Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 99
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
BJU Int ; 132(5): 581-590, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37488983

RESUMEN

OBJECTIVE: To evaluate the prognostic value of programmed death ligand-1 (PD-L1) and programmed death-1 (PD-1) expression in patients with upper tract urothelial carcinoma (UTUC). PATIENTS AND METHODS: A retrospective multicentre study was conducted in 283 patients with UTUC treated with radical nephroureterectomy (RNU) between 2000 and 2015 at 10 French hospitals. Immunohistochemistry analyses were performed using 2 mm-core tissue microarrays with NAT105® and 28.8® antibodies at a 5% cut-off for positivity on tumour cells and tumour-infiltrating lymphocytes to evaluate PD-L1 and PD-1 expression, respectively. Multivariable Cox regression models were used to determine the independent predictors of recurrence-free (RFS), cancer-specific (CSS) and overall survival (OS). RESULTS: Overall, 63 (22.3%) and 220 (77.7%) patients with UTUC had PD-L1-positive and -negative disease, respectively, while 91 (32.2%) and 192 (67.8%) had PD-1-positive and -negative disease, respectively. Patients who expressed PD-L1 or PD-1 were more likely to have pathological tumour stage ≥pT2 (68.3% vs 49.5%, P = 0.009; and 69.2% vs 46.4%, P < 0.001, respectively) and high-grade (90.5% vs 70.0%, P = 0.001; and 91.2% vs 66.7%, P < 0.001, respectively) disease with lymphovascular invasion (52.4% vs 17.3%, P < 0.001; and 39.6% vs 18.2%, P < 0.001, respectively) as compared to those who did not. In multivariable Cox regression analysis adjusting for each other, PD-L1 and PD-1 expression were significantly associated with decreased RFS (hazard ratio [HR] 1.83, 95% confidence interval [CI] 1.09-3.08, P = 0.023; and HR 1.59, 95% CI 1.01-2.54, P = 0.049; respectively), CSS (HR 2.73, 95% CI 1.48-5.04, P = 0.001; and HR 1.96, 95% CI 1.12-3.45, P = 0.019; respectively) and OS (HR 2.08, 95% CI 1.23-3.53, P = 0.006; and HR 1.71, 95% CI 1.05-2.78, P = 0.031; respectively). In addition, multivariable Cox regression analyses evaluating the four-tier combination of PD-L1 and PD-1 expression showed that only PD-L1/PD-1-positive patients (n = 38 [13.4%]) had significantly decreased RFS (HR 3.07, 95% CI 1.70-5.52; P < 0.001), CSS (HR 5.23, 95% CI 2.62-10.43; P < 0.001) and OS (HR 3.82, 95% CI 2.13-6.85; P < 0.001) as compared to those with PD-L1/PD-1-negative disease (n = 167 [59.0%]). CONCLUSIONS: We observed that PD-L1 and PD-1 expression were both associated with adverse pathological features that translated into an independent and cumulative adverse prognostic value in UTUC patients treated with RNU.

2.
World J Urol ; 41(12): 3527-3533, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37845554

RESUMEN

PURPOSE: To assess a region-of-interest-based computer-assisted diagnosis system (CAD) in characterizing aggressive prostate cancer on magnetic resonance imaging (MRI) from patients under active surveillance (AS). METHODS: A prospective biopsy database was retrospectively searched for patients under AS who underwent MRI and subsequent biopsy at our institution. MRI lesions targeted at baseline biopsy were retrospectively delineated to calculate the CAD score that was compared to the Prostate Imaging-Reporting and Data System (PI-RADS) version 2 score assigned at baseline biopsy. RESULTS: 186 patients were selected. At baseline biopsy, 51 and 15 patients had International Society of Urological Pathology (ISUP) grade ≥ 2 and ≥ 3 cancer respectively. The CAD score had significantly higher specificity for ISUP ≥ 2 cancers (60% [95% confidence interval (CI): 51-68]) than the PI-RADS score (≥ 3 dichotomization: 24% [CI: 17-33], p = 0.0003; ≥ 4 dichotomization: 32% [CI: 24-40], p = 0.0003). It had significantly lower sensitivity than the PI-RADS ≥ 3 dichotomization (85% [CI: 74-92] versus 98% [CI: 91-100], p = 0.015) but not than the PI-RADS ≥ 4 dichotomization (94% [CI:85-98], p = 0.104). Combining CAD findings and PSA density could have avoided 47/184 (26%) baseline biopsies, while missing 3/51 (6%) ISUP 2 and no ISUP ≥ 3 cancers. Patients with baseline negative CAD findings and PSAd < 0.15 ng/mL2 who stayed on AS after baseline biopsy had a 9% (4/44) risk of being diagnosed with ISUP ≥ 2 cancer during a median follow-up of 41 months, as opposed to 24% (18/74) for the others. CONCLUSION: The CAD could help define AS patients with low risk of aggressive cancer at baseline assessment and during subsequent follow-up.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Estudios Prospectivos , Espera Vigilante , Diagnóstico por Computador , Computadores , Biopsia Guiada por Imagen/métodos , Antígeno Prostático Específico
3.
Eur Radiol ; 32(5): 3248-3259, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35001157

RESUMEN

OBJECTIVE: To train and to test for prostate zonal segmentation an existing algorithm already trained for whole-gland segmentation. METHODS: The algorithm, combining model-based and deep learning-based approaches, was trained for zonal segmentation using the NCI-ISBI-2013 dataset and 70 T2-weighted datasets acquired at an academic centre. Test datasets were randomly selected among examinations performed at this centre on one of two scanners (General Electric, 1.5 T; Philips, 3 T) not used for training. Automated segmentations were corrected by two independent radiologists. When segmentation was initiated outside the prostate, images were cropped and segmentation repeated. Factors influencing the algorithm's mean Dice similarity coefficient (DSC) and its precision were assessed using beta regression. RESULTS: Eighty-two test datasets were selected; one was excluded. In 13/81 datasets, segmentation started outside the prostate, but zonal segmentation was possible after image cropping. Depending on the radiologist chosen as reference, algorithm's median DSCs were 96.4/97.4%, 91.8/93.0% and 79.9/89.6% for whole-gland, central gland and anterior fibromuscular stroma (AFMS) segmentations, respectively. DSCs comparing radiologists' delineations were 95.8%, 93.6% and 81.7%, respectively. For all segmentation tasks, the scanner used for imaging significantly influenced the mean DSC and its precision, and the mean DSC was significantly lower in cases with initial segmentation outside the prostate. For central gland segmentation, the mean DSC was also significantly lower in larger prostates. The radiologist chosen as reference had no significant impact, except for AFMS segmentation. CONCLUSIONS: The algorithm performance fell within the range of inter-reader variability but remained significantly impacted by the scanner used for imaging. KEY POINTS: • Median Dice similarity coefficients obtained by the algorithm fell within human inter-reader variability for the three segmentation tasks (whole gland, central gland, anterior fibromuscular stroma). • The scanner used for imaging significantly impacted the performance of the automated segmentation for the three segmentation tasks. • The performance of the automated segmentation of the anterior fibromuscular stroma was highly variable across patients and showed also high variability across the two radiologists.


Asunto(s)
Aprendizaje Profundo , Próstata , Algoritmos , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Pelvis , Próstata/diagnóstico por imagen
4.
N Engl J Med ; 378(19): 1767-1777, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29552975

RESUMEN

BACKGROUND: Multiparametric magnetic resonance imaging (MRI), with or without targeted biopsy, is an alternative to standard transrectal ultrasonography-guided biopsy for prostate-cancer detection in men with a raised prostate-specific antigen level who have not undergone biopsy. However, comparative evidence is limited. METHODS: In a multicenter, randomized, noninferiority trial, we assigned men with a clinical suspicion of prostate cancer who had not undergone biopsy previously to undergo MRI, with or without targeted biopsy, or standard transrectal ultrasonography-guided biopsy. Men in the MRI-targeted biopsy group underwent a targeted biopsy (without standard biopsy cores) if the MRI was suggestive of prostate cancer; men whose MRI results were not suggestive of prostate cancer were not offered biopsy. Standard biopsy was a 10-to-12-core, transrectal ultrasonography-guided biopsy. The primary outcome was the proportion of men who received a diagnosis of clinically significant cancer. Secondary outcomes included the proportion of men who received a diagnosis of clinically insignificant cancer. RESULTS: A total of 500 men underwent randomization. In the MRI-targeted biopsy group, 71 of 252 men (28%) had MRI results that were not suggestive of prostate cancer, so they did not undergo biopsy. Clinically significant cancer was detected in 95 men (38%) in the MRI-targeted biopsy group, as compared with 64 of 248 (26%) in the standard-biopsy group (adjusted difference, 12 percentage points; 95% confidence interval [CI], 4 to 20; P=0.005). MRI, with or without targeted biopsy, was noninferior to standard biopsy, and the 95% confidence interval indicated the superiority of this strategy over standard biopsy. Fewer men in the MRI-targeted biopsy group than in the standard-biopsy group received a diagnosis of clinically insignificant cancer (adjusted difference, -13 percentage points; 95% CI, -19 to -7; P<0.001). CONCLUSIONS: The use of risk assessment with MRI before biopsy and MRI-targeted biopsy was superior to standard transrectal ultrasonography-guided biopsy in men at clinical risk for prostate cancer who had not undergone biopsy previously. (Funded by the National Institute for Health Research and the European Association of Urology Research Foundation; PRECISION ClinicalTrials.gov number, NCT02380027 .).


Asunto(s)
Biopsia/métodos , Imagen por Resonancia Magnética , Próstata/diagnóstico por imagen , Neoplasias de la Próstata/diagnóstico por imagen , Anciano , Biopsia/efectos adversos , Estudios de Seguimiento , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Próstata/patología , Neoplasias de la Próstata/patología , Control de Calidad , Calidad de Vida , Medición de Riesgo , Encuestas y Cuestionarios , Ultrasonografía Intervencional
5.
J Urol ; 206(2): 325-337, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33835863

RESUMEN

PURPOSE: We sought to report the preliminary results of salvage high-intensity focused ultrasound for locally recurrent prostate cancer in the prostatic bed after radical prostatectomy and adjuvant or salvage radiotherapy. MATERIALS AND METHODS: We retrospectively analyzed a single-center cohort of men treated with salvage high-intensity focused ultrasound for locally recurrent prostate cancer after radical prostatectomy and adjuvant or salvage radiotherapy. All patients had a combination of choline positron emission tomography, multiparametric magnetic resonance imaging, and transrectal biopsies to confirm the local recurrence. Treatment failure was defined as persistent or recurrent prostate cancer in the prostatic bed and/or metastasis and/or introduction of systemic treatment. Progression was defined as metastasis and/or introduction of systemic treatment. Complications (Clavien-Dindo classification) and continence (Ingelman-Sundberg score) were evaluated. Kaplan-Meier analysis estimated oncological outcomes. RESULTS: Between July 2009 and November 2018, 22 patients were included; the median followup was 2.32 years. At 3 years, treatment failure-free survival rate was estimated to be 49.7% and progression-free survival rate 60.4%. Prostate specific antigen nadir ≤0.2 ng/ml was reached in 50% of the patients. A nadir of ≤0.2 ng/ml was significantly associated with better treatment failure-free and progression-free survival probabilities (p=0.003 and p=0.037, respectively). Grade III complications occurred in 6 patients (27.3%). Onset of grade II-III incontinence was significantly more frequent in cases of perianastomotic (36.4%) compared to retrovesical recurrence (0%; p=0.027). CONCLUSIONS: Salvage high-intensity focused ultrasound for locally recurrent prostate cancer after radical prostatectomy and salvage radiotherapy showed encouraging oncological results despite significant morbidity. The perianastomotic recurrence was linked to a higher risk of incontinence.


Asunto(s)
Recurrencia Local de Neoplasia/terapia , Neoplasias de la Próstata/terapia , Terapia Recuperativa , Ultrasonido Enfocado Transrectal de Alta Intensidad , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Supervivencia sin Progresión , Prostatectomía , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Radioterapia Adyuvante , Estudios Retrospectivos , Incontinencia Urinaria/etiología
6.
World J Urol ; 39(7): 2775-2781, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33175210

RESUMEN

PURPOSE: Living donor nephrectomy is a high-stake procedure involving healthy individuals, therefore every effort should be made to define each patient's individualized risk and improve potential donors' information. The aim of this study was to evaluate the interest of the Mayo adhesive probability (MAP) score, an imaging-based score initially designed to estimate the risk of adherent perinephric fat in partial nephrectomy, to predict intra- and postoperative complications of living donor nephrectomy. MATERIALS AND METHODS: We retrospectively reviewed the imaging, clinical, and follow-up data of 452 kidney donors who underwent laparoscopic donor nephrectomy in two academic centers. RESULTS: Imaging and follow-up data were available for 307 kidney donors, among which 44 (14%) had a high MAP score (≥ 3). Intraoperative difficulties were encountered in 50 patients (16%), including difficult dissection (n = 35) and bleeding (n = 17). Conversion to open surgery was required for 13 patients (4.2%). On multivariate analysis, a MAP score ≥ 3 was significantly associated with the risk of intraoperative difficulty [OR 14.12 (5.58-35.7), p < 0.001] or conversion to open surgery [OR 18.96 (3.42-105.14), p = 0.0042]. Postoperative complications were noted in 99 patients (32%), including 12 patients (3.9%) with Clavien-Dindo grade III-IV complications. On multivariate analysis, a high MAP score was also associated with the risk of postoperative complications [OR 2.55 (1.20-5.40), p = 0.01]. CONCLUSIONS: In this retrospective bicentric study, a high MAP score was associated with the risk of intra- and postoperative complications of laparoscopic donor nephrectomy. The MAP score appears of interest in the living donor evaluation process to help improve donors' information and outcomes.


Asunto(s)
Laparoscopía , Nefrectomía/efectos adversos , Nefrectomía/métodos , Recolección de Tejidos y Órganos/métodos , Adulto , Femenino , Humanos , Complicaciones Intraoperatorias , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos
7.
Lancet Oncol ; 20(1): 100-109, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30470502

