The Association of Ischemia Type and Duration with Acute Kidney Injury after Robot-Assisted Partial Nephrectomy

BACKGROUND

Acute kidney injury (AKI) after robot-assisted partial nephrectomy (RAPN) is a robust surrogate for chronic kidney disease. The objective of this study was to evaluate the association of ischemia type and duration during RAPN with postoperative AKI.

MATERIALS AND METHODS

We reviewed all patients who underwent RAPN at our institution since 2011. The ischemia types were warm ischemia (WI), selective artery clamping (SAC), and zero ischemia (ZI). AKI was defined according to the Risk Injury Failure Loss End-Stage (RIFLE) criteria. We calculated ischemia time thresholds for WI and SAC using the Youden and Liu indices. Logistic regression and decision curve analyses were assessed to examine the association with AKI.

RESULTS

Overall, 154 patients met the inclusion criteria. Among all RAPNs, 90 (58.4%), 43 (28.0%), and 21 (13.6%) were performed with WI, SAC, and ZI, respectively. Thirty-three (21.4%) patients experienced postoperative AKI. We extrapolated ischemia time thresholds of 17 min for WI and 29 min for SAC associated with the occurrence of postoperative AKI. Multivariable logistic regression analyses revealed that WIT ≤ 17 min (odds ratio [OR] 0.1, p < 0.001), SAC ≤ 29 min (OR 0.12, p = 0.002), and ZI (OR 0.1, p = 0.035) significantly reduced the risk of postoperative AKI.

CONCLUSIONS

Our results confirm the commonly accepted 20 min threshold for WI time, suggest less than 30 min ischemia time when using SAC, and support a ZI approach if safely performable to reduce the risk of postoperative AKI. Selecting an appropriate ischemia type for patients undergoing RAPN can improve short- and long-term functional kidney outcomes.

Pretreatment Risk Stratification for Endoscopic Kidney-sparing Surgery in Upper Tract Urothelial Carcinoma: An International Collaborative Study

BACKGROUND

Several groups have proposed features to identify low-risk patients who may benefit from endoscopic kidney-sparing surgery in upper tract urothelial carcinoma (UTUC).

OBJECTIVE

To evaluate standard risk stratification features, develop an optimal model to identify ≥pT2/N+ stage at radical nephroureterectomy (RNU), and compare it with the existing unvalidated models.

DESIGN, SETTING, AND PARTICIPANTS

This was a collaborative retrospective study that included 1214 patients who underwent ureterorenoscopy with biopsy followed by RNU for nonmetastatic UTUC between 2000 and 2017.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We performed multiple imputation of chained equations for missing data and multivariable logistic regression analysis with a stepwise selection algorithm to create the optimal predictive model. The area under the curve and a decision curve analysis were used to compare the models.

RESULTS AND LIMITATIONS

Overall, 659 (54.3%) and 555 (45.7%) patients had ≤pT1N0/Nx and ≥pT2/N+ disease, respectively. In the multivariable logistic regression analysis of our model, age (odds ratio [OR] 1.02, 95% confidence interval [CI] 1.0-1.03, p = 0.013), high-grade biopsy (OR 1.81, 95% CI 1.37-2.40, p < 0.001), biopsy cT1+ staging (OR 3.23, 95% CI 1.93-5.41, p < 0.001), preoperative hydronephrosis (OR 1.37 95% CI 1.04-1.80, p = 0.024), tumor size (OR 1.09, 95% CI 1.01-1.17, p = 0.029), invasion on imaging (OR 5.10, 95% CI 3.32-7.81, p < 0.001), and sessile architecture (OR 2.31, 95% CI 1.58-3.36, p < 0.001) were significantly associated with ≥pT2/pN+ disease. Compared with the existing models, our model had the highest performance accuracy (75% vs 66-71%) and an additional clinical net reduction (four per 100 patients).

CONCLUSIONS

Our proposed risk-stratification model predicts the risk of harboring ≥pT2/N+ UTUC with reliable accuracy and a clinical net benefit outperforming the current risk-stratification models.

PATIENT SUMMARY

We developed a risk stratification model to better identify patients for endoscopic kidney-sparing surgery in upper tract urothelial carcinoma.

Novel Classification for Upper Tract Urothelial Carcinoma to Better Risk-stratify Patients Eligible for Kidney-sparing Strategies: An International Collaborative Study

BACKGROUND

The European Association of Urology risk stratification dichotomizes patients with upper tract urothelial carcinoma (UTUC) into two risk categories.

OBJECTIVE

To evaluate the predictive value of a new classification to better risk stratify patients eligible for kidney-sparing surgery (KSS).

DESIGN, SETTING, AND PARTICIPANTS

This was a retrospective study including 1214 patients from 21 centers who underwent ureterorenoscopy (URS) with biopsy followed by radical nephroureterectomy (RNU) for nonmetastatic UTUC between 2000 and 2017.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

A multivariate logistic regression analysis identified predictors of muscle invasion (≥pT2) at RNU. The Youden index was used to identify cutoff points.

RESULTS AND LIMITATIONS

A total of 811 patients (67%) were male and the median age was 71 yr (interquartile range 63-77). The presence of non-organ-confined disease on preoperative imaging (p < 0.0001), sessile tumor (p < 0.0001), hydronephrosis (p = 0.0003), high-grade cytology (p = 0.0043), or biopsy (p = 0.0174) and higher age at diagnosis (p = 0.029) were independently associated with ≥pT2 at RNU. Tumor size was significantly associated with ≥pT2 disease only in univariate analysis with a cutoff of 2 cm. Tumor size and all significant categorical variables defined the high-risk category. Tumor multifocality and a history of radical cystectomy help to dichotomize between low-risk and intermediate-risk categories. The odds ratio for muscle invasion were 5.5 (95% confidence interval [CI] 1.3-24.0; p = 0.023) for intermediate risk versus low risk, and 12.7 (95% CI 3.0-54.5; p = 0.0006) for high risk versus low risk. Limitations include the retrospective design and selection bias (all patients underwent RNU).

CONCLUSIONS

Patients with low-risk UTUC represent ideal candidates for KSS, while some patients with intermediate-risk UTUC may also be considered. This classification needs further prospective validation and may help stratification in clinical trial design.

