Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Breast Cancer Res Treat ; 202(2): 245-255, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37495799

RESUMEN

PURPOSE: The outcome of the sentinel lymph node in breast cancer patients affects adjuvant treatment. Compared to conventional histopathology, analysis by one-step nucleic acid amplification (OSNA) harvests more micrometastasis, potentially inducing overtreatment. In this study we investigated the impact of OSNA analysis on adjuvant treatment, compared to histopathological analysis. METHODS: Data from T1-3 breast cancer patients with sentinel nodes analysed between January 2016 and December 2019 by OSNA (OSNA group, n = 1086) from Zuyderland Medical Centre, the Netherlands, were compared to concurrent data from the Netherlands Cancer Registry (NKR) where sentinel nodes were examined by histology (histology group, n = 35,143). Primary outcomes were micro- or macrometastasis, axillary treatments (axillary lymph node dissection (ALND) or axillary radiotherapy (ART)), chemotherapy, and endocrine therapy. Statistics with Pearson Chi-square. RESULTS: In the OSNA group more micrometastasis (14.9%) were detected compared to the histology group (7.9%, p < 0.001). No difference in axillary treatment between groups was detected (14.3 vs. 14.4%). In case of mastectomy and macrometastasis, ALND was preferred over ART in the OSNA group (14.9%) compared to the histology group (4.4%, p < 0.001). In cases of micrometastasis, no difference was seen. There was no difference in administration of adjuvant chemotherapy between groups. Endocrine treatment was administrated less often in the OSNA group compared to the histology group (45.8% vs. 50.8%, p < 0.002). CONCLUSION: More micrometastasis were detected by OSNA compared to histopathology, but no subsequent increase in adjuvant axillary and systematic treatment was noticed. When performing mastectomy and OSNA, there was a preference for ALND compared to ART.


Asunto(s)
Neoplasias de la Mama , Ácidos Nucleicos , Ganglio Linfático Centinela , Humanos , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/terapia , Neoplasias de la Mama/patología , Ganglio Linfático Centinela/patología , Ganglios Linfáticos/patología , Biopsia del Ganglio Linfático Centinela , Micrometástasis de Neoplasia/patología , Mastectomía , Técnicas de Amplificación de Ácido Nucleico , Axila/patología , Adyuvantes Inmunológicos
2.
Eur J Nucl Med Mol Imaging ; 48(3): 721-728, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32875431

RESUMEN

PURPOSE: Visual reading of 18F-florbetapir positron emission tomography (PET) scans is used in the diagnostic process of patients with cognitive disorders for assessment of amyloid-ß (Aß) depositions. However, this can be time-consuming, and difficult in case of borderline amyloid pathology. Computer-aided pattern recognition can be helpful in this process but needs to be validated. The aim of this work was to develop, train, validate and test a convolutional neural network (CNN) for discriminating between Aß negative and positive 18F-florbetapir PET scans in patients with subjective cognitive decline (SCD). METHODS: 18F-florbetapir PET images were acquired and visually assessed. The SCD cohort consisted of 133 patients from the SCIENCe cohort and 22 patients from the ADNI database. From the SCIENCe cohort, standardized uptake value ratio (SUVR) images were computed. From the ADNI database, SUVR images were extracted. 2D CNNs (axial, coronal and sagittal) were built to capture features of the scans. The SCIENCe scans were randomly divided into training and validation set (5-fold cross-validation), and the ADNI scans were used as test set. Performance was evaluated based on average accuracy, sensitivity and specificity from the cross-validation. Next, the best performing CNN was evaluated on the test set. RESULTS: The sagittal 2D-CNN classified the SCIENCe scans with the highest average accuracy of 99% ± 2 (SD), sensitivity of 97% ± 7 and specificity of 100%. The ADNI scans were classified with a 95% accuracy, 100% sensitivity and 92.3% specificity. CONCLUSION: The 2D-CNN algorithm can classify Aß negative and positive 18F-florbetapir PET scans with high performance in SCD patients.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedad de Alzheimer/diagnóstico por imagen , Compuestos de Anilina , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Glicoles de Etileno , Humanos , Redes Neurales de la Computación , Tomografía de Emisión de Positrones
3.
Eur J Nucl Med Mol Imaging ; 48(2): 340-349, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32737518

