Whole-body MRI for staging prostate cancer: a narrative review.

OBJECTIVE: To present a narrative review regarding the diagnostic accuracy of whole-body magnetic resonance imaging (WBMRI) in staging patients with high-risk prostate cancer (HRPCa) and compare it to established imaging modalities. METHODS: A narrative review was carried out using PubMed using the following keywords: 'whole body', 'magnetic resonance imaging', 'MRI', 'prostate cancer', 'risk stratification', and 'staging'. Articles that evaluated WBMRI as the imaging modality to stage patients with HRPCa were included, while studies that solely assessed for biochemical recurrence or metastatic disease progression were excluded. RESULTS: In the evaluation of lymphatic metastases, WBMRI has demonstrated a comparable, if not improved, sensitivity and specificity compared to conventional imaging of computed tomography (CT). Furthermore, WBMRI demonstrates improved sensitivity and specificity in detecting bone metastases compared to bone scintigraphy (BS). However, with advent of prostate-specific membrane antigen (PSMA) radioligands for positron emission tomography (PET), the diagnostic performance of WBMRI to detect metastatic disease appears inferior. CONCLUSIONS: The diagnostic capabilities of WBMRI exceed that of conventional imaging of CT and BS in detecting metastatic disease in patients with HRPCa. However, WBMRI does not perform as well as PSMA PET/CT. Further study on cost comparisons between WBMRI and PSMA PET/CT are needed, as well as evaluations of combined PSMA PET/MRI are needed.

A phase II trial of apalutamide for intermediate-risk prostate cancer and molecular correlates.

OBJECTIVES: To determine whether 6 months of preoperative apalutamide for intermediate-risk prostate cancer (IRPCa) reduces the aggregate postoperative radiotherapy risk and to evaluate associations of molecular perturbations with clinical outcomes in this study cohort. PATIENTS AND METHODS: Between May 2018 and February 2020, eligible patients with IRPCa (Gleason 3 + 4 or 4 + 3 and clinical T2b-c or prostate-specific antigen level of 10-20 ng/mL) were treated with apalutamide 240 mg/day for 6 months followed by radical prostatectomy (RP) in this single-arm, phase II trial. The primary endpoint was presence of any adverse pathological feature at risk of pelvic radiation (pathological T stage after neoadjuvant therapy [yp]T3 or ypN1 or positive surgical margins). Translational studies, including germline and somatic DNA alterations and RNA and protein expression, were performed on post-apalutamide RP specimens, and assessed for associations with clinical outcomes. RESULTS: A total of 40 patients underwent a RP, and only one patient discontinued apalutamide prior to 6 months. In all, 40% had adverse pathological features at time of RP, and the 3-year biochemical recurrence (BCR) rate was 15%, with 27.5% being not evaluable. Genomic alterations frequently seen in metastatic PCas, such as androgen receptor (AR), tumour protein p53 (TP53), phosphatase and tensin homologue (PTEN), or BReast CAncer associated gene (BRCA1/2) were underrepresented in this localised cohort. Adverse pathological features and BCR at 3-years were associated with increased expression of select cell cycle (e.g., E2F targets: adjusted P value [Padj] < 0.001, normalised enrichment score [NES] 2.47) and oxidative phosphorylation (Padj < 0.001, NES 1.62) pathways. CONCLUSIONS: Preoperative apalutamide did not reduce the aggregate postoperative radiation risk to the pre-specified threshold in unselected men with IRPCa. However, transcriptomic analysis identified key dysregulated pathways in tumours associated with adverse pathological outcomes and BCR, which warrant future study. Further investigation of preoperative therapy is underway for men with high-risk PCa.

Surgical Management and Considerations for Patients with Localized High-Risk Prostate Cancer.

OPINION STATEMENT: Localized high-risk (HR) prostate cancer (PCa) is a heterogenous disease state with a wide range of presentations and outcomes. Historically, non-surgical management with radiotherapy and androgen deprivation therapy was the treatment option of choice. However, surgical resection with radical prostatectomy (RP) and pelvic lymph node dissection (PLND) is increasingly utilized as a primary treatment modality for patients with HRPCa. Recent studies have demonstrated that surgery is an equivalent treatment option in select patients with the potential to avoid the side effects from androgen deprivation therapy and radiotherapy combined. Advances in imaging techniques and biomarkers have also improved staging and patient selection for surgical resection. Advances in robotic surgical technology grant surgeons various techniques to perform RP, even in patients with HR disease, which can reduce the morbidity of the procedure without sacrificing oncologic outcomes. Clinical trials are not only being performed to assess the safety and oncologic outcomes of these surgical techniques, but to also evaluate the role of surgical resection as a part of a multimodal treatment plan. Further research is needed to determine the ideal role of surgery to potentially provide a more personalized and tailored treatment plan for patients with localized HR PCa.

Apixaban vs Enoxaparin for Post-Surgical Extended-Duration Venous Thromboembolic Event Prophylaxis: A Prospective Quality Improvement Study.

PURPOSE: Venous thromboembolic events (VTEs) are a major cause of morbidity following abdominopelvic oncologic surgery. Enoxaparin, a subcutaneous injectable low molecular weight heparin, is commonly used for extended-duration VTE prophylaxis (EP), but has been associated with noncompliance. Newer direct oral anticoagulants have not been prospectively studied in the urologic oncology post-discharge setting. We aimed to improve compliance with EP following abdominopelvic oncologic surgery and secondarily test the hypothesis that apixaban is noninferior to enoxaparin for EP. MATERIALS AND METHODS: A single-center prospective quality improvement study measuring patient compliance and safety with EP was conducted between August 10, 2020 and September 21, 2021. Baseline data were continuously collected for 6 months, followed by a uniform departmental change from enoxaparin to apixaban. The duration of data collection was determined a priori using a noninferiority sample size estimation (145 per group). The primary outcome was compliance events (real or potential barriers to EP use). The secondary outcome was 30-day post-discharge safety events (symptomatic VTE or major bleed). RESULTS: A total of 161 patients were discharged with enoxaparin (baseline period) and 154 with apixaban (intervention period). Safety events occurred in 3.1% vs 0% of patients receiving enoxaparin and apixaban, respectively. The absolute risk difference of 3.1% (95% CI: 0.043%-5.8%) met the prespecified noninferiority threshold (p=0.028 for apixaban superiority). Compliance events occurred in 33.5% of enoxaparin patients and 14.3% of apixaban patients (p=0.0001). CONCLUSIONS: There were fewer compliance events using apixaban for EP than enoxaparin after urologic oncology surgery. Regarding safety, apixaban is noninferior to enoxaparin and may in fact have fewer associated major complications.

Adherence to the Mediterranean diet and grade group progression in localized prostate cancer: An active surveillance cohort.

BACKGROUND: The Mediterranean diet (MD) may be beneficial for men with localized prostate cancer (PCa) on active surveillance (AS) because of its anti-inflammatory, antilipidemic, and chemopreventive properties. This study prospectively investigated adherence to the MD with Gleason score progression and explored associations by diabetes status, statin use, and other factors. METHODS: Men with newly diagnosed PCa on an AS protocol (n = 410) completed a baseline food frequency questionnaire, and the MD score was calculated across 9 energy-adjusted food groups. Cox proportional hazards models were fit to evaluate multivariable-adjusted associations of the MD score with progression-free survival; progression was defined as an increase in the Gleason grade group (GG) score over a biennial monitoring regimen. RESULTS: In this cohort, 15% of the men were diabetic, 44% of the men used statins, and 76 men progressed (median follow-up, 36 months). After adjustments for clinical factors, higher adherence to the MD was associated with a lower risk of GG progression among all men (hazard ratio [HR] per 1-unit increase in MD score, 0.88; 95% confidence interval [CI], 0.77-1.01), non-White men (HR per 1-unit increase in MD score, 0.64; 95% CI, 0.45-0.92; P for interaction = .07), and men without diabetes (HR per 1-unit increase in MD score, 0.82; 95% CI, 0.71-0.96; P for interaction = .03). When joint effects of the MD score and statin use were examined, a similar risk reduction was observed among men with high MD scores who did not use statins in comparison with men with low/moderate MD scores with no statin use. CONCLUSIONS: The MD is associated with a lower risk of GG progression in men on AS, and this is consistent with prior reports about the MD and reduced cancer morbidity and mortality.

The Association of Periprostatic Fat and Grade Group Progression in Men with Localized Prostate Cancer on Active Surveillance.

PURPOSE: Evidence suggests that visceral fat quantity may be associated with post-prostatectomy outcomes and risk of prostate cancer related death. We evaluated whether increased fat volume, normalized to prostate size, is associated with decreased risk of disease progression. MATERIALS AND METHODS: Patients enrolled on a prospective active surveillance trial for at least 6 months who had magnetic resonance imaging within 2 years of enrollment were eligible. The surveillance protocol included a standardized followup regimen consisting of biennial prostate specific antigen and examination and yearly biopsy. Clinicopathological characteristics were collected at baseline. Three fat measurements were taken using prostate magnetic resonance imaging, including subcutaneous, linear periprostatic (pubic symphysis to prostate) and volumetrically defined periprostatic. Progression was defined as increase in Gleason grade group. Multivariable Cox proportional hazards models were used to evaluate fat volumes normalized by prostate size (stratified into tertiles). RESULTS: A total of 175 patients were included in the study. Average age was 62.5 years (SD 7.4) and average prostate specific antigen was 5.4 ng/dl (SD 3.9). Median followup was 42 months (IQR 18-60) and 50 patients (28.6%) had progression. Compared to the lowest tertile, the highest tertile of volumetric periprostatic fat measurement (HR 2.63, 95% CI 1.23-5.60, p=0.01) and linear periprostatic fat measurement (HR 2.30, 95% CI 1.01-5.22, p=0.05) were associated with worsened progression-free survival, while subcutaneous fat measurement (p=0.97) was not. Importantly, the model did not substantively change when accounting for patient body mass index and other factors. CONCLUSIONS: Increased periprostatic fat volume, normalized to prostate size, may be associated with shortened progression-free survival in men with prostate cancer on active surveillance.

Comparing confirmatory biopsy outcomes between MRI-targeted biopsy and standard systematic biopsy among men being enrolled in prostate cancer active surveillance.

OBJECTIVES: To evaluate the ability of magnetic resonance imaging (MRI)-targeted biopsy combined with systematic biopsy (MRI-biopsy) to reduce negative biopsies and detect clinically significant prostate cancer compared to systematic biopsy (SB) alone in the confirmatory biopsy setting using matched cohorts. PATIENTS AND METHODS: Patients were identified from an active surveillance database who had a previously positive transrectal ultrasonography-guided SB followed by a confirmatory biopsy at a single institution between 2006 and 2019. Patients were divided into two cohorts based on confirmatory biopsy technique: SB alone or MRI-biopsy (which included MRI-targeted and systematic biopsies). Cohorts were then matched on age, prostate-specific antigen (PSA) level, number of positive cores on initial biopsy and initial biopsy Gleason grade group (GG). Logistic regression was performed to identify associations with confirmatory biopsy upgrading. RESULTS: After matching, 514 patients were identified (257 per cohort). PSA, prostate volume and PSA density prior to initial biopsy, in addition to total number of initial biopsy positive cores and GG, were similar between the matched cohorts. After confirmatory biopsy, 118/257 patients (45.9%) in the MRI-biopsy cohort were upgraded compared to 46/257 patients (17.9%) in the SB cohort (P < 0.001). The rate of negative confirmatory biopsy was 32/257 (12.5%) compared to 97/257 (37.7%) in the MRI-biopsy and SB cohorts, respectively (P < 0.001). Confirmatory MRI-biopsy was associated with greater odds of confirmatory biopsy upgrade from GG 1 to ≥GG 2 compared to SB alone (odds ratio 3.62, 95% confidence interval 1.97-6.63; P < 0.001). CONCLUSION: The addition of MRI-targeted biopsies to SB in the confirmatory biopsy setting among men with previously detected prostate cancer resulted in fewer negative confirmatory biopsies and detection of more clinically significant prostate cancer compared to SB alone.

Prospective trial of regional (hockey-stick) prostate cryoablation: oncologic and quality of life outcomes.

PURPOSE: To report long-term follow-up of the efficacy of subtotal prostate ablation using a "hockey-stick" template, including oncologic control and quality of life (QoL) impact. METHODS: We performed a prospective controlled trial to evaluate the efficacy of subtotal prostate ablation in selected men with baseline and confirmatory biopsy showing grade group (GG) 1-2 prostate cancer. "Hockey-stick" cryoablation that included the ipsilateral hemi-gland and contralateral anterior prostate was performed. Prostate biopsies and QOL queries were performed at 6, 18 and 36 months following regional ablation, and follow-up was updated to include subsequent clinic visits. RESULTS: Between August 2009 and January 2012, 72 men were screened for eligibility and 47 opted to undergo confirmatory biopsy. Of these, 23 were deemed eligible and treated with regional cryoablation. Median age was 64 years. Median follow-up was 74 months. A single patient had < 1 mm of in-field viable tumor with therapy effect on 36-month biopsy. At time of last follow-up, a total of 12/23 (52%) patients did not have evidence of disease, all patients had preserved urinary control with no patients requiring pads for urinary incontinence. Sexual decline was significant at 3 and 6 months (P < 0.01 for both), though improvement was seen at subsequent time points. CONCLUSION: Subtotal (hockey-stick template) cryoablation of the prostate provides oncologic control to targeted tissue in a generally low-risk group with minimal impact on sexual and urinary function. Further studies are needed to evaluate this ablation template in the MRI-targeted era and higher risk populations.