PATIENT SUMMARY

We investigated factors predicting stage 2 or greater cancer of the upper urinary tract at the time of surgery for ureter and kidney removal and designed a new risk stratification. Patients with low or intermediate risk may be eligible for kidney-sparing surgery with close follow-up. Our classification scheme needs further validation based on cancer outcomes.

Functional Outcomes after Local Salvage Therapies for Radiation-Recurrent Prostate Cancer Patients: A Systematic Review

PURPOSE

To assess the rate and severity of functional outcomes after salvage therapy for radiation recurrent prostate cancer.

METHODS

This systematic review of the MEDLINE/PubMed database yielded 35 studies, evaluating salvage radical prostatectomy (RP), brachytherapy (BT), high-intensity focal ultrasound (HIFU) and cryotherapy (CT) after failure of primary radiation therapy. Data on pre- and post-salvage rates and severity of functional outcomes (urinary incontinence, erectile dysfunction, and lower urinary tract symptoms) were collected from each study.

RESULTS

The rates of severe urinary incontinence ranged from 28-88%, 4.5-42%, 0-6.5%, 2.4-8% post salvage RP, HIFU, CT and BT, respectively. The rates of erectile dysfunction were relatively high reaching as much as 90%, 94.6%, 100%, 62% following RP, HIFU, CT and BT, respectively. Nonetheless, the high pre-salvage rates of ED preclude accurate estimation of the effect of salvage therapy. There was an increase in the median IPSS following salvage HIFU, BT and CT ranging from 2.5-3.4, 3.5-12, and 2, respectively. Extended follow-up showed a return-to-baseline IPSS in a salvage BT study. The reported data suffer from selection, reporting, publication and period of study biases, making inter-study comparisons inappropriate.

CONCLUSIONS

local salvage therapies for radiation recurrent PCa affect continence, lower urinary tract symptoms and sexual functions. The use of local salvage therapies may be warranted in the setting of local disease control, but each individual decision must be made with the informed patient in a shared decision working process.

Expression of urokinase-type plasminogen activator system in non-metastatic prostate cancer

PURPOSE

To investigate the prognostic role of expression of urokinase-type plasminogen activator system members, such as urokinase-type activator (uPA), uPA-receptor (uPAR), and plasminogen activator inhibitor-1 (PAI-1), in patients treated with radical prostatectomy (RP) for prostate cancer (PCa).

METHODS

Immunohistochemical staining for uPA system was performed on a tissue microarray of specimens from 3121 patients who underwent RP. Cox regression analyses were performed to investigate the association of overexpression of these markers alone or in combination with biochemical recurrence (BCR). Decision curve analysis was used to assess the clinical impact of these markers.

RESULTS

uPA, uPAR, and PAI-1 were overexpressed in 1012 (32.4%), 1271 (40.7%), and 1311 (42%) patients, respectively. uPA overexpression was associated with all clinicopathologic characteristics of biologically aggressive PCa. On multivariable analysis, uPA, uPAR, and PAI-1 overexpression were all three associated with BCR (HR: 1.75, p < 0.01, HR: 1.22, p = 0.01 and HR: 1.20, p = 0.03, respectively). Moreover, the probability of BCR increased incrementally with increasing cumulative number of overexpressed markers. Decision curve analysis showed that addition of uPA, uPAR, and PAI-1 resulted in a net benefit compared to a base model comparing standard clinicopathologic features across the entire threshold probability range. In subgroup analyses, overexpression of all three markers remained associated with BCR in patients with favorable pathologic characteristics.

CONCLUSION

Overexpression of uPA, uPAR, and PAI-1 in PCa tissue were each associated with worse BCR. Additionally, overexpression of all three markers is informative even in patients with favorable pathologic characteristics potentially helping clinical decision-making regarding adjuvant therapy and/or intensified follow-up.

Association of Smoking Status With Recurrence, Metastasis, and Mortality Among Patients With Localized Prostate Cancer Undergoing Prostatectomy or Radiotherapy: A Systematic Review and Meta-analysis

Importance

Studies investigating the association of cigarette smoking with prostate cancer incidence and outcomes have revealed controversial results.

Objective

To systematically review and analyze the association of smoking status with biochemical recurrence, metastasis, and cancer-specific mortality among patients with localized prostate cancer undergoing primary radical prostatectomy or radiotherapy.

Data Sources

A systematic search of original articles published between January 2000 and March 2017 was performed using PubMed, MEDLINE, Embase, and Cochrane Library databases in March 2017.

Study Selection

Observational studies reporting Cox proportional hazards regression or logistic regression analyses were independently screened.

Data Extraction and Synthesis

This systematic review and meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and the Cochrane Handbook for Systematic Reviews of Interventions. Available multivariable hazard ratios (HRs) and corresponding 95% CIs were included in quantitative analysis. A risk-of-bias assessment was completed for nonrandomized studies.

Main Outcomes and Measures

Prespecified outcomes of interest were biochemical recurrence, metastasis, and cancer-specific mortality.

Results

A total of 5157 reports were identified, of which 16 articles were selected for qualitative analysis and 11 articles were selected for quantitative analysis. All included studies were observational and nonrandomized and comprised a total of 22 549 patients. Overall, 4202 patients (18.6%) were current smokers. The overall median follow-up was 72 months. Current smokers had a statistically significantly higher risk of biochemical recurrence (HR, 1.40; 95% CI, 1.18-1.66; P < .001 [10 studies]), as did former smokers (HR, 1.19; 95% CI, 1.09-1.30; P < .001 [7 studies]). Current smokers were also at a higher risk of metastasis (HR, 2.51; 95% CI, 1.80-3.51; P < .001 [3 studies]) and cancer-specific mortality (HR, 1.89; 95% CI, 1.37-2.60; P < .001 [5 studies]), whereas former smokers were not (metastasis: HR, 1.61; 95% CI, 0.65-3.97; P = .31 [2 studies]; cancer-specific mortality: HR, 1.05; 95% CI, 0.81-1.37; P = .70 [4 studies]).

Conclusions and Relevance

Current smokers at the time of primary curative treatment for localized prostate cancer are at higher risk of experiencing biochemical recurrence, metastasis, and cancer-specific mortality.

Development and external validation of a pathological nodal staging score for patients with clear cell renal cell carcinoma

OBJECTIVES

To develop and externally validate a model that quantifies the likelihood that a pathologically node-negative patient with clear cell renal cell carcinoma (cRCC) has, indeed, no lymph node metastasis (LNM).

