A contemporary comparison of laparoscopic versus open partial nephrectomy for renal cell carcinoma

PURPOSE

To analyze surgical and oncologic outcomes of patients undergoing open partial nephrectomy (OPN) versus laparoscopic partial nephrectomy (LPN) for treatment of renal cell carcinoma (RCC).

METHODS

We retrospectively investigated our institutional RCC database for patients who underwent PN for RCC from 1997 to 2018. Decision for technique was at the discretion of the operating urologist, following practice patterns and training history. Outcomes analyzed included pre/peri/post-operative parameters, pathologic outcomes, and disease recurrence rates.

RESULTS

1088 patients underwent PN from 1997 to 2018. After exclusionary criteria, 631 patients who underwent 647 unique PNs for a total of 162 OPN and 485 LPN remained. Baseline, pre-op, and pathologic characteristics were not statistically different. Surgical time was lower in laparoscopic cases [185 vs. 205 min] (p = 0.013). Margin involvement was not statistically different; LPN had lower estimated blood loss (EBL) [150 vs. 250 mL] (p < 0.001) and longer ischemia time [21 vs. 19 min] (p = 0.005). LPN had shorter length of stay [2 vs. 4 days] (p < 0.001), fewer overall complications (p < 0.001), and no significant difference in high-grade complications [2.89 vs. 4.32%] (p = 0.379). Fewer LPN patients developed metastases [1.65 vs. 4.94%] (p = 0.0499). Local recurrence rates were not statistically different [1.24 vs. 3.09%] (p = 0.193). Renal function was equivalent between cohorts post-operatively.

CONCLUSION

Long-term oncologic outcomes were not significantly different between LPN versus OPN, with no statistical difference in patient and tumor characteristics. LPN was associated with lower EBL, shorter length of stay, and lower overall complication risk. Renal function was not significantly different between cohorts.

Clinical significance of prostate cancer identified by transperineal standard template biopsy in men with nonsuspicious multiparametric magnetic resonance imaging

OBJECTIVE

Multiparametric magnetic resonance imaging (mpMRI) of the prostate has excellent sensitivity in detecting clinically significant prostate cancer (csCaP). However, whether a negative mpMRI in patients with a clinical suspicion of CaP can omit a confirmatory biopsy remains less understood and without consensus. Transperineal (TP) standard template biopsy (SBx) provides an effective approach to CaP detection. Our aim is to provide a comprehensive understanding of the CaP characteristics detected through TP SBx that are systematically overlooked by mpMRI.

METHODS

We conducted a retrospective analysis of all men who underwent prebiopsy mpMRI and subsequent a 20-core TP SBx at our hospital from September 2019 to February 2021. Patients with suspicious mpMRI received a combined TP SBx and targeted biopsy (TBx) (suspicious group), while those without suspicious (negative) mpMRI and who proceeded to biopsy, received TP SBx only (nonsuspicious group). A negative mpMRI was defined as the absence of suspicious findings and/or the presence of low-risk areas with a PI-RADS score of ≤2. Subsequently, we compared and evaluated the clinical and biopsy characteristics between these 2 groups.

RESULTS

We identified 301 men in suspicious group and 215 men in nonsuspicious group. The overall CaP detection rate and csCaP detection rate by TP SBx were 74.1%, 38.9% for suspicious group and 43.3%, 14.9% for nonsuspicious group, respectively. csCaP NPV of mpMRI was 85.1% with a csCaP prevalence 28.9%. The greatest percentage of cancer involvement (GPC) in biopsy core from nonsuspicious group was significantly lower than those of suspicious group (40% vs. 50%, p = 0.005), In multivariate logistic analysis, only PSAD > 0.15 ng/ml/cc was identified as an independent and significant predictor of csCaP in nonsuspicious group.

CONCLUSION

Within our cohort, false-negative rates of mpMRI for csCaP are substantial, reaching 15%. Nonsuspicious cases may contain a large volume tumor since the high GPC of SBx. For cases with nonsuspicious imaging and higher PSAD, a confirmatory biopsy may be necessary due to the increased risk of missed csCaP by mpMRI.

The effect of limited english proficiency on prostate-specific antigen screening in American men

PURPOSE

To evaluate how limited English proficiency (LEP) impacts the prevalence of prostate-specific antigen (PSA) screening in a contemporary, nationally representative cohort of men in the USA.

METHODS

The Medical Expenditure Panel Survey was utilized to identify the prevalence of PSA screening between 2013 and 2016 among men ≥ 55. Men who speak a language other than English at home were stratified by self-reported levels of English proficiency (men who speak English very well, well, not well, or not at all). Survey weights were applied, and groups were compared using the adjusted Wald test. A multivariable logistic regression model was used to identify predictors of PSA screening adjusting for patient-level covariates.

RESULTS

The cohort included 2,889 men, corresponding to a weighted estimate of 4,765,682 men. 79.6% of men who speak English very well reported receiving at least one lifetime PSA test versus 58.4% of men who do not speak English at all (p < 0.001). Men who reported not speaking English at all had significantly lower prevalence of PSA screening (aOR 0.56; 95% CI 0.35-0.91; p = 0.019). Other significant predictors of PSA screening included older age, income > 400% of the federal poverty level, insurance coverage, and healthcare utilization.

CONCLUSIONS

Limited English proficiency is associated with significantly lower prevalence of PSA screening among men in the USA. Interventions to mitigate disparities in prostate cancer outcomes should account for limited English proficiency among the barriers to guideline-concordant care.

Urinary volatile organic compounds in prostate cancer biopsy pathologic risk stratification using logistic regression and multivariate analysis models

Prostate cancer (PCa) is the second leading cause of cancer-related death in American men after lung cancer. The current PCa diagnostic method, the serum prostate-specific antigen (PSA) test, is not specific, thus, alternatives are needed to avoid unnecessary biopsies and over-diagnosis of clinically insignificant PCa. To explore the application of metabolomics in such effort, urine samples were collected from 386 male adults aged 44-93 years, including 247 patients with biopsy-proven PCa and 139 with biopsy-proven negative results. The PCa-positive group was further subdivided into two groups: low-grade (ISUP Grade Group = 1; n = 139) and intermediate/high-grade (ISUP Grade Group ≥ 2; n = 108). Volatile organic compounds (VOCs) in urine were extracted by stir bar sorptive extraction (SBSE) and analyzed using thermal desorption with gas chromatography and mass spectrometry (GC-MS). We used machine learning tools to develop and evaluate models for PCa diagnosis and prognosis. In total, 22,538 VOCs were identified in the urine samples. With regularized logistic regression, our model for PCa diagnosis yielded an area under the curve (AUC) of 0.99 and 0.88 for the training and testing sets respectively. Furthermore, the model for differentiating between low-grade and intermediate/high-grade PCa yielded an average AUC of 0.78 based on a repeated test-sample approach for cross-validation. These novel methods using urinary VOCs and logistic regression were developed to fill gaps in PCa screening and assessment of PCa grades prior to biopsy. Our study findings provide a promising alternative or adjunct to current PCa screening and diagnostic methods to better target patients for biopsy and mitigate the challenges associated with over-diagnosis and over-treatment of PCa.

First analysis of the safety and efficacy of UGN-101 in the treatment of ureteral tumors

OBJECTIVE

UGN-101 has been approved for the chemoablation of low-grade upper tract urothelial cancer (UTUC) involving the renal pelvis and calyces. Herein is the first reported cohort of patients with ureteral tumors treated with UGN-101.

PATIENTS AND METHODS

We performed a retrospective review of patients treated with UGN-101 for UTUC at 15 high-volume academic and community centers focusing on outcomes of patients treated for ureteral disease. Patients received UGN-101 with either adjuvant or chemo-ablative intent. Response rates are reported for patients receiving chemo-ablative intent. Adverse outcomes were characterized with a focus on the rate of ureteral stenosis.

RESULTS

In a cohort of 132 patients and 136 renal units, 47 cases had tumor involvement of the ureter, with 12 cases of ureteral tumor only (8.8%) and 35 cases of ureteral plus renal pelvic tumors (25.7%). Of the 23 patients with ureteral involvement who received UGN-101 induction with chemo-ablative intent, the complete response was 47.8%, which did not differ significantly from outcomes in patients without ureteral involvement. Fourteen patients (37.8%) with ureteral tumors had significant ureteral stenosis at first post-treatment evaluation, however, when excluding those with pre-existing hydronephrosis or ureteral stenosis, only 5.4% of patients developed new clinically significant stenosis.

CONCLUSIONS

UGN-101 appears to be safe and may have similar efficacy in treating low-grade urothelial carcinoma of the ureter as compared to renal pelvic tumors.

Genomic Tumor Correlates of Clinical Outcomes Following Organ-Sparing Chemoradiation Therapy for Bladder Cancer

PURPOSE

There is an urgent need for biomarkers of radiation response in organ-sparing therapies. Bladder preservation with trimodality therapy (TMT), consisting of transurethral tumor resection followed by chemoradiation, is an alternative to radical cystectomy for muscle-invasive bladder cancer (MIBC), but molecular determinants of response are poorly understood.

EXPERIMENTAL DESIGN

We characterized genomic and transcriptomic features correlated with long-term response in a single institution cohort of patients with MIBC homogeneously treated with TMT. Pretreatment tumors from 76 patients with MIBC underwent whole-exome sequencing; 67 underwent matched transcriptomic profiling. Molecular features were correlated with clinical outcomes including modified bladder-intact event-free survival (mBI-EFS), a composite endpoint that reflects long-term cancer control with bladder preservation.

RESULTS

With a median follow-up of 74.6 months in alive patients, 37 patients had favorable long-term response to TMT while 39 had unfavorable long-term response. Tumor mutational burden was not associated with outcomes after TMT. DNA damage response gene alterations were associated with improved locoregional control and mBI-EFS. Of these alterations, somatic ERCC2 mutations stood out as significantly associated with favorable long-term outcomes; patients with ERCC2 mutations had significantly improved mBI-EFS [HR, 0.15; 95% confidence interval (CI), 0.06-0.37; P = 0.030] and improved BI-EFS, an endpoint that includes all-cause mortality (HR, 0.33; 95% CI, 0.15-0.68; P = 0.044). ERCC2 mutant bladder cancer cell lines were significantly more sensitive to concurrent cisplatin and radiation treatment in vitro than isogenic ERCC2 wild-type cells.