RESUMEN

BACKGROUND: Whether multiparametric MRI improves the detection of clinically significant prostate cancer and avoids the need for systematic biopsy in biopsy-naive patients remains controversial. We aimed to investigate whether using this approach before biopsy would improve detection of clinically significant prostate cancer in biopsy-naive patients. METHODS: In this prospective, multicentre, paired diagnostic study, done at 16 centres in France, we enrolled patients aged 18-75 years with prostate-specific antigen concentrations of 20 ng/mL or less, and with stage T2c or lower prostate cancer. Eligible patients had been referred for prostate multiparametric MRI before a first set of prostate biopsies, with a planned interval of less than 3 months between MRI and biopsies. An operator masked to multiparametric MRI results did a systematic biopsy by obtaining 12 systematic cores and up to two cores targeting hypoechoic lesions. In the same patient, another operator targeted up to two lesions seen on MRI with a Likert score of 3 or higher (three cores per lesion) using targeted biopsy based on multiparametric MRI findings. Patients with negative multiparametric MRI (Likert score ≤2) had systematic biopsy only. The primary outcome was the detection of clinically significant prostate cancer of International Society of Urological Pathology grade group 2 or higher (csPCa-A), analysed in all patients who received both systematic and targeted biopsies and whose results from both were available for pathological central review, including patients who had protocol deviations. This study is registered with ClinicalTrials.gov, number NCT02485379, and is closed to new participants. FINDINGS: Between July 15, 2015, and Aug 11, 2016, we enrolled 275 patients. 24 (9%) were excluded from the analysis. 53 (21%) of 251 analysed patients had negative (Likert ≤2) multiparametric MRI. csPCa-A was detected in 94 (37%) of 251 patients. 13 (14%) of these 94 patients were diagnosed by systematic biopsy only, 19 (20%) by targeted biopsy only, and 62 (66%) by both techniques. Detection of csPCa-A by systematic biopsy (29·9%, 95% CI 24·3-36·0) and targeted biopsy (32·3%, 26·5-38·4) did not differ significantly (p=0·38). csPCa-A would have been missed in 5·2% (95% CI 2·8-8·7) of patients had systematic biopsy not been done, and in 7·6% (4·6-11·6) of patients had targeted biopsy not been done. Four grade 3 post-biopsy adverse events were reported (3 cases of prostatitis, and 1 case of urinary retention with haematuria). INTERPRETATION: There was no difference between systematic biopsy and targeted biopsy in the detection of ISUP grade group 2 or higher prostate cancer; however, this detection was improved by combining both techniques and both techniques showed substantial added value. Thus, obtaining a multiparametric MRI before biopsy in biopsy-naive patients can improve the detection of clinically significant prostate cancer but does not seem to avoid the need for systematic biopsy. FUNDING: French National Cancer Institute.


Asunto(s)
Biopsia Guiada por Imagen/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Adolescente , Adulto , Anciano , Humanos , Biopsia Guiada por Imagen/efectos adversos , Masculino , Persona de Mediana Edad , Imágenes de Resonancia Magnética Multiparamétrica , Estudios Prospectivos , Próstata/diagnóstico por imagen , Próstata/patología , Antígeno Prostático Específico/sangre , Ultrasonografía Intervencional , Adulto Joven
8.
BJU Int ; 124(5): 746-757, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31148367

RESUMEN

OBJECTIVES: To evaluate the oncological and functional outcomes of salvage high-intensity focused ultrasound (S-HIFU) for locally recurrent prostate cancer after low-dose-rate (LDR) brachytherapy. PATIENTS AND METHODS: Clinical phase II studies (2003-2015) included 50 consecutive patients with post-brachytherapy local recurrence treated by S-HIFU. S-HIFU was performed with post-external beam radiotherapy (EBRT) parameters and, since 2008, with specific post-brachytherapy parameters. Treatments were whole-gland ablation and, since 2009, hemi-ablation in cases of unilateral prostate cancer. The primary objective was to assess oncological outcomes: treatment failure-free survival, progression-free survival (PFS), overall survival (OS), cancer-specific survival (CSS), and metastasis-free survival (MFS) rates. The secondary objective was to evaluate adverse events, continence, and erectile function. Kaplan-Meier analysis estimated oncological outcomes. RESULTS: In all, 13 patients were treated with post-EBRT parameters, 37 with post-brachytherapy parameters, 35 with whole-gland treatment, and 15 with hemi-ablation. The median follow-up was 4.6 years. After S-HIFU, the median prostate-specific antigen level was 0.3 ng/mL. At 6 years, treatment failure-free survival, PFS, OS, CSS, and MFS rates were 41%, 45%, 93%, 98%, and 80%, respectively. Post-brachytherapy compared with post-EBRT parameters reduced Grade 2-3 incontinence (34% vs 62%, P = 0.015). Incontinence, bladder outlet obstruction and Grade ≥III complications were significantly reduced with hemi-ablation compared with whole-gland treatment (14% vs 54%, P < 0.001; 13% vs 46%, P = 0.03; 13% vs 63%, P = 0.001; respectively). Before S-HIFU, 25 patients had a five-item version of the International Index of Erectile Function score of ≥17, which was maintained in 48% at 12 months. CONCLUSION: S-HIFU for locally recurrent prostate cancer after LDR brachytherapy is associated with favourable survival rates at a price of significant morbidity. Dedicated post-brachytherapy parameters and hemi-ablation improve the safety of the treatment.


Asunto(s)
Recurrencia Local de Neoplasia , Neoplasias de la Próstata , Ultrasonido Enfocado Transrectal de Alta Intensidad , Anciano , Braquiterapia , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/terapia , Próstata/patología , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , Terapia Recuperativa/efectos adversos , Terapia Recuperativa/mortalidad , Terapia Recuperativa/estadística & datos numéricos , Resultado del Tratamiento , Ultrasonido Enfocado Transrectal de Alta Intensidad/efectos adversos , Ultrasonido Enfocado Transrectal de Alta Intensidad/mortalidad , Ultrasonido Enfocado Transrectal de Alta Intensidad/estadística & datos numéricos
9.
World J Urol ; 37(3): 409-418, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29943219

RESUMEN

CONTEXT: In recent years, focal therapy has emerged as a treatment option for a selected group of men with localized prostate cancer. Cryotherapy and high-intensity focused ultrasound (HIFU) are the most investigated types of focal treatment with other options currently under evaluation. OBJECTIVE: The objective of the study was to give a comprehensive overview of six available focal treatment options for prostate cancer with their rationale, delivery mechanism, and outcomes. INFORMATION ACQUISITION: The SIU ICUD chapter on available Energies to Treat Prostate Cancer was used as a guide to describe the different technologies. For outcomes, a literature search was conducted using PubMed key words including focal therapy, HIFU, cryotherapy, irreversible electroporation, vascular-targeted photodynamic therapy, laser interstitial therapy, radiofrequency ablation, microwave therapy, and their synonyms in MeSH terms. CONCLUSION: Focal therapy appears to have encouraging outcomes on quality of life and urinary and erectile function. For oncological outcomes, it is challenging to fully interpret the outcomes due to heterogeneity in patient selection and short-term follow-up.