PATIENTS AND METHODS

Data from 1389 patients treated with radical nephrectomy (RN) and lymph node dissection (LND) were analyzed. For external validation, we used data from 2270 patients in the Surveillance, Epidemiology and End Results (SEER) database. We estimated the sensitivity of pathologic nodal staging using a beta-binomial model and developed a pathological nodal staging score (pNSS), which represents the probability that a patient is correctly staged as node negative as a function of the number of examined lymph nodes (LNs).

RESULTS

The mean and median number of LNs removed were 7.0 and 5.0 (standard deviation, SD 6.6; interquartile range, IQR 7.0) in the development cohort and 5.6 and 2.0 (SD 8.6, IQR 5.0) in the validation cohort, respectively. The probability of missing a positive LN decreased with increasing number of LNs examined. In both the validation and the development cohort, the number of LNs needed for correctly staging a patient as node negative increased with higher pathological tumor stage and Fuhrman grade.

CONCLUSIONS

The number of examined LNs needed for adequate nodal staging in cRCC depends on pathological tumor stage and Fuhrman grade. We developed here and then externally validated a pNSS, which could help to refine patient counseling, decision-making regarding risk-stratified surveillance regimens and inclusion criteria for clinical trials of adjuvant therapy.

Comparison of perioperative complications and health-related quality of life between robot-assisted and open radical cystectomy: A systematic review and meta-analysis

To compare postoperative complications and health‐related quality of life of patients undergoing robot‐assisted radical cystectomy with those of patients undergoing open radical cystectomy. A systematic search was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement. A pooled meta‐analysis was carried out to assess the differences between robot‐assisted radical cystectomy and open radical cystectomy according to randomized and non‐randomized comparative studies, respectively. We identified six randomized comparative studies and 31 non‐randomized comparative studies. Most robot‐assisted radical cystectomy patients were treated with extracorporeal urinary diversion. Robot‐assisted radical cystectomy was associated with longer operative times, and lower blood loss and transfusion rates compared with open radical cystectomy in both randomized comparative studies and non‐randomized comparative studies. There was no significant difference between robot‐assisted radical cystectomy and open radical cystectomy in the rate of patients with any or major complications within 90 days both in randomized comparative studies and non‐randomized comparative studies. Non‐randomized comparative studies reported a lower rate of complications at 30 days, mortality at 90 days and length of stay for patients treated with robot‐assisted radical cystectomy, which were not confirmed in randomized comparative studies. Additionally, there were no differences in postoperative quality of life score assessment at 3 and 6 months between robot‐assisted radical cystectomy and open radical cystectomy. Robot‐assisted radical cystectomy is associated with less blood loss and lower transfusion rates. There is no difference in complications, length of stay, mortality, and quality of life between robot‐assisted radical cystectomy and open radical cystectomy. Data from non‐randomized comparative studies favor perioperative outcomes in robot‐assisted radical cystectomy patients, the failure to confirm in randomized comparative studies, likely due to bias in study design and reporting. Further randomized comparative studies comparing postoperative complications and quality of life between robot‐assisted radical cystectomy with intracorporeal urinary diversion and open radical cystectomy are required to assess potential differences between these two surgical approaches.

Prognostic Value of Concomitant Carcinoma In Situ in the Radical Cystectomy Specimen: A Systematic Review and Meta-Analysis

PURPOSE

We investigated the prognostic impact of concomitant carcinoma in situ in radical cystectomy specimens.

MATERIALS AND METHODS

We performed a systematic review and meta-analysis using MEDLINE®, Scopus®, Web of Science™ and The Cochrane Library to identify eligible studies published until October 2017. Studies were eligible for analysis if they compared patients with concomitant carcinoma in situ in radical cystectomy specimens for bladder cancer to patients without concomitant carcinoma in situ to determine its value to prognosticate overall mortality, recurrence-free survival, cancer specific mortality and ureteral involvement using multivariable analysis. The protocol for this systematic review was registered in PROSPERO (Prospective Register of Systematic Reviews, CRD42018086539) and is available in full on the University of York website.

RESULTS

Overall 23 studies published between 2006 and 2017 including a total of 20,647 patients were selected for the systematic review and meta-analysis. Concomitant carcinoma in situ was reported in 39.4% of radical cystectomy specimens. In studies analyzing all patients the presence of concomitant carcinoma in situ was not associated with overall mortality (pooled HR 0.92, 0.77-1.10), recurrence-free survival (pooled HR 1.06, 0.99-1.13) or cancer specific mortality (pooled HR 1.00, 0.93-1.07). It was associated with ureteral involvement (pooled OR 4.51, 2.59-7.84). On subanalysis of studies restricted to patients with organ confined bladder cancer at radical cystectomy concomitant carcinoma in situ was associated with worse recurrence-free survival (pooled HR 1.57, 1.12-2.21) and cancer specific mortality (pooled HR 1.51, 1.001-2.280).

CONCLUSIONS

Concomitant carcinoma in situ is significantly associated with ureteral involvement in patients treated with radical cystectomy. In patients with organ confined disease concomitant carcinoma in situ in the radical cystectomy specimen is a prognosticator of recurrence-free survival and cancer specific mortality.

Comparative Effectiveness in Perioperative Outcomes of Robotic versus Open Radical Cystectomy: Results from a Multicenter Contemporary Retrospective Cohort Study

BACKGROUND

The comparative effectiveness of robotic-assisted radical cystectomy (RARC) versus open radical cystectomy (ORC) in terms of perioperative outcomes is still a matter of debate affecting payors, physicians, and patients.

OBJECTIVE

To evaluate comparative perioperative and longer-term morbidity of RARC versus ORC in a multicenter contemporary retrospective cohort of patients.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective multicenter study included patients with bladder cancer treated with radical cystectomy at 10 academic centers between 2000 and 2017.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Intraoperative outcomes including blood loss and operative time as well as postoperative outcomes including time to discharge, complication, readmission, reoperation, and mortality rates at 30 and 90 d were assessed. Multiple imputation and inverse probability of treatment weighting (IPTW) were used. IPTW-multivariable-adjusted regression and logistic analyses were performed to evaluate the associations of RARC versus ORC with perioperative outcomes at 30 and 90 d.