CONCLUSIONS

Our data identify ERCC2 mutation as a candidate biomarker associated with sensitivity and long-term response to chemoradiation in MIBC. These findings warrant validation in independent cohorts.

Differentiation of patients with and without prostate cancer using urine 1 H NMR metabolomics

Prostate cancer (PCa) is one of the most prevalent cancers in men worldwide. For its detection, serum prostate-specific antigen (PSA) screening is commonly used, despite its lack of specificity, high false positive rate, and inability to discriminate indolent from aggressive PCa. Following increases in serum PSA levels, clinicians often conduct prostate biopsies with or without advanced imaging. Nuclear magnetic resonance (NMR)-based metabolomics has proven to be promising for advancing early-detection and elucidation of disease progression, through the discovery and characterization of novel biomarkers. This retrospective study of urine-NMR samples, from prostate biopsy patients with and without PCa, identified several metabolites involved in energy metabolism, amino acid metabolism, and the hippuric acid pathway. Of note, lactate and hippurate-key metabolites involved in cellular proliferation and microbiome effects, respectively-were significantly altered, unveiling widespread metabolomic modifications associated with PCa development. These findings support urine metabolomics profiling as a promising strategy to identify new clinical biomarkers for PCa detection and diagnosis.

The Risk of Catastrophic Healthcare Expenditures Among Prostate and Bladder Cancer Survivors in the United States

INTRODUCTION

Little is known about the rates of catastrophic health care expenditures among survivors of prostate and bladder cancer or the factors that place patients at highest risk for undue cost.

MATERIALS AND METHODS

The Medical Expenditure Panel Survey was utilized to identify prostate and bladder cancer survivors from 2011 to 2019. Rates of catastrophic health care expenditures (out-of-pocket health care spending >10% household income) were compared between cancer survivors and adults without cancer. A multivariable regression model was used to identify risk factors for catastrophic expenditures.

RESULTS

Among 2620 urologic cancer survivors, representative of 3,251,500 (95% CI 3,062,305-3,449,547) patients annually after application of survey weights, there were no significant differences in catastrophic expenditures among respondents with prostate cancer compared to adults without cancer. Respondents with bladder cancer had significantly greater rates of catastrophic expenditures (12.75%, 95% CI 9.36%-17.14% vs. 8.33%, 95% CI 7.66%-9.05%, P = .027). Significant predictors of catastrophic expenditures in bladder cancer survivors included older age, comorbidities, lower income, retirement, poor health status, and private insurance. Though White respondents with bladder cancer had no significantly increased risk of catastrophic expenditures, among Black respondents the risk of catastrophic expenditures increased from 5.14% (95% CI 3.95-6.33) without bladder cancer to 19.49% (95% CI 0.84-38.14) with bladder cancer (OR 6.41, 95% CI 1.28-32.01, P = .024).

CONCLUSIONS

Though limited by small sample size, these data suggest that bladder cancer survivorship is associated with catastrophic health care expenditures, particularly among Black cancer survivors. These findings should be taken as hypothesis-generating and warrant further investigation with larger sample sizes and, ideally, prospective investigation.

Estimated Prostate Volume by Semiautomatic Segmentation of MRI Is More Accurately Correlated with Radical Prostatectomy Specimen Weight than the Volume Calculated by Ellipsoid Formula

INTRODUCTION

Accurate in vivo prostate volume (PV) estimation is important for obtaining prostate-specific antigen density (PSAD) and further predicting clinically significant prostate cancer (csPCa). We aimed to evaluate the accuracy of multiparametric magnetic resonance imaging (mpMRI)-estimated PV compared to both volume and weight of radical prostatectomy (RP).

METHODS

We identified 310 PCa patients who underwent RP following combined targeted and systematic biopsy in our institution from September 2019 to February 2021. The MRI PV was determined using a semiautomated segmentation algorithm. RP PV was calculated using the prolate ellipsoid formula (length × width × height × π/6). Formula (prostate weight = [actual weight-3.8 g]/1.05 g/mL) was applied, and the resulting volume was used in further analysis.

RESULTS

The median PV from MRI, RP, and RP weight were 39 mL, 38 mL, and 44 mL, respectively. Spearman's rank correlation coefficients (ρ) were 0.841 (MRI PV vs. RP weight), 0.758 (RP PV vs. RP weight), and 0.707 (MRI PV vs. RP PV) (all p < 0.001). Decreased correlation between the MRI PV and RP PV was observed in the larger (more than 55 mL) prostate. The PSAD derived from MRI PV showed most efficient to detect csPCa in RP specimen (57.9% vs. 57.6% vs. 45.4%).

CONCLUSION

MRI PV is correlated better with RP weight than calculated RP PV, especially in larger prostate. The high csPCa detection rate in final pathology suggested that PSAD derived from MRI PV can be confidently used in clinical practice.

Characterization of the metabolomic profile of renal cell carcinoma by high resolution magic angle spinning proton magnetic resonance spectroscopy

BACKGROUND

Renal cell carcinoma (RCC) is a metabolic disease, with subtypes exhibiting aberrations in different metabolic pathways. Metabolomics may offer greater sensitivity for revealing disease biology. We investigated the metabolomic profile of RCC using high-resolution magic angle spinning (HRMAS) proton magnetic resonance spectroscopy (1HMRS).

METHODS

Surgical tissue samples were obtained from our frozen tissue bank, collected from radical or partial nephrectomy. Specimens were fresh-frozen, then stored at -80 °C until analysis. Tissue HRMAS-1HMRS was performed. A MatLab-based curve fitting program was used to process the spectra to produce relative intensities for 59 spectral regions of interest (ROIs). Comparisons of the metabolomic profiles of various RCC histologies and benign tumors, angiomyolipoma, and oncocytoma, were performed. False discovery rates (FDR) were used from the response screening to account for multiple testing; ROIs with FDR p < 0.05 were considered potential predictors of RCC. Wilcoxon rank sum test was used to compare median 1HMRS relative intensities for those metabolites that may differentiate between RCC and benign tumor. Logistic regression determined odds ratios for risk of malignancy based on the abundance of each metabolite.

RESULTS

Thirty-eight RCC (16 clear cell, 11 papillary, 11 chromophobe), 10 oncocytomas, 7 angiomyolipomas, and 13 adjacent normal tissue specimens (matched pairs) were analyzed. Candidate metabolites for predictors of malignancy based on FDR p-values include histidine, phenylalanine, phosphocholine, serine, phosphocreatine, creatine, glycerophosphocholine, valine, glycine, myo-inositol, scyllo-inositol, taurine, glutamine, spermine, acetoacetate, and lactate. Higher levels of spermine, histidine, and phenylalanine at 3.15 to 3.13 parts per million (ppm) were associated with decreased risk of RCC (OR 4 × 10-5, 95% CI 7.42 × 10-8, 0.02), while 2.84 to 2.82 ppm increased the risk of malignant pathology (OR 7158.67, 95% CI 6.3, 8.3 × 106). The specific metabolites characterizing this region remain to be identified. Tumor stage did not affect metabolomic profile of malignant tumors, suggesting that metabolites are dependent on histologic subtype.

CONCLUSIONS

HRMAS-1HMRS identified metabolites that may predict RCC. We demonstrated that those in the 3.14 to 3.13 ppm ROI were present in lower levels in RCC, while higher levels of metabolites in the 2.84 to 2.82 ppm ROI were associated with substantially increased risk of RCC. Further research in a larger population is required to validate these findings.

Route of Administration for UGN-101 and Impact on Oncological and Safety Outcomes

BACKGROUND

UGN-101 can be used for chemoablation of low-grade upper tract urothelial carcinoma (UTUC). The gel can be administered via a retrograde route through a ureteral catheter or an antegrade route via a nephrostomy tube.

OBJECTIVE

To report outcomes of UGN-101 by route of administration.

DESIGN, SETTING, AND PARTICIPANTS

We performed a retrospective review of 132 patients from 15 institutions who were treated with UGN-101 for low-grade UTUC via retrograde versus antegrade administration.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Survival outcomes are reported per patient. Treatment, complications, and recurrence outcomes are reported per renal unit. Statistical analysis was performed for primary endpoints of oncological response and ureteral stricture occurrence.

RESULTS AND LIMITATIONS

A total of 136 renal units were evaluated, comprising 78 retrograde and 58 antegrade instillations. Median follow-up was 7.4 mo. There were 120 cases (91%) of biopsy-proven low-grade UTUC. Tumors were in the renal pelvis alone in 89 cases (65%), in the ureter alone in 12 cases (9%), and in both in 35 cases (26%). Seventy-six patients (56%) had residual disease before UGN-101 treatment. Chemoablation with UGN-101 was used in 50/78 (64%) retrograde cases and 26/58 (45%) antegrade cases. A complete response according to inspection and cytology was achieved in 31 (48%) retrograde and 30 (60%) antegrade renal units (p = 0.1). Clavien grade 3 ureteral stricture occurred in 21 retrograde cases (32%) and only six (12%) antegrade cases (p < 0.01). Limitations include treatment bias, as patients in the antegrade group were more likely to undergo endoscopic mechanical ablation before UGN-101 instillation.

CONCLUSIONS

These preliminary results show a significantly lower rate of stricture occurrence with antegrade administration of UGN-101, with no apparent impact on oncological efficacy.

PATIENT SUMMARY

We compared results for two different delivery routes for the drug UGN-101 for treatment of cancer in the upper urinary tract. For the antegrade route, a tube is inserted through the skin into the kidney. For the retrograde route, a catheter is inserted past the bladder into the upper urinary tract. Our results show a lower rate of narrowing of the ureter (the tube draining urine from the kidney into the bladder) using the antegrade route, with no difference in cancer control.