RESUMEN

PURPOSE: Quantitative prostate-specific membrane antigen (PSMA) PET analysis may provide for non-invasive and objective risk stratification of primary prostate cancer (PCa) patients. We determined the ability of machine learning-based analysis of quantitative [18F]DCFPyL PET metrics to predict metastatic disease or high-risk pathological tumor features. METHODS: In a prospective cohort study, 76 patients with intermediate- to high-risk PCa scheduled for robot-assisted radical prostatectomy with extended pelvic lymph node dissection underwent pre-operative [18F]DCFPyL PET-CT. Primary tumors were delineated using 50-70% peak isocontour thresholds on images with and without partial-volume correction (PVC). Four hundred and eighty standardized radiomic features were extracted per tumor. Random forest models were trained to predict lymph node involvement (LNI), presence of any metastasis, Gleason score ≥ 8, and presence of extracapsular extension (ECE). For comparison, models were also trained using standard PET features (SUVs, volume, total PSMA uptake). Model performance was validated using 50 times repeated 5-fold cross-validation yielding the mean receiver-operator characteristic curve AUC. RESULTS: The radiomics-based machine learning models predicted LNI (AUC 0.86 ± 0.15, p < 0.01), nodal or distant metastasis (AUC 0.86 ± 0.14, p < 0.01), Gleason score (0.81 ± 0.16, p < 0.01), and ECE (0.76 ± 0.12, p < 0.01). The highest AUCs reached using standard PET metrics were lower than those of radiomics-based models. For LNI and metastasis prediction, PVC and a higher delineation threshold improved model stability. Machine learning pre-processing methods had a minor impact on model performance. CONCLUSION: Machine learning-based analysis of quantitative [18F]DCFPyL PET metrics can predict LNI and high-risk pathological tumor features in primary PCa patients. These findings indicate that PSMA expression detected on PET is related to both primary tumor histopathology and metastatic tendency. Multicenter external validation is needed to determine the benefits of using radiomics versus standard PET metrics in clinical practice.


Asunto(s)
Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata , Humanos , Aprendizaje Automático , Masculino , Estudios Prospectivos , Neoplasias de la Próstata/diagnóstico por imagen , Medición de Riesgo
4.
Breast Cancer Res Treat ; 156(3): 465-472, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27013474

RESUMEN

Triple-negative breast cancer is associated with early recurrence and low survival rates. Several trials investigate the safety of a more conservative approach of axillary treatment in clinically T1-2N0 breast cancer. Triple-negative breast cancer comprises only 15 % of newly diagnosed breast cancers, which might result in insufficient power for representative results for this subgroup. We aimed to provide a nationwide overview on the occurrence of (regional) recurrences in triple-negative breast cancer patients with a clinically T1-2N0 status. For this cohort study, 2548 women diagnosed between 2005 and 2008 with clinically T1-2N0 triple-negative breast cancer were selected from the Netherlands Cancer Registry. Follow-up data until 2014 were analyzed using Kaplan-Meier. Sentinel lymph node biopsy was performed in 2486 patients, and (completion) axillary lymph node dissection in 562 patients. Final pathologic nodal status was pN0 in 78.5 %, pN1mi in 4.5 %, pN1 in 12.3 %, pN2-3 in 3.6 %, and pNx in 1.1 %. During a follow-up of 5 years, regional recurrence occurred in 2.9 %, local recurrence in 4.2 % and distant recurrence in 12.2 %. Five-year disease-free survival was 78.7 %, distant disease-free survival 80.5 %, and 5-year overall survival 82.3 %. Triple-negative clinically T1-2N0 breast cancer patients rarely develop a regional recurrence. Their disease-free survival is more threatened by distant recurrence, affecting their overall survival. Consequently, it seems justified to include triple-negative breast cancer patients in randomized controlled trials investigating the safety of minimizing axillary staging and treatment.


Asunto(s)
Axila/cirugía , Escisión del Ganglio Linfático/estadística & datos numéricos , Recurrencia Local de Neoplasia/epidemiología , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Axila/patología , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Países Bajos , Sistema de Registros , Medición de Riesgo , Biopsia del Ganglio Linfático Centinela/estadística & datos numéricos , Análisis de Supervivencia , Adulto Joven
5.
Lab Invest ; 95(7): 833-42, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25867767

