Explainable Machine Learning Model to Preoperatively Predict Postoperative Complications in Inpatients With Cancer Undergoing Major Operations

PURPOSE

Preoperative prediction of postoperative complications (PCs) in inpatients with cancer is challenging. We developed an explainable machine learning (ML) model to predict PCs in a heterogenous population of inpatients with cancer undergoing same-hospitalization major operations.

METHODS

Consecutive inpatients who underwent same-hospitalization operations from December 2017 to June 2021 at a single institution were retrospectively reviewed. The ML model was developed and tested using electronic health record (EHR) data to predict 30-day PCs for patients with Clavien-Dindo grade 3 or higher (CD 3+) per the CD classification system. Model performance was assessed using area under the receiver operating characteristic curve (AUROC), area under the precision recall curve (AUPRC), and calibration plots. Model explanation was performed using the Shapley additive explanations (SHAP) method at cohort and individual operation levels.

RESULTS

A total of 988 operations in 827 inpatients were included. The ML model was trained using 788 operations and tested using a holdout set of 200 operations. The CD 3+ complication rates were 28.6% and 27.5% in the training and holdout test sets, respectively. Training and holdout test sets' model performance in predicting CD 3+ complications yielded an AUROC of 0.77 and 0.73 and an AUPRC of 0.56 and 0.52, respectively. Calibration plots demonstrated good reliability. The SHAP method identified features and the contributions of the features to the risk of PCs.

CONCLUSION

We trained and tested an explainable ML model to predict the risk of developing PCs in patients with cancer. Using patient-specific EHR data, the ML model accurately discriminated the risk of developing CD 3+ complications and displayed top features at the individual operation and cohort level.

Targeting Alpha-Ketoglutarate Disruption Overcomes Immunoevasion and Improves PD-1 Blockade Immunotherapy in Renal Cell Carcinoma

The Warburg effect-related metabolic dysfunction of the tricarboxylic acid (TCA) cycle has emerged as a hallmark of various solid tumors, particularly renal cell carcinoma (RCC). RCC is characterized by high immune infiltration and thus recommended for immunotherapeutic interventions at an advanced stage in clinical guidelines. Nevertheless, limited benefits of immunotherapy have prompted investigations into underlying mechanisms, leading to the proposal of metabolic dysregulation-induced immunoevasion as a crucial contributor. In this study, a significant decrease is found in the abundance of alpha-ketoglutarate (αKG), a crucial intermediate metabolite in the TCA cycle, which is correlated with higher grades and a worse prognosis in clinical RCC samples. Elevated levels of αKG promote major histocompatibility complex-I (MHC-I) antigen processing and presentation, as well as the expression of β2-microglobulin (B2M). While αKG modulates broad-spectrum demethylation activities of histone, the transcriptional upregulation of B2M is dependent on the demethylation of H3K4me1 in its promoter region. Furthermore, the combination of αKG supplementation and PD-1 blockade leads to improved therapeutic efficacy and prolongs survival in murine models when compared to monotherapy. Overall, the findings elucidate the mechanisms of immune evasion in anti-tumor immunotherapies and suggest a potential combinatorial treatment strategy in RCC.

NCCN Guidelines® Insights: Prostate Cancer Early Detection, Version 1.2023

The NCCN Guidelines for Prostate Cancer Early Detection provide recommendations for individuals with a prostate who opt to participate in an early detection program after receiving the appropriate counseling on the pros and cons. These NCCN Guidelines Insights provide a summary of recent updates to the NCCN Guidelines with regard to the testing protocol, use of multiparametric MRI, and management of negative biopsy results to optimize the detection of clinically significant prostate cancer and minimize the detection of indolent disease.

Feasibility of perioperative remote monitoring of patient-generated health data in complex surgical oncology

BACKGROUND

The feasibility of remote perioperative telemonitoring of patient-generated physiologic health data and patient-reported outcomes in a high risk complex general and urologic oncology surgery population is evaluated.

METHODS

Complex general surgical/urologic oncology patients wore a pedometer, completed ePROs (electronic patient-reported outcome surveys) and record their vitals (weight, pulse, pulse oximetry, blood pressure, and temperature) via a telehealth app platform. Feasibility (% adherence) was assessed as the primary outcome measure.

RESULTS

Twenty-one patients with a median age 58 (32-82) years were included. The readmission rate was 33% and the incidence of ≥Grade 3a morbidity was 24%. Adherence to vital sign and ePRO measurements was 95% before surgery, 91% at discharge, and 82%, 68%, and 64% at postdischarge d2, 7, 14, and 30, respectively. There was significant worsening of mobility, self-care and usual daily activity at postdischarge d2 compared to preoperative baseline (p < 0.05). Median daily preoperative steps taken by patients with <Grade 3a versus ≥Grade 3a postoperative morbidity was 6062 versus 4166 (p < 0.05). Of those interviewed, 87% (13/15) viewed vital sign devices as helpful in recovery.