Gadolinium-based Contrast Agent Biodistribution and Speciation in Rats

Background Gadolinium retention has been observed in organs of patients with normal renal function; however, the biodistribution and speciation of residual gadolinium is not well understood. Purpose To compare the pharmacokinetics, distribution, and speciation of four gadolinium-based contrast agents (GBCAs) in healthy rats using MRI, mass spectrometry, elemental imaging, and electron paramagnetic resonance (EPR) spectroscopy. Materials and Methods In this prospective animal study performed between November 2021 and September 2022, 32 rats received a dose of gadoterate, gadoteridol, gadobutrol, or gadobenate (2.0 mmol/kg) for 10 consecutive days. GBCA-naive rats were used as controls. Three-dimensional T1-weighted ultrashort echo time images and R2* maps of the kidneys were acquired at 3, 17, 34, and 52 days after injection. At 17 and 52 days after injection, gadolinium concentrations in 23 organ, tissue, and fluid specimens were measured with mass spectrometry; gadolinium distribution in the kidneys was evaluated using elemental imaging; and gadolinium speciation in the kidney cortex was assessed using EPR spectroscopy. Data were assessed with analysis of variance, Kruskal-Wallis test, analysis of response profiles, and Pearson correlation analysis. Results For all GBCAs, the kidney cortex exhibited higher gadolinium retention at 17 days after injection than all other specimens tested (mean range, 350-1720 nmol/g vs 0.40-401 nmol/g; P value range, .001-.70), with gadoteridol showing the lowest level of retention. Renal cortex R2* values correlated with gadolinium concentrations measured ex vivo (r = 0.95; P < .001), whereas no associations were found between T1-weighted signal intensity and ex vivo gadolinium concentration (r = 0.38; P = .10). EPR spectroscopy analysis of rat kidney cortex samples showed that all GBCAs were primarily intact at 52 days after injection. Conclusion Compared with other macrocyclic GBCAs, gadoteridol administration led to the lowest level of retention. The highest concentration of gadolinium was retained in the kidney cortex, but T1-weighted MRI was not sensitive for detecting residual gadolinium in this tissue. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Tweedle in this issue.

Development and Multicenter Case-Control Validation of Urinary Comprehensive Genomic Profiling for Urothelial Carcinoma Diagnosis, Surveillance, and Risk-Prediction

PURPOSE

Urinary comprehensive genomic profiling (uCGP) uses next-generation sequencing to identify mutations associated with urothelial carcinoma and has the potential to improve patient outcomes by noninvasively diagnosing disease, predicting grade and stage, and estimating recurrence risk.

EXPERIMENTAL DESIGN

This is a multicenter case-control study using banked urine specimens collected from patients undergoing initial diagnosis/hematuria workup or urothelial carcinoma surveillance. A total of 581 samples were analyzed by uCGP: 333 for disease classification and grading algorithm development, and 248 for blinded validation. uCGP testing was done using the UroAmp platform, which identifies five classes of mutation: single-nucleotide variants, copy-number variants, small insertion-deletions, copy-neutral loss of heterozygosity, and aneuploidy. UroAmp algorithms predicting urothelial carcinoma tumor presence, grade, and recurrence risk were compared with cytology, cystoscopy, and pathology.

RESULTS

uCGP algorithms had a validation sensitivity/specificity of 95%/90% for initial cancer diagnosis in patients with hematuria and demonstrated a negative predictive value (NPV) of 99%. A positive diagnostic likelihood ratio (DLR) of 9.2 and a negative DLR of 0.05 demonstrate the ability to risk-stratify patients presenting with hematuria. In surveillance patients, binary urothelial carcinoma classification demonstrated an NPV of 91%. uCGP recurrence-risk prediction significantly prognosticated future recurrence (hazard ratio, 6.2), whereas clinical risk factors did not. uCGP demonstrated positive predictive value (PPV) comparable with cytology (45% vs. 42%) with much higher sensitivity (79% vs. 25%). Finally, molecular grade predictions had a PPV of 88% and a specificity of 95%.

CONCLUSIONS

uCGP enables noninvasive, accurate urothelial carcinoma diagnosis and risk stratification in both hematuria and urothelial carcinoma surveillance patients.

Detection of extraprostatic extension by transperineal multiparametric magnetic resonance imaging-ultrasound fusion targeted combined with systemic template prostate biopsy

BACKGROUND

Extraprostatic extension (EPE) of prostate cancer (PCa) on transrectal (TR) needle core biopsy (Bx) is a rare histopathological finding that can help in clinical decision-making. The detection efficiency of the transperineal (TP) approach is yet to be explored.

METHODS

We retrospectively reviewed 2848 PCa cases using concomitant systemic template biopsy (SBx) and multiparametric magnetic resonance imaging (MRI)-ultrasound fusion-targeted biopsy (TBx) using the TR (n = 1917) or TP (n = 931) approach at our institution between January 2015 and July 2022. We assessed and compared clinical, MRI, and biopsy characteristics using different approaches (TP and TR) and methods (SBx and TBx).

RESULTS

In total, 40 EPE cases were identified (40/2848, 1.4%). TP showed a significantly higher EPE detection rate compared to TR in SBx (TR:0.7% vs. TP:1.6%; p = 0.028) and TBx (TR:0.5% vs. TP:1.2%; p = 0.033), as well as the combined methods (2.1% vs. 1.1%, p = 0.019). A significantly higher incidence of EPEs was found at non-base sites in TP than in TR (76.7% vs. 50%, p = 0.038). SBx showed a higher EPE detection rate than TBx; however, the difference was not statistically significant. TP showed higher prostate-specific antigen density (0.35 vs. 0.17, p = 0.005), higher frequency of GG4-5 in the cores with EPE (65.0% vs. 50.0%, p = 0.020), and more PCa-positive SBx cores (10 vs. 8, p = 0.023) compared to the TR.

CONCLUSIONS

TP may improve EPE detection compared with TR and should be applied to patients with adverse pre-biopsy features.

The ablative effect of mitomycin reverse thermal gel: Expanding the role for nephron preservation therapy in low grade upper tract urothelial carcinoma

PURPOSE

Assess the real-world ablative effect of mitomycin reverse thermal gel for low-grade upper tract urothelial carcinoma (UTUC) in patients who undergo biopsy only or partial ablation and evaluate utility of complete ablation prior to UGN-101.

MATERIAL AND METHODS

We retrospectively reviewed low-grade UTUC patients treated with UGN-101 from 15 high-volume centers. Patients were categorized based on initial endoscopic ablation (biopsy only, partial ablation, or complete ablation) and by size of remaining tumor (complete ablation, <1cm, 1-3cm, or >3cm) prior to UGN-101. The primary outcome was rendered disease free (RDF) rate at first post-UGN-101 ureteroscopy (URS), defined as complete response or partial response with minimal mechanical ablation to endoscopically clear the upper tract of visible disease.

RESULTS

One hundred and sixteen patients were included for analysis after excluding those with high-grade disease. At first post-UGN-101 URS, there were no differences in RDF rates between those who at initial URS (pre-UGN-101) had complete ablation (RDF 77.0%), partial ablation (RDF 55.9%) or biopsy only (RDF 66.7%) (P = 0.14). Similarly, a complimentary analysis focusing on tumor size (completely ablated, <1cm, 1-3cm or >3cm) prior to UGN-101 induction did not demonstrate significant differences in RDF rates (P = 0.17).

CONCLUSION

The results of the early real-world experience suggest that UGN-101 may play a role in initial chemo-ablative cytoreduction of larger volume low-grade tumors that may not initially appear to be amenable to renal preservation. Further studies will help to better quantify the chemo-ablative effect and to identify clinical factors for patient selection.

Impact of a negative confirmatory biopsy on risk of disease progression among men on active surveillance for prostate cancer

OBJECTIVE

Most prostate cancer active surveillance (AS) protocols suggest a confirmatory biopsy within 12 to 18 months of diagnosis to mitigate the risk of unsampled high-grade disease. We investigate whether the results of confirmatory biopsy impact AS outcomes and could be used to tailor surveillance intensity.

METHODS

We retrospectively reviewed our institutional database of prostate cancer patients managed by AS from 1997 to 2019 who underwent confirmatory biopsy and ≥3 biopsies overall. Biopsy progression was defined as either an increase in grade group or an increase in the proportion of positive biopsy cores to >34% and was compared between patients with a negative vs positive confirmatory biopsy using the Kaplan-Meier method and Cox proportional hazards regression.

RESULTS

We identified 452 patients meeting inclusion criteria for this analysis, of whom 169 (37%) had a negative confirmatory biopsy. With a median follow-up of 6.8 years, 37% of patients progressed to treatment, most commonly due to biopsy progression. A negative confirmatory biopsy was significantly associated with biopsy progression-free survival in multivariable analysis (HR 0.54, 95% CI 0.34-0.88, P = 0.013), adjusting for known clinical and pathologic factors, including use of mpMRI prior to confirmatory biopsy. Negative confirmatory biopsy was also associated with an increased risk of adverse pathologic features at prostatectomy but not with biochemical recurrence among men who ultimately underwent definitive treatment.

CONCLUSIONS

A negative confirmatory biopsy is associated with a lower risk of biopsy progression. While the increased risk of adverse pathology at time of definitive treatment sounds a small cautionary note regarding decreasing surveillance intensity, the majority of such patients have a favorable outcome on AS.

Radical cystectomy versus trimodality therapy for muscle-invasive bladder cancer: a multi-institutional propensity score matched and weighted analysis

BACKGROUND

Previous randomised controlled trials comparing bladder preservation with radical cystectomy for muscle-invasive bladder cancer closed due to insufficient accrual. Given that no further trials are foreseen, we aimed to use propensity scores to compare trimodality therapy (maximal transurethral resection of bladder tumour followed by concurrent chemoradiation) with radical cystectomy.

METHODS

This retrospective analysis included 722 patients with clinical stage T2-T4N0M0 muscle-invasive urothelial carcinoma of the bladder (440 underwent radical cystectomy, 282 received trimodality therapy) who would have been eligible for both approaches, treated at three university centres in the USA and Canada between Jan 1, 2005, and Dec 31, 2017. All patients had solitary tumours less than 7 cm, no or unilateral hydronephrosis, and no extensive or multifocal carcinoma in situ. The 440 cases of radical cystectomy represent 29% of all radical cystectomies performed during the study period at the contributing institutions. The primary endpoint was metastasis-free survival. Secondary endpoints included overall survival, cancer-specific survival, and disease-free survival. Differences in survival outcomes by treatment were analysed using propensity scores incorporated in propensity score matching (PSM) using logistic regression and 3:1 matching with replacement and inverse probability treatment weighting (IPTW).