RESUMEN

Current genome-wide methods to detect DNA-methylation in healthy and diseased tissue require high-quality DNA from fresh-frozen (FF) samples. However, well-annotated clinical samples are mostly available as formalin-fixed, paraffin-embedded (FFPE) tissues containing poor-quality DNA. To overcome this limitation, we here aimed to evaluate a DNA restoration protocol for usage with the genome-wide Infinium HumanMethylation450 BeadChip assay (HM-450K). Sixty-six DNA samples from normal colon (n=9) and breast cancer (n=11) were interrogated separately using HM-450K. Analyses included matched FF/FFPE samples and technical duplicates. FFPE DNA was processed with (FFPEr) or without a DNA restoration protocol (Illumina). Differentially methylated genes were finally validated in 24 additional FFPE tissues using nested methylation-specific PCR (MSP). In summary, ß-values correlation between FFPEr duplicates was high (ρ=0.9927 (s.d. ±0.0015)). Matched FF/FFPEr correlation was also high (ρ=0.9590 (s.d. ±0.0184)) compared with matched FF/FFPE (ρ=0.8051 (s.d. ±0.1028). Probe detection rate in FFPEr samples (98.37%, s.d. ±0.66) was comparable to FF samples (99.98%, s.d. ±0.019) and substantially lower in FFPE samples (82.31%, s.d. ±18.65). Assay robustness was not decreased by sample archival age up to 10 years. We could also demonstrate no decrease in assay robustness when using 100 ng of DNA input only. Four out of the five selected differentially methylated genes could be validated by MSP. The gene failing validation by PCR showed high variation of CpG ß-values in primer-binding sites. In conclusion, by using the FFPE DNA restoration protocol, HM-450K assays provide robust, accurate and reproducible results with FFPE tissue-derived DNA, which are comparable to those obtained with FF tissue. Most importantly, differentially methylated genes can be validated using more sensitive techniques, such as nested MSP, altogether providing an epigenomics platform for molecular pathological epidemiology research on archived samples with limited tissue amount.


Asunto(s)
Metilación de ADN , Epigenómica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos , Adhesión en Parafina , Fijación del Tejido , Análisis por Conglomerados , Fluorescencia , Formaldehído , Humanos , Reproducibilidad de los Resultados
6.
Oncologist ; 20(8): 856-63, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26099745

RESUMEN

BACKGROUND: The impact of drug prescriptions in real life as opposed to strict clinical trial prescription is only rarely assessed, although it is well recognized that incorrect use may harm patients and may have a significant impact on health care resources. We investigated the use and effectiveness of adjuvant trastuzumab in daily practice compared with the effectiveness in clinical trials. METHODS: We included all patients with stage I-III invasive breast cancer, irrespective of human epidermal growth factor receptor 2 (HER2) status, diagnosed in five hospitals in the southeast of The Netherlands in 2005-2007. We aimed to assess the actual use of adjuvant trastuzumab in early HER2-positive breast and its efficacy in daily practice. RESULTS: Of 2,684 patients included, 476 (17.7%) had a HER2-positive tumor. Of these, 251 (52.7%) patients had an indication for trastuzumab treatment of which 196 (78.1%) patients actually received it. Of the 225 patients without an indication, 34 (15.1%) received trastuzumab. Five-year disease-free survival was 80.7% for (n = 230) patients treated with versus 68.2% for (n = 246) patients not treated with trastuzumab (p = .0023), and 5-year overall survival rates were 90.7% and 77.4%, respectively (p = .0002). The hazard ratio for disease recurrence was 0.63 (95% confidence interval, 0.37-1.06) for trastuzumab when adjusting for potential confounders. CONCLUSION: This study shows that in real life, patients treated with trastuzumab in early-stage HER2-positive breast cancer had a 5-year disease-free and overall survival comparable to prior randomized trials. For informative decision making, real-life data are of additional value, providing insight on outcome of patients considered ineligible for treatment.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Trastuzumab/uso terapéutico , Adulto , Anciano , Antineoplásicos/administración & dosificación , Quimioterapia Adyuvante , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad , Países Bajos , Trastuzumab/administración & dosificación
7.
Radiology ; 275(2): 345-55, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25513854

RESUMEN

PURPOSE: To evaluate the diagnostic performance of unenhanced axillary T2-weighted and diffusion-weighted (DW) magnetic resonance (MR) imaging for axillary nodal staging in patients with newly diagnosed breast cancer, with node-by-node and patient-by-patient validation. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. Fifty women (mean age, 60 years; range, 22-80 years) underwent high-spatial-resolution axillary 3.0-T T2-weighted imaging without fat suppression and DW imaging (b = 0, 500, and 800 sec/mm(2)), followed by either sentinel lymph node biopsy (SLNB) or axillary lymph node dissection. Two radiologists independently scored each lymph node on a confidence level scale from 0 (benign) to 4 (malignant), first on T2-weighted MR images, then on DW MR images. Two researchers independently measured the mean apparent diffusion coefficient (ADC) of each lymph node. Diagnostic performance parameters were calculated on the basis of node-by-node and patient-by-patient validation. RESULTS: With respective node-by-node and patient-by-patient validation, T2-weighted MR imaging had a specificity of 93%-97% and 87%-95%, sensitivity of 32%-55% and 50%-67%, negative predictive value (NPV) of 88%-91% and 86%-89%, positive predictive value (PPV) of 60%-70% and 62%-75%, and area under the receiver operating characteristic curve (AUC) of 0.78 and 0.80-0.88, with good interobserver agreement (κ = 0.70). The addition of DW MR imaging resulted in lower specificity (59%-88% and 50%-84%), higher sensitivity (45%-64% and 75%-83%), comparable NPV (89% and 90%-91%), lower PPV (23%-42% and 34%-60%), and lower AUC (0.68-0.73 and 0.70-0.86). ADC measurement resulted in a specificity of 63%-64% and 61%-63%, sensitivity of 41% and 67%, NPV of 85% and 85%-86%, PPV of 18% and 35%-36%, and AUC of 0.54-0.58 and 0.69-0.74, respectively, with excellent interobserver agreement (intraclass correlation coefficient, 0.83). CONCLUSION: Dedicated high-spatial-resolution axillary T2-weighted MR imaging showed good specificity on the basis of node-by-node and patient-by-patient validation, with good interobserver agreement. However, its NPV is still insufficient to substitute it for SLNB for exclusion of axillary lymph node metastasis. DW MR imaging and ADC measurement were of no added value.