RESULTS AND LIMITATIONS

Overall, 1887 patients (1197 RARC and 690 ORC) were included in the study. After IPTW-adjusted analysis, no differences between the groups in terms of preoperative characteristics were observed. RARC was associated with lower blood loss (p<0.001), shorter length of stay (p<0.001), and longer operative time (p=0.007). On IPTW-adjusted multivariable logistic regression analyses, no differences in terms of 30- and 90-d complications, reoperation, and mortality rates were observed. RARC was independently associated with a higher readmission rate at both 30 and 90 d. Limitations are mainly related to the retrospective nature of the study.

CONCLUSIONS

While RARC was associated with less blood loss and shorter hospital stay, it also led to longer operation times and more readmissions. There were no differences in 30- and 90-d complications. Because there are no apparent differences in safety between ORC and RARC in expert centers, differences in oncologic and cost-effectiveness outcomes are likely to drive decision making regarding RARC utilization.

PATIENT SUMMARY

In this study we investigated the differences between RARC and ORC in terms of perioperative outcomes. We found no difference in early and late complications. We concluded that, to date, differences in oncologic and cost-effectiveness outcomes should drive decision making regarding RARC utilization.

A systematic review and meta-analysis of the impact of lymphovascular invasion in bladder cancer transurethral resection specimens

The aim of the present review was to assess the prognostic impact of lymphovascular invasion (LVI) in transurethral resection (TUR) of bladder cancer (BCa) specimens on clinical outcomes. A systematic review and meta-analysis of the available literature from the past 10 years was performed using MEDLINE, EMBASE and Cochrane library in August 2017. The protocol for this systematic review was registered on PROSPERO (Central Registration Depository: CRD42018084876) and is available in full on the University of York website. Overall, 33 studies (including 6194 patients) evaluating the presence of LVI at TUR were retrieved. LVI was detected in 17.3% of TUR specimens. In 19 studies, including 2941 patients with ≤cT1 stage only, LVI was detected in 15% of specimens. In patients with ≤cT1 stage, LVI at TUR of the bladder tumour (TURBT) was a significant prognostic factor for disease recurrence (pooled hazard ratio [HR] 1.97, 95% CI: 1.47-2.62) and progression (pooled HR 2.95, 95% CI: 2.11-4.13), without heterogeneity (I² = 0.0%, P = 0.84 and I² = 0.0%, P = 0.93, respectively). For patients with cT1-2 disease, LVI was significantly associated with upstaging at time of radical cystectomy (pooled odds ratio 2.39, 95% CI: 1.45-3.96), with heterogeneity among studies (I² = 53.6%, P = 0.044). LVI at TURBT is a robust prognostic factor of disease recurrence and progression in non-muscle invasive BCa. Furthermore, LVI has a strong impact on upstaging in patients with organ-confined disease. The assessment of LVI should be standardized, reported, and considered for inclusion in the TNM classification system, helping clinicians in decision-making and patient counselling.

Progressive tissue biomarker profiling in non-muscle-invasive bladder cancer

INTRODUCTION

The recurrence rate of non-muscle-invasive bladder cancer (NMIBC) is up to 60% within the first year of therapy. Accurate risk stratification is necessary for patient counselling, follow-up scheduling and individualized therapeutic decision making. Current prognostic models rely on clinicopathologic features, but their discrimination remains limited when in external cohorts. Despite intense efforts regarding the value of biomarkers in prognosticating outcomes in NMIBC, clinical utility remains suboptimal. It is clear that a single biomarker is not enough for the prediction of disease recurrence. Therefore, panels of non-redundant biomarkers have been created and integrated in clinical prognostic model further research relying on high throughput technologies is required. Areas covered: We performed a systematic research of the English-language literature on tissue biomarkers for prediction of NMIBC outcomes up to December 2017. Expert commentary: Despite the essential milestones achieved in our knowledge and understanding of the molecular biology underlying NMIBC, no biomarker has been implemented together with clinical feature in clinical practice. Integration of such biomarkers into predictive and prognostic model could, however, improve our accuracy, thereby paving the way for personalized medicine in the management of NMIBC.

A systematic review and meta-analysis of lymphovascular invasion in patients treated with radical cystectomy for bladder cancer

PURPOSE

Lymphovascular invasion (LVI) is an important step in bladder cancer cell dissemination. We aimed to perform a systematic review and meta-analysis of the literature to assess the prognostic value of LVI in radical cystectomy (RC) specimens.

PATIENTS AND METHODS

A systematic review and meta-analysis of the last 10 years was performed using the MEDLINE, EMBASE, and the Cochrane libraries in July 2017. The analyses were performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement.

RESULTS

We retrieved 65 studies (including 78,107 patients) evaluating the effect of LVI on oncologic outcomes in patients treated with RC. LVI was reported in 35.4% of patients. LVI was associated with disease recurrence (pooled hazard ratio [HR] = 1.57; 95% CI: 1.45-1.70) and cancer-specific mortality (CSM) (pooled HR = 1.59; 95% CI: 1.48-1.73) in all studies regardless of tumor stage and node status (pT1-4 pN0-2). LVI was associated with recurrence and CSM in patients with node-negative bladder cancer (BC). In patients with node-negative BC, LVI rate increased and was associated with worse oncologic outcome. LVI had a lower but still significant association with disease recurrence and CSM in node-positive BC.

CONCLUSIONS

LVI is a strong prognostic factor of worse prognosis in patients treated with RC for bladder cancer. This association is strongest in node-negative BC, but it is also in node-positive BC. LVI should be part of all pathological reporting and could provide additional information for treatment-decision making regarding adjuvant therapy after RC.

The impact of moderate wine consumption on the risk of developing prostate cancer

Objective

To investigate the impact of moderate wine consumption on the risk of prostate cancer (PCa). We focused on the differential effect of moderate consumption of red versus white wine.

Design

This study was a meta-analysis that includes data from case–control and cohort studies.

Materials and methods

A systematic search of Web of Science, Medline/PubMed, and Cochrane library was performed on December 1, 2017. Studies were deemed eligible if they assessed the risk of PCa due to red, white, or any wine using multivariable logistic regression analysis. We performed a formal meta-analysis for the risk of PCa according to moderate wine and wine type consumption (white or red). Heterogeneity between studies was assessed using Cochrane’s Q test and I² statistics. Publication bias was assessed using Egger’s regression test.

Results

A total of 930 abstracts and titles were initially identified. After removal of duplicates, reviews, and conference abstracts, 83 full-text original articles were screened. Seventeen studies (611,169 subjects) were included for final evaluation and fulfilled the inclusion criteria. In the case of moderate wine consumption: the pooled risk ratio (RR) for the risk of PCa was 0.98 (95% CI 0.92–1.05, p=0.57) in the multivariable analysis. Moderate white wine consumption increased the risk of PCa with a pooled RR of 1.26 (95% CI 1.10–1.43, p=0.001) in the multi-variable analysis. Meanwhile, moderate red wine consumption had a protective role reducing the risk by 12% (RR 0.88, 95% CI 0.78–0.999, p=0.047) in the multivariable analysis that comprised 222,447 subjects.

Conclusions

In this meta-analysis, moderate wine consumption did not impact the risk of PCa. Interestingly, regarding the type of wine, moderate consumption of white wine increased the risk of PCa, whereas moderate consumption of red wine had a protective effect. Further analyses are needed to assess the differential molecular effect of white and red wine conferring their impact on PCa risk.

Repeat Transurethral Resection in Non-muscle-invasive Bladder Cancer: A Systematic Review

CONTEXT

Initial treatment for most bladder cancers (BCs) involves transurethral resection (TUR) or tumours. Often more cancer is found after the initial treatment in around half of patients, requiring a second resection. Repeat transurethral resection (reTUR) is recommended for high-risk, non-muscle-invasive bladder cancer (NMIBC) to remove any residual disease and improve cancer outcomes.

OBJECTIVE

To systematically review the practice and therapeutic benefit of an early reTUR for high-risk NMIBC.

EVIDENCE ACQUISITION

A systematic review of original articles was performed using PubMed/Medline and Web of Science databases in December 2016 (initial) and October 2017 (final). We searched the references of included papers.

EVIDENCE SYNTHESIS

We screened 15 209 manuscripts and selected 31 detailing 8409 persons with high-grade Ta and T1BC for inclusion. Detrusor muscle was found at initial TUR histology in 30-100% of cases. Residual tumour at reTUR was found in 17-67% of patients following Ta and in 20-71% following T1 cancer. Most residual tumours (36-86%) were found at the original resection site. Upstaging occurred in 0-8% (Ta to ≥T1) and 0-32% (T1 to ≥T2) of cases. Conflicting data report the impact of reTUR on subsequent recurrence and cancer-specific mortality. Recurrence for Ta was 16% in the reTUR group versus 58% in the non-reTUR group. For T1, recurrence ranged from 18% to 56%, but no clear trend was identified between reTUR and control. No clear relationship between reTUR and progression was found for Ta, although for T1 rates were higher in the non-reTUR group in series with control populations (5/6 studies). Overall mortality was slightly reduced in the reTUR group in two studies with controls (22-30% vs 26-36% [no reTUR]).

CONCLUSIONS

Residual tumour is common after TUR for high-risk NMIBC. The reTUR helps in the diagnosis of this residual cancer and may improve outcomes for cancers initially staged as T1.

PATIENT SUMMARY

Some bladder cancers (BCs) are aggressive but confined to the bladder surface. Initial treatment includes endoscopic resection. More cancer is found after the initial treatment in approximately half of patients. In the aggressive but confined group of BC, a second resection, a few weeks after the first, may help find this residual cancer and improve outcomes, although the evidence quality for this is weak.

Accurate prediction of progression to muscle-invasive disease in patients with pT1G3 bladder cancer: A clinical decision-making tool

PURPOSE

To improve current prognostic models for the selection of patients with T1G3 urothelial bladder cancer who are more likely to fail intravesical therapy and progress to muscle-invasive bladder cancer (MIBC).

MATERIALS AND METHODS

We performed a retrospective analysis of 1,289 patients with pT1G3 urothelial bladder cancer who were treated with transurethral resection of the bladder (TURB) and adjuvant intravesical bacillus-Calmette-Guérin (BCG). Random-split sample data and competing-risk regression were used to identify the independent impact of lymphovascular invasion (LVI) and variant histology (VH) on progression to MIBC. We developed a nomogram for predicting patient-specific probability of disease progression at 2 and 5 years after TURB. Decision curve analysis (DCA) was performed to evaluate the clinical benefit associated with the use of our nomogram.

RESULTS

In the development cohort, within a median follow-up of 51.6 months (IQR: 19.3-92.5), disease progression occurred in 89 patients (13.8%). A total of 84 (13%) patients were found to have VH and 57 (8.8%) with LVI at TURB. Both factors were independently associated with disease progression on multivariable competing-risk analysis (HR: 4.4; 95% CI: 2.8-6.9; P<0.001 and HR: 3.5; 95% CI: 2.1-5.8; P<0.001, respectively). DCA showed superior net benefits for the nomogram within a threshold probability of progression between 5% and 55%. Limitations are inherent to the retrospective design.

CONCLUSIONS

We demonstrated the clinical value of the integration of LVI and VH in a prognostic model for the prediction of MIBC. Indeed, our tool provides superior individualized risk estimation of progression facilitating decision-making regarding early RC.

Genetic determinants for chemo- and radiotherapy resistance in bladder cancer

Bladder cancer (BCa) is burdened by high rates of chemo- and radio-resistance. We reviewed and summarized the current evidence regarding the genetic determinants of resistance in patients treated with chemotherapy and/or radiotherapy (RT) for BCa. Genetic heterogeneity may preexist to treatment arising with tumorigenesis or increasing progressively during the treatment. Several biological pathways seem to be involved in the cellular response to treatment. These pathways comprehend mechanisms leading to modify the intracellular concentration of the drug, mechanisms leading to increase the repair of DNA damage caused by the treatment, mechanisms leading to increase cell survival, despite DNA damage, acting on the signaling pathways affecting apoptosis, mechanisms promoting autophagy. In the present review, we focused on the genetic determinants of resistance affecting the aforementioned mechanisms.

Oncologic Effect of Cumulative Smoking Exposure in Patients Treated With Salvage Radical Prostatectomy for Radiation-recurrent Prostate Cancer

INTRODUCTION

The purpose of the present study was to investigate the association of smoking with biochemical recurrence (BCR) and metastasis in radiation-recurrent prostate cancer (PCa) patients undergoing salvage radical prostatectomy (SRP).