FINDINGS

In the PSM analysis, the 3:1 matched cohort comprised 1119 patients (837 radical cystectomy, 282 trimodality therapy). After matching, age (71·4 years [IQR 66·0-77·1] for radical cystectomy vs 71·6 years [64·0-78·9] for trimodality therapy), sex (213 [25%] vs 68 [24%] female; 624 [75%] vs 214 [76%] male), cT2 stage (755 [90%] vs 255 [90%]), presence of hydronephrosis (97 [12%] vs 27 [10%]), and receipt of neoadjuvant or adjuvant chemotherapy (492 [59%] vs 159 [56%]) were similar between groups. Median follow-up was 4·38 years (IQR 1·6-6·7) versus 4·88 years (2·8-7·7), respectively. 5-year metastasis-free survival was 74% (95% CI 70-78) for radical cystectomy and 75% (70-80) for trimodality therapy with IPTW and 74% (70-77) and 74% (68-79) with PSM. There was no difference in metastasis-free survival either with IPTW (subdistribution hazard ratio [SHR] 0·89 [95% CI 0·67-1·20]; p=0·40) or PSM (SHR 0·93 [0·71-1·24]; p=0·64). 5-year cancer-specific survival for radical cystectomy versus trimodality therapy was 81% (95% CI 77-85) versus 84% (79-89) with IPTW and 83% (80-86) versus 85% (80-89) with PSM. 5-year disease-free survival was 73% (95% CI 69-77) versus 74% (69-79) with IPTW and 76% (72-80) versus 76% (71-81) with PSM. There were no differences in cancer-specific survival (IPTW: SHR 0·72 [95% CI 0·50-1·04]; p=0·071; PSM: SHR 0·73 [0·52-1·02]; p=0·057) and disease-free survival (IPTW: SHR 0·87 [0·65-1·16]; p=0·35; PSM: SHR 0·88 [0·67-1·16]; p=0·37) between radical cystectomy and trimodality therapy. Overall survival favoured trimodality therapy (IPTW: 66% [95% CI 61-71] vs 73% [68-78]; hazard ratio [HR] 0·70 [95% CI 0·53-0·92]; p=0·010; PSM: 72% [69-75] vs 77% [72-81]; HR 0·75 [0·58-0·97]; p=0·0078). Outcomes for radical cystectomy and trimodality therapy were not statistically different among centres for cancer-specific survival and metastasis-free survival (p=0·22-0·90). Salvage cystectomy was done in 38 (13%) trimodality therapy patients. Pathological stage in the 440 radical cystectomy patients was pT2 in 124 (28%), pT3-4 in 194 (44%), and 114 (26%) node positive. The median number of nodes removed was 39, the soft tissue positive margin rate was 1% (n=5), and the perioperative mortality rate was 2·5% (n=11).

INTERPRETATION

This multi-institutional study provides the best evidence to date showing similar oncological outcomes between radical cystectomy and trimodality therapy for select patients with muscle-invasive bladder cancer. These results support that trimodality therapy, in the setting of multidisciplinary shared decision making, should be offered to all suitable candidates with muscle-invasive bladder cancer and not only to patients with significant comorbidities for whom surgery is not an option.

FUNDING

Sinai Health Foundation, Princess Margaret Cancer Foundation, Massachusetts General Hospital.

Association of BCG Vaccine Treatment With Death and Dementia in Patients With Non-Muscle-Invasive Bladder Cancer

Importance

The BCG vaccine-used worldwide to prevent tuberculosis-confers multiple nonspecific beneficial effects, and intravesical BCG vaccine is currently the recommended treatment for non-muscle-invasive bladder cancer (NMIBC). Moreover, BCG vaccine has been hypothesized to reduce the risk of Alzheimer disease and related dementias (ADRD), but previous studies have been limited by sample size, study design, or analyses.

Objective

To evaluate whether intravesical BCG vaccine exposure is associated with a decreased incidence of ADRD in a cohort of patients with NMIBC while accounting for death as a competing event.

Design, Setting, and Participants

This cohort study was performed in patients aged 50 years or older initially diagnosed with NMIBC between May 28, 1987, and May 6, 2021, treated within the Mass General Brigham health care system. The study included a 15-year follow-up of individuals (BCG vaccine treated or controls) whose condition did not clinically progress to muscle-invasive cancer within 8 weeks and did not have an ADRD diagnosis within the first year after the NMIBC diagnosis. Data analysis was conducted from April 18, 2021, to March 28, 2023.

Main Outcomes and Measures

The main outcome was time to ADRD onset identified using diagnosis codes and medications. Cause-specific hazard ratios (HRs) were estimated using Cox proportional hazards regression after adjusting for confounders (age, sex, and Charlson Comorbidity Index) using inverse probability scores weighting.

Results

In this cohort study including 6467 individuals initially diagnosed with NMIBC between 1987 and 2021, 3388 patients underwent BCG vaccine treatment (mean [SD] age, 69.89 [9.28] years; 2605 [76.9%] men) and 3079 served as controls (mean [SD] age, 70.73 [10.00] years; 2176 [70.7%] men). Treatment with BCG vaccine was associated with a lower rate of ADRD (HR, 0.80; 95% CI, 0.69-0.99), with an even lower rate of ADRD in patients aged 70 years or older at the time of BCG vaccine treatment (HR, 0.74; 95% CI, 0.60-0.91). In competing risks analysis, BCG vaccine was associated with a lower risk of ADRD (5-year risk difference, -0.011; 95% CI, -0.019 to -0.003) and a decreased risk of death in patients without an earlier diagnosis of ADRD (5-year risk difference, -0.056; 95% CI, -0.075 to -0.037).

Conclusions and Relevance

In this study, BCG vaccine was associated with a significantly lower rate and risk of ADRD in a cohort of patients with bladder cancer when accounting for death as a competing event. However, the risk differences varied with time.

Designing a quality assurance process for quality control of nuclear magnetic resonance metabolomics studies of human blood

High-resolution magic angle spinning (HRMAS) nuclear magnetic resonance (NMR)-based metabolomics has demonstrated its utility in studies of biofluids for various diseases. HRMAS NMR spectroscopy is uniquely well suited for analyzing human blood samples because of the small quantity of samples and minimal preparation required. To develop this methodology into standardized clinical protocols, establishment of the method's quality assurance (QA) and evaluations of its quality control (QC) are critical. This study aims to assess the QA/QC measured from human blood specimens in the form of serum and plasma through within-subject and between-subject comparisons, as well as stability and consistency comparisons over several freezing-thawing cycles of sample storage conditions, and most importantly, the agreement of pooled control samples against individual samples.

Impact of an Expanded Definition of Family History on Outcomes of Active Surveillance for Prostate Cancer

PURPOSE

Despite family history being an established risk factor for prostate cancer, the role of a broader definition of family history inclusive of not just prostate cancer but other genetically related malignancies has not been investigated in the active surveillance population. Here, we evaluate the impact of an expanded definition of family history on active surveillance outcomes.

MATERIALS AND METHODS

Patients undergoing active surveillance for prostate cancer at Massachusetts General Hospital from 1997-2019 with detailed data available on family cancer history were identified. Primary outcome was biopsy progression-free survival, and secondary outcomes were treatment-free survival, adverse pathological features at prostatectomy, and biochemical recurrence after treatment. Statistical analyses were conducted using the Kaplan-Meier method and Cox regression.

RESULTS

Among 855 evaluable patients, 300 (35.1%) patients had any family history of prostate cancer, and 95 (11.1%) had a family history of related malignancies suggestive of a hereditary cancer syndrome (family history of hereditary cancer syndrome). Family history of prostate cancer alone was not associated with biopsy progression, whereas family history of hereditary cancer syndrome was associated with a significantly increased risk of biopsy progression (HR 1.43, 95%CI 1.01-2.02), independent of other known clinicopathological risk factors in multivariable analysis. Similarly, family history of hereditary cancer syndrome was associated with significantly lower treatment-free survival (HR 1.58, 95%CI 1.14-2.18) in multivariable analysis. No significant association was found between family history and adverse features on surgical pathology or biochemical recurrence.

CONCLUSIONS

An expanded family history suggestive of a hereditary cancer syndrome is an independent predictor of biopsy progression during active surveillance. Men with such a family history may still be offered active surveillance but should be counseled regarding the higher risk of disease progression.

Early experience with UGN-101 for the treatment of upper tract urothelial cancer - A multicenter evaluation of practice patterns and outcomes

BACKGROUND

UGN-101 is a novel delivery system for intracavitary treatment of upper tract urothelial cancer (UTUC). UGN-101 was approved based on a pivotal trial for small volume residual low-grade UTUC. Our aim was to report our experience with UGN-101 in a more heterogenous and real-world setting.

METHODS

We performed a retrospective review of all UGN-101 cases from 15 institutions with a focus on practice patterns, efficacy, and adverse effects. We include UGN-101 utilization in both the chemoablative and adjuvant setting.

RESULTS

There were a total 136 renal units treated from 132 patients. The majority of cases were biopsy proven low-grade UTUC. Practice patterns varied considerably - the most common administration technique was antegrade instillation via a percutaneous nephrostomy. When utilized in the adjuvant setting, 69% of patients were disease free at the time of their first endoscopic evaluation, while in the chemoablative setting, 37% were endoscopically clear on the first evaluation (P < 0.001). Complete response was higher in patients with smaller tumor size prior to UGN-101 induction; low volume (<1 cm) residual disease was associated with a 70% complete response, similar to disease free rate at first endoscopic evaluation when UGN-101 was used in the adjuvant setting. The use of maintenance doses of UGN-101 was reported in 27% of cases. The overall incidence of new onset, clinically significant ureteral stenosis was 23%.

CONCLUSIONS

This study represents the largest review of patients treated with UGN-101 and can serve as a basis of ongoing hypotheses regarding treatment with UGN-101 for UTUC.

Gleason Grade Group Concordance between Systematic Template Combining Magnetic Resonance Imaging Fusion Targeted Biopsy and Radical Prostatectomy Specimens: A Comparison of Transperineal and Transrectal Approaches

OBJECTIVE

To evaluate the Gleason grade (GG) discrepancy between biopsy (Bx) techniques (transperineal [TP] /transrectal [TR] approaches or multiparametric magnetic resonance imaging [mpMRI] targeted biopsy [TBx] / standard template biopsies [SBx]) and radical prostatectomy (RP) specimens.