Asunto(s)
Neoplasias de la Mama/patología , Imagen por Resonancia Magnética , Adulto , Anciano , Anciano de 80 o más Años , Axila , Imagen de Difusión por Resonancia Magnética/estadística & datos numéricos , Femenino , Humanos , Metástasis Linfática , Imagen por Resonancia Magnética/estadística & datos numéricos , Persona de Mediana Edad , Estadificación de Neoplasias , Variaciones Dependientes del Observador , Estudios Prospectivos , Adulto Joven
8.
Pediatr Res ; 76(3): 261-8, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24956227

RESUMEN

BACKGROUND: Gut immaturity is linked with postnatal intestinal disorders. However, biomarkers to assess the intestinal developmental stage around birth are lacking. The aim of this study was to gain more insight on intestinal fatty acid-binding protein (I-FABP) as an indicator of gut maturity. METHODS: Antenatal I-FABP distribution and release was investigated in extremely premature, moderately premature, and term lambs, and these findings were verified in human urinary samples. Ileal I-FABP distribution was confirmed in autopsy material within 24 h postnatally. RESULTS: Median (range) serum I-FABP levels were lower in extremely premature lambs compared with moderately premature lambs (156 (50.0-427) vs. 385 (100-1,387) pg/ml; P = 0.02). Contrarily, median early postnatal urine I-FABP levels in human infants were higher in extremely premature compared with moderately premature and term neonates (1,219 (203-15,044) vs. 256 (50-1,453) and 328 (96-1,749) pg/ml; P = 0.008 and P = 0.04, respectively). I-FABP expression was most prominent in nonvacuolated enterocytes and increased with rising gestational age (GA) in ovine and human tissue samples. The epithelial distribution pattern changed from a phenotype displaying I-FABP-positive enterocytes merely in the crypts early in gestation into a phenotype with I-FABP expressing cells exclusively present in the villus tips at term in ovine and human tissue. CONCLUSION: In this ovine and human study, increasing GA is accompanied by an increase in I-FABP tissue content. Cord I-FABP levels correlate with gestation in ovine fetuses, identifying I-FABP as a marker for gut maturation. Raised postnatal urine I-FABP levels in preterm human infants may indicate intestinal injury and/or inflammation in utero.


Asunto(s)
Proteínas de Unión a Ácidos Grasos/metabolismo , Íleon/metabolismo , Mucosa Intestinal/metabolismo , Animales , Animales Recién Nacidos , Autopsia , Biomarcadores/metabolismo , Enterocitos/metabolismo , Proteínas de Unión a Ácidos Grasos/sangre , Proteínas de Unión a Ácidos Grasos/orina , Femenino , Sangre Fetal/metabolismo , Edad Gestacional , Humanos , Íleon/citología , Íleon/crecimiento & desarrollo , Recien Nacido Extremadamente Prematuro , Mucosa Intestinal/citología , Mucosa Intestinal/crecimiento & desarrollo , Masculino , Morfogénesis , Fenotipo , Nacimiento Prematuro , Ovinos
9.
Breast Cancer Res ; 15(2): R29, 2013 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-23566419