PATIENTS AND METHODS

A total of 214 patients treated with SRP for radiation-recurrent PCa in 5 tertiary referral centers were included from January 2007 to December 2015. Kaplan-Meier analyses were used to assess the time to BCR and metastasis. Pre- and postoperative multivariable Cox proportional hazard regression models were fitted.

RESULTS

Overall, 120 (56.1%), 49 (22.9%), and 45 (21%) patients were never, former, and current smokers, respectively. Low-, medium-, and high-cumulative smoking exposure was registered in 59.8%, 16.4%, and 23.8% of cases, respectively. Patients with high cumulative smoking exposure had a significantly greater rate of a pathologic Gleason score of ≥ 8 (P = .01) and extracapsular extension (P = .004). Smoking status, cumulative smoking exposure, intensity, and duration were significantly associated with BCR-free survival (P < .001 for all). Smoking status, cumulative smoking exposure, and smoking intensity were significantly associated with metastasis-free survival (P = .03 for all). High cumulative smoking exposure was independently associated with BCR in both pre- (hazard ratio, 2.23; P = .001) and postoperative (hazard ratio, 1.64; P = .04) multivariable models adjusted for the effects of established clinicopathologic features. Smoking cessation did not affect either BCR- or metastasis-free survival (P = .56 and P = .40, respectively).

CONCLUSION

High cumulative smoking exposure was associated with the biologic and clinical aggressiveness of PCa in patients treated with SRP for radiation-recurrent disease. Smoking is a modifiable risk factor that detrimentally affected the outcomes, even in patients with advanced PCa.

Comparison of the EORTC tables and the EAU categories for risk stratification of patients with nonmuscle-invasive bladder cancer

PURPOSE

To characterize outcomes of patients with TaT1 urothelial carcinoma of the bladder stratified by the European Association of Urology (EAU) categories and to compare them with European Organization for Research and Treatment of Cancer (EORTC) risk groups to assess the rate and effect of reclassification.

PATIENTS AND METHODS

A multi-institutional database of 5,122 patients with TaT1 urothelial carcinoma of the bladder who underwent transurethral resection of the bladder with or without adjuvant therapy at 8 institutions between 1996 and 2007. Multivariable Cox-regression analyses addressed factors associated with disease recurrence and progression. The net reclassification index was used to compare the performance of the EAU categories with the EORTC scoring system.

RESULTS

Of 5,122 patients, 632 (12.3%), 2,302 (45.0%), and 2,188 (42.7%) were assigned to the low-, intermediate-, and high-risk EAU category, respectively. Within a median follow-up of 62 months (interquartile range: 27-97), 2,365 (46.2%) and 516 (10.1%) patients experienced disease recurrence and progression, respectively. In multivariable Cox-regression analyses, EAU intermediate- and high-risk categories were associated with a higher risk of disease recurrence (P<0.001) and progression (P<0.001) compared to low-risk patients. Application of the EAU categories reclassified 1,940 (37.9%) patients into a higher risk group for recurrence. Likewise, 602 (11.8%) patients were reclassified to a higher and 278 (5.4%) to a lower risk group for progression. The net reclassification index of the EAU risk stratification was 0.1% (95% CI: -3.1% to 3.2%) for recurrence and 10.1% (95% CI: -8.0% to 12.0%) for progression, respectively.

CONCLUSIONS

Compared to EORTC risk stratification, the EAU categories reclassifies 37.9% patients into a higher risk group of recurrence and 11.8% into a higher risk of progression. However, the novel risk stratification assigns most patients to the same treatment as the more complex EORTC tables and can be regarded as an alternative tool for treatment decision-making.

External Validation of the Pathologic Nodal Staging Score for Prostate Cancer: A Population-based Study

BACKGROUND

We sought to externally validate our pathologic nodal staging score (pNSS) model, which allows for quantification of the likelihood that a pathologically node-negative patient will not have lymph node (LN) metastasis after radical prostatectomy for prostate cancer (PCa) in a population-based cohort.

PATIENTS AND METHODS

We analyzed data from 50,598 patients treated with radical prostatectomy and pelvic LN dissection using the Surveillance, Epidemiology, and End Results database. We estimated the sensitivity of pathologic nodal staging using a β-binomial model and developed a novel pNSS model, which represents the probability that a patient's PCa has been correctly staged as node negative as a function of the number of examined LNs. These findings were compared against those from the original cohort of 7135 patients.

RESULTS

The mean and median number of LNs removed was 6.5 and 5, respectively (range, 1-89; interquartile range, 2-8), and 96.9% of the patients (n = 49,020) had stage pN0. Similar to the original cohort, the probability of missing a positive LN decreased with the increasing number of LNs examined. In both the validation and the original cohort, the number of LNs needed to correctly stage a patient's disease as node negative increased with more advanced tumor stage, higher Gleason sum, positive surgical margins, and higher preoperative prostate-specific antigen levels.

CONCLUSION

We have confirmed that the number of examined LNs needed for adequate nodal staging in PCa depends on the pathologic tumor stage, Gleason sum, surgical margins status, and preoperative prostate-specific antigen. We externally validated our pNSS in a population-based cohort, which could help to refine decision-making regarding the administration of adjuvant therapy.

Prognostic Role of N-cadherin Expression in Patients With Invasive Bladder Cancer

BACKGROUND

We assessed the role of N-cadherin as a prognostic biomarker in patients with invasive bladder cancer (BCa) who had undergone radical cystectomy (RC).

PATIENTS AND METHODS

The present retrospective single-center study included 433 BCa patients who had undergone RC and bilateral lymph node dissection. Formalin-fixed paraffin tissue microarrays were stained with an anti-N-cadherin monoclonal mouse antibody. N-cadherin expression was considered positive if any immunoreactivity was detected. Multivariable Cox regression models were created to evaluate the prognostic effect of N-cadherin on survival.

RESULTS

N-cadherin expression was observed in 189 patients (43.7%). It was associated with advanced pathologic stage (P = .001) and lymph node metastasis (P < .001). During a median follow-up period of 10.6 years, N-cadherin expression was associated with worse recurrence-free survival, overall survival, and cancer-specific survival (P < .001, P = .001, and P < .001, respectively). On multivariable analysis adjusted for the effects of standard clinicopathologic features, N-cadherin expression retained its association with worse recurrence-free survival (hazard ratio, 1.41; 95% confidence interval, 1.02-1.92; P = .032) but not cancer-specific survival (P = .07) and overall survival (P = .3).

