A genetic basis for sex differences in Xp11 translocation renal cell carcinoma.

Xp11 translocation renal cell carcinoma (tRCC) is a rare, female-predominant cancer driven by a fusion between the transcription factor binding to IGHM enhancer 3 (TFE3) gene on chromosome Xp11.2 and a partner gene on either chromosome X (chrX) or an autosome. It remains unknown what types of rearrangements underlie TFE3 fusions, whether fusions can arise from both the active (chrXa) and inactive X (chrXi) chromosomes, and whether TFE3 fusions from chrXi translocations account for the female predominance of tRCC. To address these questions, we performed haplotype-specific analyses of chrX rearrangements in tRCC whole genomes. We show that TFE3 fusions universally arise as reciprocal translocations and that oncogenic TFE3 fusions can arise from chrXi:autosomal translocations. Female-specific chrXi:autosomal translocations result in a 2:1 female-to-male ratio of TFE3 fusions involving autosomal partner genes and account for the female predominance of tRCC. Our results highlight how X chromosome genetics constrains somatic chrX alterations and underlies cancer sex differences.

Classification of subtask types and skill levels in robot-assisted surgery using EEG, eye-tracking, and machine learning.

BACKGROUND: Objective and standardized evaluation of surgical skills in robot-assisted surgery (RAS) holds critical importance for both surgical education and patient safety. This study introduces machine learning (ML) techniques using features derived from electroencephalogram (EEG) and eye-tracking data to identify surgical subtasks and classify skill levels. METHOD: The efficacy of this approach was assessed using a comprehensive dataset encompassing nine distinct classes, each representing a unique combination of three surgical subtasks executed by surgeons while performing operations on pigs. Four ML models, logistic regression, random forest, gradient boosting, and extreme gradient boosting (XGB) were used for multi-class classification. To develop the models, 20% of data samples were randomly allocated to a test set, with the remaining 80% used for training and validation. Hyperparameters were optimized through grid search, using fivefold stratified cross-validation repeated five times. Model reliability was ensured by performing train-test split over 30 iterations, with average measurements reported. RESULTS: The findings revealed that the proposed approach outperformed existing methods for classifying RAS subtasks and skills; the XGB and random forest models yielded high accuracy rates (88.49% and 88.56%, respectively) that were not significantly different (two-sample t-test; P-value = 0.9). CONCLUSION: These results underscore the potential of ML models to augment the objectivity and precision of RAS subtask and skill evaluation. Future research should consider exploring ways to optimize these models, particularly focusing on the classes identified as challenging in this study. Ultimately, this study marks a significant step towards a more refined, objective, and standardized approach to RAS training and competency assessment.

Differential effects of obesity on perioperative outcomes in renal cell carcinoma patients based on race and ethnicity and neighborhood-level socioeconomic status.

Background: Obesity is a well-established risk factor of renal cell carcinoma (RCC), however the impact of obesity on surgical outcomes for racial and ethnic minority patients with RCC is unclear. This study investigated whether a higher body mass index (BMI) or obesity (BMI ≥30 kg/m2) was associated with worse perioperative outcomes and if there were heterogeneous effects based on race, ethnicity, and neighborhood-level socioeconomic factor. Methods: In this single-center cross-sectional study, medical records of patients who underwent partial or radical nephrectomy between 2010 and 2022 were retrospectively reviewed. Logistic regression analysis was performed to assess associations of BMI and perioperative outcomes [ischemia time, estimated blood loss (EBL), and length of hospital stay]. Results: A total of 432 patients, including 49.8% non-Hispanic White (NHW), 35.0% Hispanic, and 6.9% American Indian (AI) patients, were included. Median [interquartile range (IQR)] BMI was 30.2 (26.3-35.2) kg/m2, and Hispanic (31.5) and AI (32.5) patients had higher median BMI than NHW (29.1) patients (P=0.006). Median ischemia time, EBL, and length of hospital stay were 18.5 (IQR, 15.0-22.4) minutes, 150 (IQR, 75.0-300.0) mL, and 3 (IQR, 2-5) days. BMI ≥35 kg/m2 was associated with a longer ischemia time [>18.5 minutes; odds ratio (OR), 5.17; 95% confidence interval (CI): 1.81-14.76; P=0.002], and the association was stronger in NHW than Hispanic patients (BMI continuous OR, 1.13; 95% CI: 1.04-1.22; P=0.004 in NHW and OR, 1.07; 95% CI: 0.98-1.17; P=0.12 in Hispanics). Class I and II/III obese patients had over two-fold increased odds of a larger EBL (>150 mL) than patients with normal weight (OR, 2.17; 95% CI: 1.03-4.59; P=0.04 for class I and OR, 2.24; 95% CI: 1.04-4.84; P=0.04 for class II/III obese patients). This association was stronger in patients from neighborhoods with high social deprivation index (SDI) and in NHW patients (BMI ≥30 vs. <30 kg/m2, OR, 3.53; 95% CI: 1.57-7.97; P=0.002 in high SDI neighborhoods and OR, 2.38; 95% CI: 1.10-5.14; P=0.03 in NHW). BMI was not associated with a longer hospital stay. Conclusions: In this study, obesity increased likelihood of worse perioperative outcomes, and the associations varied based on race and ethnicity and neighborhood-level socioeconomic factors.

Stratification of Patients with Renal Cell Carcinoma by the Abundance of Sarcomatoid Features Reveals Differences in Survival and the Underlying Pathobiology.

Sarcomatoid renal cell carcinoma (sRCC) is histologically heterogeneous, with variable sarcomatoid amounts intermixed within epithelial carcinoma. However, the current classification for this aggressive disease is homogeneous and agnostic to the sarcomatoid proportion. We investigated whether sRCC subclassification has prognostic value and can reveal the biology underlying dedifferentiation and its clinical aggressiveness. On the basis of the intratumoral abundance of sarcomatoid features, cases were classified as sarcomatoid-high (≥10% sarcomatoid features) or sarcomatoid-low (<10% sarcomatoid features) in a cohort of 104 consecutive patients with sRCC undergoing nephrectomy at a single center. In comparison to sarcomatoid-low patients (n = 52), sarcomatoid-high patients (n = 52) had significantly shorter overall survival (median 14.5 vs 62.9 mo; p < 0.001), which was confirmed on multivariable analysis, and significantly shorter median metastasis-free survival among patients with clinically localized disease (10.7 vs 39.0 mo; p = 0.043). Transcriptomic analyses of 45 sRCC tumors revealed significant upregulation of nine hallmark pathways related to cell cycle/proliferation, epithelial-to-mesenchymal transition, reactive oxidative species, and interferon-α signaling among sarcomatoid-high (n = 24) versus sarcomatoid-low (n = 21) tumors. Categorization into transcriptomic clusters revealed predominance of proliferative, inflammatory, and immune effector phenotypes among sarcomatoid-high tumors, versus a hypoxia/angiogenesis phenotype among sarcomatoid-low tumors. Overall, these findings indicate prognostic value for sRCC subclassification into high versus low sarcomatoid groups and highlight key biology underlying the differences in clinical outcomes. PATIENT SUMMARY: Sarcomatoid renal cell carcinoma (sRCC) is a highly aggressive form of kidney cancer. The percentage of sarcomatoid features varies among tumors, but sRCC is still defined as a single kidney cancer type. Our results show that grouping patients according to their percentage of sarcomatoid features improves prediction of whether their tumors will become metastatic or lethal, and reveal molecular differences that may be important for this disease. Future assignment of sRCC to high and low sarcomatoid groups may help in guiding research and patient management.

A genetic basis for cancer sex differences revealed in Xp11 translocation renal cell carcinoma.

Xp11 translocation renal cell carcinoma (tRCC) is a female-predominant kidney cancer driven by translocations between the TFE3 gene on chromosome Xp11.2 and partner genes located on either chrX or on autosomes. The rearrangement processes that underlie TFE3 fusions, and whether they are linked to the female sex bias of this cancer, are largely unexplored. Moreover, whether oncogenic TFE3 fusions arise from both the active and inactive X chromosomes in females remains unknown. Here we address these questions by haplotype-specific analyses of whole-genome sequences of 29 tRCC samples from 15 patients and by re-analysis of 145 published tRCC whole-exome sequences. We show that TFE3 fusions universally arise as reciprocal translocations with minimal DNA loss or insertion at paired break ends. Strikingly, we observe a near exact 2:1 female:male ratio in TFE3 fusions arising via X:autosomal translocation (but not via X inversion), which accounts for the female predominance of tRCC. This 2:1 ratio is at least partially attributable to oncogenic fusions involving the inactive X chromosome and is accompanied by partial re-activation of silenced chrX genes on the rearranged chromosome. Our results highlight how somatic alterations involving the X chromosome place unique constraints on tumor initiation and exemplify how genetic rearrangements of the sex chromosomes can underlie cancer sex differences.

Impact of an NCCN-Compliant Multidisciplinary Conference on Treatment Decisions for Localized Prostate Cancer.

BACKGROUND: We sought to investigate the impact of an NCCN-compliant multidisciplinary conference on treatment decisions of patients with localized prostate cancer. METHODS: A retrospective review of our quality assurance localized prostate cancer database was performed. All patients with localized prostate cancer who sought a second opinion at Roswell Park Comprehensive Cancer Center between 2009 and 2019 were presented to the multidisciplinary Localized Prostate Cancer Conference (LPCC) that includes urologists, radiation oncologists, pathologists, and patient advocates. Multivariable regression models were fit to evaluate variables associated with concordance between community recommendations, LPCC recommendations, and treatment received by patients. RESULTS: A total of 1,164 patients were identified, of whom 26% had NCCN very low-/low-risk, 27% had favorable intermediate-risk, 25% had unfavorable intermediate-risk, and 22% had high-/very high-risk prostate cancer. Pathology changed in 11% of patients after genitourinary pathologist review, which caused disease reclassification in 9%. Concordance between community and LPCC recommendations occurred in 78%, with lowest concordance for androgen deprivation therapy (21%) and radiotherapy (53%). Concordance between community recommendations and treatment received occurred in 65%, with lowest concordance for androgen deprivation therapy and radiotherapy; among those who were recommended radiotherapy as the only option by their community urologist, only 26% received it. Concordance between LPCC recommendations and treatment received occurred in 92%. CONCLUSIONS: Community recommendations differed from the multidisciplinary NCCN-compliant recommendations in 22% of patients, primarily for radiotherapy. Multidisciplinary recommendations matched the treatment received in 92% of patients compared with 65% for community recommendations.

Stability of renal parenchymal volume and function during active surveillance of renal oncocytoma patients.

INTRODUCTION AND OBJECTIVE: To evaluate whether significant loss in ipsilateral renal parenchymal volume (IRPV) and renal function occurs during active surveillance (AS) of renal oncocytoma (RO) patients. METHODS: Renal function (estimated glomerular filtration rate, eGFR) dynamics were retrospectively analyzed in 32 consecutive biopsy-diagnosed RO patients managed with AS at a National Comprehensive Cancer Network institute. Three-dimensional kidney and tumor reconstructions were generated and IRPV was calculated using volumetry software (Myrian®) for all patients with manually estimated RO growth >+10 cm3. GFR and IRPV were compared at AS initiation vs. the last follow-up using 2-sided paired t-tests. The correlation between change in IRPV and change in RO size or GFR was tested using a Spearman coefficient. RESULTS: With median follow-up of 37 months, there was no significant change between initial vs. last eGFR (median 71.0 vs. 70.5 ml/min/1.73 m2, P = 0.50; median change -3.0 ml/min/1.73 m2). Among patients (n = 17) with RO growth >+10 cm3 during AS (median growth +28.6 cm3, IQR +16.9- + 46.5 cm3), IRPV generally remained stable (median change +0.5%, IQR -1.2%- + 1.2%), with only 2 cases surpassing 5% loss. No IRPV loss was detected among any patient within the top tertile of RO growth magnitude. RO growth magnitude did not correlate with loss of either IRPV (ρ = -0.30, P = 0.24) or eGFR (ρ = -0.16, P = 0.40), including among patient subsets with lower initial eGFR. Study limitations include a lack of long-term follow-up. CONCLUSIONS: Volumetry is a promising novel tool to measure kidney and tumor tissue changes during AS. Our study using volumetry indicates that clinically significant loss of IRPV or eGFR is uncommon and unrelated to tumor growth among untreated RO patients with intermediate follow-up. These findings support that AS is in general functionally safe for RO patients, however longer study is needed to determine safety durability, particularly among uncommon ≥cT2 RO variants.

Postoperative Restrictive Opioid Protocols and Durable Changes in Opioid Prescribing and Chronic Opioid Use.

Importance: Changes in postsurgical opioid prescribing practices may help reduce chronic opioid use in surgical patients. Objective: To investigate whether postsurgical acute pain across different surgical subspecialties can be managed effectively after hospital discharge with an opioid supply of 3 or fewer days and whether this reduction in prescribed opioids is associated with reduced new, persistent opioid use. Design, Setting, and Participants: In this prospective cohort study with a case-control design, a restrictive opioid prescription protocol (ROPP) specifying an opioid supply of 3 or fewer days after discharge from surgery along with standardized patient education was implemented across all surgical services at a tertiary-care comprehensive cancer center. Participants were all patients who underwent surgery from August 1, 2018, to July 31, 2019. Main Outcomes and Measures: Main outcomes were the rate of compliance with the ROPP in each surgical service, the mean number of prescription days and refill requests, type of opioid prescribed, and rate of conversion to chronic opioid use determined via a state-run opioid prescription program. Postsurgical complications were also measured. Results: A total of 4068 patients (mean [SD] age, 61.0 [13.8] years; 2528 women [62.1%]) were included, with 2017 in the pre-ROPP group (August 1, 2018, to January 31, 2019) and 2051 in the post-ROPP group (February 1, 2019, to July 31, 2019). The rate of compliance with the protocol was 95%. After implementation of the ROPP, mean opioid prescription days decreased from a mean (SD) of 3.9 (4.5) days in the pre-ROPP group to 1.9 (3.6) days in the post-ROPP group (P < .001). The ROPP implementation led to a 45% decrease in prescribed opioids after surgery (mean [SD], 157.22 [338.06] mean morphine milligram equivalents [MME] before ROPP vs 83.54 [395.70] MME after ROPP; P < .001). Patients in the post-ROPP cohort requested fewer refills (367 of 2051 [17.9%] vs 422 of 2017 [20.9%] in the pre-ROPP cohort; P = .02). There was no statistically significant difference in surgical complications. The conversion rate to chronic opioid use decreased following ROPP implementation among both opioid-naive patients with cancer (11.3% [143 of 1267] to 4.5% [118 of 2645]; P < .001) and those without cancer (6.1% [19 of 310] to 2.7% [16 of 600]; P = .02). Conclusions and Relevance: In this cohort study, prescribing an opioid supply of 3 or fewer days to surgical patients after hospital discharge was feasible for most patients, led to a significant decrease in the number of opioids prescribed after surgery, and was associated with a significantly decreased conversion to long-term opioid use without concomitant increases in refill requests or significant compromises in surgical recovery.

Iron accumulation typifies renal cell carcinoma tumorigenesis but abates with pathological progression, sarcomatoid dedifferentiation, and metastasis.

Iron is a potent catalyst of oxidative stress and cellular proliferation implicated in renal cell carcinoma (RCC) tumorigenesis, yet it also drives ferroptosis that suppresses cancer progression and represents a novel therapeutic target for advanced RCC. The von Hippel Lindau (VHL)/hypoxia-inducible factor-α (HIF-α) axis is a major regulator of cellular iron, and its inactivation underlying most clear cell (cc) RCC tumors introduces both iron dependency and ferroptosis susceptibility. Despite the central role for iron in VHL/HIF-α signaling and ferroptosis, RCC iron levels and their dynamics during RCC initiation/progression are poorly defined. Here, we conducted a large-scale investigation into the incidence and prognostic significance of total tissue iron in ccRCC and non-ccRCC patient primary tumor cancer cells, tumor microenvironment (TME), metastases and non-neoplastic kidneys. Prussian Blue staining was performed to detect non-heme iron accumulation in over 1600 needle-core sections across multiple tissue microarrays. We found that RCC had significantly higher iron staining scores compared with other solid cancers and, on average, >40 times higher than adjacent renal epithelium. RCC cell iron levels correlated positively with TME iron levels and inversely with RCC levels of the main iron uptake protein, transferrin receptor 1 (TfR1/TFRC/CD71). Intriguingly, RCC iron levels, including in the TME, decreased significantly with pathologic (size/stage/grade) progression, sarcomatoid dedifferentiation, and metastasis, particularly among patients with ccRCC, despite increasing TfR1 levels, consistent with an increasingly iron-deficient tumor state. Opposite to tumor iron changes, adjacent renal epithelial iron increased significantly with RCC/ccRCC progression, sarcomatoid dedifferentiation, and metastasis. Lower tumor iron and higher renal epithelial iron each predicted significantly shorter ccRCC patient metastasis-free survival. In conclusion, iron accumulation typifies RCC tumors but declines toward a relative iron-deficient tumor state during progression to metastasis, despite precisely opposite dynamics in adjacent renal epithelium. These findings raise questions regarding the historically presumed selective advantage for high iron during all phases of cancer evolution, suggesting instead distinct tissue-specific roles during RCC carcinogenesis and early tumorigenesis versus later progression. Future study is warranted to determine how the relative iron deficiency of advanced RCC contributes to ferroptosis resistance and/or introduces a heightened susceptibility to iron deprivation that might be therapeutically exploitable.

2022 WUOF/SIU International Consultation on Urological Diseases: Active Surveillance for Small Renal Masses.

With greater awareness of indolence underlying small renal masses (SRM ≤ 4 cm) and the morbidity of invasive treatment, active surveillance for SRM patients is being increasingly utilized on an international level. This synopsis summarizes the 2022 review and expert opinion recommendations provided to the International Consultation of Urological Diseases (ICUD) by 10 urologists from high-volume active surveillance practices at international centers. Topics reviewed include SRM biology and clinical behavior, current national and international guidelines for active surveillance of SRM patients, active surveillance utilization patterns and barriers to implementation, outcomes and limitations of the active surveillance literature, criteria for active surveillance patient selection, protocols for active surveillance management including frequency/modality of imaging and the role of renal tumor biopsy, triggers for delayed intervention during active surveillance including tumor factors and patient factors, and pathological outcomes of delayed intervention. We conclude that despite limitations of the current literature, active surveillance is a safe initial management strategy for many SRM patients. The slow growth and low metastatic potential of SRMs, combined with no evidence to suggest oncologic compromise with delay to treatment, should provide confidence to both patients and providers who are considering active surveillance. Future research for prioritization should include characterization of long-term active surveillance outcomes including rates of metastasis and delayed intervention, standardization of objective tumor progression criteria for triggering delayed intervention, and further delineation of the role for active surveillance in young and healthy patients.

Active Surveillance for Risk Stratification of All Small Renal Masses Lacking Predefined Clinical Criteria for Intervention.

PURPOSE: Despite general indolence of small renal masses and no known adversity from treatment delays, broad usage of active surveillance as a means to risk-stratify patients with small renal masses for more selective treatment has not been studied. We describe outcomes for a novel approach in which active surveillance was recommended to all patients with small renal masses lacking predefined progression criteria for intervention. MATERIALS AND METHODS: All nondialysis dependent patients with nonmetastatic small renal masses seen by 1 urologist at a comprehensive cancer center during January 2013-September 2017 were managed with active surveillance if standardized progression criteria for intervention were absent, with delayed intervention recommended only upon progression criteria for intervention development. Progression criteria for intervention were defined prospectively as small renal mass-related symptoms, unfavorable histology, cT3a stage or either of the following without benign neoplastic biopsy histology: longest tumor diameter >4 cm; growth rate >5 mm/year for longest tumor diameter ≤3 cm or >3 mm/year for longest tumor diameter >3 cm. RESULTS: In all, 96% (123/128) of patients with small renal masses lacked progression criteria for intervention at presentation and underwent active surveillance. With median/mean 31/34 months followup, none developed metastasis and 30% (37/123) developed progression criteria for intervention, 78% (29/37) of whom underwent delayed intervention. One (1%) patient crossed over to delayed intervention without progression criteria for intervention. Three-year progression criteria for intervention-free and delayed intervention-free rates were 72% and 75%, respectively. Delayed intervention resections were enriched (62%) for pT3 and/or nuclear grade 3-4 malignant pathology, with no benign resections. CONCLUSIONS: Active surveillance using predefined progression criteria for intervention in otherwise unselected patients with small renal masses allows intervention to be focused on at-risk small renal masses with common adverse pathology, avoiding treatment for most patients with small renal masses. Long-term delayed intervention and oncologic safety require study.

Feasibility and continence outcomes of extended prostatic urethral preservation during robot-assisted radical prostatectomy.

BACKGROUND: The prostatic urethra is conventionally resected during robot-assisted radical prostatectomy (RARP). We describe the technical feasibility and urinary continence outcomes of extended prostatic urethral preservation (EPUP) during RARP. METHODS: A single surgeon at a National Comprehensive Cancer Network institute performed 48 consecutive RARP operations using EPUP from March 2014 to March 2016, during which time 177 conventional non-EPUP RARP operations were performed by other surgeons. Prior to this period, the EPUP surgeon had performed 17 non-EPUP RARP operations over 15 months. Total intracorporeal urethral length (IUL) preserved during EPUP was measured intraoperatively. Associations of EPUP and IUL with continence recovery rates and/or times were tested in Fisher's exact and log rank univariate analyses and Cox logistic regression multivariable analyses. RESULTS: Median IUL preserved during EPUP was 4.0 cm (range 2.5-6.0 cm), and urethral dissections typically spanned the prostatic apex to mid-gland or base. Seven-week continence rates were significantly higher with versus without EPUP. EPUP patient rates of using 0 or 0-1 pads per day immediately after catheter removal were 19% and 35%, respectively. These rates increased significantly (53% and 76%, respectively), as did the IUL preserved (median 5.0 cm), among more recent EPUP patients (n = 17), which suggested a learning curve. In multivariable analyses including all patients, an EPUP approach was an independent predictor of faster continence recovery. In multivariable analyses of the EPUP subset, a longer IUL preserved was independently associated with faster continence recovery. No EPUP patient had a urethral fossa positive margin, and apical positive margins were similarly infrequent among EPUP and non-EPUP patients. CONCLUSIONS: EPUP is technically feasible during RARP and associated with faster continence recovery. Future investigation into the generalizability of these findings and the oncologic safety of EPUP is warranted.

Preclinical efficacy of dual mTORC1/2 inhibitor AZD8055 in renal cell carcinoma harboring a TFE3 gene fusion.

BACKGROUND: Renal cell carcinomas (RCC) harboring a TFE3 gene fusion (TfRCC) represent an aggressive subset of kidney tumors. Key signaling pathways of TfRCC are unknown and preclinical in vivo data are lacking. We investigated Akt/mTOR pathway activation and the preclinical efficacy of dual mTORC1/2 versus selective mTORC1 inhibition in TfRCC. METHODS: Levels of phosphorylated Akt/mTOR pathway proteins were compared by immunoblot in TfRCC and clear cell RCC (ccRCC) cell lines. Effects of the mTORC1 inhibitor, sirolimus, and the dual mTORC1/2 inhibitor, AZD8055, on Akt/mTOR activation, cell cycle progression, cell viability and cytotoxicity were compared in TfRCC cells. TfRCC xenograft tumor growth in mice was evaluated after 3-week treatment with oral AZD8055, intraperitoneal sirolimus and respective vehicle controls. RESULTS: The Akt/mTOR pathway was activated to a similar or greater degree in TfRCC than ccRCC cell lines and persisted partly during growth factor starvation, suggesting constitutive activation. Dual mTORC1/2 inhibition with AZD8055 potently inhibited TfRCC viability (IC50 = 20-50 nM) due at least in part to cell cycle arrest, while benign renal epithelial cells were relatively resistant (IC50 = 400 nM). Maximal viability reduction was greater with AZD8055 than sirolimus (80-90% versus 30-50%), as was the extent of Akt/mTOR pathway inhibition, based on significantly greater suppression of P-Akt (Ser473), P-4EBP1, P-mTOR and HIF1α. In mouse xenograft models, AZD8055 achieved significantly better tumor growth inhibition and prolonged mouse survival compared to sirolimus or vehicle controls. CONCLUSIONS: Akt/mTOR activation is common in TfRCC and a promising therapeutic target. Dual mTORC1/2 inhibition suppresses Akt/mTOR signaling more effectively than selective mTORC1 inhibition and demonstrates in vivo preclinical efficacy against TFE3-fusion renal cell carcinoma.

Suppressive effects of iron chelation in clear cell renal cell carcinoma and their dependency on VHL inactivation.

Increasing data implicate iron accumulation in tumorigenesis of the kidney, particularly the clear cell renal cell carcinoma (ccRCC) subtype. The von Hippel Lindau (VHL)/hypoxia inducible factor-α (HIF-α) axis is uniquely dysregulated in ccRCC and is a major regulator and regulatory target of iron metabolism, yet the role of iron in ccRCC tumorigenesis and its potential interplay with VHL inactivation remains unclear. We investigated whether ccRCC iron accumulation occurs due to increased cell dependency on iron for growth and survival as a result of VHL inactivation. Free iron levels were compared between four VHL-mutant ccRCC cell lines (786-0, A704, 769-P, RCC4) and two benign renal tubule epithelial cell lines (RPTEC, HRCEp) using the Phen Green SK fluorescent iron stain. Intracellular iron deprivation was achieved using two clinical iron chelator drugs, deferasirox (DFX) and deferoxamine (DFO), and chelator effects were measured on cell line growth, cell cycle phase, apoptosis, HIF-1α and HIF-2α protein levels and HIF-α transcriptional activity based on expression of target genes CA9, OCT4/POU5F1 and PDGFß/PDGFB. Similar assays were performed in VHL-mutant ccRCC cells with and without ectopic wild-type VHL expression. Baseline free iron levels were significantly higher in ccRCC cell lines than benign renal cell lines. DFX depleted cellular free iron more rapidly than DFO and led to greater growth suppression of ccRCC cell lines (>90% at ~30-150 µM) than benign renal cell lines (~10-50% at up to 250 µM). Similar growth responses were observed using DFO, with the exception that a prolonged treatment duration was necessary to deplete cellular iron adequately for differential growth suppression of the less susceptible A704 ccRCC cell line relative to benign renal cell lines. Apoptosis and G1-phase cell cycle arrest were identified as potential mechanisms of chelator growth suppression based on their induction in ccRCC cell lines but not benign renal cell lines. Iron chelation in ccRCC cells but not benign renal cells suppressed HIF-1α and HIF-2α protein levels and transcriptional activity, and the degree and timing of HIF-2α suppression correlated with the onset of apoptosis. Restoration of wild-type VHL function in ccRCC cells was sufficient to prevent chelator-induced apoptosis and G1 cell cycle arrest, indicating that ccRCC susceptibility to iron deprivation is VHL inactivation-dependent. In conclusion, ccRCC cells are characterized by high free iron levels and a cancer-specific dependency on iron for HIF-α overexpression, cell cycle progression and apoptotic escape. This iron dependency is introduced by VHL inactivation, revealing a novel interplay between VHL/HIF-α dysregulation and ccRCC iron metabolism. Future study is warranted to determine if iron deprivation using chelator drugs provides an effective therapeutic strategy for targeting HIF-2α and suppressing tumor progression in ccRCC patients.

Identification and Validation of Radiographic Enhancement for Reliable Differentiation of CD117(+) Benign Renal Oncocytoma and Chromophobe Renal Cell Carcinoma.

Purpose: The diagnostic differential for CD117/KIT(+) oncocytic renal tumor biopsies is limited to benign renal oncocytoma versus chromophobe renal cell carcinoma (ChRCC); however, further differentiation is often challenging and requires surgical resection. We investigated clinical variables that might improve preoperative differentiation of CD117(+) renal oncocytoma versus ChRCC to avoid the need for benign tumor resection.Experimental Design: A total of 124 nephrectomy patients from a single institute with 133 renal oncocytoma or ChRCC tumors were studied. Patients from 2003 to 2012 comprised a retrospective cohort to identify clinical/radiographic variables associated with renal oncocytoma versus ChRCC. Prospective validation was performed among consecutive renal oncocytoma/ChRCC tumors resected from 2013 to 2017.Results: Tumor size and younger age were associated with ChRCC, and multifocality with renal oncocytoma; however, the most reliable variable for ChRCC versus renal oncocytoma differentiation was the tumor:cortex peak early-phase enhancement ratio (PEER) using multiphase CT. Among 54 PEER-evaluable tumors in the retrospective cohort [19 CD117(+), 13 CD117(-), 22 CD117-untested], PEER classified each correctly as renal oncocytoma (PEER >0.50) or ChRCC (PEER ≤0.50), except for four misclassified CD117(-) ChRCC variants. Prospective study of PEER confirmed 100% accuracy of renal oncocytoma/ChRCC classification among 22/22 additional CD117(+) tumors. Prospective interobserver reproducibility was excellent for PEER scoring (intraclass correlation coefficient, ICC = 0.97) and perfect for renal oncocytoma/ChRCC assignment (ICC = 1.0).Conclusions: In the largest clinical comparison of renal oncocytoma versus ChRCC to our knowledge, we identified and prospectively validated a reproducible radiographic measure that differentiates CD117(+) renal oncocytoma from ChRCC with potentially 100% accuracy. PEER may allow reliable biopsy-based diagnosis of CD117(+) renal oncocytoma, avoiding the need for diagnostic nephrectomy. Clin Cancer Res; 24(16); 3898-907. ©2018 AACR.

Development of a Patient-Based Model for Estimating Operative Times for Robot-Assisted Radical Prostatectomy.

OBJECTIVES: To develop a methodology for predicting operative times for robot-assisted radical prostatectomy (RARP) using preoperative patient, disease, procedural, and surgeon variables to facilitate operating room (OR) scheduling. METHODS: The model included preoperative metrics: body mass index (BMI), American Society of Anesthesiologists score, clinical stage, National Comprehensive Cancer Network risk, prostate weight, nerve-sparing status, extent and laterality of lymph node dissection, and operating surgeon (six surgeons were included in the study). A binary decision tree was fit using a conditional inference tree method to predict operative times. The variables most associated with operative time were determined using permutation tests. Data were split at the value of the variable that results in the largest difference in mean for surgical time across the split. This process was repeated recursively on the resultant data. RESULTS: A total of 1709 RARPs were included. The variable most strongly associated with operative time was the surgeon (surgeons 2 and 4-102 minutes shorter than surgeons 1, 3, 5, and 6, p < 0.001). Among surgeons 2 and 4, BMI had the strongest association with surgical time (p < 0.001). Among patients operated by surgeons 1, 3, 5, and 6, RARP time was again most strongly associated with the surgeon performing RARP. Surgeons 1, 3, and 6 were on average 76 minutes faster than surgeon 5 (p < 0.001). The regression tree output in the form of box plots showed operative time median and ranges according to patient, disease, procedural, and surgeon metrics. CONCLUSION: We developed a methodology that can predict operative times for RARP based on patient, disease and surgeon variables. This methodology can be utilized for quality control, facilitate OR scheduling, and maximize OR efficiency.

Blinded review of archival radical prostatectomy specimens supports that contemporary Gleason score 6 prostate cancer lacks metastatic potential.

BACKGROUND: Retrospective identification of Gleason pattern 4 in metastatic Gleason score 3 + 3 = 6 (GS6) radical prostatectomy (RP) specimens has suggested true GS6 prostate cancer (CaP) lacks metastatic potential. However, pathologist awareness of study design and metastasis outcomes at the time of RP review might have introduced upgrading bias. We used pathologist-blinded methodology for unbiased characterization of metastasis rates for contemporarily defined pathologic GS6 (pGS6) CaP. METHODS: An institutional RP database was queried to identify pGS6 patients with metastasis or concern for micrometastasis based on: 1) biochemical failure (BF) despite negative surgical margins or 2) incomplete biochemical response to salvage/adjuvant radiation. RP specimens were regraded independently by two genitourinary pathologists blinded to study aims or clinical outcomes. Additional blinding was performed by random inclusion of pGS6 control specimens from BF-free patients. Only upgrading identified independently by both pathologists was considered. RESULTS: Among 451 pGS6 patients identified, none had synchronous lymph node metastases and 43/451 (10%) suffered BF. Two patients (0.4%) developed metachronous metastasis during a 110-month median follow-up for BF patients. Both metastatic cases had Gleason pattern 4 on blinded RP review, as did 88% of cases with concern for micrometastasis versus 38% of control cases (P = 0.02). All BF patients (29/29) undergoing postoperative radiation had a complete biochemical response or Gleason pattern 4 on blinded RP review. CONCLUSIONS: Unbiased pathologist review of archival RP specimens supports absent metastatic potential for contemporarily defined GS6 CaP. Reduced postoperative monitoring is appropriate for pGS6, but may require pathology review to confirm absent Gleason pattern 4.

Transferrin receptor 1 upregulation in primary tumor and downregulation in benign kidney is associated with progression and mortality in renal cell carcinoma patients.

The central dysregulated pathway of clear cell (cc) renal cell carcinoma (RCC), the von Hippel Lindau/hypoxia inducible factor-α axis, is a key regulator of intracellular iron levels, however the role of iron uptake in human RCC tumorigenesis and progression remains unknown. We conducted a thorough, large-scale investigation of the expression and prognostic significance of the primary iron uptake protein, transferrin receptor 1 (TfR1/CD71/TFRC), in RCC patients. TfR1 immunohistochemistry was performed in over 1500 cores from 574 renal cell tumor patient tissues (primary tumors, matched benign kidneys, metastases) and non-neoplastic tissues from 36 different body sites. TfR1 levels in RCC tumors, particularly ccRCC, were significantly associated with adverse clinical prognostic features (anemia, lower body mass index, smoking), worse tumor pathology (size, stage, grade, multifocality, sarcomatoid dedifferentiation) and worse survival outcomes, including after adjustments for tumor pathology. Highest TfR1 tissue levels in the non-gravid body were detected in benign renal tubule epithelium. Opposite to TfR1 changes in the primary tumor, TfR1 levels in benign kidney dropped during tumor progression and were inversely associated with worse survival outcomes, independent of tumor pathology. Quantitative measurement of TfR1 subcellular localization in cell lines demonstrated mixed cytoplasmic and membranous expression with increased TfR1 in clusters in ccRCC versus benign renal cell lines. Results of this study support an important role for TfR1 in RCC progression and identify TfR1 as a novel RCC biomarker and therapeutic target.

Validation of the Kattan Nomogram for Prostate Cancer Recurrence After Radical Prostatectomy.

BACKGROUND: The Kattan postoperative radical prostatectomy (RP) nomogram is used to predict biochemical recurrence-free progression (BCRFP) after RP. However, external validation among contemporary patients using modern outcome definitions is limited. METHODS: A total of 1,931 patients who underwent RP at Roswell Park Cancer Institute (RPCI) between 1993 and 2014 (median follow-up, 47 months; range, 0-244 months) were assessed for NCCN-defined biochemical failure (BF) and RPCI-defined treatment failure (TF). Actual rates of biochemical failure-free survival (BFS; defined as 1 - BF) and treatment failure-free survival (TFS; defined as 1 - TF) were compared with Kattan BCRFP nomogram predictions. RESULTS: The Kattan BCRFP nomogram predictions at 5 and 10 years were predictive of BFS (area under the receiver operating characteristic curve [AUC], 0.772) and TFS (AUC, 0.774). The Kattan BCRFP nomogram tended to underestimate BFS and TFS compared with actual outcomes. The Kattan 5-year BCRFP predictions consistently overestimated actual 5-year BFS outcomes among subgroups of high- and intermediate-risk patients with at least 5-year outcomes. CONCLUSIONS: The Kattan BCRFP nomogram is a robust predictor of NCCN-defined BF in a large sample of patients with RP with substantial follow-up and modern, standardized failure definitions.

Implications of High Rates of Metastatic Prostate Cancer in BRCA2 Mutation Carriers.

BACKGROUND: Patients with germline BRCA2 gene mutations (BRCA2mut) have more aggressive prostate cancer. Analysis of all reported germline BRCA2mut prostate cancer cases allows better understanding of the clinicopathologic features and survival outcomes of these men. METHODS: A systematic review was performed with the MEDLINE database to capture articles evaluating clinicopathologic characteristics of men with BRCA2mut associated prostate cancer. Inclusion criteria were at least five subjects, confirmation of BRCA2mut status, and data for at least 2 clinical parameters of disease. Meta-analysis was performed on outcomes data. Chi-squared tests were used to compare disease features among men undergoing formal versus ad hoc screening, as well as an age of diagnosis less than versus greater than 65 years. Rates of metastatic disease among BRCA2mut cases were compared to rates among non-carrier control subjects and the general population using the SEER database. RESULTS: Twelve out of 289 studies met our inclusion criteria, representing 261 BRCA2mut men. Among carriers, the median age at diagnosis was 62 years and median PSA was 15 ng/dl with 95% of men having a PSA>3. Over 40% of BRCA2mut patients had T3/T4 disease and over 25% were metastatic at presentation. Survival was worse in BRCA2mut men with prostate cancer when compared to non-BRCA2mut subjects. BRCA2mut carriers had significantly higher rates of metastatic disease (18%) versus non-carrier controls (8%) and the SEER population (4%). CONCLUSIONS: BRCA2mut carriers are more likely to have poor risk of prostate cancer at presentation and exhibit worse oncologic outcomes relative to non-carriers, including a fourfold increase in metastatic disease. Younger men and those undergoing formal screening present with less advanced disease which supports a need for earlier identification and screening protocols. Additionally, this population may benefit from alternative therapeutic paradigms. Prostate 76:1135-1145, 2016. © 2016 Wiley Periodicals, Inc.