RESUMEN

INTRODUCTION: Cyclooxygenase-2 (COX-2) is frequently over-expressed in primary breast cancer. In transgenic breast cancer models, over-expression of COX-2 leads to tumour formation while COX-2 inhibition exerts anti-tumour effects in breast cancer cell lines. To further determine the effect of COX-2 inhibition in primary breast cancer, we aimed to identify transcriptional changes in breast cancer tissues of patients treated with the selective COX-2 inhibitor celecoxib. METHODS: In a single-centre double-blind phase II study, thirty-seven breast cancer patients were randomised to receive either pre-operative celecoxib (400 mg) twice daily for two to three weeks (n = 22) or a placebo according to the same schedule (n = 15). Gene expression in fresh-frozen pre-surgical biopsies (before treatment) and surgical excision specimens (after treatment) was profiled by using Affymetrix arrays. Differentially expressed genes and altered pathways were bioinformatically identified. Expression of selected genes was validated by quantitative PCR (qPCR). Immunohistochemical protein expression analyses of the proliferation marker Ki-67, the apoptosis marker cleaved caspase-3 and the neo-angiogenesis marker CD34 served to evaluate biological response. RESULTS: We identified 972 and 586 significantly up- and down-regulated genes, respectively, in celecoxib-treated specimens. Significant expression changes in six out of eight genes could be validated by qPCR. Pathway analyses revealed over-representation of deregulated genes in the networks of proliferation, cell cycle, extracellular matrix biology, and inflammatory immune response. The Ki-67 mean change relative to baseline was -29.1% (P = 0.019) and -8.2% (P = 0.384) in the treatment and control arm, respectively. Between treatment groups, the change in Ki-67 was statistically significant (P = 0.029). Cleaved caspase-3 and CD34 expression were not significantly different between the celecoxib-treated and placebo-treated groups. CONCLUSIONS: Short-term COX-2 inhibition by celecoxib induces transcriptional programs supporting anti-tumour activity in primary breast cancer tissue. The impact on proliferation-associated genes is reflected by a reduction of Ki-67 positive cells. Therefore, COX-2 inhibition should be considered as a treatment strategy for further clinical testing in primary breast cancer. TRIAL REGISTRATION: ClinicalTrials.gov NCT01695226.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Inhibidores de la Ciclooxigenasa/uso terapéutico , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Pirazoles/uso terapéutico , Sulfonamidas/uso terapéutico , Biomarcadores de Tumor , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patología , Carcinoma Lobular/tratamiento farmacológico , Carcinoma Lobular/genética , Carcinoma Lobular/patología , Celecoxib , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Clasificación del Tumor , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
10.
J Surg Case Rep ; 2023(7): rjad419, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37485497

RESUMEN

Metachronous colorectal cancer is relatively rare, occurring in 0.7-3.6% of patients diagnosed with colorectal adenocarcinoma. Cutaneous metastases are similarly a rare presentation, occurring in <6% of metastatic colorectal cancer patients. Even more rare are the cutaneous recurrences at the peristomal site. Clinically, it is difficult to distinguish between metachronous cancer and cutaneous metastases. This paper reports a case of an elderly woman presenting with a slowly progressing peristomal cutaneous lesion 16 years after surgical resection for colorectal cancer. Core punch biopsy revealed a cutaneous localization of an intestinal type of adenocarcinoma. A surgical resection of the peristomal area was carried out whereby a new colostomy was created on the contralateral side. Definite histopathological examination showed a superficially located intestinal type adenocarcinoma with extensive pagetoid spread in the epidermal surface. In conclusion, it is important to remain alert and strive for early detection for cutaneous abnormalities following colorectal cancer.

11.
Front Med (Lausanne) ; 10: 1180773, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37250654

RESUMEN

Rational: Deep learning (DL) has demonstrated a remarkable performance in diagnostic imaging for various diseases and modalities and therefore has a high potential to be used as a clinical tool. However, current practice shows low deployment of these algorithms in clinical practice, because DL algorithms lack transparency and trust due to their underlying black-box mechanism. For successful employment, explainable artificial intelligence (XAI) could be introduced to close the gap between the medical professionals and the DL algorithms. In this literature review, XAI methods available for magnetic resonance (MR), computed tomography (CT), and positron emission tomography (PET) imaging are discussed and future suggestions are made. Methods: PubMed, Embase.com and Clarivate Analytics/Web of Science Core Collection were screened. Articles were considered eligible for inclusion if XAI was used (and well described) to describe the behavior of a DL model used in MR, CT and PET imaging. Results: A total of 75 articles were included of which 54 and 17 articles described post and ad hoc XAI methods, respectively, and 4 articles described both XAI methods. Major variations in performance is seen between the methods. Overall, post hoc XAI lacks the ability to provide class-discriminative and target-specific explanation. Ad hoc XAI seems to tackle this because of its intrinsic ability to explain. However, quality control of the XAI methods is rarely applied and therefore systematic comparison between the methods is difficult. Conclusion: There is currently no clear consensus on how XAI should be deployed in order to close the gap between medical professionals and DL algorithms for clinical implementation. We advocate for systematic technical and clinical quality assessment of XAI methods. Also, to ensure end-to-end unbiased and safe integration of XAI in clinical workflow, (anatomical) data minimization and quality control methods should be included.

12.
EJNMMI Res ; 13(1): 88, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37758869

RESUMEN

BACKGROUND: Convolutional neural networks (CNNs), applied to baseline [18F]-FDG PET/CT maximum intensity projections (MIPs), show potential for treatment outcome prediction in diffuse large B-cell lymphoma (DLBCL). The aim of this study is to investigate the robustness of CNN predictions to different image reconstruction protocols. Baseline [18F]FDG PET/CT scans were collected from 20 DLBCL patients. EARL1, EARL2 and high-resolution (HR) protocols were applied per scan, generating three images with different image qualities. Image-based transformation was applied by blurring EARL2 and HR images to generate EARL1 compliant images using a Gaussian filter of 5 and 7 mm, respectively. MIPs were generated for each of the reconstructions, before and after image transformation. An in-house developed CNN predicted the probability of tumor progression within 2 years for each MIP. The difference in probabilities per patient was then calculated between both EARL2 and HR with respect to EARL1 (delta probabilities or ΔP). We compared these to the probabilities obtained after aligning the data with ComBat using the difference in median and interquartile range (IQR). RESULTS: CNN probabilities were found to be sensitive to different reconstruction protocols (EARL2 ΔP: median = 0.09, interquartile range (IQR) = [0.06, 0.10] and HR ΔP: median = 0.1, IQR = [0.08, 0.16]). Moreover, higher resolution images (EARL2 and HR) led to higher probability values. After image-based and ComBat transformation, an improved agreement of CNN probabilities among reconstructions was found for all patients. This agreement was slightly better after image-based transformation (transformed EARL2 ΔP: median = 0.022, IQR = [0.01, 0.02] and transformed HR ΔP: median = 0.029, IQR = [0.01, 0.03]). CONCLUSION: Our CNN-based outcome predictions are affected by the applied reconstruction protocols, yet in a predictable manner. Image-based harmonization is a suitable approach to harmonize CNN predictions across image reconstruction protocols.

13.
Ned Tijdschr Geneeskd ; 1672023 11 15.
Artículo en Holandés | MEDLINE | ID: mdl-37994718

RESUMEN

BACKGROUND: Animal bite wounds are common and can cause serious hand infections. Risk factors not only include the oral flora of the animal and the anatomy of the teeth, but also the comorbidities of the bitten patient. CASE DESCRIPTION: In this case report we describe a 46-years old female patient with comorbidities, including diabetes mellitus type 2 and peripheral artery disease, suffering a fulminant hand infection after a domestic rat bite with the newly described bacterium Rodentibacterratti. Despite extensive antibiotic therapy and surgical debridement, a ray amputation was inevitable to maintain adequate hand function. CONCLUSION: Infections after animal bites may be caused by a variety of pathogens. The pathogen Rodentibacterratti has not previously been associated with infections in humans and future research is indicated to assess therapeutic strategies. Patients should be referred to a (plastic) surgeon if there is no clinical improvement within 48 hours of initiating antibiotic treatment.


Asunto(s)
Mordeduras y Picaduras , Diabetes Mellitus Tipo 2 , Animales , Ratas , Humanos , Femenino , Persona de Mediana Edad , Mordeduras y Picaduras/complicaciones , Antibacterianos/uso terapéutico , Factores de Riesgo , Desbridamiento , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico
14.
Sci Rep ; 13(1): 13111, 2023 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-37573446

RESUMEN

Convolutional neural networks (CNNs) may improve response prediction in diffuse large B-cell lymphoma (DLBCL). The aim of this study was to investigate the feasibility of a CNN using maximum intensity projection (MIP) images from 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) baseline scans to predict the probability of time-to-progression (TTP) within 2 years and compare it with the International Prognostic Index (IPI), i.e. a clinically used score. 296 DLBCL 18F-FDG PET/CT baseline scans collected from a prospective clinical trial (HOVON-84) were analysed. Cross-validation was performed using coronal and sagittal MIPs. An external dataset (340 DLBCL patients) was used to validate the model. Association between the probabilities, metabolic tumour volume and Dmaxbulk was assessed. Probabilities for PET scans with synthetically removed tumors were also assessed. The CNN provided a 2-year TTP prediction with an area under the curve (AUC) of 0.74, outperforming the IPI-based model (AUC = 0.68). Furthermore, high probabilities (> 0.6) of the original MIPs were considerably decreased after removing the tumours (< 0.4, generally). These findings suggest that MIP-based CNNs are able to predict treatment outcome in DLBCL.


Asunto(s)
Fluorodesoxiglucosa F18 , Linfoma de Células B Grandes Difuso , Humanos , Inteligencia Artificial , Linfoma de Células B Grandes Difuso/diagnóstico por imagen , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/metabolismo , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Ensayos Clínicos como Asunto
15.
Schizophr Res ; 262: 132-141, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37950936

RESUMEN

BACKGROUND: Prediction of treatment resistance in schizophrenia (TRS) would be helpful to reduce the duration of ineffective treatment and avoid delays in clozapine initiation. We applied machine learning to identify clinical, sociodemographic, familial, and environmental variables that are associated with TRS and could potentially predict TRS in the future. STUDY DESIGN: Baseline and follow-up data on trait(-like) variables from the Genetic Risk and Outcome of Psychosis (GROUP) study were used. For the main analysis, we selected patients with non-affective psychotic disorders who met TRS (n = 200) or antipsychotic-responsive criteria (n = 423) throughout the study. For a sensitivity analysis, we only selected patients who met TRS (n = 76) or antipsychotic-responsive criteria (n = 123) at follow-up but not at baseline. Random forest models were trained to predict TRS in both datasets. SHapley Additive exPlanation values were used to examine the variables' contributions to the prediction. STUDY RESULTS: Premorbid functioning, age at onset, and educational degree were most consistently associated with TRS across both analyses. Marital status, current household, intelligence quotient, number of moves, and family loading score for substance abuse also consistently contributed to the prediction of TRS in the main or sensitivity analysis. The diagnostic performance of our models was modest (area under the curve: 0.66-0.69). CONCLUSIONS: We demonstrate that various clinical, sociodemographic, familial, and environmental variables are associated with TRS. Our models only showed modest performance in predicting TRS. Prospective large multi-centre studies are needed to validate our findings and investigate whether the model's performance can be improved by adding data from different modalities.


Asunto(s)
Antipsicóticos , Clozapina , Trastornos Psicóticos , Esquizofrenia , Humanos , Antipsicóticos/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/genética , Esquizofrenia/diagnóstico , Estudios Prospectivos , Clozapina/uso terapéutico , Trastornos Psicóticos/tratamiento farmacológico , Trastornos Psicóticos/genética
16.
Diagnostics (Basel) ; 12(3)2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35328149

RESUMEN

Acquisition time and injected activity of 18F-fluorodeoxyglucose (18F-FDG) PET should ideally be reduced. However, this decreases the signal-to-noise ratio (SNR), which impairs the diagnostic value of these PET scans. In addition, 89Zr-antibody PET is known to have a low SNR. To improve the diagnostic value of these scans, a Convolutional Neural Network (CNN) denoising method is proposed. The aim of this study was therefore to develop CNNs to increase SNR for low-count 18F-FDG and 89Zr-antibody PET. Super-low-count, low-count and full-count 18F-FDG PET scans from 60 primary lung cancer patients and full-count 89Zr-rituximab PET scans from five patients with non-Hodgkin lymphoma were acquired. CNNs were built to capture the features and to denoise the PET scans. Additionally, Gaussian smoothing (GS) and Bilateral filtering (BF) were evaluated. The performance of the denoising approaches was assessed based on the tumour recovery coefficient (TRC), coefficient of variance (COV; level of noise), and a qualitative assessment by two nuclear medicine physicians. The CNNs had a higher TRC and comparable or lower COV to GS and BF and was also the preferred method of the two observers for both 18F-FDG and 89Zr-rituximab PET. The CNNs improved the SNR of low-count 18F-FDG and 89Zr-rituximab PET, with almost similar or better clinical performance than the full-count PET, respectively. Additionally, the CNNs showed better performance than GS and BF.

17.
Ann Med Surg (Lond) ; 71: 102924, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34703587

RESUMEN

INTRODUCTION: and importance: The caesarean section is a widely spread procedure and 29.7 million times performed every year inn 169 countries in the world. Overall, complications are seen in 6% for elective caesarean to 15% for emergency caesarean. CASE PRESENTATION: We here report a case which was initially diagnosed as a postoperative paralytic ileus. After a complicated caesarean section caused by bleeding and problems with haemostasis, a healthy child was born with full mother recovery for the first 24 hours after surgery. Unfortunately, her condition deteriorated between 24 and 48 hours and she reported progressive nausea and painful bloating. Laboratory tests and CT imaging showed progressive signs of inflammation and distention of the caecum and colon. A second CT scan the next day revealed signs of perforation. An ileocecal resection was performed with a primary anastomosis. Full recovery occurred two weeks later. CLINICAL DISCUSSION: With an estimated incidence of only 0,08%, bowel perforations due to caesarean section, are rare. Moreover, is the clinical presentation diverse and computed topography is essential during the diagnostic process. To avoid potential morbidity and mortality, the surgeon must consider performing a laparotomy in case of a deteriorating patient in non-invasive treatment fails. CONCLUSION: Caecal perforation must be considered as complication after a caesarean section. An ileocecal resection is necessary in this situation. This case report shows that a primary anastomosis is a possible option in a healthy patient that is hemodynamically stable during the operation. In case of an unhealthy or hemodynamic unstable patient, the safest option is a temporary ileostomy.

18.
Mol Imaging Biol ; 23(4): 550-559, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33443720

RESUMEN

PURPOSE: The simplified reference tissue model (SRTM) is commonly applied for the quantification of brain positron emission tomography (PET) studies, particularly because it avoids arterial cannulation. SRTM requires a validated reference region which is obtained by baseline-blocking or displacement studies. Once a reference region is validated, the use should be verified for each new subject. This verification normally requires volume of distribution (VT) of a reference region. However, performing dynamic scanning and arterial sampling is not always possible, specifically in elderly subjects and in advanced disease stages. The aim of this study was to investigate the use of non-invasive standardised uptake value (SUV) approaches, in comparison to VT, as a verification of the previously validated grey matter cerebellum reference region for [18F]flortaucipir and [18F]florbetapir PET imaging in Alzheimer's disease (AD) patients and controls. PROCEDURES: Dynamic 130-min [18F]flortaucipir PET scans obtained from nineteen subjects (10 AD patients) and 90-min [18F]florbetapir dynamic scans obtained from fourteen subjects (8 AD patients) were included. Regional VT's were estimated for both tracers and were considered the standard verification of the previously validated reference region. Non-invasive SUVs corrected for body weight (SUVBW), lean body mass (SUL), and body surface area (SUVBSA) were obtained by using later time intervals of the dynamic scans. Simulations were also performed to assess the effect of flow and specific binding (BPND) on the SUVs. RESULTS: A low SUV corresponded well with a low VT for both [18F]flortaucipir and [18F]florbetapir. Simulation confirmed that SUVs were only slightly affected by flow changes and that increases in SUV were predominantly determined by the presence of specific binding. CONCLUSIONS: In situations where dynamic scanning and arterial sampling is not possible, a low SUV(80-100 min) for [18F]flortaucipir and a low SUV(50-70 min) for [18F]florbetapir may be used as indication for absence of specific binding in the grey matter cerebellum reference region.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Compuestos de Anilina/química , Encéfalo/diagnóstico por imagen , Carbolinas/química , Radioisótopos de Flúor/farmacocinética , Tomografía de Emisión de Positrones/métodos , Tiazoles/química , Anciano , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Compuestos de Anilina/farmacocinética , Encéfalo/metabolismo , Encéfalo/patología , Carbolinas/farmacocinética , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos/farmacocinética , Tiazoles/farmacocinética , Distribución Tisular , Proteínas tau/química
20.
Obstet Gynecol Surv ; 75(6): 369-380, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32603475

RESUMEN

IMPORTANCE: The introduction of the cardiotocogram (CTG) during labor has not been found to improve neonatal outcome. The search for a more reliable, less invasive, and patient-friendly technique is ongoing. The noninvasive fetal electrocardiogram (NI-fECG) has been proposed as one such alternative. OBJECTIVES: The aim of this study was to review the literature on the performance of NI-fECG for fetal monitoring during labor. Following the PRISMA guidelines, a systematic search in MEDLINE, EMBASE, and Cochrane Library was performed. Studies involving original research investigating the performance of NI-fECG during labor were included. Animal studies and articles in languages other than English, Dutch, or German were excluded. The QUADAS-2 checklist was used for quality assessment. A descriptive analysis of the results is provided. RESULTS: Eight articles were included. Pooled analysis of the results of the separate studies was not possible due to heterogeneity. All studies demonstrate that it is possible to apply NI-fECG during labor. Compared with Doppler ultrasound, NI-fECG performs equal or better in most studies. CONCLUSIONS AND RELEVANCE: NI-fECG for fetal monitoring is a promising noninvasive and patient-friendly technique that provides accurate information. Future studies should focus on signal quality throughout labor, with the aim to further optimize technical development of NI-fECG.


Asunto(s)
Electrocardiografía/métodos , Corazón Fetal/fisiología , Frecuencia Cardíaca Fetal , Femenino , Humanos , Trabajo de Parto , Embarazo , Reproducibilidad de los Resultados , Relación Señal-Ruido
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA