Prognostic Value of Histologic Subtype and Treatment Modality for T1a Kidney Cancers

INTRODUCTION

To evaluate overall survival (OS) of T1a kidney cancers stratified by histologic subtype and curative treatment including partial nephrectomy (PN), percutaneous ablation (PA), and radical nephrectomy (RN).

MATERIALS AND METHODS

We queried the National Cancer Data Base (2004-2015) for patients with T1a kidney cancers who were treated surgically. OS was estimated by Kaplan-Meier curves based on histologic subtype and management. Cox proportional regression models were used to determine whether histologic subtypes and management procedure predicted OS.

RESULTS

46,014 T1a kidney cancers met inclusion criteria. Kaplan Meier curves demonstrated differences in OS by treatment for clear cell, papillary, chromophobe, and cystic histologic subtypes (all p < 0.001), but no differences for sarcomatoid (p = 0.110) or collecting duct (p = 0.392) were observed. Adjusted Cox regression showed worse OS for PA than PN among patients with clear cell (HR 1.58, 95%CI [1.44-1.73], papillary RCC (1.53 [1.34-1.75]), and chromophobe RCC (2.19 [1.64-2.91]). OS was worse for RN than PN for clear cell (HR 1.38 [1.28-1.50]) papillary (1.34 [1.16-1.56]) and chromophobe RCC (1.92 [1.43-2.58]). Predictive models using Cox proportional hazards incorporating histology and surgical procedure alone were limited (c-index 0.63) while adding demographics demonstrated fair predictive power for OS (c-index 0.73).

CONCLUSIONS

In patients with pathologic T1a RCC, patterns of OS differed by surgery and histologic subtype. Patients receiving PN appears to have better prognosis than both PA and RN. However, the incorporation of histologic subtype and treatment modality into a risk stratification model to predict OS had limited utility compared with variables representing competing risks.

A Systematic Review of Systemic Treatment Options for Advanced Non-Clear Cell Renal Cell Carcinoma

INTRODUCTION

There have been a number of recent advances in the management of advanced clear cell renal cell carcinoma (ccRCC). However, the majority of these studies excluded patients with non-clear cell RCC (nccRCC), and optimal management of nccRCC remains unknown.

MATERIALS AND METHODS

A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to evaluate systemic treatment options in locally advanced or metastatic nccRCC between 2000-2019. Randomized controlled trials, single-arm phase II-IV trials, and prospective analyses of medication access programs were included. The primary outcome measures were progression free survival (PFS), overall survival (OS), and objective response rate (ORR).

RESULTS

A total of 31 studies were included in the final analysis. There was the highest level of evidence to support first-line treatment of nccRCC with sunitinib. Additional single-arm trials support the use of other vascular endothelial growth factor (VEGF) inhibitors with axitinib and pazopanib, as well as mammalian target of rapamycin (mTOR) inhibition with temsirolimus or everolimus +/- bevacizumab. Immune checkpoint inhibition has an emerging role in nccRCC, but optimal sequencing of available options is not clear. Prospective data to support the use of newer immunotherapy combinations are lacking. Treatment for collecting duct carcinoma remains platinum-based chemotherapy.

CONCLUSIONS

The availability of randomized trials in nccRCC is limited, and most studies include outcomes for nccRCC as a group, making conclusions about efficacy by subtype difficult. This systematic review supports consensus guidelines recommending sunitinib or clinical trial enrollment as preferred first-line treatment options for nccRCC, but also suggests a more nuanced approach to management and new options for therapy such as immune checkpoint inhibition.

Pilot Study of [18F] Fluorodeoxyglucose Positron Emission Tomography (FDG-PET)/Magnetic Resonance Imaging (MRI) for Staging of Muscle-invasive Bladder Cancer (MIBC)

INTRODUCTION

Computed tomography (CT) has limited diagnostic accuracy for staging of muscle-invasive bladder cancer (MIBC). [¹⁸F] Fluorodeoxyglucose positron emission tomography (FDG-PET)/magnetic resonance imaging (MRI) is a novel imaging modality incorporating functional imaging with improved soft tissue characterization. This pilot study evaluated the use of preoperative FDG-PET/MRI for staging of MIBC.

PATIENTS AND METHODS

Twenty-one patients with MIBC with planned radical cystectomy were enrolled. Two teams of radiologists reviewed FDG-PET/MRI scans to determine: (1) presence of primary bladder tumor; and (2) lymph node involvement and distant metastases. FDG-PET/MRI was compared with cystectomy pathology and computed tomography (CT).

RESULTS

Eighteen patients were included in the final analysis, most (72.2%) of whom received neoadjuvant chemotherapy. Final pathology revealed 10 (56%) patients with muscle invasion and only 3 (17%) patients with lymph node involvement. Clustered analysis of FDG-PET/MRI radiology team reads revealed a sensitivity of 0.80 and a specificity of 0.56 for detection of the primary tumor with a sensitivity of 0 and a specificity of 1.00 for detection of lymph node involvement when compared with cystectomy pathology. CT imaging demonstrated similar rates in evaluation of the primary tumor (sensitivity, 0.91; specificity, 0.43) and lymph node involvement (sensitivity, 0; specificity, 0.93) when compared with pathology.

CONCLUSIONS

This pilot single-institution experience of FDG-PET/MRI for preoperative staging of MIBC performed similar to CT for the detection of the primary tumor; however, the determination of lymph node status was limited by few patients with true pathologic lymph node involvement. Further studies are needed to evaluate the potential role for FDG-PET/MRI in the staging of MIBC.

Predictive value of fibroblast growth factor receptor (FGFR) alterations on anti-PD-(L)1 treatment outcomes in patients (Pts) with advanced urothelial cancer (UC): Pooled analysis of real-world data

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Background: The tumor microenvironment in UC harboring FGFR gene alterations is characterized by decreased T-cell infiltration and low immune marker expression, potentially implicating suboptimal response to immune checkpoint inhibitors. The association between FGFR gene mutations/fusions and anti-PD-(L)1 treatment outcomes in advanced UC was assessed using real-world pt data. Methods: A pooled dataset of matched clinical and genomic data for advanced UC pts treated with anti-PD-(L)1 in any line from the Bladder Cancer Research Initiative for Drug Targets in Germany (BRIDGE) Consortium and UNC-CH was assessed. FGFR status was defined by a prespecified panel of FGFR2/3 mutations and fusions. Overall survival (OS) was analyzed using Kaplan-Meier estimates and Cox proportional hazards models. Multivariate analyses were performed using potential prognostic covariates (sex, age, baseline tumor stage, urothelial histology, smoking history, primary tumor location, and ECOG) in a Cox regression model for OS to assess their impact on the effect of FGFR alterations. Results: Median OS for FGFR+ pts (n=28) who received any line of anti-PD-(L)1 therapy was 9.5 mo vs 7.5 mo for FGFR− pts (n=139) (HR: 1.03, 95% CI: 0.60-1.76, p=0.93). Median OS for pts treated with first-line anti-PD-(L)1 was 5.42 mo in FGFR+ pts (n=10) and was not reached for FGFR− pts (n=31) (HR: 2.06, 95% CI: 0.68-6.24, p=0.19); median OS in second-line anti-PD-(L)1 was 6.5 mo (FGFR+; n=14) vs 5.7 mo (FGFR−; n=86) (HR: 0.89, 95% CI: 0.44-1.81, p=0.74). The multivariate analyses showed a significant trend of poorer OS in FGFR+ pts with first-line anti-PD-(L)1 (HR: 10.42, 95% CI: 1.45-74.97, p=0.02); wide CI may be attributed to small sample size for some categories in several covariates. Conclusions: Treatment with first-line anti-PD-(L)1 in FGFR+ pts may be associated with poorer OS outcomes in FGFR+ pts; however, this trend was not observed in FGFR+ pts treated with any line and second-line anti-PD-(L)1. Investigation of the predictive value of FGFR alterations to immunotherapy outcomes in larger real-world pt datasets is warranted.

Incidence and prediction of checkpoint inhibitor immune-related nephrotoxicity

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Background: Immune checkpoint inhibitors (ICIs), through inhibition of self-tolerance, have the potential to cause immune-related adverse events that can affect any organ, including the kidneys. Our study aimed to better characterize the incidence of and predictive characteristics for immune-related nephrotoxicity. Methods: All patients at the University of North Carolina (UNC) who received ICIs between April 2014 and December 2018 for any malignancy were identified. Patients on dialysis or those who received concurrent platinum-based chemotherapy were excluded. Any patient who subsequently had a clinically significant acute kidney injury (AKI), defined as a doubling or more of baseline creatinine, was included for analysis. A retrospective chart review was performed to determine the cause of AKI. Any uncertain cases were reviewed by two nephrologists for expert consensus (R.R. and V.D.). Results: 1766 patients received an ICI during the study period. 123 (7%) patients had AKI within one year of the first ICI dose. 14 were due to immune-related nephrotoxicity (11% of patients with AKI and 0.8% of all ICI patients). Pre-existing autoimmune disease was more likely in patients with immune-related nephrotoxicity than in those with non-immune AKI (14% vs 3%, p = 0.04). Similarly, concurrent or prior other immune-related adverse events were more common in patients with immune-related AKI (57% vs 6%, p = 0.01). Patients with immune-related AKI were more likely to see a nephrologist (57% vs 23%, p = 0.007) and had a more profound increase in creatinine from baseline (median 2.6 vs 1.6, p = 0.02). Age, sex, urinalysis findings, and primary tumor type were not associated with increased risk. Conclusions: The true incidence of ICI related nephrotoxicity is difficult to ascertain due to the many confounders that contribute to AKI in this population. Severe immune-related nephrotoxicity is rare, but patients with preexisting autoimmune disease or history of immune-related adverse events are at increased risk.