CONCLUSION

N-cadherin was expressed in approximately 40% of patients with invasive BCa. Its expression was associated with features of biologically and pathologically adverse disease and worse recurrence-free survival. N-cadherin could be a part of a marker panel to help clinical decision-making and therapy for BCa.

Is transurethral resection alone enough for the diagnosis of histological variants? A single-center study

INTRODUCTION

To evaluate incidence of histological variants and grade agreement between transurethral resection (TUR) and radical cystectomy (RC) in patients with bladder cancer.

METHODS

A total of 779 patients treated with TUR and subsequently with RC between 1990 and 2013 at a single center were analyzed retrospectively. Variant histology classifications used in our analyses were sarcomatoid, small cell, squamous, or micropapillary. Grade agreement was calculated using the Cohen kappa coefficient. Logistic regression analyses were built to predict adverse pathologic features from histological variants at TUR.

RESULTS

Considering TUR, 213 (27.3%) patients were diagnosed with histological variants. Of these, 2.1% (n = 16) were found with sarcomatoid variant, 1.7% (n = 13) with small cell, 7.1% (n = 55) with squamous, 12.5% (n = 97) with micropapillary. Considering RC, 212 (27.2%) patients were diagnosed with histological variants. Poor agreement was found considering micropapillary variant and the presence of a histological variant in general (0.11 and 0.27, respectively). Intermediate agreement was found analyzing the presence of sarcomatoid, small cell, and squamous variants (0.43, 0.61, and 0.61, respectively). Small cell carcinoma at TUR was found associated with an increased risk of harboring positive soft tissue surgical margin (odds ratio = 2.08; CI: 1.27-3.41; P = 0.03).

CONCLUSIONS

One out of our patients with bladder cancer was diagnosed with a histological variant either at TUR and RC. We found poor agreement between TUR and RC. Our findings highlight that TUR alone is not sufficient to accurately evaluate the presence of histological variants that may have an effect on treatment and survival outcomes.

Prognostic role of N-cadherin expression in patients with non-muscle-invasive bladder cancer

PURPOSE

To assess the role of N-cadherin as a prognostic biomarker in patients with non-muscle-invasive bladder cancer (NMIBC) treated with transurethral resection with or without adjuvant intravesical therapy.

PATIENTS AND METHODS

Immunohistochemistry using monoclonal mouse antibody was used to evaluate the expression status of N-cadherin in 827 patients with NMIBC. N-cadherin was considered positive if any immunoreactivity with membranous staining was detected. Multivariable Cox regression models were performed to evaluate the prognostic effect of N-cadherin on survival outcomes.

RESULTS

N-cadherin expression was observed in 333 patients (40.3%); it was associated with pT1 stage and high tumor grade (both were P<0.001). Median follow-up was 55 months (interquartile range: 18-106). On multivariable Cox regression analyses that adjusted for the effect of the standard clinicopathologic features, N-cadherin expression remained associated with recurrence-free survival (P = 0.007) but not progression-free survival (P = 0.3), cancer-specific survival (P = 0.2), or overall survival (P = 0.9). Adding N-cadherin to a model for prediction of disease recurrence modestly improved its discrimination from 72.8% to 73.4%.

CONCLUSION

N-cadherin is expressed in approximately 2/5 patients with NMIBC. Its expression is associated with adverse pathological features and higher risk of disease recurrence but not progression. N-cadherin could be incorporated in predictive tools to assist in recurrence prediction helping thereby in patient selection regarding adjuvant therapies and follow-up planning.

Impact of Intra- and Postoperative Blood Transfusion on the Incidence, Timing, and Pattern of Disease Recurrence After Radical Cystectomy

BACKGROUND

The administration of blood transfusion (BT) has been associated with a decrease in survival expectancies in patients treated with radical cystectomy (RC), as a consequence of the immunosuppressive effect mediated by BT. We sought therefore to evaluate if the usage of BT may influence the risk and pattern location of distant recurrences after RC, which may be influenced by this effect.

METHODS

Data from 2 independent cohorts of consecutive patients with bladder cancer treated with RC were analyzed. Distant recurrence included all recurrence locations outside of the true pelvis, such as lung, liver, bone, extra pelvic lymph nodes, peritoneal, or brain recurrences. Cox regression analyses evaluating the risk of developing distant recurrence after RC were built.

RESULTS

In the testing cohort, composed of 1081 patients, 41.2% received a perioperative BT. Within a median follow-up of 52 months (interquartile range, 44-61 months), 277 (25.6%) patients experienced a distant recurrence. In the validation cohort, composed of 433 patients, 42.3% received perioperative BT within a median follow-up of 83 months, and 127 (28.3%) patients experienced distant recurrence. On multivariable analyses predicting distant recurrences, BT was not associated with the risk of distant recurrence stratified by location and time (within first year or later after RC; all P ≥ .2) in both cohorts.

CONCLUSIONS

BT administration was not associated with a different pattern, timing, or rate of distant recurrences in patients when compared with those who did not receive BT. New data are needed to investigate the mechanisms behind the association between BT and survival in RC patients.

Management of muscle invasive, locally advanced and metastatic urothelial carcinoma of the bladder: a literature review with emphasis on the role of surgery

Locally advanced (T3b, T4 and N1-N3) and metastatic urothelial bladder cancer (BCa) is a lethal disease with poor survival outcomes. Combination chemotherapy remains the treatment of choice in patients with metastatic disease and an important part of treatment in addition to radical cystectomy (RC) in patients with locally advanced tumour. Approximately half of patients who underwent RC for muscle invasive BCa relapse after surgery with either local recurrence or distant metastasis. This review focuses on the management of muscle invasive, locally advanced and metastatic BCa with emphasis on the role of surgery; to summarize the current knowledge in order to enhance clinical decision-making and counselling process.

Changes of cerebral white matter in patients suffering from Pantothenate Kinase-Associated Neurodegeneration (PKAN): A diffusion tensor imaging (DTI) study

BACKGROUND

To look for microstructural white matter alterations in patients with dystonia due to Pantothenate Kinase-Associated Neurodegeneration.