PATIENTS AND METHODS

We identified 310 prostate cancer (PCa) patients who underwent RP following either TP TBx combining SBx (20-core) (n = 105) or TR TBx combining SBx (12-core) (n = 205) from September 2019 to February 2021. The Bx GG was based on the core with the highest GG and clinically significant PCa (csPCa) was defined as grade group 2 or greater prostate adenocarcinoma.

RESULTS

TP combined TBx and SBx (CBx) showed a better GG concordance (63.8% vs 57.1%) than the TR approach, but did not reach a statistical significance. TBx demonstrated a significantly higher csPCa detection than SBx in all patients including both approaches (70.2% vs 63.9%, P < .001). TR TBx showed a significantly higher concordance than TR SBx (52.2% vs 41.5%, P = .0.002) while TP TBx did not differ from TP SBx. TP CBx showed the highest Kappa coefficient (κ =0.48) followed by TR CBx (κ = 0.39). Thirty-eight of 69 (55.1%) cases with a GG1 diagnosis in CBx were upgraded to csPCa in RP. TR approach showed a trend of 2.8-fold risk to upgrade to RP csPCa than TP approach (P = .0.065).

CONCLUSION

The combination of SBx and TBx led to a better pathological concordance and lower upgrading rate for both TP and TR approaches to RP. With more SBx cores, TP CBx showed a better performance than TR CBx.

A machine learning approach to predict progression on active surveillance for prostate cancer

PURPOSE

Robust prediction of progression on active surveillance (AS) for prostate cancer can allow for risk-adapted protocols. To date, models predicting progression on AS have invariably used traditional statistical approaches. We sought to evaluate whether a machine learning (ML) approach could improve prediction of progression on AS.

PATIENTS AND METHODS

We performed a retrospective cohort study of patients diagnosed with very-low or low-risk prostate cancer between 1997 and 2016 and managed with AS at our institution. In the training set, we trained a traditional logistic regression (T-LR) classifier, and alternate ML classifiers (support vector machine, random forest, a fully connected artificial neural network, and ML-LR) to predict grade-progression. We evaluated model performance in the test set. The primary performance metric was the F1 score.

RESULTS

Our cohort included 790 patients. With a median follow-up of 6.29 years, 234 developed grade-progression. In descending order, the F1 scores were: support vector machine 0.586 (95% CI 0.579 - 0.591), ML-LR 0.522 (95% CI 0.513 - 0.526), artificial neural network 0.392 (95% CI 0.379 - 0.396), random forest 0.376 (95% CI 0.364 - 0.380), and T-LR 0.182 (95% CI 0.151 - 0.185). All alternate ML models had a significantly higher F1 score than the T-LR model (all p <0.001).

CONCLUSION

In our study, ML methods significantly outperformed T-LR in predicting progression on AS for prostate cancer. While our specific models require further validation, we anticipate that a ML approach will help produce robust prediction models that will facilitate individualized risk-stratification in prostate cancer AS.

Comprehensive genomic profiling of urine DNA for urothelial carcinoma detection and risk prediction

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Background: Clinical diagnosis and risk stratification of patients with urothelial carcinoma (UC) remains a challenge, with high rates of recurrence and disease progression following treatment. Urinary comprehensive genomic profiling (uCGP) has significant potential to aid in both diagnosis and prognostication of non-muscle-invasive and muscle-invasive disease. Methods: uCGP was performed on urine specimens collected at 9 centers across the US from 577 subjects prior to cystoscopy. 152 subjects were UC tumor positive (de novo and recurrence), 191 had a history of UC but negative by surveillance cystoscopy at time of collection, and 234 were urology control subjects undergoing cystoscopy without evidence of UC. Urine DNA was sequenced and comprehensively profiled across 60 genes for 6 classes of mutations using the CLIA-validated UroAmplitude test. Disease detection and molecular grade (high grade vs. low grade) algorithms were trained (n=345) and validated (n=232) in independent cohorts. Results: Among UC tumor positives, grade distribution was 53% high grade, 41% low grade, and 6% unknown. Stage distribution was Tis (5%), Ta (57%), T1 (16%), ≥T2 (15%), Tx (7%). 99% of tumor positive patients had one or more mutation identified. Interestingly, 69% of UC surveillance negative and 49% of urology controls also had at least one high impact mutation. The prevalence of mutations among controls necessitates machine learning algorithms to classify disease status. In validation, de novo tumor diagnosis demonstrated sensitivity of 93.8% and specificity of 89.4% and a NPV of 98.8% in urology controls. Recurrent tumors were detected with a PPV of 73.5%, sensitivity of 62.5% and specificity of 89.0% in patients with a history of UC. Molecular grading predicted high-grade with a PPV of 90.9% and a specificity of 96.7% compared to pathology. Urinary TP53 mutations were enriched in ≥T2 tumors relative to Ta (OR=14.8 [95%CI 4.6-47.5], P=0.00001). Copy number alterations were also associated with increased risk of muscle invasion, metastasis, and enriched for CIS relative to Ta tumors (≥T2: OR=6.4 [95%CI 1.8-22.9], P=0.019; CIS: OR=10.5 [95%CI 1.9-58.9], P=0.04). Conclusions: We developed and validated a uCGP test that provides robust noninvasive detection of UC across a diverse group of patients and clinical contexts, including non-muscle-invasive and muscle-invasive UC. Mutations with actionable or prognostic value are found in most subjects. These data suggest that uCGP classifies tumor presence with better performance than traditional urinary biomarkers. Importantly, uCGP identifies genomic markers of muscle invasion, metastasis, and CIS. With longer term follow-up, uCGP mutational profiles may reveal important prognostic information regarding risk of disease recurrence and progression. Additional studies are underway to further support the generalizability of these findings.

Multi-institutional matched comparison of radical cystectomy to trimodality therapy for muscle-invasive bladder cancer

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Background: Prior randomized controlled trials (RCT) comparing bladder preservation to radical cystectomy (RC) for muscle invasive bladder cancer (MIBC) closed early due to lack of accrual. Given that no future RCTs are foreseen, and in the absence of level 1 data, we aimed to provide the best evidence possible on outcomes of matched cohorts comparing trimodality therapy (TMT, maximal transurethral resection of bladder tumor followed by concurrent chemoradiation) to RC in order to guide management. Methods: This retrospective analysis included 703 patients with MIBC clinical stage T2-T3/4aN0M0 MIBC urothelial carcinoma of the bladder, 421 RC and 282 TMT who would have been eligible for both TMT or RC, treated at the Massachusetts General Hospital, Boston; Princess Margaret Cancer Centre, Toronto; and University of Southern California, Los Angeles between 2005-2017. To compare homogeneous cohorts, all patients included in this analysis had solitary tumors < 7 cm, no or unilateral hydronephrosis, and no multifocal carcinoma in situ. Treatment propensity scores were estimated using logistic regression, and patients were matched 3:1 with replacement. Covariates included age, sex, clinical T stage, hydronephrosis, (neo)adjuvant chemotherapy, body mass index, smoking history, and ECOG status. Overall survival (OS) was estimated with adjusted Cox models; cancer-specific survival (CSS), distant failure-free survival, pelvic nodal failure-free survival and metastasis-free survival (combined distant and pelvic nodal failure) were estimated with adjusted competing risk models. Our primary endpoint of interest was metastasis-free survival. The analysis was performed as intent-to-treat. Results: The 3:1 matched cohort comprised of 1,116 patients (834 RC vs 282 TMT). After matching, age (71.3 vs 71.6), cT2 clinical stage (88 vs 90%), presence of hydronephrosis (12 vs 10%), and use of (neo)adjuvant chemotherapy (60 vs 65%) were similar between RC and TMT cohorts. Salvage cystectomy was performed in 38 patients (13%) treated by TMT. At 5 years, metastasis-free (73 vs 78%, p = 0.07), distant failure-free (78 vs 82%, p = 0.14), and pelvic nodal failure-free (96 vs 94%, p = 0.33) survival were not statistically different between RC and TMT, whereas CSS and OS favored TMT (78 vs 85%, p = 0.02; 70 vs 78%, p < 0.001). Outcomes for RC and TMT were not different among centers. Final pT stage in the RC patients was: pT0 14%, pT1 7%, pT2 29%, pT3/4 42% and N+ 24%. Peri RC mortality was 2.1% and median number of nodes removed was 40. NMIBC recurrence occurred in 57/278 (20.5%) TMT patients. Conclusions: This large multi-institutional contemporary study provides the best evidence to date, in the absence of randomized trials, supporting TMT for select patients with MIBC. Oncologic outcomes seem to be equivalent between TMT and RC, affirming the position that TMT should be offered as an effective alternative.

Integrative clinical and molecular characterization of translocation renal cell carcinoma

Translocation renal cell carcinoma (tRCC) is a poorly characterized subtype of kidney cancer driven by MiT/TFE gene fusions. Here, we define the landmarks of tRCC through an integrative analysis of 152 patients with tRCC identified across genomic, clinical trial, and retrospective cohorts. Most tRCCs harbor few somatic alterations apart from MiT/TFE fusions and homozygous deletions at chromosome 9p21.3 (19.2% of cases). Transcriptionally, tRCCs display a heightened NRF2-driven antioxidant response that is associated with resistance to targeted therapies. Consistently, we find that outcomes for patients with tRCC treated with vascular endothelial growth factor receptor inhibitors (VEGFR-TKIs) are worse than those treated with immune checkpoint inhibitors (ICI). Using multiparametric immunofluorescence, we find that the tumors are infiltrated with CD8⁺ T cells, though the T cells harbor an exhaustion immunophenotype distinct from that of clear cell RCC. Our findings comprehensively define the clinical and molecular features of tRCC and may inspire new therapeutic hypotheses.

Predicting survival after radical prostatectomy: Variation of machine learning performance by race

BACKGROUND

Robust prediction of survival can facilitate clinical decision-making and patient counselling. Non-Caucasian males are underrepresented in most prostate cancer databases. We evaluated the variation in performance of a machine learning (ML) algorithm trained to predict survival after radical prostatectomy in race subgroups.

METHODS

We used the National Cancer Database (NCDB) to identify patients undergoing radical prostatectomy between 2004 and 2016. We grouped patients by race into Caucasian, African-American, or non-Caucasian, non-African-American (NCNAA) subgroups. We trained an Extreme Gradient Boosting (XGBoost) classifier to predict 5-year survival in different training samples: naturally race-imbalanced, race-specific, and synthetically race-balanced. We evaluated performance in the test sets.

