Limitations of Parenchymal Volume Analysis for Estimating Split Renal Function and New Baseline Glomerular Filtration Rate After Radical Nephrectomy

PURPOSE

Accurately predicting new baseline glomerular filtration rate (NBGFR) after radical nephrectomy (RN) can improve counseling about RN vs partial nephrectomy. Split renal function (SRF)-based models are optimal, and differential parenchymal volume analysis (PVA) is more accurate than nuclear renal scans (NRS) for this purpose. However, there are minimal data regarding the limitations of PVA. Our objective was to identify patient-/tumor-related factors associated with PVA inaccuracy.

MATERIALS AND METHODS

Five hundred and ninety-eight RN patients (2006-2021) with preoperative CT/MRI were retrospectively analyzed, with 235 also having NRS. Our SRF-based model to predict NBGFR was: 1.25 × (GlobalGFRPre-RN × SRFContralateral), where GFR indicates glomerular filtration rate, with SRF determined by PVA or NRS, and with 1.25 representing the median renal functional compensation in adults. Accuracy of predicted NBGFR within 15% of observed was evaluated in various patient/tumor cohorts using multivariable logistic regression analysis.

RESULTS

PVA and NRS accuracy were 73%/52% overall, and 71%/52% in patients with both studies (n = 235, P < .001), respectively. PVA inaccuracy independently associated with pyelonephritis, hydronephrosis, renal vein thrombosis, and infiltrative features (all P < .03). Ipsilateral hydronephrosis and renal vein thrombosis associated with PVA underprediction, while contralateral hydronephrosis and increased age associated with PVA overprediction (all P < .01). NRS inaccuracy was more common and did not associate with any of these conditions. Even among cohorts where PVA inaccuracy was observed (22% of our patients), there was no significant difference in the accuracies of NRS- and PVA-based predictions.

CONCLUSIONS

PVA was more accurate for predicting NBGFR after RN than NRS. Inaccuracy of PVA correlated with factors that distort the parenchymal volume/function relationship or alter renal functional compensation. NRS inaccuracy was more common and unpredictable, likely reflecting the inherent inaccuracy of NRS. Awareness of cohorts where PVA is less accurate can help guide clinical decision-making.

Parenchymal obliteration by renal masses: Functional and oncologic implications

OBJECTIVES

Most renal tumors merely displace nephrons while others can obliterate parenchyma in an invasive manner. Substantial parenchymal volume replacement (PVR) by renal cell carcinoma (RCC) may have oncologic implications; however, studies regarding PVR remain limited. Our objective was to evaluate the oncologic implications associated with PVR using improved methodology including more accurate and objective tools.

PATIENTS/METHODS

A total of 1,222 patients with non-metastatic renal tumors managed with partial nephrectomy (PN) or radical nephrectomy (RN) at Cleveland Clinic (2011-2014) with necessary studies were retrospectively evaluated. Parenchymal volume analysis via semiautomated software was used to estimate split renal function and preoperative parenchymal volumes. Using the contralateral kidney as a control, %PVR was defined: (parenchymal volumecontralateral-parenchymal volumeipsilateral) normalized by parenchymal volumecontralateral x100%. PVR was determined preoperatively and not altered by management. Patients were grouped by degree of PVR: minimal (<5%, N = 566), modest (5%-25%, N = 414), and prominent (≥25%, N = 142). Kaplan-Meier was used to evaluate survival outcomes relative to degree of PVR. Multivariable Cox-regression models evaluated predictors of recurrence-free survival (RFS).

RESULTS

Of 1,122 patients, 801 (71%) were selected for PN and 321 (29%) for RN. Overall, median tumor size was 3.1 cm and 6.8 cm for PN and RN, respectively, and median follow-up was 8.6 years. Median %PVR was 15% (IQR = 6%-29%) for patients selected for RN and negligible for those selected for PN. %PVR correlated inversely with preoperative ipsilateral GFR (r = -0.49, P < 0.01) and directly with advanced pathologic stage, high tumor grade, clear cell histology, and sarcomatoid features (all P < 0.01). PVR≥25% associated with shortened recurrence-free, cancer-specific, and overall survival (all P < 0.01). Male sex, ≥pT3a, tumor grade 4, positive surgical margins, and PVR≥25% independently associated with reduced RFS (all P < 0.02).

CONCLUSIONS

Obliteration of normal parenchyma by RCC substantially impacts preoperative renal function and patient selection. Our data suggests that increased PVR is primarily driven by aggressive tumor characteristics and independently associates with reduced RFS, although further studies will be needed to substantiate our findings.

Thermal Ablation Versus Partial Nephrectomy for cT1 Renal Mass in a Solitary Kidney: A Matched Cohort Comparative Analysis

BACKGROUND

Nephron-sparing approaches are preferred for renal mass in a solitary kidney (RMSK), with partial nephrectomy (PN) generally prioritized. Thermal ablation (TA) also is an option for small renal masses in this setting; however, comparative functional/survival outcomes are not well-defined.

METHODS

A retrospective study of 504 patients (1975-2022) with cT1 RMSK managed with PN (n = 409)/TA (n = 95) with necessary data for analysis was performed. Propensity score was used for matching patients, including age, preoperative glomerular filtration rate (GFR), tumor diameter, R.E.N.A.L. ((R)adius (tumor size as maximal diameter), (E)xophytic/endophytic properties of tumor, (N)earness of tumor deepest portion to collecting system or sinus, (A)nterior (a)/posterior (p) descriptor, and (L)ocation relative to polar lines), and comorbidities. Functional outcomes were compared, and Kaplan-Meier was used to analyze survival.

RESULTS

The matched cohort included 132 patients (TA = 66/PN = 66), with median tumor diameter of 2.4 cm, R.E.N.A.L. of 6, and preoperative GFR of 52 ml/min/1.73 m2. Acute kidney injury occurred in 11%/61% in the TA/PN cohorts, respectively (p < 0.01). After recovery, median GFR preserved was 89%/83% for TA/PN, respectively (p = 0.02), and 5-year dialysis-free survival was 96% in both cohorts. Median follow-up was 53 months. Five-year recurrence-free survival (RFS) was 62%/86% in the TA/PN cohorts, respectively (p < 0.01). Five-year local recurrence (LR)-free survival was 74%/95% in the TA/PN cohorts, respectively (p < 0.01). Five-year cancer-specific survival (CSS) was 96%/98% in the TA/PN cohorts, respectively (p = 0.7). Local recurrence was observed in nine of 36 (25%) and five of 30 (17%) patients managed with laparoscopic versus percutaneous TA, respectively. For TA with LR (n = 14), nine patients presented with multifocality and/or cT1b tumors. Twelve LR were managed with salvage TA, and seven remained cancer-free, while five developed systemic recurrence, three with concomitant LR.

CONCLUSIONS

Functional outcomes for TA for RMSK were improved compared with PN. Local recurrence was more common after TA and often was associated with the laparoscopic approach, multifocality, and large tumor size. Improved patient selection and greater experience with TA should improve outcomes. Salvage of LR was not always possible. Partial nephrectomy remains the reference standard for RMSK.

Oncologic outcomes of intravesical therapy in the management of nonmuscle invasive bladder cancer with variant histology

PURPOSE

There is limited data on oncologic outcomes in nonmuscle invasive bladder cancer (NMIBC) with variant histology (VH) managed with intravesical therapy. We sought to evaluate oncologic outcomes for this cohort at a high-volume center.

MATERIALS AND METHODS

A retrospective review of an IRB-approved bladder cancer database was performed. Patients with a history of NMIBC with VH present on transurethral resection of bladder tumor (TURBT) treated with intravesical therapy (BCG or chemotherapy) were identified. Outcomes of interest included recurrence within the bladder, progression to muscle-invasive bladder cancer (MIBC), metastatic progression, cancer-specific, and overall survival. Survival time was computed from the date of initiation of intravesical therapy to the date of event or censoring. For patients who underwent radical cystectomy, recurrence-free, cancer-specific, and overall survival were also computed. The Kaplan-Meier method with log rank was utilized to compare survival time between VH sub-groups.

RESULTS

Ninety patients were included in the final cohort with a median follow-up of 38 months. The majority of patients had T1 disease (72%) and received intravesical BCG (83%) as their only form of intravesical therapy. The most commonly represented VH in this series were glandular and squamous differentiation (26%). Forty-eight patients (53%) experienced recurrence within the bladder with a median recurrence-free survival of 24 months (95% Confidence Interval [CI]: 2-46 months). Five-year rates of progression to MIBC and distant metastasis were both 14% respectively. Twenty-six patients (28%) eventually required cystectomy. When stratifying by VH, patients with sarcomatoid, plasmacytoid, and micropapillary had significantly worse oncologic outcomes.

CONCLUSION

In this series of highly-selected patients with NMIBC and VH, bladder-sparing treatment with intravesical therapy demonstrated acceptable oncologic outcomes for most VHs. This may be an acceptable treatment option for patients without plasmacytoid, sarcomatoid, or micropapillary features who are not suitable cystectomy candidates or who prioritize bladder-sparing treatment.

Parenchymal volume preservation during partial nephrectomy: improved methodology to assess impact and predictive factors

OBJECTIVE

To rigorously evaluate the impact of the percentage of parenchymal volume preserved (PPVP) and how well the preserved parenchyma recovers from ischaemia (Recischaemia ) on functional outcomes after partial nephrectomy (PN) using an accurate and objective software-based methodology for estimating parenchymal volumes and split renal function (SRF). A secondary objective was to assess potential predictors of the PPVP.