MATERIAL AND METHODS

We examined 21 genetically confirmed patients and an age-matched group of 21 healthy controls by diffusion tensor imaging. Evaluation of data was performed by tract-based spatial statistics analysis and a voxel-wise comparison of calculated maps of fractional anisotropy. Findings were compared between groups and correlated to the dystonia score of the Burke-Fahn-Marsden Scale (p ≤ 0.05).

RESULTS

Patients showed reductions of fractional anisotropy mainly in the periventricular substance surrounding the third ventricle, in the medial part of both putamina and in the frontal white matter including the anterior limbs of the internal capsules and the corpus callosum. Infratentorially, the cerebellar white matter and dorsal parts of the pons and medulla were affected.

CONCLUSION

In addition to cortical grey matter changes, we now have a second structural finding pointing to a more widespread affection of cerebral tissue in PKAN dystonia than just the lesion and iron accumulation in the globus pallidus.

NAA and NAAG variation in neuronal activation during visual stimulation

N-acetyl-aspartyl-glutamate (NAAG) and its hydrolysis product N-acetyl-aspartate (NAA) are among the most important brain metabolites. NAA is a marker of neuron integrity and viability, while NAAG modulates glutamate release and may have a role in neuroprotection and synaptic plasticity. Investigating on a quantitative basis the role of these metabolites in brain metabolism in vivo by magnetic resonance spectroscopy (MRS) is a major challenge since the main signals of NAA and NAAG largely overlap. This is a preliminary study in which we evaluated NAA and NAAG changes during a visual stimulation experiment using functional MRS. The paradigm used consisted of a rest period (5 min and 20 s), followed by a stimulation period (10 min and 40 s) and another rest period (10 min and 40 s). MRS from 17 healthy subjects were acquired at 3T with TR/TE = 2000/288 ms. Spectra were averaged over subjects and quantified with LCModel. The main outcomes were that NAA concentration decreased by about 20% with the stimulus, while the concentration of NAAG concomitantly increased by about 200%. Such variations fall into models for the energy metabolism underlying neuronal activation that point to NAAG as being responsible for the hyperemic vascular response that causes the BOLD signal. They also agree with the fact that NAAG and NAA are present in the brain at a ratio of about 1:10, and with the fact that the only known metabolic pathway for NAAG synthesis is from NAA and glutamate.

Establishment of a protocol for large-scale gene expression analyses of laser capture microdissected bladder tissue

PURPOSE

Lower urinary tract symptoms (LUTS) can be caused by structural and functional changes in different compartments of the bladder. To enable extensive investigations of individual regions even in small bladder biopsies, we established a combination protocol consisting of three molecular techniques: laser capture microdissection microscopy (LCM), RNA preamplification and quantitative polymerase chain reaction (qPCR).

METHODS

Urinary bladders of ten mice were resected and frozen immediately or after a delay of 15 min. Cryosections were obtained and smooth muscle was isolated using the LCM technique. Then, RNA was extracted, including protocols with and without DNase digestion as well as with and without the addition of carrier RNA. Extracted RNA was either used for reverse transcriptase (RT)-PCR plus qPCR or for a combination of RNA preamplification and qPCR.

RESULTS

Our data showed that with RNA preamplification, 10 μg cDNA can be regularly generated from 2.5 ng RNA. Depending on expression levels, this is sufficient for hundreds of pPCR reactions. The efficiency of preamplification, however, was gene-dependent. DNase digestion before preamplification lead to lower threshold cycles in qPCR. The use of partly degraded RNA for RNA preamplification did not change the results of the following qPCR.

CONCLUSIONS

RNA preamplification strongly enlarges the spectrum of genes to be analyzed in distinct bladder compartments by qPCR. It is an easy and reliable method that can be realized with standard laboratory equipment. Our protocol may lead in near future to a better understanding of the pathomechanisms in LUTS.

Measurement of blood flow in arteriovenous malformations before and after embolization using arterial spin labeling

The assessment of shunt reduction after an embolization of an arteriovenous malformation (AVM) or fistula (AVF) from conventional angiography is often difficult and may be subjective. Here we present a completely non-invasive method using magnetic resonance imaging (MRI) to measure shunt reduction. Using pulsed arterial spin labeling (PASL), we determined the relative amount of signal attributed to the shunt over 1.75 s and 6 different slices covering the lesion. This amount of signal from the shunt was related to the total signal from all slices and measured before and after embolization. The method showed a fair agreement between the PASL results and the judgement from conventional angiography. In the case of a total or subtotal shunt occlusion, PASL showed a shunt reduction between 69% and 92%, whereas in minimal shunt reduction as judged by conventional angiography, the ASL result was -6% (indicating slightly increased flow) to 35% in a partially occluded vein of Galen aneurysm. The PASL method proved to be fairly reproducible (up to 2% deviation between three measurements without interventions). On conclusion, PASL is able to reliably measure the amount of shunt reduction achieved by embolization of AVMs and AVFs.

Involvement of globus pallidus and midbrain nuclei in pantothenate kinase-associated neurodegeneration: measurement of T2 and T2* time

PURPOSE

To quantify involvement of globus pallidus and two midbrain nuclei (substantia nigra and red nucleus) in Pantothenate Kinase-Associated Neurodegeneration (PKAN).

MATERIAL AND METHODS

We performed T2 and T2* weighted imaging with calculation of the corresponding relaxation times on a subset of 5 patients from a larger group of 20 patients with PKAN from the southwest part of the Dominican Republic. Examinations were carried out on a 3T scanner and included a multi-echo spin-echo as well as a multi-echo gradient echo sequence. Results were compared to a control group of 19 volunteers.

RESULTS

T2 and T2* weighted sequences showed abnormal signal reduction in the globus pallidus of all patients. On T2* weighted imaging, abnormal signal in the substantia nigra could reliably be detected in 75% of cases, but differentiation from normal was less reliable in T2 weighted scans. Correspondingly, relaxation times differed from normal with very high significance (p < 0.0001) in the globus pallidus, but with with less significance in the substantia nigra (p ≤ 0.03). The red nucleus was not affected.

CONCLUSIONS

Signal reduction in the globus pallidus, which probably is due to abnormal accumulation of iron, is severe in PKAN and can be differentiated from normal with high reliability. The substantia nigra is affected to a lesser degree, and the red nucleus is not involved. The reason for this selective susceptibility of normally iron-rich brain structures for pathological accumulation of iron remains speculative. Our quantitative results might be helpful to assess the value of an iron chelation approach to therapy.