RESULTS

A total of 68,630 patients met inclusion criteria. Of these, 57,635 (84%) were Caucasian, 8173 (12%) were African-American, and 2822 (4%) were NCNAA. For the classifier trained in the naturally race-imbalanced sample, the F1 scores were 0.514 (95% confidence interval: 0.513-0.511), 0.511 (0.511-0.512), 0.545 (0.541-0.548), and 0.378 (0.378-0.389) in the race-imbalanced, Caucasian, African-American, and NCNAA test samples, respectively. For all race subgroups, the F1 scores of classifiers trained in the race-specific or synthetically race-balanced samples demonstrated similar performance compared to training in the naturally race-imbalanced sample.

CONCLUSIONS

A ML algorithm trained using NCDB data to predict survival after radical prostatectomy demonstrates variation in performance by race, regardless of whether the algorithm is trained in a naturally race-imbalanced, race-specific, or synthetically race-balanced sample. These results emphasize the importance of thoroughly evaluating ML algorithms in race subgroups before clinical deployment to avoid potential disparities in care.

Combination MRI-targeted and systematic prostate biopsy may overestimate gleason grade on final surgical pathology and impact risk stratification

PURPOSE

Gleason grade (GG) on prostate biopsy is important for risk stratification and clinical decision making. Multiparametric MRI (mpMRI) improved detection of clinically significant disease and some studies suggest that MRI-fusion biopsy combined with systematic biopsy results in fewer upgrades on final surgical pathology. However, the downgrade rate is unclear and there is controversy in the literature. The objectives of this study are to assess the concordance of combination biopsy with final surgical pathology, and furthermore, to specifically determine downgrade rates.

MATERIALS AND METHODS

In our institutional mpMRI-ultrasound fusion biopsy database, 173 underwent targeted and systematic biopsy followed by radical prostatectomy (RP). GG on targeted, systematic and combination (targeted and systematic) biopsy were compared with GG on RP. Concordance rates between biopsy types were compared with the McNemar test. Proportion of GG upgrade or downgrade at the time of RP was also evaluated.

RESULTS

Surgical pathology was concordant with 44.5% of systematic biopsies, 46.8% of targeted biopsies, and 56.7% of combination biopsies. Combination biopsy significantly overestimated the final GG on RP compared to systematic biopsy (16.8% vs. 8.7% RR 1.93, 95% CI 1.36-2.75, P < 0.001). Downgrade rate from unfavorable to favorable intermediate-risk disease was 46.2%, and from high-risk to intermediate-risk disease was 45.1%.

CONCLUSIONS

Combination (targeted and systematic) biopsy is associated with the highest concordance rate between biopsy and RP pathology when compared with systematic or targeted biopsy alone. However, targeting MRI lesions and therefore the higher risk components, may at times overestimate the final surgical pathology which can result in overtreatment of what may truly be less aggressive disease.

Transperineal multiparametric magnetic resonance imaging-ultrasound fusion-targeted prostate biopsy combined with standard template improves perineural invasion detection

Perineural invasion (PNI) on biopsy is associated with adverse features in prostate cancer (PCa). Transrectal multiparametric magnetic resonance imaging (MRI)-targeted biopsy (TBx) has shown to detect higher presence of PNI than standard template biopsy (SBx). Transperineal biopsy provides effective cancer detection with lower complications than the transrectal approach. We compared PNI detection efficiency between SBx and TBx through transperineal approach. We identified patients with PCa who underwent transperineal TBx and concomitant standard 20-core template SBx from September 2019 to February 2021. Clinical, MRI imaging and biopsy characteristics were evaluated and compared between TBx and SBx. Two hundred thirty-eight patients with PCa underwent concomitant transperineal SBx and TBx procedures. Combined PNI+ (SBxPNI+ and/or TBxPNI+) was identified in 77 of 238 (32.4%) patients. SBx detected 23.9% PNI-positive patients and TBx detected 19.3% PNI-positive patients of all patients with PCa. Patients with PNI were with significantly different clinicopathological characteristics than patients without PNI. Although significantly more positive PCa cores and higher positive PCa core rate were found in the SBx method, patients with SBxPNI+ only shared similar features as TBxPNI+only patients. Of 176 cases with both SBxPCa and TBxPCa, TBx could detect 19 (15.1%) more PNI cases than SBx while SBx could detect 24 (18.3%) more PNI cases than TBx. Multiparametric MRI fusion-targeted biopsy in combination with template biopsy through transperineal approach achieved PNI detection rate over 30% of PCa cases. The increased PNI detection may improve the model to select active surveillance candidates in clinical practice.

To stage or not to stage: determining the true clinical significance of the biopsy tract through perinephric fat in assessing renal cell carcinoma

AIMS

Perinephric fat invasion (PFI) is a key component of renal cell carcinoma (RCC) staging, but there are limited data pertaining to biopsy tract seeding (BTS) resulting in perirenal tissue involvement [BTS with perinephric fat invasion (BTS-P)].The aim is to correlate clinical outcomes with pathologic stage to determine whether the presence of BTS-P should be considered a criterion to stage RCC as part of the pT3a category in the absence of any other upstaging variables.

MATERIALS AND RESULTS

We identified 304 renal biopsies from patients with subsequent nephrectomies for RCC; 33 of the tumours contained PFI. Each case was reviewed to determine the presence of BTS-P and other forms of invasion [e.g. non-BTS-P PFI, sinus fat invasion (SFI), and/or renal vein invasion (RVI)], and these findings were compared with survival outcomes. Ten (30%) of 33 tumours with PFI showed BTS-P as the only finding, and were otherwise pT1 tumours; six (60%) patients were alive without disease (AWOD) (mean, 77.5 months), three were lost to follow-up (LTF), and one died of other disease (DOOD). Two patients showed true PFI plus BTS-P; one was LTF and one is AWOD at 107 months. Ten (43%) of 23 patients with tumours with true invasion (PFI ± SFI and/or RVI) are AWOD (mean, 97.7 months), eight (35%) died of disease (DOD), four were LTF, and one DOOD. Kaplan-Meier survival curves showed that the cancer-specific survival was significantly worse in patients with true invasion (P = 0.044) than in those with BTS-P as the sole finding.

CONCLUSION

Patients with tumours showing BTS-P only appear to have better outcomes than those with other non-PFI invasion, suggesting that this finding should not be upstaged to pT3a. Additional studies are needed to corroborate the significance of our observations.

Conditional progression-free survival in men on active surveillance for prostate cancer stratified by NCCN risk

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Background: Active surveillance (AS) is an accepted management strategy for men with very low, low, and select cases of favorable intermediate National Comprehensive Cancer Network (NCCN) risk prostate cancer (PCa). However, how patients’ risk of disease progression evolves over time during AS has not been well defined. Conditional survival measures the probability a patient will continue to survive some number of years, given that they have already survived a certain number without progression. We evaluated our AS cohort to investigate overall and conditional progression free survival on AS, stratified by the NCCN risk groups. Methods: We reviewed our institutional database of 1254 men enrolled in AS for localized PCa from 1996-2016. Our AS protocol includes prostate specific antigen (PSA) and digital rectal exam (DRE) every 4-6 months for 3 years, then annually. Mandatory confirmatory 12 core biopsy is done at 12-18 months. Multiparametric magnetic resonance imagining (mpMRI) or additional systematic or MRI-fusion biopsies are done at the discretion of physician and patient. Overall freedom from pathologic grade progression on follow-up biopsy and treatment free survival were estimated using the Kaplan-Meier method. Survival curves were compared pairwise using the Log-rank test and adjusted for false discovery rates with the Benjamini-Hochberg procedure. Three-year conditional survival estimates were derived for both outcomes from the Kaplan-Meier estimator. Results: Of 1254 men, 521 (41.6%) met criteria for very low, 606 (48.4%) for low, and 125 (10.0%) for favorable intermediate NCCN risk at diagnosis. Median follow-up time was 6.5 years (IQR 4.1-9.4). Median pathologic grade progression free survival in years was significantly longer for very low risk (7.8, 95% CI 6.8-11.2) compared to low risk men (5.6, 95% CI 4.7-6.9), however neither was significantly different from favorable intermediate risk men (5.9). There was no significant difference in treatment free survival between the three risk groups. At diagnosis, the three-year risk for pathologic grade progression (24%, 95% CI 21-27%) and progression to treatment (22%, 95% CI 20-25%) were similar. However, with increasing time of event-free AS, the conditional probability of pathologic grade progression increased, while that of progression to treatment decreased. Conclusions: Our results demonstrate that despite a mild increase in pathologic progression free survival in very low risk men, there was no clear difference in overall treatment free survival between very low, low, and select favorable intermediate NCCN risk men. Further, with increased time spent on AS, despite elevated rates of pathologic progression, patient progression to treatment decreased. This trend may be indicative of changes in goals of care as men with PCa age and should be closely monitored during AS.

The impact of a positive family history on clinical and pathologic outcomes of active surveillance for prostate cancer

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Background: Active surveillance (AS) is the preferred management strategy for men with low-risk prostate cancer. However, approximately one in three men on AS experience progression of disease leading to treatment within 5 years, highlighting an urgent unmet need to reliably distinguish indolent from aggressive prostate cancer and improve patient selection criteria for AS. Germline genetic testing for DNA repair gene mutations is now recommended for patients with newly diagnosed prostate cancer and a strong family history of prostate cancer or BRCA1/2-related cancers, as such mutations have been associated with more aggressive forms of the disease. Here, we investigated the impact of family history on AS outcomes, under the hypothesis that men at high genetic risk for prostate cancer are at greater risk for progression to treatment on AS. Methods: We retrospectively reviewed detailed family history data of 958 patients from our institutional database of men enrolled in AS between 1997-2019. Data on family history of prostate cancer and hereditary cancer syndrome ( BRCA1/2-related prostate, breast, ovarian and/or pancreatic cancers) were collected and integrated into a composite family history score incorporating the number of relatives with each cancer weighted by degree of relatedness. A strong family history was defined as a composite score representing > 1 first-degree relative equivalent. The primary outcome was biopsy progression and secondary outcomes were adverse pathologic features at prostatectomy and biochemical recurrence. Statistical analysis was conducted using the Kaplan-Meier method and Cox proportional hazards regression. Results: In univariate analysis, a strong family history suggestive of a hereditary cancer syndrome (HR 1.37 [1.03-1.90], P = 0.033) was associated with a significant increased risk of biopsy progression; however, any family history of prostate cancer (HR 1.10 [0.89-1.35], P = 0.38) and a strong family history of prostate cancer (HR 1.35 [0.92-1.98], P = 0.13) were not significant. In multivariate analysis, a strong family history suggestive of a hereditary cancer syndrome remained a statistically significant predictor of biopsy progression (HR 1.42 [1.03-1.96], P = 0.03), after adjusting for age, percent core involvement on initial biopsy and PSA density. No significant association was found between family history and adverse features on surgical pathology or biochemical recurrence. Conclusions: A positive family history suggestive of a hereditary cancer syndrome is associated with an increased risk of biopsy progression on AS and is an independent predictor of biopsy progression. Men with such a family history may still be safely offered AS but should be counseled about the higher risk of progression. Further work to investigate the underlying genetic factors responsible for this increased risk is warranted.

