Molecular stratification of high-grade unclassified renal cell carcinoma to improve prognostication and management strategy

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Background: Unclassified renal cell carcinoma (uRCC) constitutes a large portion of aggressive non-clear cell RCC with limited response to standard therapy. Clinicopathologic parameters or biomarkers to stratify this heterogeneous group of tumors are currently lacking. In a recently reported analysis of 62 high-grade primary uRCC [“discovery cohort (DC)”], we identified distinct molecular subsets. We aimed to validate this molecular schema in an independent clinical cohort and further delineate the clinicopathologic and molecular features that may refine prognostication and management. Methods: All cases was reviewed by experienced GU pathologists based on the current WHO criteria. Primary (n = 54) or metastatic (n = 21) tumor samples from 75 uRCC patients [“validation cohort (VC)”] were analyzed by a CLIA-approved targeted NGS platform for somatic alterations. 37 had germline testing results available. We performed integrative analysis of both VC and DC. Results: Somatic mutations found in VC were NF2 (24%), SETD2 (13%), SMARCB1 (9%), TP53 (9%), TSC1 (9%), FH (8%), TSC2 (5%), MTOR (5%), EP300 (5%), BAP1 (5%), PBRM1 (5%) and PIK3CA (5%), highly consistent with findings in DC. Germline alterations [ FH (11), SDHB (4), and SMARCB1 (1)] were detected in previously unsuspected patients. Integrative analysis supported the presence of NF2-loss (NF2), hyperactive mTOR-driven (MTOR), FH/SDH-deficient (FH/SDH), and chromatin/DNA damage response (Chrom/DDR) molecular subsets. Univariate analysis of combined DC and VC (n = 137, median f/u 26 mos, death 74%) showed a significantly higher risk associated with NF2 subset than the MTOR group (Table). Clonality analysis confirmed NF2 inactivating mutation as a main driver in the NF2 subset. Rare cases with alterations indicating sensitivity or resistance to immunotherapy were also identified. Conclusions: Molecular features of high-grade uRCC improve risk stratification and provide rationale for distinct management strategies. [Table: see text]

Plasma Glycosaminoglycans as Diagnostic and Prognostic Biomarkers in Surgically Treated Renal Cell Carcinoma

BACKGROUND

Plasma glycosaminoglycan (GAG) measurements, when aggregated into diagnostic scores, accurately distinguish metastatic clear-cell renal cell carcinoma (RCC) from healthy samples and correlate with prognosis. However, it is unknown if GAG scores can detect RCC in earlier stages or if they correlate with prognosis after surgery.

OBJECTIVE

To explore the sensitivity and specificity of plasma GAGs for detection of early-stage RCC and prediction of recurrence and death after RCC surgery.

DESIGN, SETTING, AND PARTICIPANTS

This was a retrospective case-control study consisting of a consecutive series of 175 RCC patients surgically treated between May 2011 and February 2014 and 19 healthy controls.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Plasma GAGs in preoperative and postoperative RCC and healthy samples were measured using capillary electrophoresis with laser-induced fluorescence in a single blinded laboratory. A discovery set was first analyzed to update the historical GAG score. The sensitivity of the new GAG score for RCC detection versus healthy subjects was validated using the remaining samples. The correlation of the new GAG score to histopathologic variables, overall survival, and recurrence-free survival was evaluated using nonparametric and log-rank tests and multivariable Cox regression analyses.

RESULTS AND LIMITATIONS

The RCC cohort included 94 stage I, 58 stage II-III, and 22 stage IV cases. In the first discovery set (n=67), the new GAG score distinguished RCC from healthy samples with an area under the receiver operating characteristic curve (AUC) of 0.999. In the validation set (n=108), the GAG score achieved an AUC of 0.991, with 93.5% sensitivity. GAG scores were elevated in RCC compared to healthy samples, irrespective of and uncorrelated to stage, grade, histology, age, or gender. The total chondroitin sulfate concentration was an independent prognostic factor for both overall and recurrence-free survival (hazard ratios 1.51 and 1.25) with high concordance when combined with variables available at pathologic diagnosis (C-index 0.926 and 0.849) or preoperatively (C-index 0.846 and 0.736). Limitations of the study include its retrospective nature and moderate variability in GAG laboratory measurements.

CONCLUSIONS

Plasma GAGs are highly sensitive diagnostic and prognostic biomarkers in surgically treated RCC independent of stage, grade, or histology. Prospective validation studies on GAG scores for early detection, prediction, and surveillance for RCC recurrence are thus warranted.

PATIENT SUMMARY

In this study, we examined if a new molecular blood test can detect renal cell carcinoma in the early stages and predict if the cancer might relapse after surgery. The trial is registered on ClinicalTrial.gov as NCT03471897.

Comparison of Postradical Cystectomy Ileus Rates Using GIA-80 Versus GIA-60 Intestinal Stapler Device

OBJECTIVE

To assess the impact on recovery of bowel function using an 80 mm versus 60 mm gastrointestinal anastomosis (GIA) stapler following radical cystectomy and urinary diversion (RC/UD) for bladder cancer.

METHODS

We identified 696 patients using a prospectively maintained RC/UD database from January 2006 to November 2010. Two nonrandomized consecutive cohorts were compared. Patients between January 2006- and December 2007 (n = 180) were treated using a 60 mm GIA stapler, and 331 patients between January 2008 and December 2010 were subject to an 80 mm GIA stapler. All patients were treated on the same standardized postoperative recovery pathway. After accounting for baseline patient and perioperative characteristics, using a multivariable logistic regression model, we directly compared rates of postoperative ileus using a standardized definition.

RESULTS

Of 511 evaluable patients, ileus was observed in 32% (57/180) for 60 mm GIA versus 33% (110/331) for the 80 mm GIA. Preoperative renal function, age, gender, body mass index, and type of diversion were comparable between cohorts. On multivariate analysis, stapler size was not significantly associated with the development of ileus (GIA-60 vs GIA-80: OR 1.11; 95% CI 0.75, 1.66; P = .6). Positive fluid balance was associated with an increased risk (P = .019) and female sex a decreased risk (P = .008) of developing ileus compared to patients with negative fluid balance.

CONCLUSION

The size of the intestinal bowel anastomosis (GIA 80 mm vs 60 mm) does not independently impact the time to bowel recovery following RC/UD.

The association of renal cell carcinoma with gastrointestinal stromal tumors

BACKGROUND AND OBJECTIVES

Prior small studies have reported a possible association between renal cell carcinoma (RCC) and gastrointestinal stromal tumors (GISTs). In the largest known series, our objective was to describe the prevalence of RCC among patients with GISTs over 26 years at Memorial Sloan Kettering Cancer Center (MSKCC).

METHODS

We retrospectively reviewed MSKCC's prospectively maintained sarcoma and RCC databases and identified all patients with both RCC and GIST between 1980 and 2016. Demographic and clinicopathological characteristics were obtained.

RESULTS

A total of 9/405 (2.2%) GIST patients were identified with RCC, with a mean follow-up of 9.2 (range 3.8-28.4) years. Five out of nine (55.6%) patients had RCC and GIST diagnosis within 6 months of each other. Mean RCC tumor size was 3.0 (range 1.8-8) cm and 8/9 (88.9%) patients were RCC stage 1. A total of 4/9 (44.4%) patients had papillary RCC (pRCC) histology, 5/9 (55.6%) had additional alternative malignancies, and 4/9 (44.4%) had primary small bowel GIST.

CONCLUSIONS

Our series suggests a possible association of RCC with GISTs. In addition, we found a high frequency of pRCC histology, alternative malignancies, and small bowel GISTs in co-occurring RCC-GIST patients. Further investigation to identify genetic mutations, in this population, would assist in surveillance and treatment.

Cystic Renal Cell Carcinoma: A Report on Outcomes of Surgery and Active Surveillance in Patients Retrospectively Identified on Pretreatment Imaging

PURPOSE

We evaluated the outcomes of surgical intervention and active surveillance in patients diagnosed with cystic renal cell carcinoma at our hypothesized radiological cutoff of greater than 50% cystic.

MATERIALS AND METHODS

We identified all 430 patients with a pathologically confirmed cystic renal mass that fit our criteria from 2000 to 2015. The 292 patients with a lack of computerized tomography, tumors less than 50% cystic on imaging, multifocal tumors and prior renal cell carcinoma were excluded from study. Patients were stratified into benign or malignant subgroups, and radiological, clinicopathological and oncologic features were determined. Univariate and multivariate associations between clinicoradiological parameters in each group were analyzed. We similarly reviewed the records of a separate cohort of patients treated with active surveillance for cystic renal cell carcinoma.

RESULTS

Of the 138 identified cases of cystic renal cell carcinoma 102 (73.9%) were renal cell carcinoma and 36 (26.1%) were benign masses. Of the tumors 77.5% were Fuhrman grade 1-2, 83.4% were stage pT2 or less and 65.9% showed clear cell histology. On univariate analysis male gender, a solid component and increasing Bosniak classification were significant for malignancy. In a separate cohort we identified 38 patients on active surveillance. The growth rate was 1.0 mm per year overall and 2.3 mm per year for the solid component. At a median followup of more than 4 years in all cohorts there was no evidence of recurrence or metastasis of cystic renal cell carcinoma.

CONCLUSIONS

Patients with unifocal cystic renal cell carcinoma evaluated using a standardized radiological threshold of greater than 50% cystic had an excellent prognosis on active surveillance and after surgical resection.

Sarcomatoid renal cell carcinoma: Does stage impact survival?

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Background: Sarcomatoid differentiation is associated with poor clinical outcomes and is present in approximately 4% of patients with renal cell carcinoma (sRCC). However, limited studies have evaluated the impact of sarcomatoid differentiation among patients, especially with lower stage pT1−2 disease. Methods: This study evaluated 3,850 patients with RCC who underwent partial or radical nephrectomy between 2000−2017. Patients were divided into four groups for analysis: pT1−2NxMx RCC without sarcomatoid features, pT1−2NxMx sRCC, pT3−4 RCC without sarcomatoid features and pT3−4 sRCC. Clinicopathological outcomes including sex, race, age, primary histology, lymph node involvement and margin status were compared between groups using Chi−squared and T-tests. Overall survival rates were analyzed by constructing Kaplan−Meier curves, p−values were calculated using log−rank tests and fitting Cox proportional hazards models for adjusted analyses. Results: Among 3,850 cases, 168 (4.4%) sRCC patients were identified. Of these, 33 (19.6%) were pT1−2. The mean overall follow up time was 59.9 months. When comparing CSS between groups, survival was poorer in patients with sarcomatoid features regardless of pT stage (p < 0.0001). Of note, CSS was worse in sRCC pT1−2 patients compared to non−sarcomatoid pT3−4 patients. Overall survival (OS) results were similar, with sarcomatoid tumors having worse estimates on survival analysis (p < 0.0001). Conclusions: Patients with pT1−2 sRCC demonstrated worse CSS when compared to pT1-2 and pT3−T4 RCC without sarcomatoid features, regardless of primary histology. Sarcomatoid differentiation in low−stage disease may be a marker of poor oncologic outcomes requiring more vigilant surveillance and possible inclusion in adjuvant therapy trials. Our next step, which is currently ongoing, is to pursue a multi−institutional collaborative effort and establish a larger cohort of sRCC for analysis.

Association of preoperative neutrophil-to-lymphocyte ratio with immune populations in the tumor microenvironment of patients with clear cell renal cell carcinoma

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Background: Currently, there are no blood biomarkers that reflect the composition of immune cells in the tumor microenvironment (TME) of patients with clear cell renal cell carcinoma (ccRCC). High pre-operative neutrophil-to-lymphocyte ratio (NLR) is associated with adverse oncologic outcomes in ccRCC. However, how NLR relates to the immune cell composition in the TME is not well understood. Methods: We performed flow cytometry on tumor and adjacent normal renal tissue from a prospective cohort of patients who underwent surgery from 6/2015-7/2017. Immune cell populations, as a percent of total CD45+, were compared to baseline age, sex, body mass index (BMI), SSIGN score, sarcomatoid differentiation, and AJCC stage (I-IV). NLR was calculated using pre-operative absolute neutrophil-to-lymphocyte counts and further categorized as inflamed if NLR was ≥ 3. Correlations between continuous variables were performed using Spearman’s rank correlation. Comparisons of means were made using the Wilcoxon signed-rank test. Results: Among 48 patients, 32 (71%) were male, median age was 59 (IQR 52-66), BMI of 38.5 (IQR 26-32.6), SSIGN score of 8 (IQR 5-12), 9 (20%) had sarcomatoid differentiation, and 20 (44%) had metastases at presentation. No correlations were found between age, BMI, and different immune cell populations or NLR. A higher ratio of tissue resident (CD8a+CD49a+CD103+) to circulating (CD8a+CD49a-CD103-) CD8+ T-cells in the TME was associated with increasing stage at presentation (p = 0.02). Inflamed patients had similar total CD45+, CD8+ T cell, CD4+ T cell, and macrophage immune infiltration. However, inflamed patients had a higher proportion of CD8+ Tres infiltration (p = 0.04) and a trend towards higher neutrophil infiltration (p = 0.15). Conclusions: A higher proportion of resident CD8+T-cells correlated with advanced disease at presentation. NLR may reflect a change in the type of CD8+T cell population found in the TME. This population of CD8+ T-cells, and NLR as a possible biomarker should be validated and further investigated in a larger cohort of patients. Funding: Ruth L. Kirschstein Research Service Award T32CA082088 (A.S., M.G.)

Characterizing recurrent and lethal small renal masses in clear cell renal cell carcinoma using recurrent somatic mutations

INTRODUCTION

Small renal masses (SRMs) with evidence of clear cell renal cell carcinoma (ccRCC) are understudied. Current algorithms for the management of SRMs include surgical resection, ablation, and active surveillance. We sought to identify genomic biomarkers that could potentially refine the management of ccRCC in SRMs, especially in patients being evaluated for active surveillance.

METHODS

We identified patients who had SRMs (4cm or less) at time of surgery, had sequencing performed on their primary tumor and had a diagnosis of ccRCC. Patients were selected from 3 publicly available cohorts, The Cancer Genome Atlas (n = 110), University of Tokyo (n = 37), The International Cancer Genome Consortium (n = 31), and from our own institutional prospective database (n = 25). Among this cohort we analyzed mutations present in at least 5% of tumors, assessing for the enrichment of mutations and progression-free survival using the composite endpoint of recurrence or death of disease. Analysis was adjusted for multiple testing. A Cox regression model was used to assess clinical variables with significant mutations.

RESULTS

In total, 203 patients were available for analysis. Median follow-up was 43.1 months among survivors. Mutations in VHL, PBRM1, SETD2, BAP1, KDM5C, and MTOR were present in more than 5% of tumors. Twenty-three patients (11.3%) had recurrence or died of their disease. Mutations in KDM5C were associated with inferior survival from either recurrence or death from disease, adjusted P 0.033.

CONCLUSIONS

We identified mutations in SRMs in ccRCC that are associated with recurrence and lethality. The strongest association was seen in those with KDM5C mutations. Use of these genomic biomarkers may improve stratification of patients with SRMs and for those who may be appropriate for active surveillance. Prospective evaluation of these markers is needed.

Immune cell phenotyping of clear cell renal cell carcinoma

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Background: Clear cell renal cell carcinoma (ccRCC) tumors develop mechanisms that impair function and/or prevent entry of the host infiltrating immune cells (immune exclusion) within the tumor microenvironment. The goal of immunotherapy is to overcome this immune resistance. We aim to characterize the T−cell populations in a cohort of largely untreated high risk patients with ccRCC. Methods: We prospectively collected ccRCC tumor and adjacent normal kidney (NK) from patients undergoing surgical resection at our institution from 6/2015-8/2016. Immune cell phenotyping was performed by immune cell staining of single cell suspensions. Analysis of immune cell populations were determined by CD45+ staining and corresponding proportions of different T−cell populations (CD3+, CD4+, CD4+Treg, and CD8+ T cells). Staining for CD4+Treg was not available for two patients. Student t−test was utilized to compare the immune populations between tumor and adjacent NK tissue. Analysis was also conducted by stratifying patients who presented with localized versus metastatic disease. Results: A total of 31 tumor and adjacent NK were analyzed. Median tumor pathological size was 8.5cm (2.9cm−18cm), 27(87%) had pT3a−pT3b and 13(42%) presented with metastatic disease. Overall 84% of tumors had higher immune infiltrate with an average ratio of four-fold increase compared to adjacent NK as determined by CD45+ cells. Intriguingly, the other 16% presented with metastatic (4) or rapidly metastatic disease (1). Orthogonal validation with inferred immune populations using RNAseq data from the The Cancer Genome Atlas (TCGA) demonstrated similar aggressive behavior in tumors with lower immune infiltrate compared to NK. Comparison of immune cell populations of tumor and NK tissue is shown in table 1. No specific T-cell subtype was associated with specific clinical outcomes in this cohort. Conclusions: Our data shows a general trend of immune infiltration in ccRCC when compared to adjacent NK with a diversity of T-cell subsets and possible evidence of immune exclusion. Further genomic characterization of these tumors is currently underway. [Table: see text]

Prognostic value of lymph node yield during nephroureterectomy for upper tract urothelial carcinoma

INTRODUCTION

Lymph node dissection (LND) performed during radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC) remains controversial and difficult to evaluate. The aim of this study was to investigate whether removal of more lymph nodes during RNU is safe and improves oncologic outcomes.