Asunto(s)
Criocirugía/métodos , Electroquimioterapia/métodos , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Terapia por Láser/métodos , Fotoquimioterapia/métodos , Neoplasias de la Próstata/cirugía , Ablación por Radiofrecuencia/métodos , Humanos , Masculino , Neoplasias de la Próstata/patología
10.
J Neurosci ; 37(4): 807-819, 2017 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-28123017

RESUMEN

The brain exhibits organized fluctuations of neural activity, even in the absence of tasks or sensory input. A prominent type of such spontaneous activity is the alpha rhythm, which influences perception and interacts with other ongoing neural activity. It is currently hypothesized that states of decreased prestimulus α oscillations indicate enhanced neural excitability, resulting in improved perceptual acuity. Nevertheless, it remains debated how changes in excitability manifest at the behavioral level in perceptual tasks. We addressed this issue by comparing two alternative models describing the effect of spontaneous α power on signal detection. The first model assumes that decreased α power increases baseline excitability, amplifying the response to both signal and noise, predicting a liberal detection criterion with no effect on sensitivity. The second model predicts that decreased α power increases the trial-by-trial precision of the sensory response, resulting in improved sensitivity. We tested these models in two EEG experiments in humans where we analyzed the effects of prestimulus α power on visual detection and discrimination using a signal detection framework. Both experiments provide strong evidence that decreased α power reflects a more liberal detection criterion, rather than improved sensitivity, consistent with the baseline model. In other words, when the task requires detecting stimulus presence versus absence, reduced α oscillations make observers more likely to report the stimulus regardless of actual stimulus presence. Contrary to previous interpretations, these results suggest that states of decreased α oscillations increase the global baseline excitability of sensory systems without affecting perceptual acuity. SIGNIFICANCE STATEMENT: Spontaneous fluctuations of brain activity explain why a faint sensory stimulus is sometimes perceived and sometimes not. The prevailing view is that heightened neural excitability, indexed by decreased α oscillations, promotes better perceptual performance. Here, we provide evidence that heightened neural excitability instead reflects a state of biased perception, during which a person is more likely to see a stimulus, whether or not it is actually present. Therefore, we propose that changes in neural excitability leave the precision of sensory processing unaffected. These results establish the link between spontaneous brain activity and the variability in human perception.


Asunto(s)
Ritmo alfa/fisiología , Encéfalo/fisiología , Estimulación Luminosa/métodos , Percepción Visual/fisiología , Adulto , Electroencefalografía/métodos , Femenino , Humanos , Masculino
11.
Radiology ; 287(2): 525-533, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29361244

RESUMEN

Purpose To determine the performance of a computer-aided diagnosis (CAD) system trained at characterizing cancers in the peripheral zone (PZ) with a Gleason score of at least 7 in patients referred for multiparametric magnetic resonance (MR) imaging before prostate biopsy. Materials and Methods Two institutional review board-approved prospective databases of patients who underwent multiparametric MR imaging before prostatectomy (database 1) or systematic and targeted biopsy (database 2) were retrospectively used. All patients gave informed consent for inclusion in the databases. A CAD combining the 10th percentile of the apparent diffusion coefficient and the time to peak of enhancement was trained to detect cancers in the PZ with a Gleason score of at least 7 in 106 patients from database 1. The CAD was tested in 129 different patients from database 2. All targeted lesions were prospectively scored at biopsy by using a five-level Likert score. The CAD scores were retrospectively calculated. Biopsy results were used as the reference standard. Areas under the receiver operating characteristic curves (AUCs) were computed for CAD and Likert scores by using binormal smoothing for per-lesion and per-lobe analyses, and a density function for per-patient analysis. Results The CAD outperformed the Likert score in the overall population and all subgroups, except in the transition zone. The difference was statistically significant for the overall population (AUC, 0.95 [95% confidence interval {CI}: 0.90, 0.98] vs 0.88 [95% CI: 0.68, 0.96]; P = .02) at per-patient analysis, and for less-experienced radiologists (<1 year) at per-lesion (AUC, 0.90 [95% CI: 0.81, 0.95] vs 0.83 [95% CI: 0.73, 0.90]; P = .04) and per-lobe (AUC, 0.92 [95% CI: 0.80, 0.96] vs 0.84 [95% CI: 0.72, 0.91]; P = .04) analysis. Conclusion The CAD outperformed the Likert score prospectively assigned at biopsy in characterizing cancers with a Gleason score of at least 7. © RSNA, 2018 Online supplemental material is available for this article.


Asunto(s)
Diagnóstico por Computador , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Próstata/patología , Anciano , Área Bajo la Curva , Diagnóstico por Computador/normas , Humanos , Aumento de la Imagen , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estudios Prospectivos , Próstata/diagnóstico por imagen , Curva ROC , Sensibilidad y Especificidad
12.
BJU Int ; 119(6): 968-974, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28111893

RESUMEN

OBJECTIVE: To describe a step-by-step guide to robot-assisted anterior partial prostatectomy (RA-APP) for isolated magnetic resonance imaging (MRI)-detected anterior prostate cancer (APC). PATIENTS AND METHODS: After Institutional Review Board approval, over an 8-year period (2008-2015), 17 consenting patients were enrolled in a prospective, single-arm, single-centre, Idea, Development, Evaluation, Assessment and Long-term evaluation of innovative surgery (IDEAL) phase 2a study. The inclusion criteria comprised pre-urethral, low-intermediate risk APC diagnosed by MRI and targeted biopsies. Patient position and port placement were identical to the transperitoneal RA radical prostatectomy procedure. Three steps of dissection were identified in the following order: (i) retrograde apical, after dorsal venous plexus division, transition zone (TZ) enucleation, and distal peripheral zone (PZ) sectioning; (ii) antegrade, at the bladder neck (BN) after anterior BN sectioning, TZ enucleation up to the verumontanum; and (iii) lateral dissections, including anterolateral PZ sectioning without incision of the endopelvic fascia. We report the incidence of perioperative complications. The RA completion of prostatectomy in four cases with cancer recurrence was performed at 0.3, 2.5, 2 and 2 years, respectively. RESULTS: The RA-APP comprised en bloc excision of the anterior part of the prostate comprising of the anterior fibromuscular stroma, BN, prostate adenoma (TZ and median lobe) along with the proximal prostate urethra, PZ apical anterior horns, anterior aspect of the distal (sub-montanal) urethra, and anterior BN. The posterolateral parts of the PZ and distal (sub-montanal) urethra and peri-prostatic tissues were preserved intact. The bladder opening was sutured to the anterior sphincteric urethra wall and PZ lateral edges. The technique was feasible in all cases with no conversion to an open procedure. Perioperative complications were only Clavien-Dindo grade II. RA completion of prostatectomy was feasible in the four cases with cancer recurrence. CONCLUSION: PZ prostate-sparing RA-APP for isolated APC is feasible and safe, and represents an option for highly selected men with APCs as an alternative to other focal ablative therapy.


Asunto(s)
Prostatectomía/métodos , Neoplasias de la Próstata/cirugía , Procedimientos Quirúrgicos Robotizados , Humanos , Masculino , Guías de Práctica Clínica como Asunto , Estudios Prospectivos
13.
BJU Int ; 119(6): 896-904, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28063191

RESUMEN

OBJECTIVE: To report the oncological outcome of salvage high-intensity focused ultrasound (S-HIFU) for locally recurrent prostate cancer after external beam radiotherapy (EBRT) from a multicentre database. PATIENTS AND METHODS: This retrospective study comprises patients from nine centres with local recurrent disease after EBRT treated with S-HIFU from 1995 to 2009. The biochemical failure-free survival (bFFS) rate was based on the 'Phoenix' definition (PSA nadir + 2 ng/mL). Secondary endpoints included progression to metastasis and cancer-specific death. Kaplan-Meier analysis was performed examining overall (OS), cancer-specific (CSS) and metastasis-free survival (MFS). Adverse events and quality of life status are reported. RESULTS: In all, 418 patients with a mean (SD) follow-up of 3.5 (2.5) years were included. The mean (SD) age was 68.6 (5.8) years and the PSA level before S-HIFU was 6.8 (7.8) ng/mL. The median PSA nadir after S-HIFU was 0.19 ng/mL. The OS, CSS and MFS rates at 7 years were 72%, 82% and 81%, respectively. At 5 years the bFFS rate was 58%, 51% and 36% for pre-EBRT low-, intermediate- and high-risk patients, respectively. The 5-year bFFS rate was 67%, 42% and 22% for pre-S-HIFU PSA level ≤4, 4-10 and ≥10 ng/mL, respectively. Complication rates decreased after the introduction of specific post-RT parameters: incontinence (grade II or III) from 32% to 19% (P = 0.002); bladder outlet obstruction or stenosis from 30% to 15% (P = 0.003); recto-urethral fistula decreased from 9% to 0.6% (P < 0.001). Study limitations include being a retrospective analysis from a registry with no control group. CONCLUSION: S-HIFU for locally recurrent prostate cancer after failed EBRT is associated with 7-year CSS and MFS rates of >80% at a price of significant morbidity. S-HIFU should be initiated early following EBRT failure.


Asunto(s)
Recurrencia Local de Neoplasia/cirugía , Neoplasias de la Próstata/cirugía , Ultrasonido Enfocado Transrectal de Alta Intensidad , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Pronóstico , Neoplasias de la Próstata/radioterapia , Estudios Retrospectivos , Terapia Recuperativa , Insuficiencia del Tratamiento , Ultrasonido Enfocado Transrectal de Alta Intensidad/efectos adversos
14.
Eur Radiol ; 27(4): 1768-1775, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27436018

RESUMEN

OBJECTIVES: Our aim was to assess whether magnetic resonance imaging (MRI) features predict recurrence-free survival (RFS) after prostate cancer high-intensity focused ultrasound (HIFU) ablation. METHODS: We retrospectively selected 81 patients who underwent (i) whole-gland HIFU ablation between 2007 and 2011 as first-line therapy or salvage treatment after radiotherapy or brachytherapy, and (ii) pre- and postoperative MRI. On preoperative imaging, two senior (R1, R2) and one junior (R3) readers assessed the number of sectors invaded by the lesion with the highest Likert score (dominant lesion) using a 27-sector diagram. On postoperative imaging, readers assessed destruction of the dominant lesion using a three-level score. Multivariate analysis included the number of sectors invaded by the dominant lesion, its Likert and destruction scores, the pre-HIFU prostate-specific antigen (PSA) level, Gleason score, and the clinical setting (primary/salvage). RESULTS: The most significant predictor was the number of prostate sectors invaded by the dominant lesion for R2 and R3 (p≤0.001) and the destruction score of the dominant lesion for R1 (p = 0.011). The pre-HIFU PSA level was an independent predictor for R2 (p = 0.014), but with only marginal significance for R1 (p = 0.059) and R3 (p = 0.053). CONCLUSION: The dominant lesion's size and destruction assessed by MRI provide independent prognostic information compared with usual predictors. KEY POINTS: • The size of the MR-dominant lesion significantly influences post-HIFU recurrence-free survival. • The destruction score of the MR-dominant lesion predicts post-HIFU recurrence-free survival. • Patients with a completely devascularized MR-dominant lesion show better recurrence-free survival • Pre- and post-HIFU MRI provide prognostic information independent of usual predictors.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Neoplasias de la Próstata/terapia , Anciano , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Periodo Posoperatorio , Pronóstico , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Estudios Retrospectivos , Terapia Recuperativa/métodos , Resultado del Tratamiento , Ultrasonido Enfocado Transrectal de Alta Intensidad/métodos
15.
Eur Radiol ; 27(5): 1858-1866, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27553936

RESUMEN

OBJECTIVES: To measure benign and malignant prostate tissue stiffness using shear-wave elastography (SWE). METHODS: Thirty consecutive patients underwent transrectal SWE in the axial and sagittal planes before prostatectomy. After reviewing prostatectomy specimens, two radiologists measured stiffness in regions corresponding to cancers, lateral and median benign peripheral zone (PZ) and benign transition zone (TZ). RESULTS: Cancers were stiffer than benign PZ and TZ. All tissue classes were stiffer on sagittal than on axial imaging, in TZ than in PZ, and in median PZ than in lateral PZ. At multivariate analysis, the nature of tissue (benign or malignant; P < 0.00001), the imaging plane (axial or sagittal; P < 0.00001) and the location within the prostate (TZ, median PZ or lateral PZ; P = 0.0065) significantly and independently influenced tissue stiffness. On axial images, the thresholds maximising the Youden index in TZ, lateral PZ and median PZ were respectively 62 kPa, 33 kPa and 49 kPa. On sagittal images, the thresholds were 76 kPa, 50 kPa and 72 kPa, respectively. CONCLUSIONS: SWE can distinguish prostate malignant and benign tissues. Tissue stiffness is influenced by the imaging plane and the location within the gland. KEY POINTS: • Prostate cancers were stiffer than the benign peripheral zone • All tissue classes were stiffer on sagittal than on axial imaging • All tissue classes were stiffer in the transition zone than in the peripheral zone • All tissue classes were stiffer in the median than in the lateral peripheral zone • Taking into account imaging plane and zonal anatomy can improve cancer detection.


Asunto(s)
Próstata/diagnóstico por imagen , Hiperplasia Prostática/diagnóstico por imagen , Neoplasias de la Próstata/diagnóstico por imagen , Anciano , Diagnóstico por Imagen de Elasticidad/métodos , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Próstata/cirugía , Antígeno Prostático Específico/sangre , Prostatectomía , Hiperplasia Prostática/sangre , Hiperplasia Prostática/cirugía , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/cirugía
16.
Conscious Cogn ; 54: 89-100, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28237431

RESUMEN

Object-substitution masking (OSM) occurs when a briefly displayed target in a search array is surrounded by a mask, which remains onscreen after the target has disappeared. It has been suggested that OSM results from a specific interference with reentrant visual processing, while the initial feedforward processing is left intact. Here, we tested the prediction that the fastest saccadic responses towards a masked target, supposedly triggered before the onset of reentrant processing, are not impaired by OSM. Indeed, saccades faster than 350ms "escaped" the influence of the mask. Notably, participants' judgements of subjective awareness indicated that stimulus processing during this early stage is not entirely devoid of conscious awareness. Furthermore, the N2pc event-related potential component indicated shifts of spatial attention towards the masked targets on trials with correct fast saccades, suggesting that both target detection and spatial attention can be based on the computations accomplished during the initial feedforward sweep.


