The effect of a fermented soy beverage among patients with localized prostate cancer prior to radical prostatectomy

BACKGROUND

Fermented soy products have shown to possess inhibitory effects on prostate cancer (PCa). We evaluated the effect of a fermented soy beverage (Q-Can®), containing medium-chain triglycerides, ketones and soy isoflavones, among men with localized PCa prior to radical prostatectomy.

METHODS

We conducted a placebo-controlled, double-blind randomized trial of Q-Can®. Stratified randomization (Cancer of the Prostate Risk Assessment (CAPRA) score at diagnosis) was used to assign patients to receive Q-Can® or placebo for 2-5 weeks before RP. Primary endpoint was change in serum PSA from baseline to end-of-study. We assessed changes in other clinical and pathologic endpoints. The primary ITT analysis compared PSA at end-of-study between randomization arms using repeated measures linear mixed model incorporating baseline CAPRA risk strata.

RESULTS

We randomized 19 patients, 16 were eligible for analysis of the primary outcome. Mean age at enrollment was 61, 9(56.2%) were classified as low and intermediate risk, and 7(43.8%) high CAPRA risk. Among patients who received Q-Can®, mean PSA at baseline and end-of-study was 8.98(standard deviation, SD 4.07) and 8.02ng/mL(SD 3.99) compared with 8.66(SD 2.71) to 9.53ng/mL(SD 3.03), respectively, (Difference baseline - end-of-study, p = 0.36). There were no significant differences in Gleason score, clinical stage, surgical margin status, or CAPRA score between treatment arms (p > 0.05), and no significant differences between treatment arms in end-of-study or change in lipids, testosterone and FACT-P scores (p > 0.05).

CONCLUSIONS

Short exposure to Q-Can® among patients with localized PCa was not associated with changes in PSA levels, PCa characteristics including grade and stage or serum testosterone. Due to early termination from inability to recruit, study power, was not achieved.

Social determinants as predictors of resection and long-term mortality in Black patients with non-small cell lung cancer

BACKGROUND

Minorities diminished returns theory posits that socioeconomic attainment conveys fewer health benefits for Black than White individuals. The current study evaluates the effects of social constructs on resection rates and survival for non-small cell lung cancer (NSCLC).

METHODS

Patients with potentially resectable NSCLC stage IA to IIIA were identified using the 2004 to 2017 National Cancer Database. Patients were stratified into quartiles based on population-level education and income. Logistic regression was used to predict risk-adjusted resection rates. Mortality was assessed with Cox proportional hazard modeling.

RESULTS

Of the 416,025 patients identified, 213,643 (51.4%) underwent resection. Among White patients, the lowest income (adjusted odds ratio 0.76, 95% confidence interval 0.74-0.78, P < .01) and education quartiles (adjusted odds ratio 0.82, 95% confidence interval 0.79-0.84, P < .01) were associated with decreased odds of resection. The lowest education quartile among Black patients was not associated with lower resection rates. The lowest income quartile (adjusted odds ratio 0.67, 95% CI 0.61-0.74, P < .01) was associated with reduced resection. White patients in the lowest education and income quartiles experienced increased hazard of 5-year mortality (adjusted hazard ratio 1.13, 95% CI 1.11-1.15, P < .01 and adjusted hazard ratio 1.08, 95% CI 1.06-1.11, P < .01 respectively). In Black patients, there were no significant differences in 5-year survival between Black patients in the highest education and income quartiles and those in the lowest quartiles.

CONCLUSION

Among Black patients with NSCLC, educational attainment is not associated with increased resection rates. In addition, higher education and income were not associated with improved 5-year survival. The diminished gains experienced by Black patients, compared to Whites patients, illustrate the presence of pervasive race-specific mechanisms in observed inequalities in cancer outcomes.

Persistent racial disparities in refusal of resection in non-small cell lung cancer patients at high-volume and Black-serving institutions

BACKGROUND

Surgical resection is the standard of care for early-stage non-small cell lung cancer. Black patients have higher surgical refusal rates than White patients. We evaluated factors associated with the refusal of resection and subsequent non-small cell lung cancer outcomes.

METHODS

We identified patients with non-small cell lung cancer stages IA to IIIA eligible for surgical resection (lobectomy or pneumonectomy) listed between 2004 and 2017 in the National Cancer Database. We stratified hospitals by the proportion of Black patients served and lung cancer resection volume. We used multivariable regression models to identify factors associated with refusal of resection and assessed 5-year mortality using Kaplan-Meier analysis and Cox proportional hazard modeling.

RESULTS

Of 221,396 patients identified, 7,753 (3.5%) refused surgery. Black race was associated with increased refusal (adjusted odds ratio 2.06, 95% confidence interval 1.90-2.22). Compared to White race, Black race was associated with increased refusal across the highest (adjusted odds ratio 2.29, 95% confidence interval 1.94-2.54), intermediate (adjusted odds ratio 2.05, 95% confidence interval 1.78-2.37), and lowest (adjusted odds ratio 1.77, 95% confidence interval 1.58-1.99) volume tertiles. Similarly, Black race was associated with increased refusal across the highest (adjusted odds ratio 1.97, 95% confidence interval 1.78-2.17), intermediate (adjusted odds ratio 2.08, 95% confidence interval 1.80-2.40), and lowest (adjusted odds ratio 1.53, 95% confidence interval 1.13-2.06) Black-serving tertiles. However, surgical resection yielded similar 5-year survival for Black and White patients.

CONCLUSION

Racial disparities in non-small cell lung cancer surgery refusal persist regardless of hospital volume or proportion of Black patients served. These findings suggest that a better understanding of patient and patient-provider level interventions could facilitate a better understanding of treatment decision-making.

Adjuvant everolimus after surgery for renal cell carcinoma (EVEREST): a double-blind, placebo-controlled, randomised, phase 3 trial

BACKGROUND

Patients undergoing resection of renal cell carcinoma are at risk of disease relapse. We evaluated the effectiveness of the mammalian target of rapamycin inhibitor everolimus administered after surgery.

METHODS

In this randomised, double-blind, phase 3 trial, we enrolled adults with histologically confirmed renal cell carcinoma who had undergone a full surgical resection and were at intermediate-high or very high risk of recurrence at 398 academic and community institution centres in the USA. After nephrectomy, patients were randomly assigned (1:1) via a central web-based application using a dynamic balancing algorithm to receive 10 mg oral everolimus daily or placebo for 54 weeks. The primary endpoint was recurrence-free survival. Efficacy analyses included all eligible, randomly assigned patients; safety analysis included all patients who received treatment. This trial is registered with ClinicalTrials.gov, NCT01120249 and is closed to new participants.

FINDINGS

Between April 1, 2011, and Sept 15, 2016, a total of 1545 patients were randomly assigned to receive everolimus (n=775) or placebo (n=770), of whom 755 assigned to everolimus and 744 assigned to placebo were eligible for inclusion in the efficacy analysis. With a median follow-up of 76 months (IQR 61-92), recurrence-free survival was longer with everolimus than with placebo (5-year recurrence-free survival 67% [95% CI 63-70] vs 63% [60-67]; stratified log-rank p=0·050; stratified hazard ratio [HR] 0·85, 95% CI 0·72-1·00; p=0·051) but did not meet the prespecified p value for statistical significance of 0·044. Recurrence-free survival was longer with everolimus than with placebo in the very-high-risk group (HR 0·79, 95% CI 0·65-0·97; p=0·022) but not in the intermediate-high-risk group (0·99, 0·73-1·35; p=0·96). Grade 3 or higher adverse events occurred in 343 (46%) of 740 patients who received everolimus and 79 (11%) of 723 who received placebo.

INTERPRETATION

Postoperative everolimus did not improve recurrence-free survival compared with placebo among patients with renal cell carcinoma at high risk of recurrence after nephrectomy. These results do not support the adjuvant use of everolimus for renal cell carcinoma after surgery.

FUNDING

US National Institutes of Health, National Cancer Institute, National Clinical Trials Network, Novartis Pharmaceuticals Corporation, and The Hope Foundation.

Comparative analyses define differences between BHD-associated renal tumour and sporadic chromophobe renal cell carcinoma

BACKGROUND

Birt-Hogg-Dubé (BHD) syndrome, caused by germline alteration of folliculin (FLCN) gene, develops hybrid oncocytic/chromophobe tumour (HOCT) and chromophobe renal cell carcinoma (ChRCC), whereas sporadic ChRCC does not harbor FLCN alteration. To date, molecular characteristics of these similar histological types of tumours have been incompletely elucidated.

METHODS

To elucidate renal tumourigenesis of BHD-associated renal tumours and sporadic renal tumours, we conducted whole genome sequencing (WGS) and RNA-sequencing (RNA-seq) of sixteen BHD-associated renal tumours from nine unrelated BHD patients, twenty-one sporadic ChRCCs and seven sporadic oncocytomas. We then compared somatic mutation profiles with FLCN variants and RNA expression profiles between BHD-associated renal tumours and sporadic renal tumours.

FINDINGS

RNA-seq analysis revealed that BHD-associated renal tumours and sporadic renal tumours have totally different expression profiles. Sporadic ChRCCs were clustered into two distinct clusters characterized by L1CAM and FOXI1 expressions, molecular markers for renal tubule subclasses. Increased mitochondrial DNA (mtDNA) copy number with fewer variants was observed in BHD-associated renal tumours compared to sporadic ChRCCs. Cell-of-origin analysis using WGS data demonstrated that BHD-associated renal tumours and sporadic ChRCCs may arise from different cells of origin and second hit FLCN alterations may occur in early third decade of life in BHD patients.

INTERPRETATION

These data further our understanding of renal tumourigenesis of these two different types of renal tumours with similar histology.

FUNDING

This study was supported by JSPS KAKENHI Grants, RIKEN internal grant, and the Intramural Research Program of the National Institutes of Health (NIH), National Cancer Institute (NCI), Center for Cancer Research.

Disparate Utilization of Breast Conservation Therapy in the Surgical Management of Early-Stage Breast Cancer

BACKGROUND

Despite evidence suggesting oncologic equipoise of breast conservation therapy (BCT) for early-stage (stages I and II) breast cancer, mastectomy is still widely utilized.

PATIENTS AND METHODS

The 2004-2015 National Cancer Database was used to tabulate all adult women receiving mastectomy or BCT for early-stage breast cancer. Multivariable regression was used to evaluate factors associated with utilization of BCT, relative to mastectomy.

RESULTS

Of 1,079,057 women meeting study criteria, 57.4% underwent BCT. BCT patients were older and more commonly White, compared to mastectomy. They were more commonly privately insured, in the highest income quartile, and treated at metropolitan, nonacademic institutions. After adjustment, increasing age (AOR 1.01/year), Black race (AOR 1.21, Ref: White), and care at a community hospital (AOR 1.08, Ref: Academic; all P< .05) were associated with increased odds of undergoing BCT. Conversely, Asian or Pacific Islander (AAPI) race (AOR 0.74), Medicare (AOR 0.89) or Medicaid (AOR 0.95) coverage, and being in the lowest (AOR 0.95) and second lowest (AOR 0.98, all P< .05) income quartiles were associated with reduced odds of undergoing BCT. Finally, increasing tumor size (AOR 0.97, P< .05) was associated with decreased adjusted odds of undergoing BCT.

CONCLUSION

Our results suggest persistent socioeconomic and racial disparities in BCT utilization for early-stage breast cancer. Directed strategies should be implemented in order to reduce treatment inequality in this patient population.

Cost-effectiveness of minimally invasive partial nephrectomy and percutaneous cryoablation for cT1a renal cell carcinoma

BACKGROUND

There is growing evidence that partial nephrectomy (PN) and percutaneous cryoablation (PCA) yield comparable outcomes for patients with cT1a renal cell carcinoma (RCC), although the cost-effectiveness of both treatments still needs to be assessed.

PURPOSE

To perform a cost-effectiveness analysis of PN and PCA for patients with cT1a RCC.

MATERIALS AND METHODS

A decision analysis was created over a 5-year span from a healthcare payer's perspective computing expected costs and outcomes of PN and PCA in terms of quality-adjusted life-years (QALYs) and incremental cost-effectiveness (ICER). After each treatment, the following states were modelled using data from the recent literature: procedural complications, no evidence of disease (NED), local recurrence, metastases, and death from RCC- or non-RCC-related causes. Probabilistic and deterministic sensitivity analyses were performed.

RESULTS

PCA and PN yielded health benefits of 3.68 QALY and 3.67 QALY. Overall expected costs were $20,491 and $26,478 for PCA and PN. On probabilistic sensitivity analysis, PCA was more cost-effective than PN in 84.78% of Monte Carlo simulations. PCA was more cost-effective until its complication risk was at least 38% higher than PN. PCA was more cost-effective than PN when (i) PCAs annual local recurrence risk was < 3.5% higher than that of PN in absolute values; (ii) PCAs annual metastatic risk was < 1.0% higher than that of PN; or (iii) PCAs annual cancer-specific mortality risk < 0.65% higher than that of PN. PCA remained cost-effective until its procedural cost is above $13,875.

CONCLUSION

PCA appears to be more cost-effective than PN for the treatment of cT1a RCC, although the currently available evidence is of limited quality. PCA may be the better treatment strategy in the majority of scenarios varying procedural complications, recurrence, metastatic risk, and RCC-mortality in clinically plausible ranges.

KEY POINTS

• For patients with cT1a RCCs, PCA yields a comparable health benefit at lower costs compared to PN, making PCA the dominant and therefore more cost-effective treatment strategy over PN. • PCA was more cost-effective than PN when (i) PCAs annual local recurrence risk was < 3.5% higher than PN in absolute values; (ii) PCAs annual metastatic risk was < 1.0% higher than PN; or (iii) PCAs annual cancer-specific mortality risk < 0.65% higher than PN. • PCA is more cost-effective than PN for the treatment of cT1a RCC, and it remained so in the majority of scenarios varying procedural complications, recurrence, metastatic risk, and RCC mortality.

Results from phase 3 study of 89Zr-DFO-girentuximab for PET/CT imaging of clear cell renal cell carcinoma (ZIRCON)

LBA602

Background: The increasing detection of renal masses presents a significant patient management challenge. Diagnostic options include cross-sectional imaging, which cannot reliably differentiate benign and malignant renal masses, and biopsy, which is invasive and subject to sampling errors. These limitations highlight the unmet need for accurate noninvasive techniques to guide patient management. Girentuximab is a monoclonal antibody that targets carbonic anhydrase IX (CAIX), an enzyme highly expressed in clear cell renal carcinoma (ccRCC). Radiolabeled 89Zr-DFO-girentuximab (TLX250-CDx) is highly specific for CAIX and can aid differentiation between ccRCCs and other renal lesions. The ZIRCON study evaluated the performance of TLX250-CDx PET/CT for detection of ccRCC in adult patients with indeterminate renal masses (IDRM). Methods: ZIRCON was an open-label, multicenter clinical trial. Patients with an IDRM (≤ 7 cm; tumor stage cT1) who were scheduled for partial nephrectomy within 90 days from planned TLX250-CDx administration were eligible. Enrolled patients received a single dose of TLX250-CDx IV (37 MBq ± 10%; 10 mg girentuximab) on Day 0 and underwent PET/CT imaging on Day 5 (± 2 days) prior to surgery. Blinded central histology review determined ccRCC status. The coprimary objectives were to evaluate both the sensitivity and specificity of TLX250-CDx PET/CT imaging in detecting ccRCC in patients with IDRM, using histology as the standard of truth. Key secondary objectives included sensitivity and specificity of TLX250-CDx PET/CT imaging in the subgroup of patients with IDRM ≤ 4 cm (cT1a). Other secondary objectives included positive and negative predictive values, safety, and tolerability. The Wilson 95% confidence intervals (CI) lower bound for sensitivity and specificity had to be > 70% and 68% respectively for ≥ 2 independent readers to declare the study successful. Results: 300 patients received TLX250-CDx; mean age was 62 ± 12 y; 71% were males. Of 288 patients with central histopathology of surgical samples, 193 (67%) had ccRCC, and 179 (62%) had CT1a; Of 284 evaluable patients included in primary analysis, the average across all 3 readers for sensitivity and specificity was 86% [80%, 90%] and 87% [79%, 92%] respectively for coprimary endpoints; and 85% [77%, 91%] and 90% [79%, 95%] respectively for key secondary endpoints. For all readers, the lower boundaries of 95% CI for coprimary and key secondary endpoints were > 75%. For all evaluable patients, positive and negative predictive values were ≥ 91.7% and ≥ 73.7%, respectively. Of 263 treatment-emergent adverse events (TEAEs), 2 TEAEs were treatment related. Conclusions: This study confirms that TLX250-CDx PET/CT is well tolerated and can accurately and noninvasively identify ccRCC, with promising utility for designing best management approaches for patients with IDRM. Clinical trial information: NCT03849118 .

EVEREST: Everolimus for renal cancer ensuing surgical therapy—A phase III study (SWOG S0931, NCT01120249)

LBA4500

Background: Patients (pts) who undergo resection of renal cell carcinoma (RCC) with curative intent remain at risk for disease relapse. We conducted a phase III, double-blind, placebo (PB)-controlled, intergroup study to determine the effect of adjuvant treatment with the mTOR inhibitor everolimus (EVE) on recurrence-free survival (RFS). Methods: Pts with treatment-naïve, non-metastatic, fully-resected RCC at intermediate high- (pT1 G3-4 N0 to pT3a G1-2 N0) or very high-risk (pT3a G3-4 to pT4 G-any or N+) for recurrence were randomized 1:1 to EVE 10 mg PO daily x 54 weeks or PB within 12 weeks of radical or partial nephrectomy. Randomization was stratified by risk group, histology (clear vs. non-clear cell), and performance status (0 vs. 1). RFS was the primary end point; secondary endpoints included overall survival (OS) and adverse events (AEs). The study was designed to detect an 18% reduction in the risk of RFS with EVE compared to PB, corresponding to an improvement of median RFS from 6.75 (based on E2805 ASSURE) to 8.23 years. Final analysis, using a stratified logrank test, was to occur after 804 total events or by 3/2022, whichever occurred first. Results: Between 4/2011 and 9/2016, 1545 pts were randomized to EVE (n = 775) or PB (n = 770). Overall pt characteristics included: intermediate high-/very high-risk 45%/55%; clear cell/non-clear cell 83%/17%. The DSMC recommended study continuation after each of 4 pre-specified interim analyses. 556 DFS events among 1499 eligible pts occurred by the time of final study analysis on 2/23/2022. The median follow-up was 76 months. RFS was improved with EVE vs. PB (HR 0.85, 95% CI, 0.72 – 1.00; P1-sided= 0.0246), narrowly missing the pre-specified, one-sided significance level of 0.022 which accounted for interim analyses. Median RFS was not reached; the 6-year RFS estimate was 64% for EVE and 61% for PB. RFS improvement with EVE vs. PB was observed in the very high-risk group (HR 0.79, 95% 0.65-0.97; P1-sided= 0.011) but not in the intermediate high-risk group (HR 0.99, 95% CI 0.73-1.35, P1-sided= 0.48) ( P for interaction = 0.22). With 290 deaths, OS was similar between arms (HR 0.90, 95% CI, 0.71 – 1.13; P1-sided= 0.178). Fewer pts completed all 54 weeks of study treatment in the EVE group (45% v 69%). In the EVE group, 37% withdrew due to AEs (vs 5% in PB). Grade 3-4 AEs occurred in 46% of pts treated with EVE and 11% with PB. The most common grade 3-4 AEs were mucositis (14% v 0%), hypertriglyceridemia (11% vs. 2%), and hyperglycemia (5% vs. 0%). Conclusions: Adjuvant EVE improved RFS in RCC pts after nephrectomy, but the nominal significance level was narrowly missed. The RFS improvement was seen despite a high rate of early treatment discontinuation. A 21% improvement in RFS with EVE was observed in pts with very high-risk disease, a group for whom adjuvant therapy may be most relevant. Clinical trial information: NCT01120249.

CD70 is a promising CAR-T cell target in patients with advanced renal cell carcinoma

384

Background: Renal cell carcinoma (RCC) comprises a heterogeneous group of tumors of different histological subtypes. Each subtype is characterized by distinct immunohistochemical and molecular features and different biology. Currently, patients with advanced RCC have poor disease outcomes despite recent breakthroughs in immunotherapy. Chimeric antigen receptor (CAR)-T cell therapy has produced remarkably effective and durable clinical responses in hematological malignancies. However, there have been very limited success of CAR-T cell therapy in solid tumors. CD70 and its signaling partner CD27 are cell surface molecules that have emerged as novel targets for immune modulation approach. CD70 is also a promising target for CAR-T cell therapy, as it is overexpressed on multiple types of solid tumors including RCC and not expressed in most normal tissue. Studies have shown clear cell RCC (CCRCC) commonly expresses CD70. To date, no studies has evaluated CD70 expression in metastatic RCC in comparison with primary RCC. Methods: Four Tissue Microarrays (TMAs) were constructed using 395 tumors from 374 patients with RCC, 4 to 8 cores per tumor. There were 359 primary tumors, 36 metastatic tumors, and 344 matched normal. The primary RCC included 309 CCRCC including 11 with sarcomatoid differentiation, 38 papillary RCC (pRCC) including 1 with sarcomatoid differentiation, 8 chromophobe RCC (ChRCC), and 4 collecting duct RCC (CDC). The metastatic RCC were composed of 31 CCRCC including 3 with sarcomatoid differentiation and 5 PRCC. CD70 expression was evaluated using immunohistochemistry (IHC) and Definiens image analysis. CD70 expression was measured using the percentage of CD70-positive tumor cells. A CD70-positive tumor was defined as CD70 immunopercentage ≥ cutoff value in at least one core. Results: CD70 staining was detected in tumor cells in primary and metastatic RCC, with minimal staining in normal renal parenchyma. When the positive cutoff was defined as ≥1% of tumor cells demonstrating CD70 staining, the positive rate in CCRCC, pRCC, ChRCC, CDC, and SarRCC was 98%, 32%, 0%, 11%, and 46%, respectively. When the positive cutoff was defined as ≥ 25% of tumor cells stained positive for CD70, the positive rate in CCRCC, pRCC, ChRCC, CDC, and SarRCC was 41%, 10%, 0%, 0%, and 23%, respectively. Finally, when the positive cutoff was defined as ≥50%, the positive rate in CCRCC, pRCC, ChRCC, CDC, and SarRCC was 22%, 2%, 0%, 0%, and 8%, respectively. Metastatic RCC showed a higher % of tumor cells expressing CD70 compared to primary RCC for patients with CCRCC (mean 15% vs 9%) or SarRCC (12% vs 9%). Conclusions: Clear cell and sarcomatoid RCC are the RCC subtypes that demonstrate the highest CD70 expression. CD70 expression is further increased in metastatic lesions compared to the primary tumors. Anti-CD70 CAR-T cell therapy may benefit a significant fraction of patients with advanced CCRCC and sarcomatoid RCC.

Transcriptomic signatures can aid in post-operative risk stratification of clear cell renal cell carcinoma

383

Background: The ability to risk stratify patient’s post-nephrectomy is critical to select candidates for surveillance and adjuvant therapy. Whether transcriptomic information adds value to current prognostic information is unclear. Methods: Data from confirmed clear cell renal cell carcinoma (ccRCC) used in the TCGA Pan-RCC analysis was downloaded from cBioportal and GDC bioportal. Clinicopathologic variables were used to calculate the integrated staging system, SSIGN (stage, size, grade, and necrosis). The 16 gene recurrence score (RS) signature was generated as described in Rini 2015 using the TCGA data with log TPM normalization. The RS was stratified into high and low risk groups by median. SSIGN was divided into low (0-1) intermediate (2-4) and high ( > = 5) risk groups. RS and SSIGN prognostic significance were evaluated using disease recurrence as an end point, censoring by death. Results: SSIGN and recurrence scores (RS) were calculated for 369 (71.2%) of 518 available TCGA subjects with non-metastatic clear cell renal carcinoma. On multivariable analysis, the RS (continuous variable) was independently associated with disease-free status (HR 1.18 [95%CI (1.02-1.37)], p = 0.031) for each 10 point increase in RS) after adjusting for SSIGN. Categorizing SSIGN into low, intermediate and high-risk groups showed 3.9%, 18.5% and 39.8% 3-year recurrence rates. Stratifying SSIGN risk groups by RS scores we found an RS to further risk stratify the SSIGN intermediate risk group (HR 1.60 [95%CI 1.21-2.12], p < 0.001]). The AUC for at 3 years for SSIGN in the intermediate risk group was 0.68, for RS was 0.74 and the combination was 0.78 (with boot-strapping for optimism adjustment). At 3 years, patients with SSIGN intermediate risk disease (n = 135) with low RS had 3-year recurrence rate of 7.1% compared to 31.0% for those with high RS scores. Conclusions: Transcriptomic recurrence scores can risk stratify intermediate SSIGN clinical risk patients. Patients with intermediate risk disease but a high RS score had poorer outcomes similar to clinically high risk patients. Transcriptomic signatures may add value to existing clinicopathologic variables in ccRCC and clinical implementation is warranted.

SWOG S1931 (PROBE): Phase III randomized trial of immune checkpoint inhibitor (ICI) combination regimen with or without cytoreductive nephrectomy (CN) in advanced renal cancer

TPS402

Background: Kidney cancer presenting with synchronous primary tumor and metastases has demonstrated shorter survival outcome, as compared to the patients relapsing later with metastases after nephrectomy. CARMENA trial demonstrated no change in overall survival with addition of nephrectomy to sunitinib therapy. Immune checkpoint based combination therapy has now become the standard of care in frontline setting for RCC. The role of cytoreductive nephrectomy (CN) or primary resection has not been evaluated in the setting of immune checkpoint based systemic therapy. The PROBE study design attempts to answer the question whether CN has an impact on overall survival outcomes in advanced RCC within the context of immune checkpoint based combination regimens. The underlying mechanism is that the broader antigen spread and higher neoantigen load enabled by the primary tumor would enhance the efficacy of the immune therapy. CN after initial systemic therapy will potentially enable eradication of the immune resistant clones within the primary. Methods: Eligible patients with primary tumor and metastases are treated with one of the FDA approved ICI based combinations: ipililumab and nivolumab, axitinib and pembrolizumab, or axitinib and avelumab. Cabozantinib + nivolumab and lenvatinib + pembrolizumab combinations are being added into the next amendment. Urology evaluation and response assessment is required. Randomization occurs between 10-14 weeks of therapy; 1:1 to receive CN followed by systemic therapy or to continue on systemic therapy. The primary endpoint is overall survival. We estimate the median survival from time of randomization for the non-surgical arm will be 25 months. The study hypothesis is that CN will result in improvement in OS outcomes in advanced synchronous RCC post-initial systemic immune checkpoint based combination therapy. With a sample size of 302 eligible, randomized participants (151 per arm) and a one-sided alpha = 0.025, the study has 85% power to detect a 47% improvement in median survival (HR = 0.68; 1/0.68 = 1.47) Clinical trial information: NCT04510597.

Abstract P055: Targeting Krebs-cycle-deficient renal cell carcinoma with PARP inhibitor and low-dose alkylating chemotherapy

Loss-of-function mutations in genes encoding the Krebs cycle enzymes fumarate hydratase (FH) and succinate dehydrogenase (SDH) lead to excess accumulation of fumarate and succinate, respectively. Germline mutations in FH lead to a genetic predisposition to hereditary leiomyomatosis and renal cell cancer (HLRCC)-associated RCC. Similarly, loss-of-function alterations of SDH, most commonly SDHB, are associated with SDH-deficient neoplasms, including RCC. FH and SDHB deficient RCC tends to be aggressive and metastasize early with very limited treatment options. The oncometablites produced by these mutations, fumarate and succinate, competitively inhibit αKG-dependent dioxygenases, resulting in dysregulated DNA methylation and histone modification. We have previously demonstrated that elevated levels of fumarate and succinate both suppress the homologous recombination (HR) DNA-repair pathway through inhibition of the lysine demethylase KDM4B, resulting in aberrant hypermethylation of histone 3 lysine 9 (H3K9) at loci surrounding DNA breaks and masking a local H3K9 trimethylation signal that is essential for the proper execution of HR. In this study, we sought to identify novel treatment approaches that exploit genomic instability in FH- and SDHB-deficient RCC. Temozolomide (TMZ), an alkylating agent, mediates its cytotoxic effect by attaching methyl groups to DNA (O6-guanine, N7-guanine and N3-adenine). 16 N3-MetA and N7-MetG repair are mediated by the base excision repair (BER) in a process involving PARP. While the combination of PARP inhibitors with TMZ has been shown to increase TMZ-induced cytotoxicity, clinical trials investigating combination therapy have been hampered by significant toxicity. Using CRISPR/Cas9, we developed new syngeneic FH- and SDHB-deficient murine models of RCC. We demonstrate that FH- and SDHB-deficient cells have accumulation of fumarate and succinate leading to an increase in unresolved DNA double-strand breaks (DSBs). Treatment with PARP inhibition and temozolomide results in marked in vitro cytotoxicity in FH- and SDHB-deficient cells, even at low concentrations of TMZ (50 µM). In vivo, the combination of standard dose BGB-290 and low-dose TMZ (3mg/kg/dose) results in significantly delayed tumor progression in an SDHB deficient RENCA model without any significant increase in toxicity. Notably, the TMZ dose of 3mg/kg/dose is significantly lower than the 50mg/kg/dose that is commonly used for in vivo studies. Taken together, these findings provide the basis for a novel therapeutic strategy exploiting HR deficiency in FH and SDHB-deficient RCC with combined PARP inhibition and low-dose alkylating chemotherapy. Furthermore, the development of a new syngeneic mouse model provides a tool for the future study of immunotherapy in Krebs-cycle-deficient RCC.

Citation Format: Daiki Ueno, Amrita Sule, Jiayu Liang, Jinny van Doorn, Ranjini Sundaram, Randy Caliliw, Huihui Ye, Rong Rong Huang, Jing Li, Karla Boyd, Ranjit S. Bindra, Juan C. Vasquez, Brian M. Shuch. Targeting Krebs-cycle-deficient renal cell carcinoma with PARP inhibitor and low-dose alkylating chemotherapy [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P055.

Role of Imaging in Renal Cell Carcinoma: A Multidisciplinary Perspective

With the expansion in cross-sectional imaging over the past few decades, there has been an increase in the number of incidentally detected renal masses and an increase in the incidence of renal cell carcinomas (RCCs). The complete characterization of an indeterminate renal mass on CT or MR images is challenging, and the authors provide a critical review of the best imaging methods and essential, important, and optional reporting elements used to describe the indeterminate renal mass. While surgical staging remains the standard of care for RCC, the role of renal mass CT or MRI in staging RCC is reviewed, specifically with reference to areas that may be overlooked at imaging such as detection of invasion through the renal capsule or perirenal (Gerota) fascia. Treatment options for localized RCC are expanding, and a multidisciplinary group of experts presents an overview of the role of advanced medical imaging in surgery, percutaneous ablation, transarterial embolization, active surveillance, and stereotactic body radiation therapy. Finally, the arsenal of treatments for advanced renal cancer continues to grow to improve response to therapy while limiting treatment side effects. Imaging findings are important in deciding the best treatment options and to monitor response to therapy. However, evaluating response has increased in complexity. The unique imaging findings associated with antiangiogenic targeted therapy and immunotherapy are discussed. An invited commentary by Remer is available online. Online supplemental material is available for this article. ^©RSNA, 2021.

PROSPER: Phase III RandOmized Study Comparing PERioperative nivolumab versus observation in patients with renal cell carcinoma (RCC) undergoing nephrectomy (ECOG-ACRIN EA8143)

TPS4596

Background: There is no standard adjuvant systemic therapy that increases overall survival (OS) over surgery alone for non-metastatic RCC. Anti-PD-1 nivolumab (nivo) improves OS in metastatic RCC and is well tolerated. In mouse models, priming the immune system prior to surgery with anti-PD-1 results in superior OS compared to adjuvant dosing. Remarkable pathologic responses have been seen with neoadjuvant PD-1 in multiple ph 2 studies in bladder, lung and breast cancers. Phase 2 neoadjuvant RCC trials of nivo show preliminary feasibility and safety with no surgical delays. PROSPER RCC seeks to improve clinical outcomes by priming the immune system with neoadjuvant nivo prior to nephrectomy followed by continued immune system engagement with adjuvant blockade in patients (pts) with high risk RCC compared to standard of care surgery alone. Methods: This global, unblinded, phase 3 National Clinical Trials Network study is accruing pts with clinical stage ≥T2 or TanyN+ RCC of any histology planned for radical or partial nephrectomy. Select oligometastatic disease is permitted if the pt can be rendered ‘no evidence of disease’ within 12 weeks of nephrectomy (≤3 metastases; no brain, bone or liver). In the investigational arm, nivo is administered 480mg IV q4 weeks with 1 dose prior to surgery followed by 9 adjuvant doses. The control arm is nephrectomy followed by standard of care surveillance. There is no placebo. Baseline tumor biopsy is required only in the nivo arm but encouraged in both. Randomized pts are stratified by clinical T stage, node positivity, and M stage. 805 pts provide 84.2% power to detect a 14.4% absolute benefit in recurrence-free survival at 5 years assuming the ASSURE historical control of ̃56% to 70% (HR = 0.70). The study is powered to evaluate a significant increase in OS (HR 0.67). Critical perioperative therapy considerations such as safety, feasibility, and quality of life metrics are integrated. PROSPER RCC embeds a wealth of translational studies to examine the contribution of the baseline immune milieu and neoadjuvant priming with anti-PD-1 on clinical outcomes. As of February 10, 2021, 704 patients have been enrolled (N = 805). Clinical trial information: NCT03055013.

Sunitinib versus cabozantinib, crizotinib or savolitinib in metastatic papillary renal cell carcinoma (pRCC): Results from the randomized phase II SWOG 1500 study

270

Background: MET signaling is a key molecular driver in pRCC. Given that there is no optimal therapy for metastatic pRCC, we sought to compare an existing standard (sunitinib) to putative MET kinase inhibitors. Methods: Eligible patients had pathologically verified pRCC, Zubrod performance status 0-1, and measurable metastatic disease. Patients may have received up to 1 prior systemic therapy excluding VEGF-directed agents. Patients were randomized 1:1:1:1 to receive either sunitinib 50 mg po qd (4 wks on/2 wks off), cabozantinib 60 mg po qd, crizotinib 250 mg po bid, or savolitinib 600 mg po qd. Patients were stratified by prior therapy and pRCC subtype (I vs II vs not otherwise specified [NOS]) based on local review. The primary objective was to compare progression-free survival (PFS) for each experimental arm versus sunitinib. With 41 eligible patients per arm, we estimated 85% power to detect a 75% improvement in median PFS with a 1-sided alpha of 0.10 using intent-to-treat analysis. A pre-planned futility analysis was performed after 50% of PFS events occurred. Secondary endpoints included toxicity, response rate, and overall survival. Results: Between 4/2016 and 12/2019, 152 patients were enrolled; 5 were ineligible. Median age was 66 (range:29-89) and 76% were male; 92% had no prior therapy. By local pathologic review, 18%, 54% and 28% of patients were characterized as having type I, type II and NOS histology, respectively. In contrast, the frequency of type I, type II, and NOS by central review was 30%, 45% and 25%, respectively. Accrual to the savolitinib and crizotinib arms was halted early for futility (PFS hazard ratio > 1.0 for both); accrual continued to completion in the sunitinib and cabozantinib arms. Median PFS was significantly higher with cabozantinib relative to sunitinib (Table). Grade 3 or 4 adverse events occurred in 69%, 72%, 37% and 39% of patients receiving sunitinib, cabozantinib, crizotinib and savolitinib, respectively; one grade 5 adverse event was seen with cabozantinib. Overall survival and response data will be presented. Conclusions: In this multi-arm randomized trial, only cabozantinib resulted in a statistically significant and clinically meaningful prolongation of PFS in pRCC patients compared to sunitinib. These data support cabozantinib as a reference standard for eligible patients with metastatic pRCC. Clinical trial information: NCT02761057 . [Table: see text]

Analysis of guideline recommended use of renal mass biopsy and association with treatment

INTRODUCTION

Renal mass biopsy (RMB) may not be indicated when the results are unlikely to impact management, such as in young and/or healthy patients and in elderly and/or frail patients. We analyzed the utility of RMB in three patient cohorts stratified by age-adjusted Charlson comorbidity index score (ACCI).

MATERIALS AND METHODS

We identified patients with cT1a renal tumors in the National Cancer Database from 2004-2014. We combined age and Charlson-Deyo scores to identify young and/or healthy patients ('healthy-ACCI'), elderly and/or frail patients ('frail-ACCI'), and a reference cohort. We performed multivariable logistic regression to identify predictors of RMB and treatment. We evaluated the impact of RMB on management by analyzing the proportion of high-grade disease on final pathology as a surrogate for risk stratification.

RESULTS

We identified 36,720 healthy-ACCI, 2,516 frail-ACCI, and 18,989 reference-ACCI patients. Healthy-ACCI patients were less likely to undergo RMB (7.5% versus 10.8%; p < 0.001) while frail-ACCI patients underwent RMB at similar rates (11.8% versus 10.8%; p = 0.14) compared with reference-ACCI patients. On multivariable logistic regression, in both healthy-ACCI and frail-ACCI patients, RMB was associated with decreased odds of surgical treatment, and increased odds of ablation and surveillance (all p < 0.01). In the frail-ACCI patients, higher grade disease at surgery was identified in the RMB cohort (32.9% versus 23.5%, p = 0.05).

CONCLUSIONS

RMB is performed less frequently in healthy-ACCI patients compared with the reference cohort. RMB is associated with decreased odds of surgical treatment and increased odds of surveillance and ablation in all cohorts. In frail-ACCI patients who underwent surgery, RMB may provide additional risk stratification as these patients had lower rates of low-grade disease.

Oncometabolites suppress DNA repair by disrupting local chromatin signalling

Deregulation of metabolism and disruption of genome integrity are hallmarks of cancer1. Elevated levels of the metabolites, 2-hydroxyglutarate (2HG), succinate, and fumarate, occur in human malignancies due to somatic mutations in the isocitrate dehydrogenase-1/2 (IDH1/2) genes or germline mutations in the fumarate hydratase (FH) and succinate dehydrogenase (SDH) genes, respectively^2–4. Recent work has made an unexpected connection between these metabolites and DNA repair by showing that they suppress the pathway of homology-dependent repair (HDR)^5,6 and confer an exquisite sensitivity to poly (ADP-ribose) polymerase (PARP) inhibitors that is being tested in clinical trials. However, the mechanism by which these oncometabolites inhibit HDR remains poorly understood. Here we elucidate the pathway by which these metabolites disrupt DNA repair. We show that oncometabolite-induced inhibition of the lysine demethylase KDM4B results in aberrant hypermethylation of histone 3 lysine 9 (H3K9) at loci surrounding DNA breaks, masking a local H3K9 trimethylation signal that is essential for the proper execution of HDR. Consequently, recruitment of Tip60 and ATM, two key proximal HDR factors, is significantly impaired at DNA breaks, with reduced end-resection and diminished recruitment of downstream repair factors. These findings provide a mechanistic basis for oncometabolite-induced HDR suppression and may guide effective strategies to exploit these defects for therapeutic gain.

PROSPER: Phase III randomized study comparing perioperative nivolumab versus observation in patients with renal cell carcinoma (RCC) undergoing nephrectomy (ECOG-ACRIN EA8143)

TPS5101

Background: There is no standard adjuvant systemic therapy that increases overall survival (OS) over surgery alone for non-metastatic RCC. Anti-PD-1 nivolumab (nivo) improves OS in metastatic RCC and is well tolerated. In mouse models, priming the immune system prior to surgery with anti-PD-1 results in superior OS compared to adjuvant dosing. Remarkable pathologic responses have been seen with neoadjuvant PD-1 in multiple ph 2 studies in bladder, lung and breast cancers. Phase 2 neoadjuvant RCC trials of nivo show preliminary feasibility and safety with no surgical delays. PROSPER RCC seeks to improve clinical outcomes by priming the immune system with neoadjuvant nivo prior to nephrectomy followed by continued immune system engagement with adjuvant blockade in patients (pts) with high risk RCC compared to standard of care surgery alone. Methods: This global, unblinded, phase 3 National Clinical Trials Network study is accruing pts with clinical stage ≥T2 or TanyN+ RCC of any histology planned for radical or partial nephrectomy. Select oligometastatic disease is permitted if the pt can be rendered ‘no evidence of disease’ within 12 weeks of nephrectomy (≤3 metastases; no brain, bone or liver). In the investigational arm, nivo is administered 480mg IV q4 weeks with 1 dose prior to surgery followed by 9 adjuvant doses. The control arm is nephrectomy followed by standard of care surveillance. There is no placebo. Baseline tumor biopsy is required only in the nivo arm but encouraged in both. Randomized pts are stratified by clinical T stage, node positivity, and M stage. 805 pts provide 84.2% power to detect a 14.4% absolute benefit in recurrence-free survival at 5 years assuming the ASSURE historical control of ~56% to 70% (HR = 0.70). The study is powered to evaluate a significant increase in OS (HR 0.67). Critical perioperative therapy considerations such as safety, feasibility, and quality of life metrics are integrated. PROSPER RCC embeds a wealth of translational studies to examine the contribution of the baseline immune milieu and neoadjuvant priming with anti-PD-1 on clinical outcomes. As of February 2020, 396 patients have been enrolled. Clinical trial information: NCT03055013 .

Results from a phase II study of bevacizumab and erlotinib in subjects with advanced hereditary leiomyomatosis and renal cell cancer (HLRCC) or sporadic papillary renal cell cancer

5004

Background: HLRCC is a familial cancer syndrome associated with a type 2 papillary RCC (pRCC) variant. HLRCC is caused by germline mutations in the gene for the Krebs cycle enzyme fumarate hydratase (FH). FH inactivation results in VHL-independent upregulation of hypoxia inducible factor, a reliance on aerobic glycolysis, and activation of the NRF2 pathway, features also shared by some sporadic pRCC tumors. We hypothesized that the metabolic alterations underlying these tumors would be susceptible to targeted therapy with a combination of bevacizumab and erlotinib. Methods: Patients with advanced pRCC were eligible to enroll on this phase II study. To enrich for patients with FH deficiency, those with 1) HLRCC and 2) sporadic pRCC were enrolled into parallel, independent cohorts. All patients received bevacizumab 10 mg/kg IV every 2 weeks and erlotinib 150 mg orally daily. Patients who had received no more than two agents targeting the VEGFR pathway were included. Patients remained on treatment until unacceptable toxicity or progression. The primary endpoint was overall response rate (ORR); secondary endpoints were progression free survival (PFS) and duration of response. Results: A total of 83 patients with pRCC, including 42 in the HLRCC cohort and 41 in the sporadic cohort were enrolled on study. The majority of patients were IMDC intermediate risk (53/83, 64%) and 27 (33%) had at least one prior treatment. The ORR was 51% (42/83; 95% CI, 40 – 61) in all patients, 64% (27/42; 95% CI, 49 – 77) in the HLRCC cohort, and 37% (15/41; 95% CI, 24 – 52) in the sporadic cohort. The median PFS was 14.2 months (95% CI, 11.4 – 18.6) in all patients, 21.1 months (95% CI, 15.6 – 26.6) in the HLRCC cohort, and 8.7 months (95% CI, 6.4 – 12.6) in the sporadic cohort. The majority of treatment related adverse events (TRAEs) were grade 1 or 2 with the most common being acneiform rash (92%), diarrhea (77%), proteinuria (71%), and dry skin (61%). Grade ≥3 TRAEs occurred in 47% of patients, including hypertension (34%) and proteinuria (13%), with one patient (1.2%) with a grade 5 GI hemorrhage possibly related to bevacizumab. Conclusions: The combination of bevacizumab and erlotinib is well tolerated and is associated with encouraging activity in advanced pRCC, particularly in patients with FH deficient tumors. This is the first and largest prospective study in HLRCC and provides the basis for considering bevacizumab and erlotinib as a preferred option in a patient population that has no widely accepted standard. Clinical trial information: NCT01130519 .

Minimally invasive partial nephrectomy versus percutaneous cryoablation for stage Ia renal cell carcinoma: A cost-effectiveness analysis

e17066

Background: Minimally invasive partial nephrectomy (PN) and percutaneous cryoablation (Cryo) are treatment strategies for renal cell carcinoma (RCC). The purpose of this study is to assess the cost-effectiveness of PN and Cryo for stage Ia RCC. Methods: A decision-analysis model was constructed over 5 years from a health care sector’s perspective using TreeAge Pro Suite 2019 (TreeAge Software LLC, Cambridge, MA). The two evaluated strategies were PN and Cryo. The model incorporated the clinical course of stage Ia RCC after either treatment, including costs and quality of life associated with major complications, imaging surveillance (based on 2014 National Comprehensive Cancer Network guidelines), local and metastatic recurrences, and cancer-specific mortality. All clinical parameters were derived from the literature. A willingness-to-pay threshold of $100,000/quality adjusted life year (QALY) was used. 1 QALY is equivalent to 1 year of life in perfect health. Outcomes were measured by incremental effectiveness ratio. Base case calculations, Monte Carlo Simulations with 10,000 iterations using bootstrapping for parameters from their distributions, and multiple sensitivity analyses were performed. Results: Five-year local recurrence-free, metastasis-free, and cancer-specific survival from recent literature were 97.7% versus 95.9% ( p = 0.18), 98.0% versus 100% ( p = 0.14), 99.3% versus 100% % ( p = 0.7) for PN and Cryo. PN and Cryo yielded similar health benefits of 3.63 QALY and 3.64 QALY. Overall costs were $26,343 and $19,346 for PN and Cryo. A total of 89.28% of the 10,000 simulations showed higher cost-effectiveness of Cryo than PN. One-way sensitivity analyses varying long-term outcomes after Cryo while keeping outcomes after PN constant, revealed that Cryo is more cost-effective than PN when its local recurrence risk is < 3.94% per year (18.2% over 5 years), metastasis risk is < 1.51% per year (7.33% over 5 years), or cancer-specific mortality risk is < 0.96% per year (4.7% over 5 years). PN is more cost-effective if Cryo local recurrence risk is 3.5% higher than PN per year, when the metastasis risk is 1.1% higher than PN per year, or when its cancer-specific mortality is more than 0.9% higher than PN per year. Cryo is more cost-effective than PN if its cost is not more than $1,000 higher than PN. Conclusions: Our study showed that Cryo is more cost-effective than PN for stage Ia RCC patients with comparable effectiveness at a lower cost, based on multiple probabilistic and deterministic sensitivity analyses.

Clinically advanced renal cell carcinoma (RCC) and renal sarcoma (RSC) in young patients: A comprehensive genomic profiling (CGP) study

5066

Background: We queried whether the landscape of genomic alterations (GA) would differ in patients with metastatic RCC under 40 years of age (under40) and patients 40 years of age or older (over40). Methods: FFPE tissues from 2,128 clinically advanced RCC and 25 RSC underwent hybrid-capture based CGP to evaluate all classes of GA. Samples were classified at time of sequencing as the following RCC subtypes: clear cell (ccRCC), papillary (papRCC), chromophobe (chrRCC), medullary (medRCC), collecting duct (cdRC), sarcomatoid (sarcRCC) and NOS (nosRCC). Tumor mutational burden (TMB) was determined on up to 1.1 Mbp of sequenced DNA. Tumor cell PD-L1 expression was determined by IHC (Dako 22C3). Results: The male preponderance increased in the over40 patients. The GA/tumor increased in the over40 cohorts except for medRCC. Similarly, TMB was consistently higher in over40 groups. MSI high status was virtually absent. PD-L1 expression, available only in small subsets, was generally absent although 44% high positive staining in sarcRCC was noteworthy. Differences in GA in under40 vs over40 RCC were seen and included increased PBRM1 and SETD2 GA in over40 vs under40 ccRCC; increased C DKN2A/B and TERT and decreased FH GA in over40 vs under40 papRCC; increased TP53 and decreased VHL, BAP1, SETD2 and PTEN in over40 vs under40 chrRCC; increased TP53, PTEN and TERT GA with decreased NF2 GA in over40 vs under 40 sarcRCC; and increased TP53, VHL and TERT in over40 vs under40 nosRCC. Changes in GA in under40 vs over40 medRCC, cdRCC and RSC were noted but insufficient cases prevented further evaluation. Conclusions: When separately evaluated by under/over 40 years of age, CGP of clinically advanced RCC demonstrates differences in genomic landscapes with over40 cases featuring increasing male preponderance, higher GA/tumor, higher TMB and increases in a variety of GA. These findings may play important roles in the planning of future clinical trials designed to personalize the treatment of metastatic RCC. [Table: see text]

Fear of cancer recurrence among patients and survivors diagnosed with localized renal cell carcinoma

649

Background: Fear of cancer recurrence (FCR) is considered one of the most pervasive and burdensome sources of distress for patients. Whereas it can be considered an adaptive response to real threats associated with diagnosis, treatment and disease, numerous studies have suggested that elevated levels can be dysfunctional. Despite this extensive body of research, little is known regarding FCR among individuals diagnosed with renal cell carcinoma (RCC). The current study sought to describe the prevalence of FCR among patients with RCC. Methods: Patients with localized RCC participated in an international survey from 07/19 to 09/19, through an online platform devised by a non-profit patient advocacy group (KCCure). Patients were assessed for FCR using the FCR-7, a 7-item measure, ranging from 0 to 28. A cutoff score of 17 indicates a moderate level of FCR, while a cutoff of 27 indicates severe level of FCR. Linear regression was used to determine the association between FCR and patients’ characteristics. Results: A total of 1150 patients participated in this survey, of which 412 had localized disease and were assessed for FCR. The majority were female (79%), with a median age of 54 years old (range, 30-80), and well-educated (58%). Patients were predominantly from US (85%), Canada (4%) and Germany (2%) and lived in suburban (48%) or rural areas (32%). More than half of participants were diagnosed with disease stage I (56%) and the remainder were divided between stage II (19%) and III (24%). More than half of patients (55%) reported a moderate or severe level of FCR. Younger patients (p=0.001) and those of female gender (p=0.004) were more likely to report higher levels of FCR. Conclusions: To our knowledge, this is the first study to quantify the degree of FCR among patients and survivors diagnosed with localized RCC. Importantly, high rates of FCR were associated with female gender and younger age, possibly driven by the fact that women may be more open to disclosing emotional symptoms and younger patients are still to pass through many life milestones and thus fear may be more pronounced. Targeted assessment and interventions are needed to address this highly prevalent form of distress among those diagnosed with RCC.

PROSPER: Phase III randomized study comparing perioperative nivolumab versus observation in patients with renal cell carcinoma (RCC) undergoing nephrectomy (ECOG-ACRIN EA8143)

TPS765

Background: There is no standard adjuvant systemic therapy that increases overall survival (OS) over surgery alone for non-metastatic RCC. Anti-PD-1 nivolumab (nivo) improves OS in metastatic RCC and is well tolerated. In mouse models, priming the immune system prior to surgery with anti-PD-1 results in superior OS compared to adjuvant dosing. Remarkable pathologic responses have been seen with neoadjuvant PD-1 in multiple ph 2 studies in bladder, lung and breast cancers. Phase 2 neoadjuvant RCC trials of nivo show preliminary feasibility and safety with no surgical delays. PROSPER RCC seeks to improve clinical outcomes by priming the immune system with neoadjuvant nivo prior to nephrectomy followed by continued immune system engagement with adjuvant blockade in patients (pts) with high risk RCC compared to standard of care surgery alone. Methods: This global, unblinded, phase 3 National Clinical Trials Network study is accruing pts with clinical stage ≥T2 or TanyN+ RCC of any histology planned for radical or partial nephrectomy. Select oligometastatic disease is permitted if the pt can be rendered ‘no evidence of disease’ within 12 weeks of nephrectomy (≤3 metastases; no brain, bone or liver). In the investigational arm, nivo is administered 480mg IV q4 weeks with 1 dose prior to surgery followed by 9 adjuvant doses. The control arm is nephrectomy followed by standard of care surveillance. There is no placebo. Baseline tumor biopsy is required only in the nivo arm but encouraged in both. Randomized pts are stratified by clinical T stage, node positivity, and M stage. 805 pts provide 84.2% power to detect a 14.4% absolute benefit in recurrence-free survival at 5 years assuming the ASSURE historical control of ~56% to 70% (HR = 0.70). The study is powered to evaluate a significant increase in OS (HR 0.67). Critical perioperative therapy considerations such as safety, feasibility, and quality of life metrics are integrated. PROSPER RCC embeds a wealth of translational studies to examine the contribution of the baseline immune milieu and neoadjuvant priming with anti-PD-1 on clinical outcomes. As of October 18, 2019, 317 patients have been enrolled. Clinical trial information: NCT03055013.

Genetic risk assessment for hereditary RCC: Report from the consensus panel meeting

615

Background: While many genes are now known to be associated with hereditary kidney cancer syndromes, there is a paucity of guidelines or uniform consensus on genetic testing for these patients. An expert panel was organized to assess who, what, when and how patients should be evaluated and what testing should be initiated. Methods: A national, multidisciplinary, panel of experts in urology, medical oncology, clinical geneticists, genetic counselors and patient advocates with background and knowledge in hereditary syndromic kidney cancer convened in person in September 2019. A renal cell carcinoma (RCC) genetic risk assessment questionnaire consisting of 52 questions was compiled prior to the meeting using modified Delphi methodology. The questions were then discussed and reviewed with uniform consensus defined as a minimum of 85% agreement in accordance with the National Comprehensive Cancer Network criteria. Results: The panel consisted of twenty-six attendees represented by urologists (43%), medical oncologist (23%), genetic counselors (13%), clinical geneticists (7%), and patient advocates (3%). The questionnaire consisted of fifty-five statements focusing on who, what, when and how genetic testing should be performed in a patient suspected of hereditary RCC syndrome. A >85% agreement was reached on 30/52 statements with 18/25 (72%) achieving consensus addressing “who”, 2/6 (33%) achieving consensus in “what’ category, 2/7 (29%) in ‘when’ and 4/6 (67%) on how. The questions with least consensus were found in the “what/when?” category with only 4/13 questions with minimum 85% agreement. Specific areas of debate included an age cutoff for prompting a genetic risk assessment as well as need for familial testing in patients with variants of unknown significance. Conclusions: Despite experience of the panel in management of hereditary RCC, the consensus was reached only on 66% of genetic testing. While many issues will need to be discussed further, those statements with consensus may be used to guide physicians and patients on who, what, when and how genetic RCC risk assessment should be performed.

Development of a 2-dimensional atlas of the human kidney with imaging mass cytometry

An incomplete understanding of the biology of the human kidney, including the relative abundances of and interactions between intrinsic and immune cells, has long constrained the development of therapies for kidney disease. The small amount of tissue obtained by renal biopsy has previously limited the ability to use patient samples for discovery purposes. Imaging mass cytometry (IMC) is an ideal technology for quantitative interrogation of scarce samples, permitting concurrent analysis of more than 40 markers on a single tissue section. Using a validated panel of metal-conjugated antibodies designed to confer unique signatures on the structural and infiltrating cells comprising the human kidney, we performed simultaneous multiplexed imaging with IMC in 23 channels on 16 histopathologically normal human samples. We devised a machine-learning pipeline (Kidney-MAPPS) to perform single-cell segmentation, phenotyping, and quantification, thus creating a spatially preserved quantitative atlas of the normal human kidney. These data define selected baseline renal cell types, respective numbers, organization, and variability. We demonstrate the utility of IMC coupled to Kidney-MAPPS to qualitatively and quantitatively distinguish individual cell types and reveal expected as well as potentially novel abnormalities in diseased versus normal tissue. Our studies define a critical baseline data set for future quantitative analysis of human kidney disease.

PROSPER: A phase III randomized study comparing perioperative nivolumab (nivo) versus observation in patients with renal cell carcinoma (RCC) undergoing nephrectomy (ECOG-ACRIN 8143)

TPS4597

Background: The anti-PD-1 antibody nivo improves overall survival (OS) in metastatic RCC and is well tolerated. There is no standard adjuvant (adjuv) systemic therapy that increases OS over surgery alone for non-metastatic RCC. Priming the immune system prior to surgery with anti-PD-1 has shown an OS benefit compared to a pure adjuv approach in mouse solid tumor models. Multiple ph 2 studies in bladder, lung and breast cancers have shown remarkable pathologic responses with neoadjuvant (neoadj) PD-1 blockade. Two ongoing ph 2 studies of perioperative nivo in M0 RCC patients are showing preliminary feasibility and safety with no surgical delays (NCT02575222; NCT02595918). PROSPER RCC (NCT03055013) aims to improve clinical outcomes by priming the immune system prior to nephrectomy with neoadj nivo and continued engagement with adjuv blockade in patients with high risk RCC compared to surgery alone. Methods: This global, unblinded, phase 3 National Clinical Trials Network study is currently accruing patients with clinical stage ≥T2 or TanyN+ RCC of any histology planned for nephrectomy. Oligometastases are permitted if can be rendered NED. We amended the study to enhance accrual and patient quality of life by changing nivo dosing to 480mg q4 wks and requiring baseline tumor biopsy only in the nivo arm. The investigational arm receives 1 dose of nivo prior to surgery followed by 9 adjuv doses. The control arm undergoes standard nephrectomy followed by observation. Randomized patients are stratified by clinical T stage, node positivity, and M stage. Accrual of 805 patients provides 84.2% power to detect a 14.4% absolute benefit in recurrence-free survival (RFS) at 5 years assuming the ASSURE historical control of ~56% to 70% (HR = 0.70). The study is powered to evaluate a significant increase in OS (HR 0.67). Critical perioperative therapy considerations such as safety, feasibility, and quality of life endpoints have been integrated. PROSPER RCC embeds a wealth of translational work aimed at investigating the impact of the baseline immune milieu, the changes induced by neoadjuvant anti-PD-1 priming, and how both may predict clinical outcomes. Clinical trial information: NCT03055013.

The future of perioperative therapy in advanced renal cell carcinoma: how can we PROSPER?

Patients with high-risk renal cell carcinoma (RCC) experience high rates of recurrence despite definitive surgical resection. Recent trials of adjuvant tyrosine kinase inhibitor therapy have provided conflicting efficacy results at the cost of significant adverse events. PD-1 blockade via monoclonal antibodies has emerged as an effective disease-modifying treatment for metastatic RCC. There is emerging data across other solid tumors of the potential efficacy of neoadjuvant PD-1 blockade, and preclinical evidence supporting a neoadjuvant over adjuvant approach. PROSPER RCC is a Phase III, randomized trial evaluating whether perioperative nivolumab increases recurrence-free survival in patients with high-risk RCC undergoing nephrectomy. The neoadjuvant component, intended to prime the immune system for enhanced efficacy, distinguishes PROSPER from other purely adjuvant studies and permits highly clinically relevant translational studies.

PROSPER: A phase III randomized study comparing perioperative nivolumab (nivo) versus observation in patients with localized renal cell carcinoma (RCC) undergoing nephrectomy (ECOG-ACRIN 8143)

TPS684

Background: The anti-PD-1 antibody nivo improves overall survival in metastatic RCC and is well tolerated. There is no standard adjuvant systemic therapy that increases overall survival (OS) over surgery alone for non-metastatic RCC. Priming the immune system prior to surgery with anti-PD-1 has shown an OS benefit compared to a pure adjuvant approach in mouse solid tumor models. The PROSPER RCC trial aims to improve clinical outcomes by priming the immune system prior to nephrectomy with neoadjuvant nivo and continued engagement with adjuvant blockade in patients with high risk M0 RCC compared to surgery alone. Methods: This global, unblinded, phase 3 National Clinical Trials Network study is currently accruing patients with clinical stage ≥T2 or node positive M0 RCC of any histology. Tumor biopsy prior to randomization is mandatory to ensure RCC and permits in depth correlative science. The investigational arm will receive two doses of nivo 240mg prior to surgery followed by adjuvant nivo for 9 months (q2 wks x 3 mo followed by 480mg q4 wks x 6 mo). The control arm will undergo standard nephrectomy followed by observation. Randomized patients are stratified by clinical T stage, node positivity, and histology. To enhance accrual and patient quality of life, key upcoming amendments are being instituted. These include biopsy only in the nivo arm, allowance of oligometastatic disease and bilateral renal masses that can be fully resected/ablated, and change of nivo dosing to q4 wks (1 neoadj; 9 adj). With accrual of 766 patients, there is 84.2% power to detect a 14.4% absolute benefit in recurrence-free survival (RFS) at 5 years assuming the ASSURE historical control of ~56% to 70% (HR = 0.70). The study is also powered to evaluate a significant increase in overall survival (HR 0.67). Safety, feasibility, and quality of life endpoints critical to adjuvant therapy considerations are incorporated. PROSPER RCC embeds a wealth of translational work aimed at investigating the impact of the baseline immune milieu, the changes induced by neoadjuvant anti-PD-1 priming, and how both correlate with clinical outcomes. Clinical trial information: NCT03055013.

The nonsurgical management of upper tract urothelial carcinoma: A role for active surveillance?

485

Background: Approximately 7% of patients with localized upper tract urothelial cancer (UTUC) are treated without definitive therapy. Understanding outcomes and alternative therapy would aid in counseling older patients with co-morbidities. Methods: We utilized the National Cancer Database to identify patients with localized UTUC managed non-surgically between 2004 and 2013. Patient demographics, co-morbidity, tumor grade, and chemotherapy and radiation utilization were recorded. Survival analyses were performed with the Kaplan-Meier method and a cox proportional hazard regression model. Results: We identified 3,157 (10.9%) patients with localized UTUC who did not receive definitive surgery. Median age was 79 years, 55% were males, 79% had government health insurance, and 68% had a CDS of 0. Tumor grade was low (grade 1 or 2) in 632 (36.4%) and high (grade 3 or 4) in 1104 (63.6%). Median overall survival (OS) for the cohort was 2.2 years, significantly shorter for patients with greater co-morbidities. Chemotherapy or radiation was performed in 294 (9.3%) and 197 (6.3%) patients respectively. There were no OS differences for individuals receiving chemotherapy. Of patients who received radiation therapy, the median OS was 1.4 vs 2.0 years, (p<0.001) favoring no radiation. Those with high grade tumors had worse survival (1.9 vs 3.8 years (p<0.001). Significant predictors of shorter OS included older age, male gender, higher CDS, and government insurance. Conclusions: In this population-based cohort, 10.9% of patients with localized UTUC were managed non-surgically. Radiation and chemotherapy were not routinely utilized, and did not demonstrate improved survival. Median OS was significantly shorter for those with higher grade disease, increasing co-morbidity profile, male gender, and those with government insurance status.

Sporadic angiomyolipomas (AMLs) growth kinetics while on everolimus (SAGE)

560

Background: Level I evidence exists demonstrating the efficacy of the mTOR inhibitor everolimus (EVE) in decreasing tumor volume of syndromic angiomyolipomas (AMLs) among patients with Tuberous Sclerosis. No prospective data are available regarding the effect of mTOR inhibition on growth kinetics in patients with sporadic AMLs. Methods: We conducted a multi-institutional, prospective, phase 2 trial with an optimal two-stage Simon design in patients presenting with > 3cm sporadic AMLs who were candidates for surgical or percutaneous intervention. Response was defined as ≥25% volumetric reduction of the AML. Planned enrollment was 43 patients to test the null hypothesis at a 5% level of significance with 80% power. Baseline, 4- and 6-month volumetric analysis was performed by dynamic contrast-enhanced MRI (DCE-MRI). Patients received EVE 10mg for four 28-day cycles, at which point EVE was discontinued in those with < 25% volumetric reduction. Those with ≥ 25% volumetric reduction received two additional cycles of EVE. Dose reductions and interruptions were allowed to 5 mg QOD. Conservative stopping rules were established for toxicity, given the benign nature of AMLs. Results: The early stopping rules for both efficacy and toxicity were invoked. We enrolled 20 patients (median age = 68) from 5 centers with 21 sporadic AMLs. 11/20 (55%) patients completed 4 cycles of EVE, while 7/20 (35%) completed 6 cycles. Median days on treatment was 88 (2 cycles). 4/20 (20%) patients were withdrawn due to toxicity, while 8/20 (40%) withdrew due to personal preference. Dose reductions were required in 6/20 (30%) patients, and 5/20 (25%) patients had grade 3 toxicities which resolved upon discontinuation or dose reduction of EVE. At 4-month MRI, 10/16 (62.5%) patients had a ≥25% reduction in volume (mean = 54.1% decrease). At 6-month MRI, 8/12 (66.6%) patients had a ≥25% reduction in volume (mean = 51.5% decrease). Conclusions: EVE was effective in reducing tumor volume in patients with sporadic AMLs but was associated with a high rate of treatment termination due to patient preference or prespecified AEs. Neoadjuvant EVE may be useful in potentiating surgical resection of large or anatomically complex AMLs. Clinical trial information: NCT02539459.

National trends in the management of patients with positive surgical margins at the time of radical prostatectomy

111

Background: The optimal management approach for patients with positive surgical margins (PSM) at radical prostatectomy (RP) has not been definitively assessed. To better understand contemporary patterns of care, we sought to examine time trends and determinants of adjuvant therapy in a large national sample of men with prostate cancer (PCa) treated with RP. Methods: We queried the National Cancer Database (NCDB) to identify men with clinically-localized PCa diagnosed from 2010 to 2014 who had PSM at RP performed as initial primary definitive treatment. We used descriptive statistics to examine subsequent management strategies, assessed as no adjuvant therapy as part of the initial planned course of management, receipt of adjuvant radiation therapy (RT), and receipt of adjuvant RT in combination with androgen deprivation therapy (ADT). Binary logistic regression models were constructed to identify patient, tumor, and facility features associated with receipt of adjuvant therapy. Results: During the study period, we identified 44,523 patients with PSM. Of those, 5,179 (11.6%) men received any adjuvant RT (+/- ADT), while only 1,380 (3%) received adjuvant RT with ADT. Use of adjuvant RT did not change over the study period ( p= 0.61). On multivariable analysis men of uninsured status (p = 0.003), Medicaid insurance (p = 0.001), and patients treated in non-academic facilities (p < 0.001) were more likely to receive adjuvant RT. In addition, use of adjuvant RT was associated with higher pre-treatment PSA (p < 0.001), pathologic stage (p < 0.001) and Gleason grade group (p < 0.001), decreasing distance from the treatment center (p < 0.001), and shorter duration between diagnosis and RP (p < 0.001). Receipt of adjuvant ADT with RT was associated with clinical and pathologic features; however, not with sociodemographic factors. Conclusions: The majority of patients experiencing PSM at RP did not receive adjuvant RT, and rates of adjuvant therapy have remained stable over time. In addition to adverse clinical and pathologic features, sociodemographic and facility factors were significantly associated with receipt of adjuvant RT; however, the addition of ADT appears largely driven by disease characteristics.

A phase III randomized study comparing perioperative nivolumab vs. observation in patients with localized renal cell carcinoma undergoing nephrectomy (PROSPER RCC)

TPS710

Background: The anti-PD-1 antibody nivolumab (nivo) improves overall survival (OS) in metastatic treatment refractory RCC and is generally tolerable. In 2017, there is no standard adjuvant therapy proven to increase OS over surgery alone in non-metastatic (M0) disease. Mouse solid tumor models have revealed an OS benefit with a short course of neoadjuvant PD-1 blockade compared to adjuvant therapy. Two ongoing phase 2 studies of perioperative nivo in RCC patients (pts) are showing preliminary feasibility and safety with no surgical delays/complications. PROSPER RCC will examine if the addition of perioperative nivo to radical or partial nephrectomy can improve clinical outcomes in pts with locally advanced RCC. We are implementing a three-pronged, multidisciplinary approach of presurgical priming with nivo followed by resection and adjuvant PD-1 blockade with the goal of increasing cure and recurrence-free survival (RFS) rates in M0 RCC. Methods: Tumor biopsy prior to randomization is mandatory to ensure RCC diagnosis but will also permit unparalleled correlative science in this global, unblinded, phase 3 National Clinical Trials Network randomized study. 766 pts with clinical stage ≥T2 or any node positive M0 RCC of any histology will be enrolled. The study arm will receive nivo 240mg IV for 2 doses prior to surgery followed by adjuvant dosing for 9 mo (q2 wks x 3 mo followed by q4 wks x 6 mo). The control arm will undergo the current standard of care: surgical resection followed by observation. Pts are stratified by clinical T stage, node positivity, and histology. There is 84.2% power to detect a 14.4% absolute increase in the primary endpoint of RFS from the ASSURE historical control of 55.8% to 70.2% at 5 yrs (HR 0.70). The study is also powered to detect a significant OS benefit (HR 0.67). Safety, feasibility, and quality of life are key secondary endpoints. PROSPER RCC exemplifies team science and incorporates a host of correlative work to examine the significance of the baseline immune milieu and changes induced by neoadjuvant priming and to identify predictive gene expression patterns. New collaborations welcomed. Clinical trial information: NCT03055013.

Heterogeneity in early oncologic outcomes among men with NCCN intermediate-risk prostate cancer treated with radical prostatectomy

144

Background: The National Comprehensive Cancer Network (NCCN) risk classification scheme for prostate cancer (PCa) encompasses several definitions and has been shown to contain significant heterogeneity. Because patients possessing a single intermediate-risk (IR) feature may be regarded as ineligible for active surveillance (AS), we aimed to compare pathologic and early oncologic outcomes between those with low-risk (LR) and IR features based on the number of criteria met. Methods: We queried the National Cancer Database (NCDB) to identify men with NCCN LR (cT1-T2a, prostate-specific antigen [PSA] < 10 ng/mL, and Gleason score (GS)≤6) and IR PCa diagnosed from 2010-2014 who were treated with radical prostatectomy (RP). Patients with IR PCa were stratified based on a single factor: clinical stage (cT2b-T2c), PSA (10-20 ng/mL), GS 3+4, or GS 4+3 alone. The pathologic outcomes including any Gleason upgrade, and adverse pathology (primary Gleason 4 or ≥pT3 at RP), and receipt of adjuvant radiation therapy (RT) were compared between the LR and IR groups. Odds ratios for pathologic outcomes and receipt of adjuvant RT were computed using logistic regression analyses. Results: Of 181,847 men treated with RP, we identified 30.7% and 37.1% with LR and IR PCa, respectively. Of 67,623 with IR PCa, 4,075 (6%) were due to clinical stage alone, 5,004 (7.4%) by PSA, 43,409 (64.2%) by GS 3+4, and 15,135 (22.4%) by GS 4+3. Patients meeting IR by clinical stage alone had similar risks of adverse pathology as LR patients (OR 1.03, 95%CI 0.94-1.13, p = 0.49). In contrast, those meeting IR by PSA alone had higher risks of adverse pathology compared with LR individuals (OR 2.20, 95%CI 2.05-2.36, p < 0.001). Moreover, receipt of adjuvant RT was similar among LR and IR patients by clinical stage alone (p = 0.62), and higher among patients meeting IR by PSA alone (OR 2.99, 95% CI 2.43-3.69, p < 0.001). Conclusions: Based on national cancer registry data, early outcomes among men meeting the NCCN IR definition for PCa are heterogeneous. IR patients by clinical stage alone had similar rates of adverse pathology as did LR group. Broadened eligibility for AS should be considered to include those meeting favorable IR definitions.

National determinants of active surveillance among patients with clinical stage 1A kidney tumors

694

Background: Active surveillance (AS) has been increasingly recognized as a viable management strategy for patients with small renal masses (SRM). To better understand the contemporary management landscape of SRMs we examined practice patterns in a nationally representative cancer database. Methods: We identified patients with clinical T1a renal masses within the National Cancer Database (NCDB) between 2010 to 2014. Patients were classified according to initial management received including AS, surgery, ablation, or other treatment. We characterized time trends in the use of surveillance versus definitive therapy and examined clinical and socio-demographic determinants of AS among patients with small renal masses using multivariate logistic regression models. Results: We identified 59,189 patients who satisfied the inclusion criteria. Of the total cohort, 1,733 (2.9%) individuals received initial management with AS, while 57,456 (97.1%) received definitive treatment. There was a slight increase in initial management with surveillance however rates remained less than 5% in all years. On multivariate analysis, patient age (OR: 1.08, 95% CI 1.08-1.09), treatment at an academic center vs. community center (OR: 2.05, 95% CI: 1.83-2.29), and African American vs. Caucasian race (OR: 1.56, 95% CI:1.35-1.80) were independently associated with use of active surveillance. Moreover, regional-level differences were observed with the highest utilization of AS in the West North Central census division. Conclusions: Based on cancer registry data, national utilization of AS for SRMs remains very low, and we observed clinical and facility-level differences. Further investigation is warranted to better understand the factors underlying management for patients with SRMs.

Induction of a BRCAness state by oncometabolites and exploitation by PARP inhibitors

11586

Background: 2-Hydroxyglutarate (2HG) exists as two enantiomers, R-2HG and S-2HG, and both are implicated in tumor progression via their inhibitory effects on α-ketoglutarate (aKG)-dependent dioxygenases. The former is an oncometabolite induced by isocitrate dehydrogenase-1 and -2 (IDH1/2) mutations, while the latter is produced under pathologic processes such as hypoxia. Recurring IDH1/2 mutations were first identified in gliomas and acute myeloid leukemia (AML). Methods: Our group recently reported that IDH1/2 mutations induce a homologous recombination (HR) defect which renders tumor cells exquisitely sensitive to Poly (ADP-Ribose) polymerase (PARP) inhibitors. Remarkably, this “BRCAness” phenotype can be completely reversed by mutant IDH1/2 inhibitors, and it can be entirely recapitulated by treatment with either 2HG enantiomer in cells with intact IDH1/2. We performed a comprehensive series of studies that directly implicate two aKG-dependent dioxygenases, KDM4A and KDM4B, as key mediators of the observed phenotype. Results: Using the methodology and preliminary data obtained above as a basis for further inquiry, here we have extended these findings to several related gene mutations, which similarly induce profound synthetic lethality with PARP inhibitors in these tumors, and our data suggest a similar mechanism of action via which HR is suppressed. Finally, we provide additional evidence that suppression of 2HG production with small molecule inhibitors of mutant IDH1/2 function does not lead to any detectable decreases in cell growth or viability in several unique models. Conclusions: Small molecule inhibition of oncogenic kinases is a pillar of precision medicine in modern oncology, and this approach has been extrapolated to treat IDH1/2-mutant and other oncometabolite-producing cancers with inhibitors blocking the neomorphic activity of the mutant proteins. The findings present here directly challenge this therapeutic strategy, and they instead provide a novel approach to treat these tumors with DNA repair inhibitors. Based on these findings, we are planning a multi-center Phase II trial testing the efficacy of olaparib for the treatment of recurrent IDH1/2-mutant tumors later this year.

A phase III randomized study comparing perioperative nivolumab vs. observation in patients with localized renal cell carcinoma undergoing nephrectomy (PROSPER RCC)

TPS4596

Background: The anti-PD-1 antibody nivolumab (nivo) improves overall survival (OS) in metastatic treatment refractory RCC and is generally tolerable. In 2017, there is no standard adjuvant therapy proven to increase OS over surgery alone in non-metastatic (M0) disease. Mouse solid tumor models have revealed an OS benefit with a short course of neoadjuvant PD-1 blockade compared to adjuvant therapy. Two ongoing phase 2 studies of perioperative nivo in RCC patients (pts) have shown preliminary feasibility and safety with no surgical delays or complications. The PROSPER RCC trial will examine if the addition of perioperative nivo to radical or partial nephrectomy can improve clinical outcomes in pts with locally advanced RCC. With the goal of increasing cure and recurrence-free survival (RFS) rates in M0 RCC, we propose a three-pronged, multidisciplinary approach of presurgical priming with nivo followed by resection and adjuvant PD-1 blockade. Methods: Tumorbiopsy prior to randomization is mandatory to ensure the correct diagnosis and will permit unparalleled correlative science in this global, randomized, unblinded, phase 3 National Clinical Trials Network study. 766 pts with clinical stage ≥T2 or any node positive M0 RCC of any histology will be enrolled. The study arm will receive nivo 240mg IV for 2 doses prior to surgery followed by nivo adjuvantly for 9 months (q2 wks x 3 mo followed by q4 wks x 6 mo). The control arm will undergo the current standard of care: surgical resection followed by observation. Pts are stratified by clinical T stage, node positivity, and histology. There is 84.2% power to detect a 14.4% absolute increase in the primary endpoint of RFS from the ASSURE historical control of 55.8% to 70.2% at 5 yrs (HR 0.70). The study is also powered to detect a significant OS benefit (HR 0.67). Key safety, feasibility, and quality of life endpoints are incorporated. PROSPER RCC exemplifies team science with a host of planned correlative work to investigate the significance of the baseline immune milieu and changes after neoadjuvant priming and to identify predictive gene expression patterns. Additional collaborations are welcomed.

A randomized, phase II efficacy assessment of multiple MET kinase inhibitors in metastatic papillary renal carcinoma (PRCC): SWOG S1500

TPS4599

Background: PRCC constitutes approximately 15% of RCC cases, and no standard of care exists for metastatic disease. Approved VEGF- and mTOR-directed therapies for clear cell RCC in metastatic PRCC (mPRCC) have generally been ineffective. Trials assessing sunitinib and everolimus in non-clear cell RCC show a numerical advantage in progression-free survival (PFS) with sunitinib therapy. Prospective studies evaluating sunitinib in mPRCC show a broad range of efficacy, with PFS ranging from 1.6-6.6 months. Another possible approach to treating mPRCC is to target the MET protooncogene, which is frequently altered across both type I and type II disease. SWOG 1500 is a randomized, phase II study which will compare sunitinib to three MET-directed therapies in pts with mPRCC. Methods: Eligible pts will have PRCC (type I, type II or NOS), Zubrod performance status 0-1, and measurable metastatic disease. Pts may have received up to 1 prior systemic therapy, with the exception of prior VEGF-directed treatments. Treated brain metastases are allowed. Tissue must be available for central pathologic review of papillary subtype. Pts will receive either oral sunitinib, cabozantinib, crizotinib or savolitinib in a 1:1:1:1 randomization, with stratification by (1) prior therapy (0 vs 1) and (2) PRCC subtype (type I vs type II vs NOS). The primary endpoint of the study is to compare PFS with sunitinib to PFS with MET-directed therapies. Secondary endpoints in the study include comparison of response rate, overall survival and safety profile. Translational aims of the study include correlation of clinical outcome with MET mutation, copy number and other markers of MET signaling. Radiographic assessment will be performed every 12 wks. Interim analyses are planned for each arm. A total of 275 pts will be enrolled, with 26 pts registered as of Jan 30, 2017. Clinical trial information: NCT02761057.

Whole-genome analysis of papillary kidney cancer finds significant noncoding alterations

To date, studies on papillary renal-cell carcinoma (pRCC) have largely focused on coding alterations in traditional drivers, particularly the tyrosine-kinase, Met. However, for a significant fraction of tumors, researchers have been unable to determine a clear molecular etiology. To address this, we perform the first whole-genome analysis of pRCC. Elaborating on previous results on MET, we find a germline SNP (rs11762213) in this gene predicting prognosis. Surprisingly, we detect no enrichment for small structural variants disrupting MET. Next, we scrutinize noncoding mutations, discovering potentially impactful ones associated with MET. Many of these are in an intron connected to a known, oncogenic alternative-splicing event; moreover, we find methylation dysregulation nearby, leading to a cryptic promoter activation. We also notice an elevation of mutations in the long noncoding RNA NEAT1, and these mutations are associated with increased expression and unfavorable outcome. Finally, to address the origin of pRCC heterogeneity, we carry out whole-genome analyses of mutational processes. First, we investigate genome-wide mutational patterns, finding they are governed mostly by methylation-associated C-to-T transitions. We also observe significantly more mutations in open chromatin and early-replicating regions in tumors with chromatin-modifier alterations. Finally, we reconstruct cancer-evolutionary trees, which have markedly different topologies and suggested evolutionary trajectories for the different subtypes of pRCC.

Renal cell carcinoma accounts for more than 90% of kidney cancers. Papillary renal cell carcinoma (pRCC) is the second most common subtype of renal cell carcinoma. Previous studies, focusing mostly on the protein-coding regions, have identified several key genomic alterations that are critical to cancer initiation and development. However, researchers cannot find any key mutation in a significant portion of pRCC. Therefore, we carry out the first whole-genome study of pRCC to discover triggering DNA changes explaining these cases. By looking at the entire genome, we find additional potentially impactful alterations both in and out of the protein-coding regions. These newly identified critical mutations from scrutinizing the entire genome help complete our understanding of pRCC genomes. Two alterations we find are associated with prognosis, which could aid clinical decisions. We are also able to unveil mutation patterns, signatures and tumor evolutionary structures, which reflect the mutagenesis processes and help understand how heterogeneity arises. Our study provides valuable additional information to facilitate better tumor subtyping, risk stratification and potentially clinical management.

The incidence of adverse pathologic characteristics in small renal masses as size increases

596

Background: The AUA guidelines include active surveillance (AS) as an option for patients with the cT1a renal mass (≤4 cm). We evaluate how increasing tumor size (≤4 cm) correlates to the incidence of adverse pathologic features (APF) found on nephrectomy. Methods: We queried a single institution database of nephrectomy specimens from subjects undergoing surgery for renal cell carcinoma (RCC). From a total of 898 consecutive cases, 389 patients had primary tumors that were ≤4 cm and N0, M0. All cases were centrally reviewed for the following adverse pathologic features: high nuclear grade (Fuhrman grade 3 or 4), lymphovascular invasion (LVI), histologic tumor necrosis, sarcomatoid features, rhabdoid features, papillary type II histology and advanced stage (≥pT3). Tumor size categories were compared in 1 cm increments. Relationships between the variables were analyzed by chi-square, Fisher’s exact, and ANOVA tests. Results: There was a significant increase in tumor grade (p=0.006) and stage (p=0.04) seen as size increased. APF were found in 157 (40.4%) of tumors ranging from 22.2% for tumors ≤1 cm to 50.8% of tumors >3 to ≤4. There was a significant increase in the presence of one or more of any APF as size increased (p=0.013). Conclusions: Tumors ≤4 cm that could be considered for AS still show frequent aggressive characteristics at nephrectomy. As over half of tumors 3-4 cm have APF, caution is advised when placing patients with larger tumors on AS. Renal tumor biopsy may identify several aggressive histologic characteristics and could be considered to aid the selection of patients considering AS. [Table: see text]

Genomic characterization of sarcomatoid transformation in clear cell renal cell carcinoma

509

Background: Sarcomatoid transformation in renal cell carcinoma (ccRCC) is one of the worst prognostic factors and outcome is extremely poor. We evaluate genetic alterations implicated in this process. Methods: Nephrectomy specimens from ccRCC with sarcomatoid transformation had DNA extracted from carcinoma, sarcomatoid, and normal kidney regions. Exome capture/Illumina sequencing was performed in 21 samples. Somatic mutation calling was accomplished by comparing sarcomatoid-normal and carcinoma-normal pairs. Results: Two tumors had evidence of hypermutation and a mutational signature consistent with mismatch repair deficiency. In the remaining tumors, 42.6% of somatic mutations were shared. Sarcomatoid regions had a greater mutation burden (p = 4.0x10-4). A low percentage (57.9%) of tumors had mutations in VHL. Mutations in ccRCC driver genes, including PBRM1, PTEN, SETD2, ARID1A, and BAP1, were common. All mutations in ARID1A and BAP1 were specific to sarcomatoid regions. A high percentage (31.5%) of TP53 mutations were observed, all specific to sarcomatoid regions and occurring with loss of heterozygosity. Lastly, mutations in genes not previously described in ccRCC were observed, most sarcomatoid-specific. These include genes implicated in cell adhesion, polarity, motility, and WNT signaling (FAT1, FAT2, FAT3, PTK7), retinoic acid-regulated cell differentiation (RQCD1, LRIF1), and ubiquitinated protein trafficking and cytokinesis (TSG101). Conclusions: Sarcomatoid transformation in ccRCC results from clonal divergence from a common somatic cell of origin. The sarcomatoid region has significantly greater mutational burden of known cancer driver genes. TP53 mutations occurred at a high frequency and were exclusive to the sarcomatoid region. Hypermutation is a unique characteristic observed in a subset of tumors. Additional cohorts and mechanistic studies are critical to elucidate the role of candidate driver alterations.

Prognostic Factors in Renal Cell Carcinoma

The identification of prognostic factors in patients with renal cell carcinoma (RCC) represents an area of increasing interest. The tumor, node, metastasis (TNM) staging system is currently the most extensively used tool for providing prognostic information for RCC. Data published in the last few years have led to significant controversies as to whether further revisions are needed in current staging systems and whether improvements can be made with the introduction of new, more accurate and predictive prognostic factors not currently included in traditional staging systems. While integrated staging systems have improved the staging of RCC, the recent discovery of molecular tumor markers is expected to revolutionize the staging of RCC in the future and lead to the development of new therapies based on molecular targeting. The aim of the current review is to highlight such controversies and provide an update on current staging modalities and prognostic factors for RCC.