Diet quality and Gleason grade progression among localised prostate cancer patients on active surveillance.

BACKGROUND: High diet quality may support a metabolic and anti-inflammatory state less conducive to tumour progression. We prospectively investigated diet quality in relation to Gleason grade progression among localised prostate cancer patients on active surveillance, a clinical management strategy of disease monitoring and delayed intervention. METHODS: Men with newly diagnosed Gleason score 6 or 7 prostate cancer enroled on a biennial monitoring regimen. Patients completed a food frequency questionnaire (FFQ) at baseline (n = 411) and first 6-month follow-up (n = 263). Cox proportional hazards models were fitted to evaluate multivariable-adjusted associations of diet quality [defined via the Healthy Eating Index (HEI)-2015] with Gleason grade progression. RESULTS: After a median follow-up of 36 months, 76 men progressed. Following adjustment for clinicopathologic factors, we observed a suggestive inverse association between baseline diet quality and Gleason grade progression [hazard ratio (HR) and 95% confidence interval (CI) for the highest vs. the lowest HEI-2015 tertile: 0.59 (0.32-1.08); Ptrend = 0.06]. We observed no associations with diet quality at 6-month follow-up, nor change in diet quality from baseline. CONCLUSIONS: In localised prostate cancer patients on surveillance, higher diet quality or conformance with United States dietary guidelines at enrolment may lower risk of Gleason grade progression, though additional confirmatory research is needed.

Coffee, Caffeine Metabolism Genotype and Disease Progression in Patients with Localized Prostate Cancer Managed with Active Surveillance.

PURPOSE: Active surveillance is increasingly used as a management strategy for localized prostate cancer. Coffee intake has been associated with a lower prostate cancer incidence. We assessed whether coffee was associated with disease progression in men on active surveillance. MATERIALS AND METHODS: A total of 411 patients with newly diagnosed Gleason score 6 or 7 prostate cancer were enrolled on a prospective active surveillance protocol for at least 6 months and completed a baseline dietary assessment. The active surveillance protocol included a biennial monitoring regimen with disease progression defined as an increase in the Gleason score. Cox proportional hazards models were used to evaluate associations of coffee intake with progression-free survival. We also evaluated patient genotype in the caffeine metabolism related single nucleotide polymorphism rs762551. RESULTS: Median followup was 36 months (range 6 to 126) and the Gleason score progressed in 76 of the 411 patients (18.5%). Compared to 0 cups per day, in the multivariable model adjusting for prostate specific antigen, patient age and tumor length, less than 1 cup (HR 0.85, 95% CI 0.40-1.71), 1 to 1.9 cups (HR 0.64, 95% CI 0.29-1.43), 2 to 3.9 cups (HR 0.71, 95% CI 0.35-1.47) and 4 cups or more (HR 1.67, 95% CI 0.81-3.45) were not significantly associated with progression-free survival (p for nonlinearity = 0.01). Patients with low/moderate coffee intake and the AA fast caffeine metabolizer genotype were less likely to experience grade progression than nonconsumers (HR 0.36, 95% CI 0.15-0.88, p = 0.03). CONCLUSIONS: Low to moderate coffee intake appears safe in men on active surveillance of localized prostate cancer. Further work is needed to determine whether high consumption is associated with shorter progression-free survival in sensitive groups.

An Evidence-Based Protocol for Antibiotic Use Prior to Cystoscopy Decreases Antibiotic Use without Impacting Post-Procedural Symptomatic Urinary Tract Infection Rates.

PURPOSE: Symptomatic urinary tract infection is a complication of office based cystourethroscopy. Studies are mixed regarding the efficacy of antibiotic prophylaxis to prevent urinary tract infections. Our aim was to develop and evaluate an evidence-based protocol that reduces unnecessary antibiotic use while avoiding an increase in urinary tract infections. MATERIALS AND METHODS: We created a clinic antibiogram based on all urology office visits performed during a 2-year period. Bacterial resistance rates, institutional risk related data and clinical guidelines were applied to create a protocol for antibiotic administration before cystourethroscopy. We then analyzed 1,245 consecutive patients without a renal transplant who underwent outpatient cystourethroscopy, including 610 after protocol initiation. Urinary tract infection rates and antibiotic use were analyzed for an association with the protocol change using the Fisher exact test. RESULTS: Cultures had an overall 20% rate of resistance to fluoroquinolones, representing 40% of the cultures that grew Escherichia coli. Before the protocol change 602 of 635 patients (94.8%) received a preprocedural antibiotic compared to 426 of 610 (69.9%) after protocol initiation (p <0.01). A total of 19 patients (3.0%) had a symptomatic urinary tract infection prior to the protocol change while 16 (2.6%) had a urinary tract infection after the change (p = 0.69). Regarding resistance, fluoroquinolone resistant organisms grew in the cultures of 12 of 19 patients (63.2%) with a urinary tract infection before the protocol change compared to 5 of 16 (31.3%) with a urinary tract infection after the change. Recent antibiotic administration, hospitalization and chronic catheterization were associated with urinary tract infection in the entire cohort (all p ≤0.01). CONCLUSIONS: A local antibiogram with infection related risk data effectively risk stratifies patients before cystourethroscopy, decreasing the use of antibiotics without increasing the rate of symptomatic urinary tract infection.

The Null Effect of Bladder Neck Size on Incontinence Outcomes after Radical Prostatectomy.

PURPOSE: We sought to determine whether bladder neck size is associated with incontinence scores after robot-assisted laparoscopic radical prostatectomy. MATERIALS AND METHODS: Consecutive eligible patients undergoing robot-assisted laparoscopic radical prostatectomy between July 19 and December 28, 2016 were enrolled in a prospective, longitudinal, observational cohort study. The primary outcome was patient reported urinary incontinence on the EPIC (Expanded Prostate Cancer Index Composite) scale 6 and 12 weeks postoperatively. The relationship between the EPIC score of urinary incontinence and bladder neck size was evaluated by multiple regression. Predicted EPIC scores for incontinence were displayed graphically after using restricted cubic splines to model bladder neck size. RESULTS: A total of 107 patients were enrolled. The response rate was 98% and 87% at 6 and 12 weeks, respectively. Bladder neck size was not significantly associated with incontinence scores at 6 and 12 weeks. Comparing the 90th percentile for bladder neck size (18 mm) with the 10th percentile (7 mm) revealed no significant difference in adjusted EPIC scores for incontinence at 6 weeks (ß coefficient 0.88, 95% CI -10.92-12.68, p = 0.88) or at 12 weeks (ß coefficient 5.80, 95% CI -7.36-18.97, p = 0.39). CONCLUSIONS: These findings question the merit of creating an extremely small bladder neck during robot-assisted laparoscopic radical prostatectomy. We contend that doing so increases the risk of positive margins at the bladder neck without facilitating early recovery of continence.

Oncologic Outcomes after Anterior Exenteration for Muscle Invasive Bladder Cancer in Women.

PURPOSE: We investigated oncologic and urinary outcomes after anterior exenteration for urothelial cell carcinoma in females, identifying tumor characteristics associated with female pelvic organ involvement. We hypothesized that a lack of trigonal or bladder floor tumor, intraoperative palpable posterior mass and clinical lymphadenopathy is associated with a lack of female pelvic organ involvement. MATERIALS AND METHODS: We retrospectively reviewed the charts of female patients who underwent radical cystectomy at our institution from 1999 to 2014. Patient and operative characteristics were extracted from the electronic medical record, and performance of hysterectomy was tested for association with disease recurrence. Categorical and continuous variables were analyzed with the chi-square and Student t-test, and Kaplan-Meier analysis was performed to determine recurrence-free survival according to hysterectomy performance. Women who had neobladder creation were additionally evaluated for an association between hysterectomy status, and nighttime wetting and catheter use. RESULTS: Of 322 eligible patients 160 with urothelial cancer did not have a hysterectomy before cystectomy. Mean followup was 2.2 years (SD 2.8). There were 22 patients (13.8%) who had recurrence during followup. No patient or surgical factor other than use of adjuvant chemotherapy or radiation (p <0.01) was associated with recurrence. Of 139 women 32 (23.0%) who underwent exenteration had female pelvic organ involvement. At least 1 of the 3 characteristics of interest were present in 28 of 99 (28.3%) women with any genitourinary organ involvement compared to only 4 of 40 (10.0%) of those who did not (p=0.01). Nighttime continence ranged between 21.9% and 48% but there was no significant association with continence and hysterectomy status. CONCLUSIONS: Lack of trigonal/bladder floor tumor, palpable posterior mass and clinical lymphadenopathy is associated with the absence of pelvic organ involvement. Individualized risk assessment using these factors along with patient preferences should be used to guide surgical planning.

Short term complications from transurethral resection of bladder tumor.

INTRODUCTION: The diagnosis and subsequent management of bladder cancer often involves transurethral resection of bladder tumor (TURBT). Risks of TURBT include perioperative complications such as bleeding, pain and perforation. We aimed to determine TURBT complication rates and risk factors in a contemporary series. MATERIALS AND METHODS: From 2002 to 2011, 505 patients underwent TURBT either for suspected bladder cancer or during follow up at a single institution. Baseline patient characteristics and complications within 2 weeks of surgery were extracted from the electronic medical record for all TURBTs. Patient and tumor characteristics were evaluated for associations with complication using univariate analysis. A multivariable logistic regression was fit to further examine associations between TURBT related characteristics and complication. RESULTS: A total of 910 TURBTs were performed on 505 patients. Overall complication rate was 8.1%. The most common complications were pain or spasm (3.0%), retention (2.8%), and infection (2.1%), and 0.5% of TURBTs had perforation. Over 85% of complications were Clavien-Dindo grade I or II. Forty-three patients had a complication after their first TURBT, while 25 had complications after subsequent TURBTs. Prior complication and single tumor, but not other patient or tumor-related characteristics, were associated with complication. Only prior complication (p < 0.01) was associated with subsequent complication after TURBT on multivariable analysis. CONCLUSIONS: Complication rate after TURBT is 8.1% and complications are generally not severe in nature. Prior short term complication is likely associated with subsequent complication. Further studies are needed to validate these results and determine patient groups most at risk for intraoperative and post TURBT complications.

Guideline-based management of non-muscle invasive bladder cancer.

INTRODUCTION: Non-muscle invasive bladder cancer (NMIBC) represents a broad spectrum of disease, the hallmarks of which include disease recurrence and progression. Clinicians have a number of surgical and therapeutic options at their disposal when treating this disease, and the underlying evidence continues to evolve. A number of professional organizations have invested in the development of clinical practice guidelines to guide patient management. MATERIALS AND METHODS: We review and summarize four major guidelines, the American Urological Association, the European Association of Urology, the International Consultation on Urological Disease and the National Comprehensive Cancer Network. RESULTS: Guideline panels differed in their composition, methodological approach and structure of recommendations. Despite this, many recommendations were similar between various panels, although differences are present in panel recommendations related to initial diagnosis and treatment, adjuvant therapy and disease surveillance. CONCLUSIONS: Guideline recommendations are similar at many decision points that clinicians face when managing NMIBC, although they are far from uniform. While future prospective, well-designed studies will hopefully clarify NMIBC management, urologists ultimately must rely on a combination of evidence-based recommendations, which they should seek to integrate with patients' values and preferences and the individual circumstances to provide the best possible patient care.

Patient enrollment onto clinical trials: the role of physician knowledge.

Sixty-six attending physicians at academic medical centers completed a 43-question self-assessment evaluating communication skills, comfort with clinical trial enrollment, and knowledge of patient-related barriers to enrollment on clinical trials. Responses and demographic information were analyzed for trends and for association with estimated trial enrollment. Physician-described enrollment of patients onto trials varied widely, with estimated enrollment varying from less than 5 patients to well over 125 enrolled during the previous year. Participants perceived themselves to have excellent communication skills and were comfortable with the trial enrollment process, though did not consistently identify patient-related barriers to enrollment. Physician knowledge of clinical trials currently enrolling within their field was associated with increased patient enrollment on study (p = 0.03). Academic physicians expressed confidence in their skills related to clinical trial enrollment despite less than ideal reported enrollment. Knowledge of clinical trials currently enrolling within a physician's specialty was associated with estimated patient enrollment, and may represent a correctable barrier to trial enrollment.