Asunto(s)
Atención/fisiología , Concienciación/fisiología , Estado de Conciencia/fisiología , Potenciales Evocados/fisiología , Reconocimiento Visual de Modelos/fisiología , Enmascaramiento Perceptual/fisiología , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Movimientos Sacádicos/fisiología , Percepción Espacial/fisiología , Adulto , Electroencefalografía , Electrooculografía , Femenino , Humanos , Masculino , Adulto Joven
17.
Neuroimage ; 125: 280-290, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26477655

RESUMEN

Primates can recognize objects embedded in complex natural scenes in a glimpse. Rapid categorization paradigms have been extensively used to study our core perceptual abilities when the visual system is forced to operate under strong time constraints. However, the neural underpinning of rapid categorization remains to be understood, and the incredible speed of sight has yet to be reconciled with modern ventral stream cortical theories of object recognition. Here we recorded multichannel subdural electrocorticogram (ECoG) signals from intermediate areas (V4/PIT) of the ventral stream of the visual cortex while monkeys were actively engaged in a rapid animal/non-animal categorization task. A traditional event-related potential (ERP) analysis revealed short visual latencies (<50-70ms) followed by a rapidly developing visual selectivity (within ~20-30ms) for most electrodes. A multi-variate pattern analysis (MVPA) technique further confirmed that reliable animal/non-animal category information was possible from this initial ventral stream neural activity (within ~90-100ms). Furthermore, this early category-selective neural activity was (a) unaffected by the presentation of a backward (pattern) mask, (b) generalized to novel (unfamiliar) stimuli and (c) co-varied with behavioral responses (both accuracy and reaction times). Despite the strong prevalence of task-related information on the neural signal, task-irrelevant visual information could still be decoded independently of monkey behavior. Monkey behavioral responses were also found to correlate significantly with human behavioral responses for the same set of stimuli. Together, the present study establishes that rapid ventral stream neural activity induces a visually selective signal subsequently used to drive rapid visual categorization and that this visual strategy may be shared between human and non-human primates.


Asunto(s)
Reconocimiento Visual de Modelos/fisiología , Corteza Visual/fisiología , Animales , Electrocorticografía , Potenciales Evocados Visuales , Macaca mulatta , Masculino
18.
Radiology ; 280(1): 117-27, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26859255

RESUMEN

Purpose To assess the intermanufacturer variability of quantitative models in discriminating cancers with a Gleason score of at least 7 among peripheral zone (PZ) lesions seen at 3-T multiparametric magnetic resonance (MR) imaging. Materials and Methods An institutional review board-approved prospective database of 257 patients who gave written consent and underwent T2-weighted, diffusion-weighted, and dynamic contrast material-enhanced imaging before prostatectomy was retrospectively reviewed. It contained outlined lesions found to be suspicious for malignancy by two independent radiologists and classified as malignant or benign after correlation with prostatectomy whole-mount specimens. One hundred six patients who underwent imaging with 3-T MR systems from two manufacturers were selected (data set A, n = 72; data set B, n = 34). Eleven parameters were calculated in PZ lesions: normalized T2-weighted signal intensity, skewness and kurtosis of T2-weighted signal intensity, T2 value, wash-in rate, washout rate, time to peak (TTP), mean apparent diffusion coefficient (ADC), 10th percentile of the ADC, and skewness and kurtosis of the histogram of the ADC values. Parameters were selected on the basis of their specificity for a sensitivity of 0.95 in diagnosing cancers with a Gleason score of at least 7, and the area under the receiver operating characteristic curve (AUC) for the models was calculated. Results The model of the 10th percentile of the ADC with TTP yielded the highest AUC in both data sets. In data set A, the AUC was 0.90 (95% confidence interval [CI]: 0.85, 0.95) or 0.89 (95% CI: 0.82, 0.94) when it was trained in data set A or B, respectively. In data set B, the AUC was 0.84 (95% CI: 0.74, 0.94) or 0.86 (95% CI: 0.76, 0.95) when it was trained in data set A or B, respectively. No third variable added significantly independent information in any data set. Conclusion The model of the 10th percentile of the ADC with TTP yielded accurate results in discriminating cancers with a Gleason score of at least 7 among PZ lesions at 3 T in data from two manufacturers. (©) RSNA, 2016 Online supplemental material is available for this article.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Anciano , Medios de Contraste , Estudios de Evaluación como Asunto , Humanos , Aumento de la Imagen , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estudios Prospectivos , Próstata/diagnóstico por imagen , Próstata/patología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
J Urol ; 206(2): 336-337, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33960824
20.
PLoS Comput Biol ; 11(9): e1004456, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26335683

RESUMEN

Observers can rapidly perform a variety of visual tasks such as categorizing a scene as open, as outdoor, or as a beach. Although we know that different tasks are typically associated with systematic differences in behavioral responses, to date, little is known about the underlying mechanisms. Here, we implemented a single integrated paradigm that links perceptual processes with categorization processes. Using a large image database of natural scenes, we trained machine-learning classifiers to derive quantitative measures of task-specific perceptual discriminability based on the distance between individual images and different categorization boundaries. We showed that the resulting discriminability measure accurately predicts variations in behavioral responses across categorization tasks and stimulus sets. We further used the model to design an experiment, which challenged previous interpretations of the so-called "superordinate advantage." Overall, our study suggests that observed differences in behavioral responses across rapid categorization tasks reflect natural variations in perceptual discriminability.


Asunto(s)
Modelos Biológicos , Reconocimiento Visual de Modelos/fisiología , Tiempo de Reacción/fisiología , Adulto , Algoritmos , Biología Computacional , Femenino , Humanos , Masculino , Análisis y Desempeño de Tareas , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA