile cancer, inguinal lymph node dissection, inguinal lymph node metastasis, morbidity, and complications. RESULTS The contemporary outcomes of ILND in the context of penile cancer have built on the significant contributions made by surgeons and scientists worldwide. In this review, we provide a comprehensive overview of the principles of ILND optimizing oncological outcomes, while minimizing its attributable morbidity. It is hoped this review will serve as a benchmark for clinicians to approach this often highly aggressive tumor phenotype. CONCLUSIONS ILND remains an important diagnostic and therapeutic procedure for patients with penile SCC, as contemporary ILND series have reported a decrease in its associated morbidity, with the potential for further treatment outcomes in years to come. ILND can in appropriately selected patients render them disease-free, thus justifying its associated morbidity.

Functional Recovery From Extended Warm Ischemia Associated With Partial Nephrectomy.

OBJECTIVE To evaluate the impact of extended warm ischemia on incidence of acute kidney injury (AKI) and ultimate functional recovery after partial nephrectomy (PN), incorporating rigorous control for loss of parenchymal mass, and embedded within comparison to cohorts of patients managed with hypothermia or limited warm ischemia. MATERIALS AND METHODS From 2007 to 2014, 277 patients managed with PN had appropriate studies to evaluate changes in function/mass specifically within the operated kidney. Recovery from ischemia was defined as %function saved/%parenchymal mass saved. AKI was based on global renal function and defined as a ≥1.5-fold increase in serum creatinine above the preoperative level. RESULTS Hypothermia was utilized in 112 patients (median = 27 minutes) and warm ischemia in 165 (median = 21 minutes). AKI strongly correlated with solitary kidney (P < .001) and duration (P < .001) but not type (P = .49) of ischemia. Median recovery from ischemia in the operated kidney was 100% (interquartile range [IQR] = 88%-109%) for cold ischemia, with 6 (5%) noted to have <80% recovery from ischemia. For the warm ischemia group, median recovery from ischemia was 91% (IQR = 82%-101%, P < .001 compared with hypothermia), and 34 (21%) had recovery from ischemia <80% (P < .001). For warm ischemia subgrouped by duration <25 minutes (n = 114), 25-35 minutes (n = 35), and >35 minutes (n = 16), median recovery from ischemia was 92% (IQR = 86%-100%), 90% (IQR = 78%-104%), and 91% (IQR = 80%-96%), respectively (P = .77). CONCLUSION Our results suggest that AKI after PN correlates with duration but not with type of ischemia. However, subsequent recovery, which ultimately defines the new baseline glomerular filtration rate, is most reliable with hypothermia. However, most patients undergoing PN with warm ischemia still recover relatively strongly from ischemia, even if extended to 35-45 minutes.

Analysis of Atrophy After Clamped Partial Nephrectomy and Potential Impact of Ischemia.

OBJECTIVE Ischemia is a potential contributor to decline of function after partial nephrectomy (PN), although loss of parenchymal mass related to excision and reconstruction appears to be a more significant factor. However, loss of parenchymal mass could also be due to global effects of ischemia leading to parenchymal atrophy. In this study, we evaluated parenchymal volumes in regions away from the operated site to assess for atrophy. MATERIALS AND METHODS A total of 164 patients undergoing PN for whom detailed analysis of function and parenchymal mass within the operated kidney could be performed were assessed for opposite pole volume (OPV) before and 4-12 months after surgery. Tumor location was required to be ≥2 cm away from the opposite polar line to exclude local effects related to excision or reconstruction. OPV was estimated by software analysis, and the ratio of the estimates (OPV ratio = postoperative OPV to preoperative OPV) was used to assess for atrophy. RESULTS Patient demographics and tumor characteristics were representative of conventional PN populations, and warm ischemia (n = 101; median, 21 minutes) and cold ischemia (n = 63; median, 26 minutes) were applied by surgeon discretion. OPVs before and after PN were 63.2 and 62.5 cm(3), respectively (P = .76). The median OPV ratio was 0.99 suggesting that significant atrophy did not occur. OPV ratio was 0.99 for warm ischemia cases and 0.99 for cold ischemia cases (P = .95). CONCLUSION Limited warm ischemia or hypothermia was not associated with significant parenchymal atrophy after PN, which suggests that parenchymal volume loss in this setting is primarily due to excision or reconstruction.