CONCLUSIONS

Telemonitoring is feasible in a general surgical and urologic oncology setting. Future studies will ascertain optimal patient selection, duration, and extent of perioperative monitoring.

MRI-guided focused ultrasound focal therapy for patients with intermediate-risk prostate cancer: a phase 2b, multicentre study

BACKGROUND

Men with grade group 2 or 3 prostate cancer are often considered ineligible for active surveillance; some patients with grade group 2 prostate cancer who are managed with active surveillance will have early disease progression requiring radical therapy. This study aimed to investigate whether MRI-guided focused ultrasound focal therapy can safely reduce treatment burden for patients with localised grade group 2 or 3 intermediate-risk prostate cancer.

METHODS

In this single-arm, multicentre, phase 2b study conducted at eight health-care centres in the USA, we recruited men aged 50 years and older with unilateral, MRI-visible, primary, intermediate-risk, previously untreated prostate adenocarcinoma (prostate-specific antigen ≤20 ng/mL, grade group 2 or 3; tumour classification ≤T2) confirmed on combined biopsy (combining MRI-targeted and systematic biopsies). MRI-guided focused ultrasound energy, sequentially titrated to temperatures sufficient for tissue ablation (about 60-70°C), was delivered to the index lesion and a planned margin of 5 mm or more of normal tissue, using real-time magnetic resonance thermometry for intraoperative monitoring. Co-primary outcomes were oncological outcomes (absence of grade group 2 and higher cancer in the treated area at 6-month and 24-month combined biopsy; when 24-month biopsy data were not available and grade group 2 or higher cancer had occurred in the treated area at 6 months, the 6-month biopsy results were included in the final analysis) and safety (adverse events up to 24 months) in all patients enrolled in the study. This study is registered with ClinicalTrials.gov, NCT01657942, and is no longer recruiting.

FINDINGS

Between May 4, 2017, and Dec 21, 2018, we assessed 194 patients for eligibility and treated 101 patients with MRI-guided focused ultrasound. Median age was 63 years (IQR 58-67) and median concentration of prostate-specific antigen was 5·7 ng/mL (IQR 4·2-7·5). Most cancers were grade group 2 (79 [78%] of 101). At 24 months, 78 (88% [95% CI 79-94]) of 89 men had no evidence of grade group 2 or higher prostate cancer in the treated area. No grade 4 or grade 5 treatment-related adverse events were reported, and only one grade 3 adverse event (urinary tract infection) was reported. There were no treatment-related deaths.

INTERPRETATION

24-month biopsy outcomes show that MRI-guided focused ultrasound focal therapy is safe and effectively treats grade group 2 or 3 prostate cancer. These results support focal therapy for select patients and its use in comparative trials to determine if a tissue-preserving approach is effective in delaying or eliminating the need for radical whole-gland treatment in the long term.

FUNDING

Insightec and the National Cancer Institute.

Genomic analysis and long-term outcomes of a phase 1 clinical trial on cytoreductive radical prostatectomy

Purpose

Approximately 7% of patients with newly diagnosed prostate cancer (PCa) in the US will have have metastatic disease. The dogma that there is no role for surgery in this population has been questioned recently. Here we report long-term outcomes of a phase 1 clinical trial on cytoreductive radical prostatectomy.

Materials and methods

This is a multicenter phase 1 trial. The major inclusion criterion was biopsy proven N1M0 or NxM1a/b PCa. Primary end point was the Clavien-Dindo-based major complication rate. Secondary outcomes were biochemical progression and overall survival. RNA-seq correlative study was conducted in nine select cases as a pilot study.

Results

Final accrual was 32 patients of which 25 and 7 were cNxM1 and cN1M0, respectively. With the median follow-up of 46 months (interquartile range 31.7 - 52.7 months), 25 out of the 32 patients (75%) were alive at the time of last contact. There were three disparate groups based on the oncologic outcome: favorable, intermediate, and poor. In seven men with favorable response, androgen deprivation therapy was switched to intermittent approach and five remain free of any evidence of disease after more than two years off all systemic therapy with the normalization of serum testosterone. Of these five patients, three had M1 disease. Long-term use of one pad or less per day was 80%. RNA-seq analysis revealed an enriched downregulation of tumor necrosis factor (TNF)-α signature in the favorable group.

Conclusion

Overall long-term oncologic outcome of cytoreductive radical prostatectomy was significantly higher than historical results. Importantly, the combination of surgery with systemic therapy may result in a long durable response in a minority of men who present with metastatic PCa.

Prostate Cancer Characteristics and Outcomes after Prostatectomy in Asian-American Men

BACKGROUND

Prostate cancer is the most commonly diagnosed cancer in American men, with striking differences between ethnic groups. Given the potential for lifestyle or genetic variations between subsets of Asian-American men to impact prostate cancer behavior, we sought to define the outcomes after radical prostatectomy among various Asian groups treated at an NCI-designated comprehensive cancer center.

METHODS

The City of Hope IRB-approved prostatectomy database was searched from 2003 to 2015 to identify Asian-American men. Clinical and pathologic features were collected and analyzed for association with biochemical recurrence-free survival and overall survival (OS). Categorical data were evaluated using χ²and Fisher's exact tests. Survival curves were compared between groups using log-rank testing.

RESULTS

Three hundred and eighty-three Asian-American men were included in the dataset. While Asian men as a group had lower BMI than African-American and white men in the database, there was a wide range between ethnic sub-groups. Chinese men more commonly presented with D'Amico low risk disease features (P= .04) compared to other Asian men. Pacific Islander men had the lowest rate of ≥T3 stage and the highest biochemical recurrence-free survival. OS for Chinese men was better than for all Asian patients combined (P= .046). After controlling for D'Amico risk and in multivariate analysis, Chinese men still had improved OS than other Asian men after prostatectomy (P= .03).

CONCLUSIONS

Asian-American men have differing prostate cancer characteristics. Future efforts to delineate and impact upon prostate cancer outcomes should categorize Asian men by subgroup in order to better elucidate biology, lifestyle factors and/or treatment preferences that may contribute to observed differences.

Machine Learning-Based Interpretation and Visualization of Nonlinear Interactions in Prostate Cancer Survival

PURPOSE

Shapley additive explanation (SHAP) values represent a unified approach to interpreting predictions made by complex machine learning (ML) models, with superior consistency and accuracy compared with prior methods. We describe a novel application of SHAP values to the prediction of mortality risk in prostate cancer.

METHODS

Patients with nonmetastatic, node-negative prostate cancer, diagnosed between 2004 and 2015, were identified using the National Cancer Database. Model features were specified a priori: age, prostate-specific antigen (PSA), Gleason score, percent positive cores (PPC), comorbidity score, and clinical T stage. We trained a gradient-boosted tree model and applied SHAP values to model predictions. Open-source libraries in Python 3.7 were used for all analyses.

RESULTS

We identified 372,808 patients meeting the inclusion criteria. When analyzing the interaction between PSA and Gleason score, we demonstrated consistency with the literature using the example of low-PSA, high-Gleason prostate cancer, recently identified as a unique entity with a poor prognosis. When analyzing the PPC-Gleason score interaction, we identified a novel finding of stronger interaction effects in patients with Gleason ≥ 8 disease compared with Gleason 6-7 disease, particularly with PPC ≥ 50%. Subsequent confirmatory linear analyses supported this finding: 5-year overall survival in Gleason ≥ 8 patients was 87.7% with PPC < 50% versus 77.2% with PPC ≥ 50% (P < .001), compared with 89.1% versus 86.0% in Gleason 7 patients (P < .001), with a significant interaction term between PPC ≥ 50% and Gleason ≥ 8 (P < .001).

CONCLUSION

We describe a novel application of SHAP values for modeling and visualizing nonlinear interaction effects in prostate cancer. This ML-based approach is a promising technique with the potential to meaningfully improve risk stratification and staging systems.

Quality of surgical care can impact survival in patients with bladder cancer after robot-assisted radical cystectomy: results from the International Robotic Cystectomy Consortium

Background

Although pathological factors remain the main determinate of survival for patients with bladder cancer, quality of surgical care is crucial for satisfactory outcomes. Using a validated quality score, we investigated the impact of surgical factors on the overall survival (OS), recurrence-free survival (RFS) and disease-specific survival (DSS) in patients with locally advanced and organ-confined disease (OCD). Retrospective review of IRCC database includes 2460 patients from 29 institutions across 11 countries. The final cohort included 1343 patients who underwent RARCs between 2005 and 2016. Patients with locally advanced disease (LAD) (> pT2 and/or N +) were compared with OCD (≤ pT2/N0). Validated Quality Cystectomy Score (QCS) based on four sets of quality metrics was used to compare surgical performance. Kaplan–Meier method was used to compute RFS, CSS and OS rates. Multivariable stepwise logistic regression was used to evaluate variables associated with RFS, DSS and OS.

Results

48% had LAD. When compared to patients with OCD, they received neobladders less frequently (17% vs. 28%, p < 0.001) and experienced higher estimated blood loss (513 vs. 376 ml, p = 0.05). Postoperatively, more patients in the LAD group received adjuvant chemotherapy (24% vs. 4%, p < 0.001) and positive surgical margins (14% vs. 2%, p < 0.001) and had higher 90-day mortality (6% vs. 2%, p < 0.001). On multivariable analysis, female gender, higher QCS score, intracorporeal diversion, pT stage, positive lymph node status and recurrence are considered as predictors of survival. Patients with OCD exhibited better RFS, DSS and OS than patients with LAD. For patients with OCD, higher QCS was associated with improved OS but not RFS or DSS. On the other hand, patients with LAD and higher QCS exhibited higher RFS, DSS and OS when compared to those with lower QCS.

Conclusion

Quality of surgical care can affect disease control and OS in patients with bladder cancer treated with robot-assisted radical cystectomy.

A comparative propensity score-matched analysis of perioperative outcomes of intracorporeal vs extracorporeal urinary diversion after robot-assisted radical cystectomy: results from the International Robotic Cystectomy Consortium

OBJECTIVE

To compare the perioperative outcomes of intracorporeal (ICUD) vs extracorporeal urinary diversion (ECUD) after robot-assisted radical cystectomy (RARC).

PATIENTS AND METHODS

We retrospectively reviewed the prospectively maintained International Robotic Cystectomy Consortium (IRCC) database. A total of 972 patients from 28 institutions who underwent RARC were included. Propensity score matching was used to match patients based on age, gender, body mass index (BMI), American Society of Anesthesiologists Score (ASA) score, Charlson Comorbidity Index (CCI) score, prior radiation and abdominal surgery, receipt of neoadjuvant chemotherapy, and clinical staging. Matched cohorts were compared. Multivariate stepwise logistic and linear regression models were fit to evaluate variables associated with receiving ICUD, operating time, 90-day high-grade complications (Clavien-Dindo Classification Grade ≥III), and 90-day readmissions after RARC.

RESULTS

Utilisation of ICUD increased from 0% in 2005 to 95% in 2018. The ICUD patients had more overall complications (66% vs 58%, P = 0.01) and readmissions (27% vs 17%, P = 0.01), but not high-grade complications (21% vs 24%, P = 0.22). A more recent RC era and ileal conduit diversion were associated with receiving an ICUD. Higher BMI, ASA score ≥3, and receiving a neobladder were associated with longer operating times. Shorter operating time was associated with male gender, older age, ICUD, and centres with a larger annual average RC volume. Longer intensive care unit stay was associated with 90-day high-grade complications. Higher CCI score, prior radiation therapy, neoadjuvant chemotherapy, and ICUD were associated with a higher risk of 90-day readmissions.

CONCLUSIONS

Utilisation of ICUD has increased over the past decade. ICUD was associated with more overall complications and readmissions compared to ECUD, but not high-grade complications.

Readmission and complications after robotic surgery: experience of 10,000 operations at a comprehensive cancer center

Evaluation of safety is of paramount importance with adoption of novel surgical technology. Although robotic surgery has become widely used in oncologic surgery, analysis of safety is lacking in comparison to traditional techniques. Standardized assessment of robotic surgical outcomes and adverse events following oncologic surgery is necessary for quality improvement with innovative technology. Between 2003 and 2016, 10,013 unique robotic operations were performed in 9,858 patients. Our prospectively maintained database was retrospectively reviewed for hospital readmissions and Clavien-Dindo grade ≥ 2 complications within 30 days. Multivariable logistic regression was used to identify predictors of surgical complications and hospital readmissions. Cases were stratified by discipline: genitourinary (n = 8240), gynecologic (n = 857), thoracic (n = 457), gastrointestinal (n = 322), hepatobiliary (n = 60), ear/nose/throat (n = 44) and general (n = 33). Intraoperative complications occurred in 42 surgeries (0.4%). Postoperative complications occurred in 946 patients [9.4%, highest grade 2 (n = 574), 3 (n = 288), 4 (n = 72), 5 (n = 10)]. Most frequent complications were ileus (154, 16.3%), anemia (91, 9.6%), cardiac arrhythmia (62, 6.6%), deep vein thrombosis/pulmonary embolus (47, 5.0%), wound infection (45, 4.8%) and urinary leak (43, 4.5%). 405 patients (4.0%) required readmission. Most common causes for hospital readmission were ileus (44, 10.9%), urinary leak (23, 5.7%), urinary tract infection (23, 5.7%), intra-abdominal abscess/fluid collection (23, 5.7%), and small bowel obstruction (19, 4.7%). On multivariable analysis, longer operative time and older age predicted complications and readmissions (p ≤ 0.02). Robotic-assisted surgery appears a safe for oncologic surgery with acceptable hospital readmission and complication rates. Older age and longer operative time were associated with complications and readmission.

Stereotactic Body Radiation Therapy to the Prostate Bed: Results of a Phase 1 Dose-Escalation Trial

PURPOSE

The primary objectives of this study were to evaluate toxicity of escalating doses of prostate bed stereotactic body radiation therapy and to provide dose recommendations for a phase 2 study.

METHODS AND MATERIALS

Patients with organ-confined, node-negative prostate cancer who had biochemical failure (prostate-specific antigen [PSA] less than 2.0) after prostatectomy were eligible for this phase 1 dose-escalation trial. Doses delivered were 35 Gy, 40 Gy, and 45 Gy in 5 fractions, given every other day. Dose-limiting toxicity (DLT) was defined as Common Terminology Criteria for Adverse Events (version 4.0) grade 3 or higher gastrointestinal or genitourinary (GU) toxicity within 90 days of treatment. Maximum tolerated dose was the highest dose to be tested where fewer than 2 of the patients experienced DLT. Patients completed quality-of-life questionnaires at regular time intervals.

RESULTS

Twenty-six patients completed treatment between October 2013 and December 2017. Three patients received 35 Gy, 8 patients received 40 Gy, and 15 patients received 45 Gy. The median follow-up was 60 months for 35 Gy, 48 months for 40 Gy, and 33 months for 45 Gy. No acute DLT events were observed. Late grade ≥2 and ≥3 gastrointestinal toxicity occurred in 11% and 0%, respectively, and late grade ≥2 and ≥3 GU toxicity occurred in 38% and 15%, respectively. No difference was observed in late GU toxicity between 40 Gy and 45 Gy. Sexual function scores were significantly lower in the patients receiving androgen deprivation therapy (P < .01). In all patients, the crude rate of PSA control (<0.2 ng/mL) was 11 out of 26 (42%).

CONCLUSIONS

Dose escalation to 45 Gy did not result in acute DLT events, had similar rates of late grade 3 toxicity, and did not demonstrate higher rates of PSA control, compared with 40 Gy. While allowing for higher plan heterogeneity, the recommended dose for phase 2 study will be 40 Gy in 5 fractions.

Risk of complications and urinary incontinence following cytoreductive prostatectomy: a multi-institutional study

Emerging evidence has suggested that cytoreductive prostatectomy (CRP) allows superior oncologic control when compared to current standard of care androgen deprivation therapy alone. However, the safety and benefit of cytoreduction in metastatic prostate cancer (mPCa) has not been proven. Therefore, we evaluated the incidence of complications following CRP in men newly diagnosed with mPCa. A total of 68 patients who underwent CRP from 2006 to 2014 at four tertiary surgical centers were compared to 598 men who underwent radical prostatectomy for clinically localized prostate cancer (PCa). Urinary incontinence was defined as the use of any pad. CRP had longer operative times (200 min vs 140 min, P < 0.0001) and higher estimated blood loss (250 ml vs 125 ml, P < 0.0001) compared to the control group. However, both overall (8.82% vs 5.85%) and major complication rates (4.41% vs 2.17%) were comparable between the two groups. Importantly, urinary incontinence rate at 1-year after surgery was significantly higher in the CRP group (57.4% vs 90.8%, P < 0.0001). Univariate logistic analysis showed that the estimated blood loss was the only independent predictor of perioperative complications both in the unadjusted model (OR: 1.18; 95% CI: 1.02–1.37; P = 0.025) and surgery type-adjusted model (OR: 1.17; 95% CI: 1.01–1.36; P = 0.034). In conclusion, CRP is more challenging than radical prostatectomy and associated with a notably higher incidence of urinary incontinence. Nevertheless, CRP is a technically feasible and safe surgery for selecting PCa patients who present with node-positive or bony metastasis when performed by experienced surgeons. A prospective, multi-institutional clinical trial is currently underway to verify this concept.

Robotic Cystectomy-Moving from Innovation to Measurable Impact

Data from an experienced center that randomized patients to open vs robotic cystectomy for urothelial cancer demonstrated locational differences in recurrence. While the study was not powered to detect survival differences, overall, cancer-specific, and recurrence-free survival were similar.

A collaborative surgical approach to upper and lower abdominal cytoreductive surgery in ovarian cancer

BACKGROUND AND OBJECTIVES

Cytoreductive surgery with complete macroscopic resection in patients with ovarian cancer is associated with improved survival. Institutional reports of combined upper and lower abdominal cytoreductive surgery for more advanced disease have described multidisciplinary approaches. We sought to investigate outcomes in patients undergoing cytoreductive surgery in patients with upper and lower abdominal disease at our institution.

METHODS

Patients who underwent cytoreductive surgery for ovarian malignancies from 2008 to 2015 were retrospectively identified from an institutional database. Upper abdominal cytoreduction was defined anatomically as debulking of disease proximal to the ligament of Treitz. Perioperative outcomes were analyzed.

RESULTS

A total of 258 operations were performed, the majority for serous ovarian carcinoma (70%). The gynecologic oncologist was the primary surgeon and often assisted by either a surgical oncology fellow and/or attending. In operations with combined upper and lower abdominal cytoreduction, patients were more likely to have an American society of anesthesiologists physical status classification system (ASA) of 3, peritoneal implants, and liver/spleen metastases. Preoperative chemotherapy and optimal cytoreduction were similar between groups. Perioperative morbidity and mortality were not significantly different between groups.

CONCLUSIONS

A collaborative surgical approach to combined upper and lower abdominal cytoreductive surgery in patients with ovarian cancer should be performed, if needed, to achieve an optimal cytoreduction.

Biochemical recurrence after robot-assisted extended pelvic lymphadenectomy for prostate cancer

INTRODUCTION

Extended lymph node dissection (ELND) compared to limited lymph node dissection (LLND) at time of prostatectomy improves staging and lymph node (LN) yield. The effect on biochemical recurrence (BCR) and survival is less well understood. We sought to evaluate the benefit of robotic ELND and LLND with respect to BCR.

MATERIALS AND METHODS

Between 2008-2012, 584 consecutive men with intermediate or high risk clinically localized adenocarcinoma of the prostate underwent robotic assisted radical prostatectomy (RARP) with concomitant LLND (n = 326) or ELND (n = 258). Survival estimates were made using the Kaplan-Meier method. Log-rank statistic was used for comparison of curves. BCR predictors were determined with multivariable Cox regression analysis. Chi-square and Wilcoxon rank-sum tests were used to compare discrete and continuous variables, respectively, across the two groups.

RESULTS

Median follow up for ELND and LLND patients was 46 and 54 months, respectively. ELND yielded more LNs (20 versus 6, p < 0.0001) and had higher node positivity (15.1% versus 3.4%, p < 0.0001). BCR free survival (BCRFS) at 3 and 5 years for ELND and LLND was 85% and 75% (p = 0.01), and 76% and 67% (p = 0.10), respectively. In subgroup analysis, ELND was associated with higher 5 year BCRFS in node-negative patients (84% versus 68%, p = 0.0005) and in intermediate risk patients (93% versus 80%, p = 0.0002). In multivariable analysis, ELND was a significant predictor of BCRFS in node-negative (HR = 0.50, p = 0.003) and intermediate risk patients (HR = 0.54, p = 0.03).

CONCLUSIONS

ELND improves LN yield and detection of positive nodes. BCR analysis suggests a reduced risk of PSA failure for robotic ELND in intermediate risk and node-negative patients.

Multi-institution analysis of racial disparity among African-American men eligible for prostate cancer active surveillance

There is a significant controversy on whether race should be a factor in considering active surveillance for low-risk prostate cancer. To address this question, we analyzed a multi-institution database to assess racial disparity between African-American and White-American men with low risk prostate cancer who were eligible for active surveillance but underwent radical prostatectomy. A retrospective analysis of prospectively collected clinical, pathologic and oncologic outcomes of men with low-risk prostate cancer from seven tertiary care institutions that underwent radical prostatectomy from 2003–2014 were used to assess potential racial disparity. Of the 333 (14.8%) African-American and 1923 (85.2%) White-American men meeting active surveillance criteria, African-American men were found to be slightly younger (57.5 vs 58.5 years old; p = 0.01) and have higher BMI (29.3 v 27.9; p < 0.01), pre-op PSA (5.2 v 4.7; p < 0.01), and maximum percentage cancer on biopsy (15.1% v 13.6%; p < 0.01) compared to White-American men. Univariate and multivariate analysis demonstrated similar rates of upgrading, upstaging, positive surgical margin, and biochemical recurrence between races. These results suggest that single institution studies recommending more stringent AS enrollment criteria for AA men with a low-risk prostate cancer may not capture the complete oncologic landscape due to institutional variability in cancer outcomes. Since all seven institutions demonstrated no significant racial disparity, current active surveillance eligibility should not be modified based upon race until a prospective study has been completed.

Bladder neck preservation improves time to continence after radical prostatectomy: a systematic review and meta-analysis

Bladder neck preservation (BNP) during radical prostatectomy (RP) may improve postoperative urinary continence, although its overall effectiveness remains controversial. We systematically searched PubMed, Ovid Medline, Embase, CBM and the Cochrane Library to identify studies published before February 2016 that assessed associations between BNP and post-RP urinary continence. Thirteen trials (1130 cases and 1154 controls) assessing BNP versus noBNP (or with bladder neck reconstruction, BNR) were considered suitable for meta-analysis, including two randomized controlled trials (RCT), six prospective and five retrospective studies. Meta-analysis demonstrated that BNP improved early urinary continence rates (6 mo, OR = 1.66; 95% CI, 1.21–2.27; P = 0.001) and long-term urinary continence outcomes (>12 mo, OR = 3.99; 95% CI, 1.94–8.21; P = 0.0002). Patients with BNP also had lower bladder neck stricture frequencies (OR = 0.49; 95% CI, 0.29–0.81; P = 0.006). Anastomotic leak rates, positive surgical margins and biochemical failure rates were comparable between the two groups (P>0.05). There were no differences in baseline characteristics except for a smaller average prostate volume (WMD = −2.24 ml; 95% CI, -4.27 to -0.22; P = 0.03) in BNP patients. Our analyses indicated that BNP during RP improved early recovery and overall long-term (1 year) urinary continence and decreased bladder neck stricture rates without compromising oncologic control.

Outcomes and toxicity of 313 prostate cancer patients receiving helical tomotherapy after radical prostatectomy

Purpose

There are limited long-term data on patients treated with image guided intensity modulated radiation therapy (IG-IMRT) for prostate cancer recurrence or high-risk disease features after radical prostatectomy. We report single-institution results for patients treated with IG-IMRT and identify variables associated with outcome.

Methods and materials

This is a retrospective chart review consisting of 313 consecutive patients who were treated with adjuvant or salvage IG-IMRT from 2004 to 2013. Cox proportional hazards analysis was used to identify factors related to survival and toxicity. Toxicity was graded using the Common Terminology Criteria for Adverse Events Version 4.0.

Results

The median follow-up was 55 months (range, 6-131 months). The median pre-radiation therapy (RT) prostate-specific antigen (PSA) was 0.3 ng/mL (range, <0.01-55.4). The vast majority of patients (87%) received elective pelvic nodal irradiation (median dose: 45 Gy). Androgen deprivation therapy (ADT) was given to 39% of patients for a median of 9 months. Five-year biochemical progression-free survival and distant metastasis-free survival were 59% (95% confidence interval, 53%-66%) and 89% (95% confidence interval, 85%-93%), respectively. On multivariate analysis, higher pre-RT PSA (>0.2 ng/mL), biopsy Gleason score (≥7 [4+3]), and duration of ADT (>6 months) were significantly associated (P < .05) with biochemical progression-free survival. Actuarial late grade 3 genitourinary and gastrointestinal toxicities at 5 years were 10% and 2%, respectively.

Conclusion

Our results suggest that lower pre-RT PSA level and longer duration of ADT are associated with improved biochemical control. The incidence of late grade 3 gastrointestinal toxicity was low, but late grade 3 genitourinary toxicity was higher than anticipated.

Focal therapy using magnetic resonance image-guided focused ultrasound in patients with localized prostate cancer

Background

The purpose of this study is to evaluate and report the feasibility, safety, and initial outcomes of patients with limited localized prostate cancer treated using a trans-rectal magnetic resonance image-guided focused ultrasound (MRGFUS) device. Attempts to focally treat only the index lesion for prostate cancer have been explored to reduce side effects while maintaining oncologic control. MRGFUS allows for precise targeting of thermal ablative therapy with real-time thermometry.

Methods

Three patients underwent multiparametric 3T MRI and TRUS-guided 16-sector mapping biopsies of the prostate. The patients were eligible if they had Gleason 6 or 7 (3 + 4) disease, no MRI-visible tumor ≥15 mm, no extracapsular extension, and no more than two discrete cancerous lesions ≤10 mm in length. Acoustic power was adjusted to achieve temperatures of 65 to 85 °C.

Results

Age ranged from 60 to 64 years. The number of biopsy-positive sectors treated ranged from 2 to 4. Post therapy, 16-sector biopsies at 6 months were negative in two patients with one patient still with Gleason 6 cancer (10 %, 2 mm) in one core. 16-sector biopsy in the first patient remains negative at 24 months. PSA continues to remain stable in all patients. IPSS in all patients either remained stable or decreased then stabilized. Erectile function according to the International Index of Erectile Function (IIEF) was excellent for all patients and demonstrated no decline up to the time of last follow-up at 12–24 months.

Conclusions

MRGFUS is a feasible alternative for focal therapy in a select subset of patients with prostate cancer. The treatment is well tolerated with no evidence of decline in functional outcomes. Initial post-therapy biopsy results are promising. Long-term treatment efficacy requires further study.

Use of a mobile tower-based robot--The initial Xi robot experience in surgical oncology

BACKGROUND AND OBJECTIVES

The da Vinci Xi platform provides expanded movement of the arms relative to the base, theoretically allowing increased versatility in complex multi-field or multi-quadrant surgery. We describe the initial Xi experience in oncologic surgery at a tertiary cancer center.

METHODS

One hundred thirty unique robot-assisted procedures were performed using the Xi between 2014 and 2015, 112 of which were oncology surgeries. For procedures involving multiple quadrants, the robot was re-targeted. Complications were assessed according to Martin criteria and the Clavien-Dindo classification up to 90 days after operation.

RESULTS

Thirteen different operations were performed in five oncology subspecialties (urology, gynecology, thoracic, hepatobiliary, and gastrointestinal surgery). Median operative times ranged from 183 min for nephroureterectomy to 543 min for esophagogastrectomy. Median estimated blood loss did not exceed 200 ml for any of the categorized procedures . No patients were transfused intraoperatively and no positioning injuries occurred. Conversions to open operation occurred in three cases (2.7%), though not related to complications or technical considerations. Overall complication rate was 26% with major complication rate of 4%. Readmissions were necessary in 11 (10%) patients.

CONCLUSIONS

The da Vinci Xi can be safely assimilated into a surgical oncology program. The Xi offers versatility to various oncologic procedures with satisfactory complication and readmission rates.

Conditional Survival in de novo Metastatic Urothelial Carcinoma

Background

Second-line therapy is frequently utilized for metastatic urothelial carcinoma, but there are limited data to guide this approach. While an assessment of overall survival based on registry data may not capture the impact of second- and third-line therapies on clinical outcome, this may be reflected in relative conditional survival (RCS).

Methods

Patients with stage IV urothelial carcinoma diagnosed from 1990–2010 were identified from the Surveillance, Epidemiology and End Results (SEER) dataset. The association of clinicopathologic variables with disease specific survival (DSS) was explored through univariate and multivariate analyses. DSS in subgroups divided by time period (1990–2000 v 2001–2010) was compared using the Kaplan-Meier method and log-rank test. One-year RCS at annual landmarks up to 5 years was compared in subgroups divided by time period.

Results

Of 261,987 patients diagnosed with urothelial carcinoma from 1990–2010, 3,110 patients met criteria for the current analysis. Characteristics of patients diagnosed between 1990 and 2000 (n = 810) and 2001 to 2010 (n = 2,300) were similar and there was no significant difference in DSS between the two groups. On multivariate analysis, older age (age ≥ 80) was associated with shorter DSS (HR 1.79, 95%CI 1.48–2.15), but no association was found between time period of diagnosis and outcome. One-year RCS improved substantially through successive annual landmarks up to 5 years, but no differences were seen in subgroups divided by time of diagnosis.

Conclusions

No difference in RCS was observed amongst patients with stage IV urothelial carcinoma diagnosed from 1990–2000 and 2001–2010. A lack of difference in RCS (more so than cumulative DSS) may reflect a lack of progress in salvage therapies for the disease.

Long-term oncologic outcomes following robot-assisted radical cystectomy: results from the International Robotic Cystectomy Consortium

BACKGROUND

Long-term oncologic data on patients undergoing robot-assisted radical cystectomy (RARC) are limited and based largely on single-institution series.

OBJECTIVE

Report survival outcomes of patients who underwent RARC ≥5 yr ago.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective review of the prospectively populated International Robotic Cystectomy Consortium multi-institutional database identified 743 patients with RARC performed ≥5 yr ago. Clinical, pathologic, and survival data at the latest follow-up were collected. Patients with palliative RARC were excluded. Final analysis was performed on 702 patients from 11 institutions in 6 countries.

INTERVENTION

RARC.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Outcomes of interest, recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were plotted using Kaplan-Meier survival curves. A Cox proportional hazards model was used to identify factors that predicted outcomes.

RESULTS AND LIMITATIONS

Pathologic organ-confined (OC) disease was found in 62% of patients. Soft tissue surgical margins (SMs) were positive in 8%. Median lymph node (LN) yield was 16, and 21% of patients had positive LNs. Median follow-up was 67 mo (interquartile range: 18-84 mo). Five-year RFS, CSS, and OS were 67%, 75%, and 50%, respectively. Non-OC disease and SMs were associated with poorer RFS, CSS, and OS on multivariable analysis. Age predicted poorer CSS and OS. Adjuvant chemotherapy and positive SMs were predictors of RFS (hazard ratio: 3.20 and 2.16; p<0.001 and p<0.005, respectively). Stratified survival curves demonstrated poorer outcomes for positive SM, LN, and non-OC disease. Retrospective interrogation and lack of contemporaneous comparison groups that underwent open radical cystectomy were major limitations.

CONCLUSIONS

The largest multi-institutional series to date reported long-term survival outcomes after RARC.

PATIENT SUMMARY

Patients who underwent robot-assisted radical cystectomy for bladder cancer have acceptable long-term survival.

Robot-assisted radical cystectomy and urinary diversion: technical recommendations from the Pasadena Consensus Panel

BACKGROUND

The technique of robot-assisted radical cystectomy (RARC) has evolved significantly since its inception >10 yr ago. Several high-volume centers have reported standardized techniques with refinements and subsequent outcomes.

OBJECTIVE

To review all existing literature on RARC and urinary diversion techniques and summarize key points that may affect oncologic, surgical, and functional outcomes.

DESIGN, SETTING, AND PARTICIPANTS

The Pasadena Consensus Panel on RARC and urinary reconstruction convened May 3-4, 2014, to review the existing peer-reviewed literature and create recommendations for best practice. The panel consisted of experts in open radical cystectomy and RARC. No commercial support was received.

SURGICAL PROCEDURE

The consensus panel extensively reviewed the surgical technique of RARC in men and women, extended pelvic lymph node dissection, extracorporeal urinary diversion, and intracorporeal urinary diversion. Critical aspects of the technique are described.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Preoperative, operative, and postoperative parameters from the largest and most contemporary RARC series, stratified by urinary diversion technique, are presented.

RESULTS AND LIMITATIONS

Preoperative, operative, and postoperative measures of RARC technique adhere closely to the standards established in open surgery.

CONCLUSIONS

Refinement of techniques for RARC and urinary diversion over the past 10 yr has made it safe, reproducible, and oncologically sound.

PATIENT SUMMARY

We summarize the critical aspects of surgical techniques reviewed at the Pasadena international consensus meeting on RARC and urinary reconstruction. Preoperative, operative, and postoperative measures of RARC technique adhere closely to the standards established in open surgery.