METHODS

We evaluated 422 patients who underwent RNU with concomitant LND for upper tract urothelial carcinoma between 1976 and 2015, assessing for an association between total nodes removed, recurrence-free survival, and cancer-specific survival using Cox proportional hazards models. We also investigated the relationship between nodal yield and perioperative metrics and intersurgeon variability using linear regression.

RESULTS

In our cohort of 442 patients, 239 developed recurrences and 94 patients died of disease. Median follow-up among survivors was 3.7 years (interquartile range: 1.2, 7.4). The median nodal yield was 9 (interquartile range: 4, 16). Among patients with node-positive disease (pN1), we observed a significant improvement in recurrence-free survival (hazard ratio = 0.84 per 5 nodes removed, P = 0.039) and a nonsignificant improvement in cancer-specific survival with an increase in the nodal yield (hazard ratio = 0.90 per 5 nodes removed, P = 0.2). There was no evidence of an association between node yield and operative time, estimated blood loss, or 30-day complications on multivariable analysis. There was significant heterogeneity among surgeons regarding the extent of LND (P<0.0001).

CONCLUSIONS

We found that a more extensive node dissection may improve oncologic outcomes in a subset of high-risk patients without significantly increasing operative time or serious complications. Additionally, we identified considerable intersurgeon heterogeneity regarding the extent of LND furthering the notion of surgeon variability as a nonstandardized factor.

Secondary pelvic congestion syndrome: description and radiographic diagnosis

INTRODUCTION

Pelvic congestion syndrome (PCS) is a complex condition of the pelvic venous system leading to nonspecific pelvic pain that was initially described in females alone. The underlying abnormalities, though diverse, all result in increased pressure in the left gonadal vein which is transmitted retrograde into the pelvic venous system. Our primary aim was to describe our findings of secondary PCS as a distinct entity from primary PCS in that it has an identifiable vascular etiology and is gender nonspecific. We also aimed to assess the adequacy of late-arterial phase CT urography (CTU) as the initial imaging modality in diagnosing and evaluating secondary PCS.

MATERIALS AND METHODS

We retrospectively reviewed 59 patients with PCS, 36 males and 23 females ages 24 to 63, from 2000-2011. To maximize opacification, CTU images were taken in the late-arterial phase with a 35-50 second delay after contrast administration.

RESULTS

Review of our cases revealed multiple etiologies for PCS, including: Nutcracker syndrome (19 cases), cirrhosis (17), retroaortic left renal vein (11), tumor thrombosis of the IVC (5), portal vein thrombosis (4), renal cell carcinoma with left renal vein thrombosis (2), and left kidney AVF (1). The most common symptom was unexplained chronic pelvic pain. The patients in our series had clearly identifiable vascular flow abnormalities leading to the development of PCS, and were therefore diagnosed as having secondary PCS. All cases were easily identified utilizing CTU to visualize and measure dilation of the left gonadal vein and pelvic varices. This modality also proved valuable in the identification and management of the various underlying causes of secondary PCS.

CONCLUSION

Secondary PCS is distinct from primary PCS in that it arises from clearly identifiable vascular flow abnormalities and occurs in both males and females. The diverse set of underlying etiologies, as well as the resulting congested varices, can be reliably and adequately visualized using CTU as the initial imaging modality.

Pad count is a poor measure of the severity of urinary incontinence

PURPOSE

We analyzed the correlation between pad use, as determined by objective pad count, and the severity of urinary incontinence, as measured by pad weight.

MATERIALS AND METHODS

We performed a retrospective study of consecutive incontinent patients who wore pads on a daily basis and were instructed to complete a 24-hour pad test. They were told to use the usual pads, change them as usual and place each in a separate plastic bag the day before the scheduled appointment. All pads were weighed and total urine loss was calculated by subtracting dry pad weight from wet pad weight, assuming that a 1 gm weight increase was equivalent to 1 ml of urine loss. The number of pads was correlated to pad weight using the Spearman rank correlation coefficient due to the nonparametric nature of the data.

RESULTS

The 116 patients included 51 men 39 to 89 years old (mean age 66) and 65 women 27 to 95 years old (mean age 72). When comparing the number of pads used to the gm of urine lost, the Spearman ρ was 0.26 (p=0.005) in the total cohort, and 0.40 and 0.26 (each p<0.05) in males and females, respectively.

CONCLUSIONS

There was little correlation between the number of pads used and the severity of urinary incontinence (r=0.26). These data suggest that pad count should not be used as an objective measure of incontinence severity. Instead, pad weight on a 24-hour pad test should be used.