PATIENTS AND METHODS

A total of 894 PN patients with available studies (2011-2014) were evaluated. The PPVP was measured from cross-sectional imaging at ≤3 months before and 3-12 months after PN using semi-automated software. Pearson correlation evaluated relationships between continuous variables. Multivariable linear regression evaluated predictors of ipsilateral glomerular filtration rate (GFR) preserved and the PPVP. Relative-importance analysis was used to evaluate the impact of the PPVP on ipsilateral GFR preserved. Recischaemia was defined as the percentage of ipsilateral GFR preserved normalised by the PPVP.

RESULTS

The median tumour size and R.E.N.A.L. nephrometry score were 3.4 cm and 7, respectively. In all, 49 patients (5.5%) had a solitary kidney. In all, 538 (60%)/251 (28%)/104 (12%) patients were managed with warm/cold/zero ischaemia, respectively. The median pre/post ipsilateral GFRs were 40/31 mL/min/1.73 m2 , and the median (interquartile range [IQR]) percentage of ipsilateral GFR preserved was 80% (71-88%). The median pre/post ipsilateral parenchymal volumes were 181/149 mL, and the median (IQR) PPVP was 84% (76-92%). In all, 330 patients (37%) had a PPVP of <80%, while only 34 (4%) had a Recischaemia of <80%. The percentage of ipsilateral GFR preserved correlated strongly with the PPVP (r = 0.83, P < 0.01) and loss of parenchymal volume accounted for 80% of the loss of ipsilateral GFR. Multivariable analysis confirmed that the PPVP was the strongest predictor of ipsilateral GFR preserved. Greater tumour size and endophytic and nearness properties of the R.E.N.A.L. nephrometry score were associated with a reduced PPVP (all P ≤ 0.01). Solitary kidney and cold ischaemia were associated with an increased PPVP (all P < 0.05).

CONCLUSIONS

A reduced PPVP predominates regarding functional decline after PN, although a low Recischaemia can also contribute. Tumour-related factors strongly influence the PPVP, while surgical efforts can improve the PPVP as observed for patients with solitary kidneys.

Functional recovery after partial nephrectomy in a solitary kidney

OBJECTIVES

Partial nephrectomy (PN) is the reference standard for renal mass in a solitary kidney (RMSK), although factors determining functional recovery in this setting remain poorly defined.

PATIENTS/METHODS

Single center, retrospective analysis of 841 RMSK patients (1975-2022) managed with PN with functional data, including 361/435/45 with cold/warm/zero ischemia, respectively. A total of 155 of these patients also had necessary studies for detailed analysis of parenchymal volume preserved. Acute kidney injury (AKI) was classified by RIFLE (Risk/Injury/Failure/Loss/Endstage). Recovery-from-ischemia (Rec-Ischemia) was defined as glomerular filtration rate (GFR) saved normalized by parenchymal volume saved. Logistic regression identified predictive factors for AKI and predictors of Rec-Ischemia were analyzed by multivariable linear regression.

RESULTS

Overall, median preoperative GFR was 56.7 ml/min/1.73m2 and new-baseline and 5-year GFRs were 43.1 and 44.5 ml/min/1.73m2, respectively. Median follow-up was 55 months; 5-year dialysis-free survival was 97%. In the detailed analysis cohort, a primary focus of this study, median warm (n = 70)/cold (n = 85) ischemia times were 25/34 minutes, respectively; and median preoperative, new-baseline and 5-year GFRs were 57.8, 45.0, and 41.7 ml/min/1.73m2, respectively. Functional recovery correlated strongly with parenchymal volume preserved (r = 0.84, p < 0.001). Parenchymal volume loss accounted for 69% of the total median GFR decline associated with PN, leaving only 3 to 4 ml/min/1.73m2 attributed to ischemia and other factors. AKI occurred in 52% of patients and the only independent predictor of AKI was ischemia time. Independent predictors of reduced Rec-Ischemia were increased age, warm ischemia, and AKI.

CONCLUSION

The main determinant of functional recovery after PN in RMSK is parenchymal volume preservation. Type/duration of ischemia, AKI, and age also correlated, although altogether their contributions were less impactful. Our findings suggest multiple opportunities for optimizing functional outcomes although preservation of parenchymal volume remains predominant. Long-term function generally remains stable with dialysis only occasionally required.

Parenchymal volume analysis to assess longitudinal functional decline following partial nephrectomy

OBJECTIVE

To identify factors associated with longitudinal ipsilateral functional decline after partial nephrectomy (PN).

PATIENTS AND METHODS

Of 1140 patients managed with PN (2012-2014), 349 (31%) had imaging/serum creatinine levels pre-PN, 1-12 months post-PN (new baseline), and >3 years later necessary for inclusion. Parenchymal-volume analysis was used to determine split renal function. Patients were grouped as having significant renal comorbidity (CohortSRC : diabetes mellitus with insulin-dependence or end-organ damage, refractory hypertension, or severe pre-existing chronic kidney disease) vs not having significant renal comorbidity (CohortNoSRC ) preoperatively. Multivariable regression was used to identify predictors of annual ipsilateral parenchymal atrophy and functional decline relative to new baseline values post-PN, after the kidney had healed.

RESULTS

The median follow-up was 6.3 years with 87/226/36 patients having cold/warm/zero ischaemia. The median cold/warm ischaemia times were 32/22 min. Overall, the median tumour size was 3.0 cm. The preoperative glomerular filtration rate (GFR) and new baseline GFR (NBGFR) were 81 and 71 mL/min/1.73 m2 , respectively. After establishment of the NBGFR, the median loss of global and ipsilateral function was 0.7 and 0.4 mL/min/1.73 m2 /year, respectively, consistent with the natural ageing process. Overall, the median ipsilateral parenchymal atrophy was 1.2 cm3 /year and accounted for a median of 53% of the annual functional decline. Significant renal comorbidity, age, and warm ischaemia were independently associated with ipsilateral parenchymal atrophy (all P < 0.01). Significant renal comorbidity and ipsilateral parenchymal atrophy were independently associated with annual ipsilateral functional decline (both P < 0.01). Annual median ipsilateral parenchymal atrophy and functional decline were both significantly increased for CohortSRC compared to CohortNoSRC (2.8 vs 0.9 cm3 , P < 0.01 and 0.90 vs 0.30 mL/min/1.73 m2 /year, P < 0.01, respectively).

CONCLUSIONS

Longitudinal renal function following PN generally follows the normal ageing process. Significant renal comorbidities, age, warm ischaemia, and ipsilateral parenchymal atrophy were the most important predictors of ipsilateral functional decline following establishment of NBGFR.

Robot Partial Prostatectomy for Anterior Cancer: Long-term Functional and Oncological Outcomes at 7 Years

Partial prostatectomy has been described as an alternative to focal ablation therapy for the management of localized low- to intermediate-risk prostate cancer. This report aims to describe the long-term outcomes in a series of 28 men (2000-2022) who underwent robotic-assisted anterior partial prostatectomy (APP) for anteriorly located tumors entirely or partially within the anterior fibromuscular stroma. The median follow-up is 7 yr (interquartile range [IQR]: 4.2-8). The median prostate-specific antigen (PSA) before APP was 9.6 (6-11). Continence remained uninterrupted in 92% of patients. Erectile function without drug remained uninterrupted in 69%. The median nadir PSA after APP was 0.36 ng/ml (IQR: 0.25-0.60). Cancer recurrence at biopsies at the margins of the primary cancer resected area in case of a PSA elevation was observed in eight patients and led to salvage completion robotic radical prostatectomy at a median time of 3.25 yr (IQR: 2.4-6). Freedom from post-APP cancer recurrence at 7 yr was 62.7% (35.0-81.3%). Pre-APP tumor volume at magnetic resonance imaging (MRI) and volume of grade 4/5 were predictive of recurrence. Freedom from biochemical recurrence after completion radical prostatectomy at 7 yr was 94.7% (68.1-99.3%). All 28 patients are alive. No one had systemic treatment or metastases. These results confirm our initial report of robotic APP with good functional results and acceptable oncological results. The use of the inclusion criteria of pre-APP tumor volume at MRI <3 cc may decrease the risk of recurrence.

Patient summary

In this report, we looked at outcomes for infrequent cases of anterior prostate cancer treated with anterior partial prostatectomy, an uncommon surgical procedure as an alternative to in situ focal ablation therapy, to better preserve functional outcomes as compared with whole gland therapy. We found that functional outcomes of uninterrupted continence and erectile function were good. Out of 28 patients, eight had recurrence in the remaining prostate and were treated with a second surgical procedure, radical prostatectomy, which was feasible. We conclude that this new technique is feasible with good functional results and acceptable oncological results, which can be shared with the patients.

Functional recovery after partial nephrectomy: next generation analysis

OBJECTIVES

To provide a more rigorous assessment of factors affecting functional recovery after partial nephrectomy (PN) using novel tools that allow for analysis of more patients and improved accuracy for assessment of parenchymal volume loss, thereby revealing the potential impact of secondary factors such as ischaemia.

PATIENTS AND METHODS

Of 1140 patients managed with PN (2012-2014), 670 (59%) had imaging and serum creatinine levels measured before and after PN necessary for inclusion. Recovery from ischaemia was defined as the ipsilateral glomerular filtration rate (GFR) saved normalised by parenchymal volume saved. Acute kidney injury was assessed through Spectrum Score, which quantifies the degree of acute ipsilateral renal dysfunction due to exposure to ischaemia that would otherwise be masked by the contralateral kidney. Multivariable regression was used to identify predictors of Spectrum Score and Recovery from Ischaemia.

RESULTS

In all, 409/189/72 patients had warm/cold/zero ischaemia, respectively, with median (interquartile range [IQR]) ischaemia times for cold and warm ischaemia of 30 (25-42) and 22 (18-28) min, respectively. The median (IQR) global preoperative GFR and new baseline GFR (NBGFR) were 78 (63-92) and 69 (54-81) mL/min/1.73 m2 , respectively. The median (IQR) ipsilateral preoperative GFR and NBGFR were 40 (33-47) and 31 (24-38) mL/min/1.73 m2 , respectively. Functional recovery correlated strongly with parenchymal volume preserved (r = 0.83, P < 0.01). The median (IQR) decline in ipsilateral GFR associated with PN was 7.8 (4.5-12) mL/min/1.73 m2 with loss of parenchyma accounting for 81% of this loss. The median (IQR) recovery from ischaemia was similar across the cold/warm/zero ischaemia groups at 96% (90%-102%), 95% (89%-101%), and 97% (91%-102%), respectively. Independent predictors of Spectrum Score were ischaemia time, tumour complexity, and preoperative global GFR. Independent predictors of recovery from ischaemia were insulin-dependent diabetes mellitus, refractory hypertension, warm ischaemia, and Spectrum Score.

CONCLUSIONS

The main determinant of functional recovery after PN is parenchymal volume preservation. A more robust and rigorous evaluation allowed us to identify secondary factors including comorbidities, increased tumour complexity, and ischaemia-related factors that are also independently associated with impaired recovery, although altogether these were much less impactful.

Selective Use of Neoadjuvant Targeted Therapy Is Associated with Greater Achievement of Partial Nephrectomy for High-complexity Renal Masses in a Solitary Kidney

Background

Partial nephrectomy (PN) is preferred for a renal mass in a solitary kidney (RMSK), although tumors with high complexity can be challenging.

Objective

To evaluate the evolution of RMSK management with a focus on achievement of PN.

Design setting and participants

Patients with nonmetastatic RMSK (n = 499) were retrospectively reviewed; 133 had high tumor complexity, including 80 in the pre-tyrosine kinase inhibitor (TKI) era (1999-2008) and 53 in the TKI era (2009-2022). After 2009, 23/53 patients received neoadjuvant TKI and 30/53 had immediate-surgery.

Outcome measurements and statistical analysis

Functional outcomes, adverse events and complications, dialysis-free survival, and recurrence-free survival (RFS) were the measures evaluated. Mann-Whitney and χ2 tests were used to compare cohorts, and the log-rank test was applied for survival analyses.

Results and limitations

Overall, the median RENAL score was 10 and the median tumor diameter was 5.2 cm. Demographic characteristics, tumor diameter, and RENAL scores were similar between the pre-TKI-era and TKI-era groups. In the TKI era, 23/53 patients (43%) with clear-cell histology were selected for neoadjuvant TKI. These 23 patients had a greater median tumor diameter (7.1 vs 4.4 cm; p = 0.02) and RENAL score (11 vs 10; p = 0.07). After TKI treatment, the median tumor diameter decreased to 5.6 cm and the RENAL score to 9, and tumor volume was reduced by 59% (all p < 0.05). PN was accomplished in 21/23 (91%) the TKI-treated cases and in 27/30 (90%) of the immediate-surgery cases (2009-2022). PN was only accomplished in 52/80 (65%) of the patients from the pre-TKI era (p < 0.01). The 5-yr dialysis-free survival rate was 59% in the pre-TKI-era group and 91% in the TKI-era group. The 5-yr RFS rate was lower in the TKI-era group (59% vs 74%; p = 0.21), which was mostly related to more aggressive tumor biology, as reflected by a predominance of systemic rather than local recurrences.

Conclusions

Management of RMSK with high tumor complexity is challenging. Selective use of TKI therapy was associated with greater use of PN, although a randomized study is needed. RFS mostly reflected aggressive tumor biology rather than failure of local management.

Patient summary

For complex kidney tumors in patients with a single kidney, management is challenging. Use of drugs called tyrosine kinase inhibitors before surgery was associated with reductions in tumor size and greater ability to achieve partial kidney removal for cancer control. Most recurrences were metastatic, which reflects aggressive tumor biology rather than failure of surgery.

Using IsoPSA With Prostate Imaging Reporting and Data System Score May Help Refine Biopsy Decision Making in Patients With Elevated PSA

OBJECTIVE

To assess how IsoPSA, a structure-based serum assay which has been prospectively validated in detecting clinically significant prostate cancer (csPCa), can help the biopsy decision process when combined with the prostate imaging reporting and data systems (PI-RADS).

MATERIALS AND METHODS

This was a single-center retrospective review of prospectively collected data on patients receiving IsoPSA testing for elevated PSA (>4.0ng/mL). Patients were included if they had received an IsoPSA test and prostate MRI within 1 year of IsoPSA testing, and subsequently underwent prostate biopsy. Multivariable logistic regression was used to identify predictors of (csPCa, ie, GG ≥ 2) on biopsy. Predictive probabilities for csPCa at biopsy were generated using IsoPSA and various PI-RADS scores.

RESULTS

Two hundred and 7 patients were included. Twenty-two percent had csPCa. Elevated IsoPSA ratio (defined as ≥6.0) (OR: 5.06, P = .015) and a PI-RADS 4-5 (OR: 6.37, P <.001) were significant predictors of csPCa. The combination of elevated IsoPSA ratio and PI-RADS 4-5 lesion had the highest area under the curve (AUC) (AUC: 0.83, P <.001). The predicted probability of csPCa when a patient had a negative or equivocal MRI (PI-RADS 1-3) and a low IsoPSA ratio (≤6) was <5%.

CONCLUSION

The combination of PI-RADS with IsoPSA ratios may help refine the biopsy decision-making process. In our cohort, a negative or equivocal MRI with a low IsoPSA may provide a low enough predicted probability to omit biopsy in such patients.

Factors predicting the active treatment of renal angiomyolipoma: 30 years of experience in two tertiary referral centers

Introduction and objective

This study aimed to identify clinical features representing predictive factors of active treatment (AT) compared to active surveillance (AS) for renal angiomyolipoma (AML).

Patients and methods

From 1990 to 2020, patients referred to two institutions for a renal mass and diagnosed with an AML based on typical features on CT were included in the analysis. The study population was divided into two groups based on the treatment received: active surveillance (AS) or active treatment (AT). Age, gender, tuberous sclerosis syndrome, tumor size, contralateral kidney disease, renal function, year of diagnosis, and symptoms at presentation were assessed as potential predictive factors of active treatment using a logistic regression model in univariate and multivariate analyses.

Results

In total, 253 patients (mean age 52.3 ± 15.7 years; 70% women; 70.9% incidentally diagnosed) were included in the analysis. One hundred and nine (43%) received AS, whereas 144 (57%) were actively treated. For univariate analysis, age, tuberous sclerosis complex syndrome, tumor size, symptoms at presentation, and contralateral kidney disease were found to be predictors of AT. Only tumor size (p < 0.001) and the year of diagnosis (p < 0.001) remained significant for multivariable analyses. The likelihood of being managed with AS evolved over the study period and was 50% and 75% when diagnosed before and after 2010, respectively. With respect to size, 4-cm and 6-cm tumors had a probability of 50% and 75% of being treated with AS, respectively.

Conclusion

The present analysis from a high-volume institution provides evidence that the management of renal masses with typical radiological features of AML has markedly changed over the last three decades with a trend toward AS over AT. Tumor size and the year of diagnosis were significant factors for the treatment strategies.

KDM6A Loss Triggers an Epigenetic Switch That Disrupts Urothelial Differentiation and Drives Cell Proliferation in Bladder Cancer

Disruption of KDM6A, a histone lysine demethylase, is one of the most common somatic alternations in bladder cancer. Insights into how KDM6A mutations affect the epigenetic landscape to promote carcinogenesis could help reveal potential new treatment approaches. Here, we demonstrated that KDM6A loss triggers an epigenetic switch that disrupts urothelial differentiation and induces a neoplastic state characterized by increased cell proliferation. In bladder cancer cells with intact KDM6A, FOXA1 interacted with KDM6A to activate genes instructing urothelial differentiation. KDM6A-deficient cells displayed simultaneous loss of FOXA1 target binding and genome-wide redistribution of the bZIP transcription factor ATF3, which in turn repressed FOXA1-target genes and activated cell-cycle progression genes. Importantly, ATF3 depletion reversed the cell proliferation phenotype induced by KDM6A deficiency. These data establish that KDM6A loss engenders an epigenetic state that drives tumor growth in an ATF3-dependent manner, creating a potentially targetable molecular vulnerability.

SIGNIFICANCE

A gain-of-function epigenetic switch that disrupts differentiation is triggered by inactivating KDM6A mutations in bladder cancer and can serve as a potential target for novel therapies.

Comprehensive Management of Renal Masses in Solitary Kidneys

BACKGROUND

A renal mass in a solitary kidney (RMSK) has traditionally been managed with partial nephrectomy (PN), although radical nephrectomy (RN) is occasionally required. Most RMSK studies have focused on patients for whom PN was achieved.

OBJECTIVE

To provide a comprehensive analysis of the management strategies/outcomes for an RMSK and address knowledge deficits regarding this challenging disorder.

DESIGN, SETTING, AND PARTICIPANTS

A total of 1024 patients diagnosed with an RMSK (1975-2022) were retrospectively evaluated. Baseline characteristics and pathologic/functional/survival outcomes were analyzed.

INTERVENTION

PN/RN/cryoablation (CA)/active surveillance (AS).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Functional outcomes, perioperative morbidity/mortality, and 5-yr recurrence-free survival (RFS) were evaluated. Kruskal-Wallis and chi-square tests were used to compare cohorts, and log-rank test and Cox proportional hazard model were used for survival analysis.

RESULTS AND LIMITATIONS

Of 1024 patients, 842 underwent PN (82%), 102 CA (10%), 54 RN (5%), and 26 AS (3%). The median tumor size and RENAL([R]adius [tumor size as maximal diameter], [E]xophytic/endophytic properties of tumor, [N]earness of tumor deepest portion to collecting system or sinus, [A]nterior [a]/posterior [p] descriptor, and [L]ocation relative to polar lines) score were 3.7 cm and 8, respectively. The median follow-up was 53 mo. For PN, 95% were clamped, and the median warm and cold ischemia times were 22 and 45 min, respectively. For PN, the median preoperative glomerular filtration rate (GFR) was 57 ml/min/1.73 m², and the median new baseline and 5-yr GFRs were 47 and 48 ml/min/1.73 m², respectively. Dialysis-free survival for PN was 97% at 5 yr. Twenty-two (2.1%) patients with clear-cell renal cell carcinoma and RENAL score ≥10 (median = 11) received tyrosine kinase inhibitors (TKIs) to facilitate PN, leading to 57% median decrease of tumor volume; PN was accomplished in 20 (91%). Forty-one patients had planned RN (4.0%), most often due to severe pre-existing chronic kidney disease (CKD), and 13 were converted from PN to RN (1.5%). Clavien III-V perioperative complications were observed in 80 (8%) patients and 90-d mortality was 0.6%. Five-year RFS for PN, CA, and RN were 83%, 80%, and 72%, respectively (p = 0.03 for PN vs RN).

CONCLUSIONS

Nephron-sparing approaches are feasible and successful in most RMSK patients. PN for an RMSK is often challenging but can be facilitated by selective use of TKIs. RN is occasionally required due to severe CKD, over-riding oncologic concerns, or conversion from PN. This is the first large RMSK study to provide a comprehensive analysis of all management strategies/outcomes.

PATIENT SUMMARY

Kidney cancer in a solitary kidney is a major challenge for achieving cancer-free status and avoiding dialysis. Although partial nephrectomy is the principal treatment for a renal mass in a solitary kidney, other options are occasionally required to optimize outcomes.

Partial Versus Radical Nephrectomy: Complexity of Decision-Making and Utility of AUA Guidelines

INTRODUCTION

The American-Urological-Association(AUA) Guidelines for renal cancer(2017) recommend consideration for radical-nephrectomy(RN) over partial(PN) whenever there is increased oncologic-risk; and RN should be prioritized if three other criteria are all also met: 1) increased tumor-complexity; 2) no preexisting chronic-kidney-disease/ proteinuria, and 3) normal contralateral kidney that will likely provide estimated glomerular-filtration-rate (eGFR) >45ml/min/1.73m² even if RN is performed. Our objective was to assess the complexity of decision-making about RN/PN and utility of AUA Guidelines statements regarding this issue.

PATIENTS AND METHODS

Retrospective review of 267 consecutive RN/PN from 2019(100-RN/167-PN). High tumor-complexity was defined as R.E.N.A.L.≥9. Increased oncologic-risk was defined as tumor >7cm, locally-advanced or infiltrative-features on imaging, or high-risk pathology on biopsy, if obtained. New-baseline GFR after RN was estimated using global-GFR, split-renal-function_{contralateral}, and presuming 25% renal-functional-compensation.

RESULTS

163 patients(61%) fit scenarios that are well-defined in the Guidelines. Of these, 34 had strong indications for RN, and all had RN. Twelve of 129 patients(9.3%) underwent RN despite Guidelines generally favoring PN. The remaining 104 patients(39%) did not fit within situations where the Guidelines provide specific recommendations. In these patients, RN was often performed despite functional-considerations favoring PN due to overriding concerns about oncologic-risk and/or tumor-complexity.

CONCLUSION

Our data demonstrate complexity of decision-making about PN/RN as almost 40% of patients did not fit well-described AUA Guidelines descriptors. Compliance was generally strong although occasional overutilization of RN remains a concern in our series, and will be addressed with additional education. Further studies will be required to assess the generalizability of our findings in other institutions/settings.

Single-cell and spatial mapping Identify cell types and signaling Networks in the human ureter

Tissue engineering offers a promising treatment strategy for ureteral strictures, but its success requires an in-depth understanding of the architecture, cellular heterogeneity, and signaling pathways underlying tissue regeneration. Here, we define and spatially map cell populations within the human ureter using single-cell RNA sequencing, spatial gene expression, and immunofluorescence approaches. We focus on the stromal and urothelial cell populations to enumerate the distinct cell types composing the human ureter and infer potential cell-cell communication networks underpinning the bi-directional crosstalk between these compartments. Furthermore, we analyze and experimentally validate the importance of the sonic hedgehog (SHH) signaling pathway in adult progenitor cell maintenance. The SHH-expressing basal cells support organoid generation in vitro and accurately predict the differentiation trajectory from basal progenitor cells to terminally differentiated umbrella cells. Our results highlight the essential processes involved in adult ureter tissue homeostasis and provide a blueprint for guiding ureter tissue engineering.

Prognostic factors and clinical outcomes in patients with upper tract urothelial carcinoma undergoing surgery: The Cleveland Clinic experience

4593

Background: Upper tract urothelial carcinoma (UTUC) is a rare and heterogeneous disease accounting for approximately 5-10% of UC. While tumor grade and stage are known prognostic factors, data on other factors affecting outcomes in UTUC patients (pts) undergoing surgery is scant. We studied effect of various clinical factors and treatment on outcomes in UTUC. Methods: This is a single-institution retrospective study of 607 pts with UTUC undergoing surgery (nephroureterectomy (NU) or ureterectomy (U)) between Jan 2000 and Dec 2020. We studied effect of demographics, clinicopathological features, tumor location, preoperative Neutrophil-to-Lymphocyte ratio (NLR) and Albumin-to-Globulin ratio (AGR) and use of neoadjuvant or adjuvant chemotherapy on overall survival (OS) and recurrence free survival (RFS). Results: Of the 607 pts 401 (66.06%) were males and 355 (58.48%) were > 70 yrs; 232 pts (38.22%) had UTUC of renal pelvis, 242 (39.87%) of ureter and 133 (21.91%) of both. 542 pts (89.29%) underwent radical NU and 65 (10.71%) segmental U; 328 patients (54.04%) were diagnosed with muscle invasive UC (MIUC) ( > / = pT2) and 276 (45.47%) with non-MIUC ( < / = pT2). Only 51 (8.4%) pts had lymph node positive (N+) disease. Lymphovascular invasion (LVI) was identified in 163 (26.85%) and carcinoma- in-situ (CIS) in 163 (26.85%) pts. Surgical margins were positive in 92 pts (15.16%). Median NLR cutoff was 3.25 and AGR cutoff was 1.25 (dichotomized based on literature). 44 pts (7.2%) received Neoadjuvant chemotherapy and 49 pts (8%) received adjuvant chemotherapy. Tumor recurrence occurred in 216 pts (35.58%) of which 65% were at urothelial and 35% at non-urothelial sites. With median follow up of 35.2 mos, median OS was 82.69 mos and 5-yr OS rate was 60%; median RFS was 29.47 mos and 5-yr RFS rate was 40%. High grade, age > / = 70 yrs, high NLR, low AGR, presence of LVI, positive margins, CIS, MIUC, N+ disease were associated with worse outcomes. Pts with only renal pelvis involvement had better OS. Conclusions: In this large, long term follow-up series of UTUC pts, we identified several prognostic factors besides grade and stage that impact outcomes. These findings warrant further validation for use in clinical practice. [Table: see text]

First Report of Testicular Replantation Following Wrong-Site Surgery

Testicular replantation represents a unique circumstance. There are very few reports documenting their experience with testicle replantation and to the best of the authors' knowledge, this is the first case that has been reported in the peer-reviewed literature following a wrong site surgery. Therefore, we detail our technique and outcome when faced with such a rare event. In addition we review the literature, in order to compare and report the experience of others. This case highlights the value of applied microsurgical knowledge and the importance of cross-disciplinary efforts to improve patient outcomes.

Survival outcomes following radical cystectomy in patients with prior pelvic radiation for prostate cancer: A matched cohort analysis

OBJECTIVES

To determine the impact of prior pelvic radiation therapy (XRT) on outcomes following radical cystectomy (RC) for bladder cancer.

MATERIALS AND METHODS

We performed a retrospective review comparing patients with bladder cancer requiring RC and prior history of XRT for prostate cancer to those undergoing RC without XRT history at our institution from 2011-2018. Propensity score matching was performed with the following variables: age, chronic kidney disease, nutritional deficiency, neoadjuvant chemotherapy use, Charlson comorbidity index, surgical approach, urinary diversion type, and pathologic T-stage. Perioperative, pathologic and oncologic outcomes were analyzed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Categorical variables were assessed utilizing the Pearson Chi Square Test, and continuous variables with the Wilcoxon rank-sum test. The Kaplan-Meier method with stratified-log rank was used to compare survival outcomes. Multivariable Cox proportional hazards models were utilized to identify predictors of overall and recurrence free survival.

RESULTS

227 patients were included, of which 47 had radiotherapy for prostate cancer. 47% of patients in the radiation cohort received external beam radiation therapy, 47% received brachytherapy and 7% received both. There were no differences in recurrence-free survival (P = 0.82) or overall survival (P = 0.25). Statistically significant differences in perioperative or postoperative outcomes such as 90-day complication, readmission, mortality rates, or ureteroenteric anastomotic stricture rates were not found. Rates of node-positive disease, median lymph node yield, positive surgical margin rates, lymphovascular invasion, or variant histology were not significantly different between cohorts.

CONCLUSIONS

After matching for T-stage and other clinical variables, history of pelvic XRT for prostate cancer in patients who later required RC for bladder cancer, was not associated with an increased rate of perioperative complications or an independent predictor of RFS or OS.

Comparison of Oncologic Outcomes Following Open and Robotic-assisted Radical Cystectomy with both Extracorporeal and Intracorporeal Urinary Diversion

OBJECTIVES

To compare oncologic endpoints between open radical cystectomy (ORC) and robotic-assisted radical cystectomy with extracorporeal urinary diversion (eRARC) or intracorporeal urinary diversion (iRARC).

MATERIALS AND METHODS

Retrospective review of all patients undergoing curative-intent radical cystectomy with urinary diversion for urothelial bladder cancer at a single-institution from 2010-2018. Primary outcomes included recurrence location and rates, recurrence-free (RFS) and overall survival (OS). Survival estimates were obtained using the Kaplan-Meier method and compared using log-rank analysis. Cox proportional-hazards model was used to identify predictors of survival.

RESULTS

265, 366 and 285 patients underwent ORC, eRARC, and iRARC, respectively (n = 916). Median follow-up was 52, 40 and 37 months for ORC, eRARC and iRARC, respectively (P < 0.001). Ileal conduit was more commonly performed in iRARC (85%, P < 0.001). Neobladder rates did not vary. Neoadjuvant (p=0.4) or adjuvant therapy use (P = 0.36), pT-stage (P = 0.28) or pN-stage (P = 0.1) did not differ. Positive soft tissue margin rates were higher in ORC (7.2%-ORC, 3.6%-eRARC, 3.2%-iRARC, P = 0.041). Differences in recurrence rates or location were not observed. Surgical approach was not associated with any survival endpoint on proportional-hazards or Kaplan-Meier analysis. Hazard ratios and 95% CI for RFS were 1 (0.72-14) and 0.93 (0.66-1.3) for eRARC and iRARC, respectively, when compared to ORC as the referent.

CONCLUSION

These findings from a large, single-institution in conjunction with randomized-controlled trial data suggest that RARC does not compromise perioperative or long-term oncologic outcomes when compared to ORC.

Comparison of renal function after open radical cystectomy, extracorporeal robot assisted radical cystectomy, and intracorporeal robot assisted radical cystectomy

PURPOSE

Renal function outcomes following robot-assisted radical cystectomy (RARC) have not been well established. We sought to compare long-term renal function outcomes between open radical cystectomy, RARC with extracorporeal urinary diversion and intracorporeal urinary diversion at a high volume institution.

MATERIALS AND METHODS

We retrospectively reviewed our institutional bladder cancer database for patients who underwent RC from 2010 to 2019 with pre-operative estimated glomerular filtration rate (eGFR) > 45 ml/min/1.73m². Changes in renal function were assessed through locally weighted scatter plot smoothing and comparison of median eGFR between surgical groups. Chronic Kidney Disease Stage 3B was defined as eGFR < 45 ml/min/1.73m². Renal function decline was defined as a ≥10 ml/min/1.73m² drop in eGFR. Kaplan Meier method with log-rank was used to compare CKD 3B-free survival and renal function decline. Cox Proportional Hazards model was used to identify predictors of CKD 3B.

RESULTS

Six hundred and forty four patients were included with median follow-up of 32 months (IQR 12-56). Preoperative characteristics were similar among the groups with no differences in median pre-operative eGFR (ORC: 74.6, extracorporeal urinary diversion: 74.3, intracorporeal urinary diversion: 71.6 ml/min/1.73m², P=0.15). Median postoperative eGFR on follow up was not different between groups (P=0.56). 33% of patients developed CKD 3B. There were no differences in CKD 3B-free survival by surgical approach (P = 0.23) or urinary diversion (P = 0.09). 64% of patients experienced renal function decline with a median time of 2.4 years (P 0.23). Predictors of CKD were pathologic T3 disease or greater (HR: 1.77, P = 0.01), ureteroenteric anastomotic stricture (HR: 2.80, P < 0.001), preoperative CKD Stage 2 (HR: 1.81, P =0.02), and preoperative CKD Stage 3A (HR: 5.56, P < 0.001).

CONCLUSION

Renal function decline is common after RC. Tumor stage, pre-operative eGFR, and ureteral stricture development, not surgical approach, influence renal function decline.

Comparison of Major Complications at 30 and 90 Days Following Radical Cystectomy

OBJECTIVES

To better understand the time-course in which major complications occur after radical cystectomy and to describe associations with complications at 30 and 90 days.

METHODS

A database of radical cystectomy cases was queried for preoperative, perioperative, and postoperative data. Follow-up extended to 90 days postsurgery and included major complications (Clavien III-V). Early (30-day) and late (90-day) complication rates were compared via McNemar's test, and patient characteristics were compared across complication time groups by one-way ANOVA or Fisher's exact tests. Multinomial logistic regression was used to explore associations between patient characteristics and complication timing.

RESULTS

Of 969 patients undergoing radical cystectomy, 210/969 (21.7%) experienced a complication within 90 days. The rate of major complication significantly differed at 30 and 90 days (14.4% [conflict of interest (CI): 12.4%-16.9%] vs 21.7% [CI: 19.2%-24.4%] respectively, P ≤.0001). Chronic obstructive pulmonary disease (COPD) (P = .03), Charlson Comorbidity Index (P = .02), and Indiana pouch diversion (P = .002) were significant predictors of early complication. Diabetes was the strongest predictor for late complication (OR: 2.42; P = 0.01). Diabetes was also a significant predictor for late genitourinary complications (OR 3.39; P = .01), and smoking history was a significant predictor for late infectious complications (OR 3.61; P = .01).

CONCLUSION

We identified a significant number of complications occurring after 30 days postcystectomy, including the majority of deaths and genitourinary complications. These findings suggest that assessment of complications exclusively at 30 days would fail to capture a large proportion of major complications and deaths. Understanding the time-course of complications postcystectomy will serve to better inform design of future outcome studies.

The effect of partial nephrectomy on blood pressure in patients with solitary kidney

PURPOSE

To determine the effect of partial nephrectomy (PN) in the solitary kidney on systolic and diastolic blood pressures (SBP and DBP, respectively), and use of antihypertensive medications.

METHODS

We performed a retrospective cohort study of solitary kidney patients who underwent PN for kidney cancer from 1999-2015. Primary outcomes evaluated were blood pressure (BP) and antihypertensive medication changes from baseline up to 5 years postoperatively. Using a multivariable mixed-effects model to account for repeated measurements, we evaluated the effect of PN on the outcome measurements while controlling for baseline patient, pathologic, and perioperative characteristics.

RESULTS

292 patients who underwent PN on solitary kidneys met inclusion criteria (median [range] age, 63 [24-84] years; 179 men [61%]). SBP decreased immediately postoperatively (- 1.7 mmHg [- 2.6, - 0.7], p < 0.001), and further decreased by 0.04 mmHg per year (p = 0.01) postoperatively, for a total change of - 1.9 [- 3.9, 0.2] mmHg at 5 years (p = 0.01). DBP decreased immediately postoperatively (- 2.2 mmHg [- 2.7, - 1.7], p < 0.001), and then rebounded by 0.37 mmHg per year (p = 0.003) postoperatively, for a total change of - 0.4 [- 1.5, 0.7] mmHg at 5 years (p = 0.003). Antihypertensive medication use increased at 5 years (0.35 more medications per patient, p < 0.001).

CONCLUSIONS

Our results suggest a minimal change in BP after PN, although patients increased antihypertensive medication use. This data suggests damage to renal parenchyma or hilar nerves during PN did not significantly impact BP regulation in our cohort.

Robotic radical cystectomy with intracorporeal urinary diversion: beyond the initial experience

Robotic assisted radical cystectomy (RARC) has gained popularity within minimally-invasive urologic surgery, and has been shown to be a safe procedure with similar oncologic outcomes when compared to the conventional open standard. While initial RARC feasibility and outcomes studies were performed with extracorporeal urinary diversion, intracorporeal urinary diversion (ICUD) is becoming increasingly utilized. Reported benefits of an intracorporeal approach include decreased blood loss and a lower incidence of ureteral strictures. While ICUD is technically challenging, many have overcome the learning curve associated with this procedure via a mentorship model and a dedicated operative team. Techniques vary between institutions, and ileal conduit, continent cutaneous and orthotopic continent (neobladder) diversions have all been performed. Herein, we describe the learning curve, technical points, and unique complications associated with ICUD.

Blood myeloid derived suppressor cells (MDSC) in metastatic urothelial carcinoma (mUC) are correlated with neutrophil-to-lymphocyte ratio (NLR) and overall survival (OS)

436

Background: MDSC have been linked to the chronic inflammatory microenvironment of tumor cells and pathologic outcomes in UC patients (pts) undergoing cystectomy. NLR is an established inflammatory biomarker with prognostic properties in mUC. We hypothesized that MDSCs correlate with NLR and OS in mUC. Methods: MDSCs were measured in blood samples from mUC patients by fresh unfractionated whole blood (WB) and peripheral blood mononuclear cells (PBMC). MDSCs were identified by flow cytometry in WB and defined as LinloCD33+/HLADR- (Total MDSC). MDSC subsets were defined as polymorphonuclear (PMN-MDSC: CD15+/CD14-), monocytic (M-MDSC: CD15-/CD14+), and uncommitted (UC-MDSC: CD15-/CD14-). MDSC populations were presented as % of live nucleated blood cells from PB and absolute numbers from WB. Spearman’s correlation assessed correlations between MDSC & NLR. Kaplan Meier curves and log rank test estimated OS from the time of MDSC collection to last follow up or date of death. Results: Of 79 pts, 77% were men and 42% were never smokers with a median age of 69 (31-83). Overall, 71% had pure UC and 81% had lower tract UC. Prior therapies include intravesical therapy (22%), neoadjuvant chemotherapy (31%), and cystectomy/nephroureterectomy (61%). Median follow up was 12 months (range: 0.6-36.5). PMN-MDSC was the predominant subset in WB and PBMC. There was significant correlation between individual MDSC subsets in WB and PBMC (p≤0.001). Negative correlation was noted between NLR and WB UC-MDSC:PMN-MDSC ratios (rho = -0.27, p = 0.03), as well as NLR and PB UC-MDSC:PMN-MDSC (rho = -0.28, p = 0.02). Median survival was 17.7 months (95% CI: 11.0-NA months). Overall 1-yr and 3-yr survival were 0.60 (95% CI: 0.49-0.73) and 0.15 (95% CI: 0.03-0.67), respectively. Higher WB UC-MDSC levels were associated with shorter OS (HR 2.85, 95% CI: 1.43-5.65, p = 0.003). Conclusions: Specific MDSC subsets correlate with NLR. Higher WB UC-MDSC levels have negative prognostic roles for OS. Given the feasibility of serial blood draws, dynamic assessment of MDSC over time and further validation with longer follow up are needed.

Identification of gene expression determinants of radiosensitivity in bladder cancer (BCa) cell lines

470

Background: Trimodality therapy with TURBT followed by concurrent chemoradiation is an alternative to cystectomy in selected patients with muscle invasive BCa. Identifying genetic determinants of radiation response may help select patient for organ-sparing treatments with curative intent. Methods: Molecular characterization of 20 cell lines was previously performed, including mutation analysis, CNA (high density SNP arrays) and gene expression (RNAseq). Cell line identity was authenticated by genomic fingerprinting. We performed colony forming assays (CFA) and cumulative survival was quantified using the area under the cell survival curve (AUC, range 0-8Gy) to create a radiosensitivity index. Pre and post-radiation proliferative capacity was determined by cell titer glo (CTG) assay. Gene (R v3.5.1) and network (Ingenuity Pathyway Analysis) level expression differences were determined as a function of AUC to identify biologically relevant associations with radiation response. Results: Of 20 cell lines (7 basal, 13 luminal subtype), both CFA and CTG data was successfully obtained for 13 cell lines (6 basal, 7 luminal) treated with high dose rate (HDR) radiation. AUCs for the colony forming assay (CFA) survival curves ranged 1.79-3.27. RNAseq identified 18,634 unique transcripts mapping to distinct loci and 196 genes were identified with AUC correlation p values <0.01 (FDR <0.5, mean FPKM>0.5). These genes were strongly enriched for membership in the peroxisome proliferator (PPAR) pathway (IPA, p = 9.40E-03) and STAT3 pathway (IPA, p = 1.56E-3). Validation studies confirmed PPARγ, ICAM2, JAK3, IL1B, OAS1 and OAS2 genes to be associated with differential response to radiation, with expression upregulated in radio-resistant cells. A basal subtype was strongly associated with a radiosensitive phenotype (Chi-Squared χ2 p=0.0083). Conclusions: BCa radio-sensitivity was associated with baseline gene expression differences in vitro. The basal subtype and repression of either the PPAR or STAT3 pathways predicted increased radiosensitivity. This study nominates candidate biomarkers for mechanistic studies and clinical validation in BCa.

Correlation of myeloid-derived suppressor cells (MDSC) with pathologic complete response (pCR), recurrence free survival (RFS), and overall survival (OS) in patients with urothelial carcinoma (UC) undergoing cystectomy

437

Background: MDSCs play an important role in maintaining a tumor immunosuppressive microenvironment. The association of circulating levels of MDSCs with pCR (pT0N0) and outcomes was investigated in patients (pts) with non-metastatic UC undergoing cystectomy. Methods: Peripheral blood samples from pts with non-metastatic UC was collected. MDSCs were measured in freshly purified peripheral blood mononuclear cells, using flow cytometry. Total (T) MDSC was defined as CD33+/HLADR-. T-MDSC subtypes were polymorphonuclear (PMN-MDSC: CD15+/CD14-), monocytic (M-MDSC: CD15-/CD14+], and uncommitted (UC-MDSC: CD15-/CD14-]. MDSC populations were presented as % of live nucleated blood cells. Wilcoxon rank sum test was used to compare MDSCs between pCR groups. Kaplan-Meier and log-rank test were used to analyze RFS and OS. Results: MDSC data were available for 124 pts (106 male, 18 female), median age 68, 28 (23%) never smokers, 93 (75%) pure UC. Thirty four pts (27%) received intravesical BCG; 49 (39%) received neoadjuvant chemotherapy (NAC); 22 (19%) had pCR (pT0N0) following surgery. PMN-MDSC was the dominant subtype (42%) and frequency of UC-MDSC and M-MDSC was 40% and 17%, respectively. Circulating levels of T-MDSC and PMN-MDSC were significantly lower in pCR patients than those in non-pCR patients (Table). Sixteen deaths were observed and 21 pts recurred after surgery. The median follow-up time of patients alive was 18.7 months (range 0.3-42.4). The median OS or RFS of all patients was not reached. One-year and two-year OS rates were 94% and 83%, respectively. One-year and two-year RFS rates were 82% and 69%, respectively. There was no association between MDSC subtypes with OS or RFS. Conclusions: Total- and PMN-MDSC subtypes in blood were significantly correlated with pCR in pts with non-metastatic UC who undergo cystectomy. The relatively short follow-up may impact the association with RFS and OS; additional follow-up is needed. [Table: see text]

Expanding the Indications of Robotic Partial Nephrectomy for Highly Complex Renal Tumors: Urologists' Perception of the Impact of Hyperaccuracy Three-Dimensional Reconstruction

OBJECTIVES

To assess the role of three-dimensional (3D) reconstruction in aiding preoperative planning for highly complex renal tumors amenable to robotic partial nephrectomy (RPN).

MATERIALS AND METHODS

Computed tomography (CT) scans and respective 3D reconstructions of 20 highly complex renal tumors were displayed to the attendees/urologists of the 6th Techno-Urology Meeting ( www.technourologymeeting.com ). These 20 cases had already undergone RPN performed by a single experienced surgeon. The attendees were asked to watch the videos of the CT scans first, and then the respective 3D reconstructions of 5 of the 20 cases who were randomly selected. A purpose-built questionnaire collected responders' surgical experience and surgical indication (RPN versus nephrectomy) after viewing the CT scan and the respective 3D reconstructions.

RESULTS

Twenty expert urologists, 27 young urologists, and 61 residents (total = 108) participated in the study. Five hundred forty-two views of the cases were obtained. Based on CT scans, RPN was indicated in 256 cases (47.2%). After viewing the respective 3D reconstructions, in 148 cases the responders changed their idea: indication to RPN raised in 404 cases (74.5%) (P < .001). The opinions changed regardless of the surgical experience.

CONCLUSIONS

The findings of this study are encouraging, and they might represent a significant step toward the validation of the use of 3D reconstruction for surgical planning in patients undergoing robotic kidney surgery. The use of this technology might translate into a larger adoption of nephron-sparing approach. Further investigation in this area is warranted to corroborate these findings.

Transcriptomic and Protein Analysis of Small-cell Bladder Cancer (SCBC) Identifies Prognostic Biomarkers and DLL3 as a Relevant Therapeutic Target

PURPOSE

Transcriptomic profiling can shed light on the biology of small-cell bladder cancer (SCBC), nominating biomarkers, and novel therapeutic targets.

EXPERIMENTAL DESIGN

Sixty-three patients with SCBC had small-cell histology confirmed and quantified by a genitourinary pathologist. Gene expression profiling was performed for 39 primary tumor samples, 1 metastatic sample, and 6 adjacent normal urothelium samples (46 total) from the same cohort. Protein levels of differentially expressed therapeutic targets, DLL3 and PDL1, and also CD56 and ASCL1, were confirmed by IHC. A SCBC PDX model was utilized to assess in vivo efficacy of DLL3-targeting antibody-drug conjugate (ADC).

RESULTS

Unsupervised hierarchical clustering of 46 samples produced 4 clusters that correlated with clinical phenotypes. Patients whose tumors had the most "normal-like" pattern of gene expression had longer overall survival (OS) compared with the other 3 clusters while patients with the most "metastasis-like" pattern had the shortest OS (P = 0.047). Expression of DLL3, PDL1, ASCL1, and CD56 was confirmed by IHC in 68%, 30%, 52%, and 81% of tissue samples, respectively. In a multivariate analysis, DLL3 protein expression on >10% and CD56 expression on >30% of tumor cells were both prognostic of shorter OS (P = 0.03 each). A DLL3-targeting ADC showed durable antitumor efficacy in a SCBC PDX model.

CONCLUSIONS

Gene expression patterns in SCBC are associated with distinct clinical phenotypes ranging from more indolent to aggressive disease. Overexpression of DLL3 mRNA and protein is common in SCBC and correlates with shorter OS. A DLL3-targeted ADC demonstrated in vivo efficacy superior to chemotherapy in a PDX model of SCBC.

The association between HSD3B1 genotype and steroid metabolism in normal and prostate cancer (PCa) tissue

TPS155

Background: The common germline variant HSD3B1(1245C) encodes for a gain-of-function in 3βHSD1 which is associated with a shorter duration of response to androgen deprivation therapy (ADT) and more rapid disease progression to castration resistant PCa (CRPC) as shown previously in 5 independent cohorts. Therefore, evaluating the effect of such genotype variation on the level of steroid metabolites and the intratumoral dihydrotestosterone (DHT) concentration in benign and tumor tissue of men on ADT is of significant importance. We hypothesize that patients with homozygous HSD3B1 (1245C) genotype (HZ) will have a sustained androgen synthesis from extragonadal precursor steroids and higher concentrations of DHT compared to patients with wild-type HSD3B1 (1245A) (WT) inheritance in the context of testosterone suppression. In addition, it is expected that heterozygous HSD3B1 (1245C) patients (HTZ) will have intermediate levels of DHT. We also hypothesize that treatment with androgen receptor (AR) antagonist (apalutamide) will reverse the effects of elevated DHT on AR signaling in benign and malignant prostate tissue. Methods: In this Phase II trial (NCT02770391), men with newly diagnosed intermediate or high-risk PCa (GS ≥ 4+3, ≥cT2b, or PSA ≥ 10) who are scheduled to undergo radical prostatectomy (RP) will be enrolled into 3 groups based on their HSD3B1 genotype. All pts will receive one dose of 7.5 mg leuprolide injection and apalutamide 240 mg/day orally for 28 ± 3 days prior to RP. DHT and 7 other androgens (including testosterone, Dehydroepiandrosterone, Androstenedione) will be evaluated in the normal and malignant prostate tissue as well as serum samples obtained at the time of RP. AR regulated genes expression (including PSA, FKBP5, TMPRSS2) will be compared across 3 genotypes. A sample size of 57 pts (WT = 30, HTZ = 15, HZ = 12) will allow a statistical power of > 80% (with two-sided α = 0.05) to detect a 4-fold trend in DHT concentrations in the resected prostate tissue (primary endpoint) as well as similar trend in other androgens (secondary endpoint). As of Oct 2017, 16 of planned 57 pts have been enrolled. Clinical trial information: NCT02770391.

Clinicopathologic factors, treatment patterns, and outcomes in micropapillary urothelial carcinoma (UC)

439

Background: Micropapillary UC remains rare yet with an aggressive phenotype. Limited data exists regarding the optimal management of this variant in the contemporary era. Methods: A retrospective analysis was performed to identity patients (pts) with micropapillary UC at the Cleveland Clinic (1997-2017). Demographic, clinico-pathological, treatment regimens, and clinical outcomes, e.g. progression-free and overall survival (PFS and OS) data were collected. Results: A total of 102 pts with median age 70.5 (46-90) at diagnosis, 84%, men, 17% never smokers were identified. Stage at diagnosis for 68 pts with available data was T1 in 29, T2 in 36, T3 in 1, T4 in 2, N+ in 5, and M+ in 4 pts, respectively. Twelve pts were initially treated with intravesical therapy for NMIBC with 58% progressing to higher stage. Overall, 81% of pts had cystectomy; of those 19% had neoadjuvant chemotherapy (NAC; 81% cisplatin-based, median 3 cycles), 21 pts received adjuvant chemotherapy and 3 pts adjuvant radiation. Of 12 pts with available data, 4 had down-staging with NAC with 1 pCR. Pathologic stage was 0is, I, II, III, IV in 4%, 10%, 9%, 9%, and 67% respectively. Overall, 61 pts had recurrent or de-novo metastatic disease (most nodal/local-regional recurrence). For patients with recurrence post-surgery (n = 31), 35% received systemic chemotherapy, 16% had salvage surgery, 10% had salvage radiation, 19% had best supportive care, and the rest were lost to follow-up or refused treatment. The most common 1st-line regimen included platinum-doublet (46%), other combinations (23%), single-agent (23%) and immune checkpoint inhibitors (8%). Overall response (CR/PR) to 1st-line treatment was 38% and median PFS was 8 months (95%CI 0-16.4). Overall, 29 pts died with recurrent/metastatic disease with a median OS (from time of diagnosis) of 39.3 months (95%CI 28.4-50.2) Median OS (from time of diagnosis) for pts treated with cystectomy was 47.1 months (95%CI 23.9-50.2). Conclusions: Micropapillary UC was associated with advanced pathologic stage at cystectomy and limited use of NAC. Responses were noted with NAC and 1st line systemic treatment. Further validation can assist in prognostication and selection/stratification in future trials.

Adjuvant enzalutamide (Enza) for men with non-metastatic high-risk prostate cancer (HRPCa) after radical prostatectomy (RP)

88

Background: Management of HRPCa is a clinical challenge. Novel AR inhibitors could potentially impact outcome in HRPCa men following RP. We conducted a phase II study evaluating the efficacy/safety of Enza in men with HRPCa following RP. Methods: HRPCa pts (≥pT3a, GS≥8, iPSA ≥20 ng/mL, +ve lymph nodes (LN), or ≥35% chance of biochemical recurrence (BCR) at 5 yrs based on MSKCC’s nomogram) with undetectable PSA within 3 months from RP were eligible. Enza 160mg PO daily was given in 28-day cycles until disease progression, intolerability, consent withdrawal, or study completion at 24 months. Accrual goal was N=40 to provide 80% power to detect a 75% decrease in the risk of BCR from historical 55% rate. BCR was defined as PSA ≥0.2ng/mL on 2 consecutive lab results or any PSA rise that resulted in subsequent therapy. Results: 42 men enrolled. Median age 59 (range 43-70), based on biopsy 45% were GS7; 36% GS8, 19% GS9. 76% men had cT1, 24% cT2, median iPSA was 8.2 (range 2-77). On prostatectomy pathology: 50% had pT3b; 52% +ve margins; 50% SVI; 24% had +LN. 37 (88%) pts completed 24 planned cycles. Of the 5 pts who did not complete all cycles, 3 withdrew consent for toxicity (2 had G3 fatigue, 1 had G3 fatigue and arthralgias/myalgias), 1 had rising PSA requiring subsequent therapy, and 1 had financial concerns. With median follow-up of 31 months (range 2.5-44.5), 37 (88%) pts remain free of BCR. Of the 5 pts who developed BCR, 4 completed all 24 months on therapy. Median time to BCR was 31 months (range 13-40). Most common adverse events (AE) are listed (Table). Conclusions: Adjuvant Enza in men with HRPCa following RP is safe and relatively well-tolerated. Long-term safety, efficacy, and genomic correlations (including tumor RNA expression) are ongoing. Clinical trial information: NCT01927627. [Table: see text]

Impact of neoadjuvant chemotherapy on pathologic outcomes in patients with upper tract urothelial carcinoma undergoing extirpative surgery

457

Background: Neoadjuvant chemotherapy (NAC) is infrequently administered to patients with upper tract urothelial carcinoma (UTUC) undergoing radical nephroureterectomy or segmental ureterectomy and its impact on pathologic outcomes unclear. We examine pathologic outcomes in patients with UTUC receiving NAC before extirpative surgery using a population-based cancer registry. Methods: Patients who underwent extirpative surgery for UTUC from 2006-2014 were identified from the National Cancer Database. Among patients with available clinicopathologic data, the incidence of pathologic down-staging, defined as a lesser pathologic compared to clinical stage, was compared between patients who did and did not receive NAC. A multivariable model was developed to identify predictors of pathologic down-staging. Results: 7,244 patients were identified with non-metastatic UTUC who underwent extirpative surgery in the study period. 260 patients (3.6%) received NAC, with the use of NAC increasing over time from 2.0% patients in 2006 to 7.1% of patients in 2014 (linear trend p < 0.001). Clinical and pathologic staging data were available for 119 and 2904 patients who did and did not receive NAC, respectively. Thirty patients (25.2%) who received NAC experienced pathologic down-staging, compared to 52 patients (1.8%) who did not receive NAC (p < 0.0001). On multivariable analysis, NAC was associated with a higher likelihood of pathologic down-staging (OR 10.2, 95% CI 5.4-19.3). Additional predictors of pathologic down-staging include a higher clinical T stage (p = 0.001) and African-American race (OR 2.7, 95% CI 1.1-6.6). Compared to renal pelvis UTUC, ureteral UTUC was associated with a similar likelihood of pathologic down-staging (OR 1.5, 95% CI 0.9-2.5). Conclusions: NAC is infrequently used among patients with UTUC undergoing extirpative surgery. A higher incidence of pathologic down-staging was observed among patients receiving NAC. These findings suggest clinical benefit of NAC with respect to pathologic outcomes in patients with UTUC and may help guide selection of patients for NAC prior to radical surgery until data from prospective studies becomes available.

Cisplatin-based neoadjuvant chemotherapy (NAC) for muscle-invasive bladder cancer (MIBC) in patients (pts) with impaired renal function

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Background: Cisplatin-based NAC followed by radical cystectomy is the standard of care in MIBC but many pts are cisplatin-unfit. Data in pts with low glomerular filtration rate (GFR) who receive cisplatin-based NAC is limited. Methods: A retrospective analysis of pts who received cisplatin-based NAC at Cleveland Clinic (2005-2016) was conducted. Pts with pre-NAC GFR < 60 ml/min by either CG or MDRD formula (low GFR; N = 30) were compared to pts with GFR ≥60 (normal GFR; N = 94) in terms of NAC tolerability and outcomes including pathologic complete (pCR, pT0N0) and partial response (pPR, < pT2N0). A secondary analysis compared 3 groups of pts: GFR < 50ml/min (N = 10), GFR 50-59 ml/min (N = 20), and GFR ≥60 (N = 94). Results: Low GFR pts were older (median age 71 vs 65, p < 0.001) and had higher rates of hydronephrosis (33% vs 15%, p = 0.03). ECOG PS, other demographic and TURBT features (stage, LVI, CIS) did not differ significantly. Low GFR pts were more likely to receive gemcitabine/cisplatin (83% vs 71%, p = 0.04) and get split-dose cisplatin (38% vs 16%, p = 0.02). Split-dose cisplatin use in low GFR pts did not impact NAC tolerability or outcomes. NAC cycles completed (median 3 per group) were comparable, and most low GFR pts (70%) completed intended NAC regimen. Low GFR pts were more likely to have early NAC discontinuation (30% vs 13%, p = 0.03) and NAC modification (delay, dose reduction, discontinuation) (66% vs 40%, p = 0.02). No differences were seen in cystectomy completion rate (93% per group), time to cystectomy, length of stay, surgical complications, and GFR change from baseline. Combined pCR/pPR was higher in normal GFR group (54% vs 25%, p = 0.01). Among pts with very low GFR ( < 50 ml/min), 60% completed intended NAC regimen and 70% had NAC modification. Rates of pCR and pPR were low: 0% and 12%, respectively. Conclusions: Low GFR pts were older, had more NAC discontinuations/modifications and lower pCR/pPR rate, but most completed planned NAC cycles. Relative to normal GFR pts, low GFR pts were not prevented or delayed in getting cystectomy, and had comparable impact of NAC on GFR. For carefully selected pts with GFR < 60 ml/min, cisplatin-based NAC is a treatment option, consistent with prior data.

Robotic Total Pelvic Exenteration With Intracorporeal Sigmoid Conduit and Colostomy: Step-by-Step Technique

OBJECTIVE

To describe our technique for robotic total pelvic exenteration with intracorporeal sigmoid conduit and colostomy using the da Vinci Si robot.

METHODS

Three 8-mm robotic ports and two 12-mm laparoscopic ports are placed in a "W" configuration, approximately 2-3 cm more cephalad than for radical prostatectomy (Fig. 1). The robot is docked between the legs with the patient in steep Trendelenburg. The ureters are dissected out from the iliac vessels to the rectovesical pouch, where they are clipped and transected. The sigmoid colon is stapled across at the rectosigmoid junction and reflected into the abdomen. A posterior plane is developed below the rectum (Fig. 2A), if space allows, or through the rectum. The endopelvic fascia is exposed and incised bilaterally. After sequentially controlling the bladder and prostatic pedicles (Fig. 2B) using the Harmonic scalpel, the urethra is transected at the prostatic apex, and the anterior rectal wall is incised (Fig. 2C). Any remaining attachments are divided, the rectal remnant is excised, and the specimen is bagged and extracted (Fig. 2D). Adjacent segments of left and sigmoid colon are harvested for the conduit and colostomy, avoiding a bowel anastomosis. The ureters are anastomosed to the conduit, maintaining separation between the gastrointestinal and the urinary systems. The conduit and left end colostomy are matured (Fig. 3). The technique is performed entirely intracorporeally with specimen extraction through the anus, avoiding a large open incision.

RESULTS

We present the case of a high-functioning (Eastern Cooperative Oncology Group performance status 1) 73-year-old man with metastatic castrate-resistant prostate cancer following failed primary brachytherapy. Despite a good systemic response to chemotherapy and complete androgen blockade, his prostate-specific antigen level continued to rise (to 33 ng/mL) because of an enlarging prostatic pelvic mass. He suffered from progressive local symptoms, including intractable pelvic pain, obstructive uropathy, and impending rectal obstruction. The indication for pelvic exenteration was local palliation. Total robotic time was 5.4 hours. The perioperative course was complicated by disseminated intravascular coagulation secondary to metastatic prostate cancer, which resulted in a transient ischemic attack. The disseminated intravascular coagulation resolved with blood product transfusion, and the patient recovered well without permanent disability. In-patient length of stay was 8 days. Complete local palliation was achieved until the patient's death from prostate cancer 5 months later.

CONCLUSION

We demonstrate our step-by-step technique for robotic total pelvic exenteration with intracorporeal sigmoid conduit.

Serial measurements of myeloid derived suppressor cells (MDSC) in metastatic urothelial carcinoma (mUC) patients (pts) treated with immune checkpoint inhibitors (CI)

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Background: MDSC are a heterogeneous population of immunosuppressive cells with potentially predictive implications in UC pts receiving CI. We hypothesized that MDSC populations may change after CI exposure. Methods: Serial peripheral blood samples were collected from mUC pts treated with CI. MDSC were measured in fresh unfractionated whole blood (WB) and in peripheral blood mononuclear cells (PBMC). MDSC were identified by flow cytometry in WB and defined as LinloCD33+/HLADR- [(T)otal MDSC]. MDSC subsets were defined as (G)ranulocytic (CD15+CD14-), (M)onocytic (CD15-CD14+), (I)mmature (CD15-CD14-), or CD11b+. MDSC populations were presented as % of live nucleated blood cells and as absolute numbers from WB. The Wilcoxon signed rank and rank sum tests were used to assess changes in MDSC populations while on CI. Results: 17 pts treated with CI (9 atezolizumab [A], 8 pembrolizumab [P]) had ≥ 2 MDSC samples for analysis. Median age at diagnosis was 71 (46-81), 12 men, 29% never smokers; 53% / 29% / 18% ECOG PS 0/1/2 and 59% visceral metastasis at the time of 1st sample collection. 10 pts received CI as 1st line therapy (Tx) in metastatic setting; 7 pts received chemotherapy as 1st-line Tx for mUC (6 platinum-based, 1 docetaxel) and CI as 2nd-line Tx. In 16 pts with samples before 1stdose, there was a relative decrease (median 36.3%, range -59.7 to +21.2) in PBMC % I-MDSCs between 1st and 2nd samples (p=0.06). Interestingly, PBMC %M-MDSC and %I-MDSC tended to increase compared to baseline in pts treated with P, while they tended to decrease in pts treated with A (Table). Conclusions: In this cohort of pts with mUC treated with CIs,MDSC changes differed based on CI (anti-PDL1 or anti-PD1). Further study in larger cohort with various prior Tx lines and longer follow up as well as correlations with Tx response, toxicity and outcomes are ongoing. [Table: see text]

Hilar Parenchymal Oversew: a novel technique for robotic partial nephrectomy hilar tumor renorrhaphy

Introduction

A renorrhaphy technique which is effective for hemostasis but does not place undue tension on the branch vessels of the renal sinus remains one of the challenging steps after hilar tumor resection during robotic partial nephrectomy (RPN). The published V-hilar suture (VHS) technique is one option for reconstruction after an RPN involving the hilum. The objective of this video is to show a novel renorrhaphy technique, Hilar Parenchymal Oversew that has been effective for such cases.

Materials and Methods

We present two cases of RPN for renal hilar tumors. The first case depicts use of the VHS renorrhaphy technique for a tumor that abuts the renal hilum along 20% of its diameter. The second case demonstrates tumor resection and reconstruction for a tumor that has >50% involvement of the hilum along its diameter. After tumor resection, individual sinus vessels can be selectively oversewn with 2-0 Vicryl suture on SH needle. The remaining exposed parenchyma is controlled using the Hilar Parenchymal Oversew technique with a #0 Vicryl on CT-1 needle.

Results

For the Hilar Parenchymal Oversew surgery operative time was 225 min, estimated blood loss was 140 ml, warm ischemia time was 19 minutes, and there were no intraoperative complications. Pathology was consistent with clear cell renal cancer with negative margins.

Conclusion

Robotic partial nephrectomy with the Hilar Parenchymal Oversew technique is a good alternative to VHS renorrhaphy in the management of renal hilar tumors “bulging” into the renal sinus with >50% of the tumor diameter abutting the hilum.