RNAseq and DNA whole-exome sequence analysis reveal novel response signatures to IO treatment in muscle invasive bladder cancer (MIBC) patients

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Background: Objective: To examine in a cohort of anti-PD-(L)1 immune checkpoint inhibitors (ICP) treated urothelial cancer patients a strategy combining treatment outcomes with molecular alterations, pathways, and immune/tumor microenvironment features to determine potential responder and rapid-progression signatures. Methods: De-identified clinical history and treatment outcomes were collected on 109 MIBC patients treated with ICP agents. Archived FFPE samples from these patients were obtained and processed for mRNAseq, exome-seq, tumor mutation burden (TMB), microsatellite instability (MSI) and mutation panel testing. Comprehensive tumor/immune profiling is being analyzed in the context of ICP treatments and RECIST 1.1 outcomes. A 60 gene MIBC 4-typer expression subtyper and other response associated predictors are used to stratify and identify positive/negative ICP response indicators. Results: 109 patients were identified (median age 75, 64% male, 78% white, 17% black). 74% of patients had received prior platinum-based chemotherapy, and 12% had received 2 or more prior lines of therapy. At initiation of ICP, 28% of patients had hemoglobin < 10, 30% had liver metastases, and 59% had ECOG performance status > 0. Mutation analysis of the first 66 patients showed TP53 (n = 34, 52%), FGFR (n = 17, 26%), CDKN2A (n = 13, 20%) and RB1 (n = 12, 18%) as the top alterations. No patients (0/8) with known pathogenic mutations in FGFR3 (S249C and TACC3-fusion) responded to ICP. Of patients with T2 staging prior to ICP (37/66), overall survival was markedly shorter (2.7 years) in those possessing FGFR3 mutations (n = 6/37) compared to that for FGFR3 WT patients (5.7 years, n = 31/37; p = 0.045). Further analyses of molecular features relative to treatment outcomes are ongoing to characterize response signatures. Conclusions: Our preliminary cohort of patients with pathogenic FGFR3 alterations showed 0% favorable response to ICP. We are expanding on this observation with further comprehensive molecular analyses and retrospective treatments/outcomes data. We anticipate identifying expression signatures that reflect ICP patient responder/non-responder signatures that may aid in future therapy decisions.

Pilot study of [18F] fluorodexoyglucose positron emission tomography-magnetic resonance imaging (FDG-PET-MRI) for staging of muscle-invasive bladder cancer

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Background: Standard of care imaging for staging MIBC is computed tomography (CT) abdomen and pelvis despite poor diagnostic accuracy. The addition of FDG-PET to evaluate biologic activity has been shown to improve detection of metastatic bladder cancer. Better soft tissue characterization with MRI may improve detection of local disease. We hypothesized that simultaneous acquisition of FDG-PET and MRI images (PET-MRI) would allow for more accurate preoperative staging in patients with MIBC. Methods: 21 patients with MIBC and planned radical cystectomy with lymph node dissection were enrolled. Four radiologists (2 senior, 2 junior) with expertise in MRI and PET independently reviewed MRI and FDG-PET scans, respectively, to determine: 1) extent of the primary bladder tumor; and 2) involvement of local lymph nodes and distant sites of disease. Combined radiologist reads were performed (senior MRI and junior PET and vice versa). Imaging results were compared to surgical pathology. Results: 18 patients were included in the final analysis (3 PET-MRI scans excluded due to technical pitfalls with image acquisition). Final pathology revealed 10 patients (56%) with muscle invasion and only 2 patients (11%) with lymph node involvement. Combined analyses of PET-MRI accurately detected the extent of the primary tumor (sensitivity 0.84, specificity 0.50, PPV 0.70, NPV 0.70), but was less accurate for the detection of lymph node involvement (sensitivity 0.00, specificity 1.00, no calculable PPV, NPV 0.91). Senior MRI radiologist had improved PPV and NPV for extent of primary tumor compared to junior MRI radiologist (PPV 0.71 vs 0.56, NPV 0.83 vs. 0.50), and senior PET radiologist had improved PPV with similar NPV for extent of primary tumor (PPV 1.00 vs 0.78, NPV 0.50 vs 0.55). No patient was determined to have distant metastatic disease. Conclusions: To our knowledge, this is the first study exploring the use of PET-MRI for staging MIBC. This novel imaging modality demonstrated promise in detecting the extent of the primary tumor. Further investigation of FDG-PET-MRI is needed to better determine its potential utility in staging MIBC.

Next-generation sequencing of primary prostate cancer tumors to reveal actionable opportunities for clinical management

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Background: The Strata Trial (NCT03061305) is a multi-institutional precision oncology collaboration structured as an observational protocol that aims to match patients to genomically guided therapies. Methods: Selected University of North Carolina (UNC) metastatic prostate cancer (mPC) patients were enrolled on this IRB-approved study. Formalin fixed paraffin-embedded primary tumor specimens, without matched germline controls, were sent for targeted next generation sequencing (NGS) to detect actionable variants, including: mutations in 87 genes, copy number variations in 31 genes, gene fusions in 46 gene drivers, and microsatellite instability (MSI) status. mPC-related genes of specific interest included: AR, ATM, BRCA1/2, ERG, MSH2, MSH6, PTEN, RB1, and TP53. Results: Of the 108 cases sequenced, 6 (6%) failed testing. Of the 102 mPC patients with sequence data, the median age was 69 (47-86), 60 (59%) were white, 35 (34%) were black, 1 (1%) was Asian, and 6 (6%) declined to identify race. NGS data revealed 122 variants in 27 genes: 73 patients (71%) had at least one variant. Among those 73 patients, 38 (52%) had only 1 variant, 24 (33%) had 2 variants, 8 (11%) had 3 variants, and 3 (4%) had 4 variants. TMPRSS2-ERG fusions occurred most frequently (51%), followed by TP53 variants (38%), and PTEN variants (16%). Only 8% of patients had variants in DNA damage repair genes, including ATM (3%), BRCA2 (3%) and MSH2 (2%). Two patients with MSI high tumors were treated with pembrolizumab, while 4 patients with deep BRCA2 or ATM deletions were eligible for trials of PARP inhibition. Conclusions: Our UNC experience shows that a high proportion of primary prostate cancer tumors from mPC patients have genomic variants, and two patients were treated based on these data. Limited actionability may reflect the landscape of currently FDA approved mPC treatments available clinical trials, or due to short duration of follow-up after enrollment on the Strata Trial.

Cabozantinib in advanced non-clear-cell renal cell carcinoma: a multicentre, retrospective, cohort study

BACKGROUND

Cabozantinib is approved for patients with metastatic renal cell carcinoma on the basis of studies done in clear-cell histology. The activity of cabozantinib in patients with non-clear-cell renal cell carcinoma is poorly characterised. We sought to analyse the antitumour activity and toxicity of cabozantinib in advanced non-clear-cell renal cell carcinoma.

METHODS

We did a multicentre, international, retrospective cohort study of patients with metastatic non-clear-cell renal cell carcinoma treated with oral cabozantinib during any treatment line at 22 centres: 21 in the USA and one in Belgium. Eligibility required patients with histologically confirmed non-clear-cell renal cell carcinoma who received cabozantinib for metastatic disease during any treatment line roughly between 2015 and 2018. Mixed tumours with a clear-cell histology component were excluded. No other restrictive inclusion criteria were applied. Data were obtained from retrospective chart review by investigators at each institution. Demographic, surgical, pathological, and systemic therapy data were captured with uniform database templates to ensure consistent data collection. The main objectives were to estimate the proportion of patients who achieved an objective response, time to treatment failure, and overall survival after treatment.

FINDINGS

Of 112 identified patients with non-clear-cell renal cell carcinoma treated at the participating centres, 66 (59%) had papillary histology, 17 (15%) had Xp11.2 translocation histology, 15 (13%) had unclassified histology, ten (9%) had chromophobe histology, and four (4%) had collecting duct histology. The proportion of patients who achieved an objective response across all histologies was 30 (27%, 95% CI 19-36) of 112 patients. At a median follow-up of 11 months (IQR 6-18), median time to treatment failure was 6·7 months (95% CI 5·5-8·6), median progression-free survival was 7·0 months (5·7-9·0), and median overall survival was 12·0 months (9·2-17·0). The most common adverse events of any grade were fatigue (58 [52%]), and diarrhoea (38 [34%]). The most common grade 3 events were skin toxicity (rash and palmar-plantar erythrodysesthesia; five [4%]) and hypertension (four [4%]). No treatment-related deaths were observed. Across 54 patients with available next-generation sequencing data, the most frequently altered somatic genes were CDKN2A (12 [22%]) and MET (11 [20%]) with responses seen irrespective of mutational status.

INTERPRETATION

While we await results from prospective studies, this real-world study provides evidence supporting the antitumour activity and safety of cabozantinib across non-clear-cell renal cell carcinomas. Continued support of international collaborations and prospective ongoing studies targeting non-clear-cell renal cell carcinoma subtypes and specific molecular alterations are warranted to improve outcomes across these rare diseases with few evidence-based treatment options.

FUNDING

None.

Next generation sequencing of primary prostate cancer tumors to reveal potentially actionable opportunities for clinical management: The UNC experience

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Background: The Strata trial (NCT03061305) is a multi-institutional precision oncology collaboration structured as an observational protocol that aims to match patients to genomically-guided therapies. Methods: Selected University of North Carolina (UNC) metastatic prostate cancer (mPC) patients were enrolled on this IRB-approved study. Formalin fixed paraffin-embedded primary tumor specimens, without matched germline controls, were sent for targeted next generation sequencing (NGS) to detect actionable variants, including: mutations in 87 genes, copy number variations in 31 genes, and gene fusions in 46 gene drivers. mPC-related genes of particular interest included: AR, ATM, BRCA1/2, ERG, MSH2, MSH6, PTEN, RB1, and TP53. Results: Of the 92 cases sequenced, 5 [5%] failed testing. Of the 87 mPC patients (median age 69 years [47-86]) enrolled: 53 [61%] were white, 28 [32%] were black, 1 [1%] was Asian, and 5 [6%] declined to be identified. NGS data revealed 106 variants in 27 genes: 62 patients (71%) had at least one variant, 21 (24%) had 2 variants, 7 (8%) had 3 variants, and 4 (3%) had 4 variants. Among the 62 patients with at least 1 identified variant, TMPRSS2-ERG fusion occurred most frequently (50%), followed by TP53 (40%), and PTEN (16%). 6% of all sequenced patients had variants in DNA damage repair genes including ATM (3%), BRCA2 (2%) and MSH2 (1%). One patient had a SLC45A3-ERG fusion combined with PTEN deep deletion, which has been associated with a more aggressive phenotype. One patient with a microsatellite-instability high tumor was treated with pembrolizumab. Conclusions: The UNC experience shows that a high proportion of primary prostate cancer tumors from mPC patients have genomic variants, and one patient was treated based on these data. Limited actionability may reflect the landscape of currently FDA approved mPC treatments, and available clinical trials. It may also be due to a short follow-up, and these data could inform treatment planning upon progression.

Fibroblast growth factor receptor status and response to immune checkpoint inhibition in metastatic urothelial cancer

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Background: Fibroblast growth factor receptor (FGFR) inhibitors are a promising new targeted therapy for patients with metastatic urothelial cancer (UC) and FGFR alterations. FGFR-altered tumors are more likely to be of the luminal molecular subtype, which is less immune infiltrated and may be less likely to respond to immune checkpoint inhibitors (ICP). Methods: Metastatic UC patients at the University of North Carolina who underwent targeted exon sequencing (any CLIA-certified platform) and were treated with ICP since 2014 were identified. Patients with any FGFR alteration were compared to patients without alterations (including mutations, fusions, and amplifications in FGFR1-4). Overall response rates (ORR) to ICP were assessed by a radiologist (K.M.) per RECIST 1.1 and compared between FGFR-altered and unaltered tumors using Fisher’s exact tests. Patients who died prior to radiologic assessment were considered non-responders. Results: 66 patients (median age 70, 65% male, 76% white, 21% black) were identified. Most patients (74%) had received prior platinum-based chemotherapy, and 13% had received 2 or more prior lines of therapy. At the time of initiation of ICP, 32% of patients had a hemoglobin < 10, 33% had liver metastases, and 72% had a performance status > 0. Fifteen (22%) patients had FGFR alterations. The ORR for all patients was 15%, with ORR of 13% in FGFR-altered patients compared with 16% in unaltered patients (p = 1.0). No patients (0/9, 0%) with known pathogenic mutations in FGFR3 responded to ICP compared to 10/57 (18%) of patients without these alterations (p = 0.33). 46% of FGFR-altered patients who stopped ICP due to progression received subsequent therapy. Conclusions: Response rates to ICP are low and there was no difference in ORR between FGFR-altered and unaltered patients. While no patient with pathogenic FGFR3 mutations responded to ICP in our cohort, this difference did not reach statistical significance. Given low response rates overall, some FGFR-altered patients may benefit from treatment with FGFR inhibitors prior to ICP. Analysis of larger cohorts of patients as well as patients from clinical trials and more in-depth molecular profiling may add further clarity.

Phase II trial of palbociclib in patients with metastatic urothelial cancer after failure of first-line chemotherapy

Background

The majority of urothelial cancers (UC) harbor alterations in retinoblastoma (Rb) pathway genes that can lead to loss of Rb tumour suppressor function. Palbociclib is an oral, selective inhibitor of CDK 4/6 that restores Rb function and promotes cell cycle arrest.

Methods

In this phase II trial, patients with metastatic platinum-refractory UC molecularly selected for p16 loss and intact Rb by tumour immunohistochemistry received palbociclib 125 mg p.o. daily for 21 days of a 28-day cycle. Primary endpoint was progression-free survival at 4 months (PFS4) using a Simon’s two-stage design. Next-generation sequencing including Rb pathway alterations was conducted.

Results

Twelve patients were enrolled and two patients (17%) achieved PFS4 with insufficient activity to advance to stage 2. No responses were seen. Median PFS was 1.9 months (95% CI 1.8–3.7 months) and median overall survival was 6.3 months (95% CI 2.2–12.6 months). Fifty-eight percent of patients had grade ≥3 hematologic toxicity. There were no CDKN2A alterations found and no correlation of Rb pathway alterations with clinical outcome.

Conclusions

Palbociclib did not demonstrate meaningful activity in selected patients with platinum-refractory metastatic UC. Further development of palbociclib should only be considered with improved integral biomarker selection or in rational combination with other therapies.

Multicenter Prospective Phase II Trial of Neoadjuvant Dose-Dense Gemcitabine Plus Cisplatin in Patients With Muscle-Invasive Bladder Cancer

Purpose Neoadjuvant chemotherapy followed by radical cystectomy (RC) is a standard of care for the management of muscle-invasive bladder cancer (MIBC). Dose-dense cisplatin-based regimens have yielded favorable outcomes compared with standard-dose chemotherapy, yet the optimal neoadjuvant regimen remains undefined. We assessed the efficacy and tolerability of six cycles of neoadjuvant dose-dense gemcitabine and cisplatin (ddGC) in patients with MIBC. Patients and Methods In this prospective, multicenter phase II study, patients received ddGC (gemcitabine 2,500 mg/m2 on day 1 and cisplatin 35 mg/m2 on days 1 and 2) every 2 weeks for 6 cycles followed by RC. The primary end point was pathologic downstaging to non-muscle-invasive disease (< pT2N0). Patients who did not undergo RC were deemed nonresponders. Pretreatment tumors underwent next-generation sequencing to identify predictors of chemosensitivity. Results Forty-nine patients were enrolled from three institutions. The primary end point was met, with 57% of 46 evaluable patients downstaged to < pT2N0. Pathologic response correlated with improved recurrence-free survival and overall survival. Nineteen patients (39%) required toxicity-related dose modifications. Sixty-seven percent of patients completed all six planned cycles. No patient failed to undergo RC as a result of chemotherapy-associated toxicities. The most frequent treatment-related toxicity was anemia (12%; grade 3). The presence of a presumed deleterious DNA damage response (DDR) gene alteration was associated with chemosensitivity (positive predictive value for < pT2N0 [89%]). No patient with a deleterious DDR gene alteration has experienced recurrence at a median follow-up of 2 years. Conclusion Six cycles of ddGC is an active, well-tolerated neoadjuvant regimen for the treatment of patients with MIBC. The presence of a putative deleterious DDR gene alteration in pretreatment tumor tissue strongly predicted for chemosensitivity, durable response, and superior long-term survival.

Advancements in optical techniques and imaging in the diagnosis and management of bladder cancer

Accurate detection and staging is critical to the appropriate management of urothelial cancer (UC). The use of advanced optical techniques during cystoscopy is becoming more widespread to prevent recurrent nonmuscle invasive bladder cancer. Standard of care for muscle-invasive UC includes the use of computed tomography and/or magnetic resonance imaging, but staging accuracy of these tests remains imperfect. Novel imaging modalities are being developed to improve current test performance. Positron emission tomography/computed tomography has a role in the initial evaluation of select patients with muscle-invasive bladder cancer and in disease recurrence in some cases. Several novel immuno-positron emission tomography tracers are currently in development to address the inadequacy of current imaging modalities for monitoring of tumor response to newer immune-based treatments. This review summaries the current standards and recent advances in optical techniques and imaging modalities in localized and metastatic UC.

Patterns of Bladder Preservation Therapy Utilization for Muscle-Invasive Bladder Cancer

Background: Trimodality bladder preservation therapy (BPT) in muscle invasive bladder cancer (MIBC) includes a maximal transurethral resection followed by concurrent chemoradiotherapy as an alternative to radical cystectomy (RC) in appropriately selected patients, or as a treatment option in non-cystectomy candidates. Several chemotherapy regimens can be used in BPT, but little is known about current practice patterns. Objective: To describe utilization patterns of BPT and associated survival outcomes in MIBC. Methods: Data were collected from the Retrospective International Study of Cancers of the Urothelial Tract (RISC), a database of 3,024 consecutive patients from 29 international academic centers from 2005 to 2013. Patients with clinical T2-T4aN0M0 urothelial cancer of the bladder were included. Results: 265 patients received BPT. Compared with the 1,447 patients who received RC, BPT patients were older, had poorer performance status, and had more comorbidities (p < 0.01 for all). Median overall survival (OS) was similar for patients treated with curative radiation doses in BPT and patients treated with RC (41 vs 46 months, p = 0.33, respectively). 45% of BPT patients received concurrent chemotherapy with radiation. The most common regimens included cisplatin alone (23%), carboplatin alone (22%), gemcitabine alone (10%), paclitaxel alone (9%), and 5-FU+mitomycin (5%). There were no significant differences in survival among chemotherapy regimens. Only 10 patients (4% of BPT patients) underwent salvage cystectomy. Conclusions: In clinical practice, BPT patients have similar survival to RC patients when treated with curative radiotherapy doses. Choice of concurrent chemotherapy regimen varied widely with no clear standard. Salvage cystectomy is rarely performed. Continued research is needed on the comparative effectiveness among BPT and RC, and among chemotherapy regimens in BPT.

Racial disparities in survival among patients with advanced renal cell carcinoma in the targeted therapy era

BACKGROUND

Historically, African American (AA) patients with renal cell carcinoma (RCC) have had inferior survival compared with Caucasian patients. Recent studies suggest that the survival disparity between races may be worsening since the advent of targeted therapies for RCC. In this study, survival rates among AA and Caucasian patients with advanced RCC are examined over time to determine whether a disparity in survival persists in the targeted therapy era.

METHODS

The authors identified patients with stage IV RCC in the National Cancer Data Base and compared survival between AA and Caucasian patients during the periods before (1998-2004) and after (2006-2011) the advent of targeted therapy.

RESULTS

In total, 48,846 patients were identified, and 10% were AA. Three-year survival among both AA and Caucasian patients improved between the 2 periods (P < .01 for both), with no interaction observed between race and improved survival over time (P = .15). The adjusted hazard ratio (HR) for death among AAs compared with Caucasians was 1.13 (95% confidence interval, 1.08-1.19) in the post-targeted therapy era, which was unchanged from the pretargeted therapy era (adjusted HR, 1.10; 95% confidence interval, 1.04-1.15). The adjusted HR was similar when the analysis was restricted to those who received systemic therapy.

CONCLUSIONS

Both AA and Caucasian patients with advanced RCC have had a significant improvement in survival since the advent of targeted therapy. However, AA patients maintain a survival disadvantage compared with Caucasians independent of treatment received, potentially related to unmeasured comorbidities, disease burden, or tumor biology. Cancer 2016;122:2988-2995. © 2016 American Cancer Society.

Sex disparities in use of chemotherapy and survival in patients with advanced bladder cancer

BACKGROUND

Women with advanced bladder cancer have inferior survival compared with men. However, women treated on clinical trials do not appear to have a survival disadvantage. Less frequent administration of systemic chemotherapy in women with advanced bladder cancer may contribute to their inferior survival.

METHODS

The authors identified patients diagnosed with stage IV bladder cancer from 1998 through 2010 using the National Cancer Data Base, a national outcomes database that includes 70% of all newly diagnosed cancer cases in the United States. Sex differences in demographics, systemic chemotherapy administration, and overall survival (OS) were compared.

RESULTS

A total of 23,981 patients were identified (35% of whom were female). Compared with men, women were older, more likely to be black, and less likely to be insured (P<.01 for all). The Charlson-Deyo comorbidity score did not differ between men and women. Women were less likely to receive systemic chemotherapy than men (45% vs 52%; adjusted relative risk, 0.91 [95% confidence interval (95% CI), 0.88-0.94]). Women had a lower median OS compared with men (8.0 months [95% CI, 7.7-8.3 months] vs 9.8 months [95% CI, 9.5-10.0 months]; P<.001). OS remained lower for women on multivariable analysis, even after adjusting for the administration of systemic chemotherapy (hazard ratio for death, 1.11 [95% CI, 1.08-1.15]).

CONCLUSIONS

Women are less likely than men to receive systemic chemotherapy for advanced bladder cancer and this difference may partially account for the poorer OS observed in women. However, OS remains lower in women independent of chemotherapy use, and may be related to unmeasured comorbidities, functional status, or tumor biology. Cancer 2016;122:2012-20. © 2016 American Cancer Society.

Intrinsic Genomic Differences Between African American and White Patients With Clear Cell Renal Cell Carcinoma

Importance

There are well-documented racial disparities in outcomes for African American patients with clear cell renal cell carcinoma (ccRCC). Despite a dramatic improvement in overall survival in white patients since the advent of targeted therapy, survival for African Americans with advanced ccRCC has not changed. There is little known about potential racial differences in tumor biology of ccRCC.

Objective

To determine if there are racial differences in the somatic mutation rate and gene expression of ccRCC tumors from white and African American patients.

Design, Setting, and Participants

Overall, 438 patients with ccRCC were identified through The Cancer Genome Atlas (TCGA) clear cell kidney (KIRC) dataset (419 white and 19 African American patients). The GSE25540 dataset containing 135 patients (125 white and 10 African American patients) was used for validation. Tumor samples were collected from numerous cancer centers and were examined for racial differences in somatic mutation rates and RNA expression. Racial differences in somatic mutation rates and RNA expression were examined.

Main Outcomes and Measures

The comparison of somatic mutation rates and differences in RNA expression in white and African American patients with ccRCC.

Results

Overall, 419 ccRCC tumor data sets from non-Hispanic white patients and 19 from non-Hispanic African American patients were identified through the publically available TCGA KIRC data set, and a validation set of 125 white and 10 African American ccRCC patient tumors was identified from the publicly available GSE25540 data set. African American patients were significantly less likely than white patients to have VHL mutations (2 of 12 [17%] vs 175 of 351 [50%], respectively; P = .04) and were enriched in the ccB molecular subtype (79% in African American vs 45% in white patients ; P = .005), a molecular subtype that carries a worse prognosis. It was found that RNA expression analysis revealed relative down-regulation of hypoxia-inducible factor (HIF) and vascular endothelial growth factor (VEGF)-associated pathways in African American patients compared with white patients.

Conclusions and Relevance

African American patients have less frequent VHL inactivation, are enriched in the ccB molecular subtype, and have decreased up-regulation of HIF-associated gene signatures than white patients. These genomic differences would predict decreased responsiveness to VEGF-targeted therapy and are a biologically plausible contributing factor to the worse survival of African American patients with ccRCC, even in the targeted therapy era.

Neoadjuvant chemotherapy administration and time to cystectomy for muscle-invasive bladder cancer: An evaluation of transitions between academic and community settings

OBJECTIVES

Neoadjuvant chemotherapy (NAC) before radical cystectomy is the standard of care for muscle-invasive bladder cancer (MIBC). Many patients are referred to an academic medical center (AMC) for cystectomy but receive NAC in the community setting. This study examines if administration of NAC in the community is associated with differences in type of NAC received, pathologic response rate (pT0), and time to cystectomy as compared to NAC administered at an AMC.

METHODS

We performed a retrospective study of patients with MIBC (cT2a-T4-Nx-M0) referred to a single AMC between 1/2012 and 1/2014 who received NAC. We analyzed chemotherapy received, time to cystectomy, pT0, and survival in patients who received NAC in our AMC compared to those treated in the community.

RESULTS

In all, 47 patients were analyzed. A similar total dose of cisplatin (median: 280 mg/m(2) for both groups, P = 0.82) and pT0 rate (25% vs. 29%, P = 0.72) were seen in patients treated in our AMC and the community. However, administration of NAC in the community was associated with a prolonged time to cystectomy compared with that in our AMC (median number of days 162 vs. 128, P<0.01). This remained significant after adjusting for stage, comorbidity status, and distance to the AMC (P = 0.02). Disease-free survival and overall survival did not differ.

CONCLUSION

Patients with MIBC treated with NAC in the community as compared to an AMC received similar chemotherapy and achieved comparable pT0 rates, indicating effective implementation of NAC in the community. However, NAC in the community was associated with longer time to cystectomy, suggesting a delay in the transition of care between settings.

Effect of sugars on the association between cowpea vicilin (7S storage proteins) and fungal cells

Vicilins (7S storage proteins) found in various legume seeds have been previously shown to interfere with the germination of spores or conidia of phytopathogenic fungi and inhibit yeast growth and glucose stimulated acidification of the medium by yeast cells. In the present work vicilins from cowpea (Vigna unguiculata) seeds were added to the growth medium of Saccharomyces cerevisiae cells and Fusarium oxysporum conidia. Helix pomatia lectin, wheat germ agglutinin and Ulex europaeus lectin were used to identify differences in the binding of the vicilins to the surface of cells of S. cerevisiae and F. oxysporum treated with this protein. After the growth period, the material in suspension (yeast cells) was centrifuged and the final pellet was also treated with different sugar (glucose, sucrose, glucosamine, N-acetyl-glucosamine) concentrations and 0.1 M HCl for extraction of vicilins associated to chitinous structures present in yeast cells. Our results showed that vicilin sub-units were present in the different sugar extracts of yeast cells pretreated with the vicilins and these proteins were eluted by 0.5 M solutions of sugars in the following order of efficiency of elution: N-acetyl-glucosamine, sucrose/glucose and glucosamine.

Legume vicilins (7S storage globulins) inhibit yeast growth and glucose stimulated acidification of the medium by yeast cells

Vicilin (7S storage proteins) isolated from different legume seeds were shown to inhibit yeast growth and glucose stimulated acidification of the medium by yeast cells. The degree of growth inhibition varied with the origin of vicilins. It was more than 90% for vicilins from cowpea (Vigna unguiculata, cultivar pitiuba) and equal to 65% for vicilins from Vigna radiata, in the case of Saccharomyces cerevisae. Vicilins from cowpea seeds inhibited the glucose stimulated acidification of the medium by S. cerevisae up to 60%. We have also observed that vicilins bind to yeast cells. We suggest that vicilins bind to chitin-containing structures of yeast cells and that such association could result in inhibition of H+ pumping, cell growth and spore formation. A final consequence of the yeast growth inhibition by vicilins is (probably) the formation of spores.

Electrical stimulation with Pt electrodes. VIII. Electrochemically safe charge injection limits with 0.2 ms pulses

The charge injection limits of a Pt electrode using 0.2 ms charge balanced, biphasic current pulses ranged from 50 to 150 microC/cm2 geometric if the potential excursions of the electrode are kept below those at which H2 or O2 is produced. These charge densities are three to ten times smaller than the currently accepted value based on earlier experiments in which the reversible surface reactions were fully utilized and the pulse widths were longer.