Can computer-aided diagnosis assist in the identification of prostate cancer on prostate MRI? a multi-center, multi-reader investigation.

For prostate cancer detection on prostate multiparametric MRI (mpMRI), the Prostate Imaging-Reporting and Data System version 2 (PI-RADSv2) and computer-aided diagnosis (CAD) systems aim to widely improve standardization across radiologists and centers. Our goal was to evaluate CAD assistance in prostate cancer detection compared with conventional mpMRI interpretation in a diverse dataset acquired from five institutions tested by nine readers of varying experience levels, in total representing 14 globally spread institutions. Index lesion sensitivities of mpMRI-alone were 79% (whole prostate (WP)), 84% (peripheral zone (PZ)), 71% (transition zone (TZ)), similar to CAD at 76% (WP, p=0.39), 77% (PZ, p=0.07), 79% (TZ, p=0.15). Greatest CAD benefit was in TZ for moderately-experienced readers at PI-RADSv2 <3 (84% vs mpMRI-alone 67%, p=0.055). Detection agreement was unchanged but CAD-assisted read times improved (4.6 vs 3.4 minutes, p<0.001). At PI-RADSv2 ≥ 3, CAD improved patient-level specificity (72%) compared to mpMRI-alone (45%, p<0.001). PI-RADSv2 and CAD-assisted mpMRI interpretations have similar sensitivities across multiple sites and readers while CAD has potential to improve specificity and moderately-experienced radiologists' detection of more difficult tumors in the center of the gland. The multi-institutional evidence provided is essential to future prostate MRI and CAD development

MRI-Guided Robotically Assisted Focal Laser Ablation of the Prostate Using Canine Cadavers

© 1964-2012 IEEE. Objective: a magnetic resonance imaging (MRI)-conditional needle guidance robot is developed to enhance MRI-guided focal laser ablation (FLA) therapy in patients with focal prostate cancer. Methods: inspired by the workflow of the manual FLA therapy, we developed an MRI-conditional robot with two degrees of freedom to provide the guidance for laser ablation catheter. This robot is powered by pneumatic turbine motors and encoded with the custom-designed optical encoder. The needle could be inserted manually through the designed robotic system, which keeps the patients inside MRI bore throughout the procedure. The robot hardware is integrated with the custom ablation planning and monitoring software (OncoNav) to provide an iterative treatment plan to cover the whole ablation zone. Virtual tumors were selected in three canine cadavers as targets to validate the performance of the proposed hardware and software system. Results: phantom studies show that the average targeting error is less than 2 mm and the workflow of the entire procedure lasts for 100 minutes. Canine cadaver experiment results show that all the targets were successfully ablated in no more than three administrations. Significance: MRI-guided prostate FLA is feasible using the proposed hardware and software system, indicating potential utility in future human trials

Comprehensive Endocrine-Metabolic Evaluation of Patients With Alström Syndrome Compared With BMI-Matched Controls.

Background: Alström syndrome (AS), a monogenic form of obesity, is caused by recessive mutations in the centrosome- and basal body-associated gene ALMS1. AS is characterized by retinal dystrophy, sensory hearing loss, cardiomyopathy, childhood obesity, and metabolic derangements. Objective: We sought to characterize the endocrine and metabolic features of AS while accounting for obesity as a confounder by comparing patients with AS to body mass index (BMI)-matched controls. Methods: We evaluated 38 patients with AS (age 2 to 38 years) who were matched with 76 controls (age 2 to 48 years) by age, sex, race, and BMI. Fasting biochemistries, mixed meal test (MMT), indirect calorimetry, dual-energy X-ray absorptiometry, and MRI/magnetic resonance spectroscopy were performed. Results: Frequent abnormalities in AS included 76% obesity, 37% type 2 diabetes mellitus (T2DM), 29% hypothyroidism (one-third central, two-thirds primary), 3% central adrenal insufficiency, 57% adult hypogonadism (one-third central, two-thirds primary), and 25% female hyperandrogenism. Patients with AS and controls had similar BMI z scores, body fat, waist circumference, abdominal visceral fat, muscle fat, resting energy expenditure (adjusted for lean mass), free fatty acids, glucagon, prolactin, ACTH, and cortisol. Compared with controls, patients with AS were shorter and had lower IGF-1 concentrations (Ps ≤ 0.001). Patients with AS had significantly greater fasting and MMT insulin resistance indices, higher MMT glucose, insulin, and C-peptide values, higher HbA1c, and higher prevalence of T2DM (Ps \u3c 0.001). Patients with AS had significantly higher triglycerides, lower high-density lipoprotein cholesterol, and a 10-fold greater prevalence of metabolic syndrome (Ps \u3c 0.001). Patients with AS demonstrated significantly greater liver triglyceride accumulation and higher transaminases (P \u3c 0.001). Conclusion: Severe insulin resistance and T2DM are the hallmarks of AS. However, patients with AS may present with multiple other endocrinopathies affecting growth and development

AUA Policy Statement on the Use of Multiparametric Magnetic Resonance Imaging in the Diagnosis, Staging and Management of Prostate Cancer

PurposeWe summarize the available data about the clinical and economic effectiveness of magnetic resonance imaging in the diagnosis and management of prostate cancer, and provide practical recommendations for its use in the screening, diagnosis, staging and surveillance of prostate cancer.Materials and methodsA panel of clinicians with expertise in the diagnosis and management of prostate cancer evaluated the current published literature on the use and effectiveness of magnetic resonance imaging for this disease. When adequate studies were available for analysis, recommendations were made on the basis of data and when adequate studies were not available, recommendations were made on the basis of expert consensus.ResultsAt this time the data support the use of magnetic resonance imaging in patients with a previous negative biopsy and ongoing concerns about increased risk of prostate cancer. The data regarding its usefulness for initial biopsy suggest a possible role for magnetic resonance imaging in some circumstances. There is currently insufficient evidence to recommend magnetic resonance imaging for screening, staging or surveillance of prostate cancer.ConclusionsAlthough it adds cost to the management of prostate cancer, magnetic resonance imaging offers superior anatomic detail, and the ability to evaluate cellular density based on water diffusion and blood flow based on contrast enhancement. Imaging targeted biopsy may increase the diagnosis of clinically significant cancers by identifying specific lesions not visible on conventional ultrasound. The clinical indications for the use of magnetic resonance imaging in the management of prostate cancer are rapidly evolving

Neoadjuvant PROSTVAC prior to radical prostatectomy enhances T-cell infiltration into the tumor immune microenvironment in men with prostate cancer

BackgroundClinical trials have shown the ability of therapeutic vaccines to generate immune responses to tumor-associated antigens (TAAs). What is relatively less known is if this translates into immune-cell (IC) infiltration into the tumor microenvironment. This study examined whether neoadjuvant prostate-specific antigen (PSA)-targeted vaccination with PROSTVAC could induce T-cell immunity, particularly at the tumor site.MethodsAn open-label, phase II study of neoadjuvant PROSTVAC vaccine enrolled 27 patients with localized prostate cancer awaiting radical prostatectomy (RP). We evaluated increases in CD4 and CD8 T-cell infiltrates (RP tissue vs baseline biopsies) using a six-color multiplex immunofluorescence Opal method. Antigen-specific responses were assessed by intracellular cytokine staining after in vitro stimulation of peripheral blood mononuclear cells with overlapping 15-mer peptide pools encoding the TAAs PSA, brachyury and MUC-1.ResultsOf 27 vaccinated patients, 26 had matched prevaccination (biopsy) and postvaccination (RP) prostate samples available for non-compartmentalized analysis (NCA) and compartmentalized analysis (CA). Tumor CD4 T-cell infiltrates were significantly increased in postvaccination RP specimens compared with baseline biopsies by NCA (median 176/mm² vs 152/mm²; IQR 136–317/mm² vs 69–284/mm²; p=0.0249; median ratio 1.20; IQR 0.64–2.25). By CA, an increase in both CD4 T-cell infiltrates at the tumor infiltrative margin (median 198/mm² vs 151/mm²; IQR 123–500/mm² vs 85–256/mm²; p=0.042; median ratio 1.44; IQR 0.59–4.17) and in CD8 T-cell infiltrates at the tumor core (median 140/mm² vs 105/mm²; IQR 91–175/mm² vs 83–163/mm²; p=0.036; median ratio 1.25; IQR 0.88–2.09) were noted in postvaccination RP specimens compared with baseline biopsies. A total of 13/25 patients (52%) developed peripheral T-cell responses to any of the three tested TAAs (non-neoantigens); five of these had responses to more than one antigen of the three evaluated.ConclusionNeoadjuvant PROSTVAC can induce both tumor immune response and peripheral immune response.Trial registration numberNCT02153918