Resolution of a High Grade and Metastatic BK Polyomavirus-Associated Urothelial Cell Carcinoma Following Radical Allograft Nephroureterectomy and Immune Checkpoint Treatment: A Case Report

BACKGROUND

BK viral infection in the posttransplant setting continues to cause serious morbidity with effects ranging from allograft nephropathy and dysfunction to urothelial malignancy.

RESULTS

In this report, we present a patient that developed BK-associated nephropathy and, 6 years later, locally advanced urothelial malignancy in the renal allograft with nodal, muscle, and extremity involvement. Following radical allograft nephroureterectomy, he was treated with palliative radiation and the immune checkpoint inhibitor atezolizumab. Follow-up imaging at 1 year demonstrated radiographic complete response.

CONCLUSIONS

This report supports the growing body of evidence supporting the association of urothelial malignancy and BK virus infection in renal transplant recipients. Further, it highlights the novel application of immune checkpoint inhibitors in the treatment of advanced posttransplant malignancy, in particular when the allograft is removed and the tumor is possibly of donor origin.

Viral integration in BK polyomavirus-associated urothelial carcinoma in renal transplant recipients: multistage carcinogenesis revealed by next-generation virome capture sequencing

BK polyomavirus (BKPyV)-associated cancer after transplantation has gained increasing attention. However, the role of BKPyV integration on oncogenesis is still unclear. In this study, next-generation virome capture sequencing of primary and metastatic tumors were performed in three patients with BKPyV-associated urothelial carcinoma after renal transplantation. As a result, a total of 332 viral integration sites were identified in the six tumors. Integration of BKPyV in both primary and metastatic tumors followed the mechanism of microhomology-mediated end joining mostly, since microhomologies between human and BKPyV genomes were significantly enriched in flanking regions of 84% of the integration sites. Viral DNA breakpoints were nonrandom and tended to assemble in large T gene, small T gene and viral protein 2 gene. There were three, one and one consensus integration sites between the primary and metastatic tumors, which affected LINC01924, eIF3c, and NEIL2 genes in the three cases respectively. Thus, we concluded that integration of BKPyV was a continuous process occurring in both primary and metastatic tumors, generating heterogenous tumor cell populations. Through this ongoing process, certain cell populations might have gained growth advantage or metastatic potential, as a result of viral integration either affecting the cellular genes where the viral DNA integrated to or altering the expression or function of the viral genes.

Renal biopsy cell cycle proliferation (CCP) score to predict adverse surgical pathology in renal cell carcinoma

747

Background: The role of renal mass biopsy (RMB) in risk stratifying patients with renal cell carcinoma (RCC) is unclear. We sought to determine whether the cell cycle proliferation (CCP) score from RMB can improve risk stratification of localized RCC. Methods: We identified patients with RCC who underwent RMB and subsequent partial/radical nephrectomy from 2000-2014. We used multivariable logistic regression to determine the association of patient-level variables and biopsy CCP score with adverse surgical pathology (Fuhrman grade 3-4, pT stage≥3, papillary type II histology, or evidence of metastasis at surgery). Effect size was estimated with odds ratios (OR) and discriminative performance with AUC. Results: Overall, 94 of 202 patients (46%) had adverse surgical pathology. On multivariable analysis, CCP score >0 was associated with 2.38-fold increased odds of adverse pathology (Table). Relative to the model omitting CCP score (AUC=0.70), the addition of CCP score as a continuous (AUC=0.731) or binary (AUC=0.730) variable yielded increased discriminative performance. Similar associations were observed in an analysis limited to patients with low-grade tumors on biopsy (bCCP: OR 2.44, p=0.024; cCCP: OR 1.57, p=0.11). In both models, increased lesion size on imaging was consistently associated with adverse pathology. Conclusions: Among patients with RCC, biopsy CCP score >0 was independently associated with adverse pathology, suggesting this classifier provides prognostic information beyond conventional pathologic data. Biopsy CCP score could be used to better guide patient-specific management.[Table: see text]

Detection of clinically significant prostate cancer after negative fusion and systematic biopsy

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Background: MRI/Ultrasound fusion biopsy of the prostate has enhanced the detection of clinically significant prostate cancer (csPCa). Detection of csPCa is greatest when fusion and systematic biopsies are combined. However, the finding of a negative fusion and negative systematic biopsy in patients with suspicious lesion on imaging raises the question of either falsely positive imaging or a false negative biopsy. Methods: We retrospectively reviewed our database of patients undergoing MRI/transrectal US-guided fusion biopsy. All images were graded according to the Prostate Imaging Reporting and Data System version (PIRADS) 2.0. Patients underwent targeted biopsy followed by systematic 12-core double sextant biopsy within the same session. csPCa was defined as Grade Group (GG) ≥2 PCa. Patients with no prostate cancer (PCa) found on biopsies were followed. MRI studies with PIRADS v2 score ≤ 2 were considered to have no MRI evidence of PCa. Results: A total of 400 patients had at least one PIRADS ≥3 lesion and underwent fusion/systematic biopsy. Of these, 113 (28.3%) patients had no evidence of PCa on either fusion or systematic biopsy. Median follow-up was 32.5 months. 44 (39%) patients underwent repeat MRI and of these, 24 (54%) had no evidence of PCa on repeat MRI. PIRADS lesion disappearance was associated with lower PSA Density (PSAd) (0.12 vs 0.20; P = 0.0319) and decreased progression to repeat biopsy (8.33% vs 95%; P < 0.0001). Patients who had a repeat biopsy had a greater PSAd ( 0.21 vs 0.12; P = 0.0054). Of 113 patients with negative initial biopsy, 23 (20.4 %) underwent repeat biopsy: 16 (14.2 %) had PCa and 11 (9.7%) had csPCa. Thus, 48% of patients who underwent repeat biopsy had csPCa. Among patients with a PCa on repeat biopsy, cancer was sampled by MRI targeted cores in 80% of patients. Conclusions: Despite a negative initial fusion/systematic biopsy, at least 10% of patients were subsequently diagnosed with clinically significant PCa. The combination of elevated PSAd and the persistence of a suspicious lesion on repeat MRI appears selective for previously missed PCa. However, after negative fusion biopsy, repeat MRI yields a high rate of PIRADS lesion disappearance in patients with low PSAd.

Using high-resolution magic angle spinning magnetic resonance spectroscopy to characterize the metabolomic profile of renal cell carcinoma

710

Background: Renal cell carcinoma (RCC) is a metabolic disease, with the various subtypes exhibiting aberrations in different metabolic pathways. Metabolomics may offer greater sensitivity for revealing disease biology than evaluation of tissue morphology. In this study, we investigate the metabolomic profile of RCC using high resolution magic angle spinning (HRMAS) magnetic resonance spectroscopy (MRS). Methods: Tissue samples were obtained from radical or partial nephrectomy specimens that were fresh frozen & stored at -80ºC. Tissue HRMAS MRS was performed by a Bruker AVANCE spectrometer. Metabolomic profiles of RCC & adjacent benign renal tissue were compared, and false discovery rates (FDR) were used to account for multiple testing. Regions of interest (ROI) with FDR < 0.05 were selected as potential predictors of malignancy. The Wilcoxon rank sum test was used to compare median MRS relative intensities for the candidate predictors. Logistic regression was used to determine odds ratios for risk of malignancy based on abundance of each metabolite. Results: There were 38 RCC (16 clear cell, 11 papillary, 11 chromophobe) & 13 adjacent normal tissue specimens (matched pairs). Metabolic predictors of malignancy based on FDR include histidine, phenylalanine, phosphocholine, serine, phosphocreatine, creatine, glycerophosphocholine, valine, glycine, myo-inositol, scylla-inositol, taurine, glutamine, spermine, acetoacetate & lactate. Higher levels of spermine, histidine & phenylalanine at 3.15-3.13 ppm were associated with a decreased risk of RCC (OR 4x10−5, 95% CI 7.42x10−8, 0.02), while 2.84-2.82 ppm increased the risk of malignant pathology (OR 7158.67, 95% CI 6.3, 8.3x106), and the specific metabolites characterizing this region remain to be identified. Tumor stage did not appear to affect the metabolomics of malignant tumors, suggesting that metabolites are more dependent on histologic subtype. Conclusions: HRMAS-MRS identified many metabolites that may predict RCC. We demonstrated that those in the 3.14-3.13 ppm ROI were present in lower levels in RCC, while higher levels of metabolites in the 2.84-2.82 ppm ROI substantially increased the risk of RCC.

Using high-resolution magic angle spinning magnetic resonance spectroscopy to characterize the metabolomic profile of fat-poor angiomyolipoma and renal cell carcinoma

711

Background: Fat-poor angiomyolipoma (AML) can be difficult to differentiate from renal cell carcinoma (RCC) radiographically and may lead to biopsy or unnecessary intervention. In vivoplatforms with the ability to identify tumor histology based on metabolic profiles may avoid unnecessary procedures & their complications. The metabolomics of AML have not been characterized, & research into this area may provide targetable molecules for large AMLs. In this study, we investigate the metabolomic profile of AMLs compared to clear cell RCC (ccRCC) using high resolution magic angle spinning (HRMAS) magnetic resonance spectroscopy (MRS). Methods: Tissue samples were obtained from radical or partial nephrectomy specimens that were fresh frozen & stored at -80ºC. Tissue HRMAS MRS was performed by a Bruker AVANCE spectrometer. Metabolomic profiles of RCC & adjacent benign renal tissue were compared, and false discovery rates (FDR) accounted for multiple testing. Regions of interest (ROI) with FDR <0.05 were considered potential predictors of ccRCC rather than AML. The Wilcoxon rank sum test was used to compare median MRS relative intensities for candidate predictors. Logistic regression was used to determine odds ratios for risk of malignancy based on abundance of each metabolite. Results: There were 16 ccRCC samples & 7 AML specimens. Candidate predictors of malignancy rather than AML based on FDR p-values include histidine, phenylalanine, phosphocholine, serine, alanine, glutamate, glutathione, glycerophosphocholine, & glutamine. While an abundance of these metabolites is associated with higher risk of malignancy, the odds ratio was particularly high in the 3.5-3.49 ppm spectral region (OR 2.99x106, 95% CI 3.27, 2.73x1012, p=0.033)in ccRCC samples. Conclusions: HRMAS MRS identified metabolites that may help differentiate fat-poor AML from ccRCC. In particular, metabolites in the 3.5-3.49 ppm spectral region increased the risk of harboring RCC. Our findings may contribute to future in vivostudies to help identify which patients require intervention for malignancy & which may be observed for benign AML without requiring biopsy.

Concordance of systematic and fusion biopsy with surgical pathology

93

Background: Multiparametric MRI is increasingly used in prostate cancer detection. Previous studies have shown that detection rate of clinically significant cancer is higher in MRI targeted biopsy than systematic biopsy. However, the concordance between the Gleason score on fusion biopsy and radical prostatectomy is less well known. The objective of this study is to look for predictors of histopathologic concordance between biopsy (fusion and systematic) and radical prostatectomy. Methods: We used an institutional database of men who underwent mpMRI-ultrasound fusion targeted and systematic biopsy followed by radical prostatectomy. Gleason score on targeted, systematic and combination (targeted + systematic) biopsy were compared with Gleason score on radical prostatectomy, and concordance was recorded. The McNemar test was used to compare concordance and upgrade rates. Predictors of concordance and upgrade such as age, prostate volume, PSA, PSA density, Gleason score on biopsy, number of targets reported on mpMRI, and PI-RADS score were evaluated with Fisher’s exact test and logistic regression. Results: Surgical pathology was concordant with 47.4% of systematic biopsies, 52.0% of targeted biopsies and 58.4% of combination biopsies. There was no significant difference in concordance rates between systematic and targeted biopsy (P = 0.37). However, combination biopsy was superior to both systematic (RR 1.23, 95% CI 1.08-1.40, P = 0.03) and targeted biopsy (RR 1.12, 95% CI 1.02 – 1.24, P = 0.03) in predicting concordance with surgical pathology. Risk of upgrade to a higher Gleason score on surgical pathology was significantly lower with combination biopsy compared to systematic (RR 0.57, 95% CI 0.46-0.69, P < 0.001) or targeted biopsy alone (RR 0.72, 95% CI 0.61-0.84, P = 0.001). Upgrade rates were 43.9% for systematic biopsy, 34.7% for targeted, and 24.9% for combination. Lastly, we found no significant predictors of concordance or upgrade. Conclusions: Combination biopsy is associated with the highest concordance rate between biopsy and radical prostatectomy when compared with systematic or targeted biopsy alone. Performing targeted biopsy alone will underestimate tumour aggressiveness on surgical pathology.

Current Management of Small Renal Masses, Including Patient Selection, Renal Tumor Biopsy, Active Surveillance, and Thermal Ablation

Renal cancer represents 2% to 3% of all cancers, and its incidence is rising. The increased use of ultrasonography and cross-sectional imaging has resulted in the clinical dilemma of incidentally detected small renal masses (SRMs). SRMs represent a heterogeneous group of tumors that span the full spectrum of metastatic potential, including benign, indolent, and more aggressive tumors. Currently, no composite model or biomarker exists that accurately predicts the diagnosis of kidney cancer before treatment selection, and the use of renal mass biopsy remains controversial. The management of SRMs has changed dramatically over the last two decades as our understanding of tumor biology and competing risks of mortality in this population has improved. In this review, we critically assess published consensus guidelines and recent literature on the diagnosis and management of SRMs, with a focus on patient treatment selection and use of renal mass biopsy, active surveillance, and thermal ablation. Finally, we highlight important opportunities for leveraging recent research discoveries to identify patients with SRMs at high risk for renal cell carcinoma-related mortality and minimize overtreatment and patient morbidity.

Comparative Effectiveness of Bladder-preserving Tri-modality Therapy Versus Radical Cystectomy for Muscle-invasive Bladder Cancer

INTRODUCTION

There are limited randomized data comparing radical cystectomy (RC) with bladder-sparing tri-modality therapy (TMT) in the treatment of muscle-invasive bladder cancer (MIBC). Both strategies are thought to have similar survival outcomes with different morbidity profiles. We compare the effectiveness of TMT and RC using decision-analytic modeling and the endpoint of quality-adjusted life years (QALYs).

PATIENTS AND METHODS

Using a Markov model, we simulated the lifetime outcomes after TMT versus RC ± neoadjuvant chemotherapy for 67-year-old patients with clinical stage T2-T4aN0M0 MIBC. Model probabilities and utilities were extracted from the literature. The incremental effectiveness was reported in QALYs and sensitivity analyses were performed.

RESULTS

For all patients with MIBC, although the model showed identical survival, TMT was the most effective strategy with an incremental gain of 0.59 QALYs over RC (7.83 vs. 7.24 QALYs, respectively). When limiting the model to favorable, contemporary cohorts in both the TMT and RC strategies, TMT remained more effective with an incremental gain of 1.61 QALYs (9.37 vs. 7.76 QALYs, respectively). One-way sensitivity analyses demonstrated the model was sensitive to the quality of life parameters (ie, the utilities) for RC and TMT. When testing the 95% confidence interval of the RC utility parameter the model demonstrated an incremental gain with TMT from -0.54 to 4.23 QALYs. Probabilistic sensitivity analysis demonstrated that TMT was more effective than RC for 63% of model iterations.

CONCLUSIONS

This modeling study found that treatment of MIBC with organ-sparing TMT in appropriately-selected patients may result in a gain of QALYs relative to RC.

The prognostic impact of a negative confirmatory biopsy in men on active surveillance for prostate cancer

76

Background: Active surveillance (AS) is increasingly used in managing low-risk and favorable intermediate-risk prostate cancer. To mitigate the risk of unsampled higher risk disease, most institutional AS protocols call for a confirmatory prostate biopsy within 12-18 months following initial diagnostic biopsy. Here, we investigate whether the results of confirmatory biopsy impact the outcomes of men on AS. Methods: We retrospectively reviewed our institutional database of men enrolled in AS between 1997-2014 with a minimum follow-up of 6 months (n = 974). Biopsies with any prostate cancer were considered positive. Biopsies containing only benign prostatic tissue, prostatic intraepithelial neoplasia (PIN), or atypical small acinar proliferation (ASAP) were considered negative. Statistical analysis was conducted using the Kaplan-Meier method and Cox proportional hazards regression. Results: At diagnosis, median age was 67 years (IQR 62-72) and median PSA was 5.1 ng/mL (IQR 3.9-6.8). The vast majority of patients had Gleason ≤6 (97%) and clinical stage T1 (92%) disease. With a median follow-up of 4.8 years, 702 (72%) patients underwent a confirmatory biopsy. 67% of confirmatory biopsies were positive for prostate cancer; 33% were negative (167 benign, 40 PIN, and 22 ASAP). Of the 702 patients, 33% progressed to treatment, with pathologic progression the most common reason (77%). Univariate predictors of progression to treatment included initial clinical stage ( P= 0.04), involvement of > 20% of any core on diagnostic biopsy ( P < 0.01), PSA density ≥0.15 ( P < 0.001), and confirmatory biopsy status ( P < 10-14). In multivariate analysis, a negative confirmatory biopsy remained the strongest predictor of progression to treatment (HR 0.12 [95%CI 0.06-0.24], P < 10-8). Confirmatory biopsy status was not associated with risk of adverse pathology on RP, metastasis-free survival, disease-specific survival, or overall survival. Conclusions: A negative confirmatory biopsy is associated with a significantly lower rate of progression to treatment among men on AS. This may serve as a useful tool for prognostication and help determine the need for further repeat biopsies for men on AS.

Comparative effectiveness of bladder-preserving tri-modality therapy versus radical cystectomy for muscle-invasive bladder cancer

418

Background: Radical cystectomy (RC) has historically been considered the standard of care for muscle invasive bladder cancer (MIBC). An alternative is tri-modality therapy (TMT), a bladder-sparing approach that often achieves preservation of the native bladder. There are limited randomized data comparing these guideline-recommended approaches but, in appropriately selected patients, both are thought to have similar survival outcomes with different morbidity profiles. Therefore this study compared the effectiveness of TMT and RC using decision-analytic modeling with the primary endpoint of quality-adjusted life years (QALYs). Methods: We developed a Markov model simulating the lifetime outcomes for 67-year-old patients after definitive treatment for American Joint Committee on Cancer clinical Stage T2-T4aN0M0 MIBC using two strategies: TMT or RC +/- neoadjuvant chemotherapy (NAC). Probabilities and utilities were extracted from the literature to determine the incremental effectiveness in QALYs. Sensitivity analyses were performed. Results: TMT was the most effective strategy with an incremental gain of 1.13 QALYs over RC (8.37 versus 7.24 QALYs, respectively; Table). One-way sensitivity analyses demonstrated the model was most sensitive to the quality of life (QoL) parameters (i.e. the utilities) for RC and TMT; TMT was more effective than RC irrespective of the RC utility (the 95% confidence interval of the RC parameter demonstrated an incremental gain with TMT of 0.01 to 4.77 QALYs). The model was relatively less sensitive to the probability of death for either strategy. Probabilistic sensitivity analysis demonstrated that TMT was more effective than RC for 75% of model iterations. Conclusions: Treatment of MIBC with organ-sparing TMT in appropriately-selected patients may result in a gain of over 1 QALY relative to RC. Further prospective investigation into the QoL implications of these treatment modalities is warranted. [Table: see text]