Publications by authors named "Nagengast W"

Early detection of (pre)malignant esophageal lesions is critical to improve esophageal cancer morbidity and mortality rates. In patients with advanced esophageal adenocarcinoma (EAC) who undergo neoadjuvant chemoradiation therapy, the efficacy of therapy could be optimized and unnecessary surgery prevented by the reliable assessment of residual tumors after therapy. Optical coherence tomography (OCT) provides structural images at a (sub)-cellular level and has the potential to visualize morphological changes in tissue.

View Article and Find Full Text PDF

Purpose: Achieving endocrine remission by gross total resection is challenging in pituitary neuroendocrine tumours (PitNETs) with cavernous sinus invasion. This study aims to assess the safety, feasibility, and optimal dose for intraoperative fluorescence imaging as an added instrument to discriminate PitNET from surrounding tissue using bevacizumab-800CW, targeting vascular endothelial growth factor A (VEGF-A).

Methods: In part I, dose-escalation (0-4∙5-10-25 mg) was performed in 4 groups of 3 patients with PitNETs Knosp grade 3-4.

View Article and Find Full Text PDF

CT is the standard-of-care test for preoperative locoregional staging of colon cancer (CC) but has limited diagnostic performance. More accurate preoperative staging would guide selection among expanding patient-tailored treatment options. The purpose of this study was to evaluate through systematic review the diagnostic performance of MRI for T and N staging and that of FDG PET/CT for N staging in the locoregional staging of CC.

View Article and Find Full Text PDF
Article Synopsis
  • - The JES microvessel classification was proposed for evaluating early esophageal squamous cell neoplasia (ESCN) based on the assessment of intrapapillary capillary loops, aiming to determine eligibility for endoscopic resection in Western patients.
  • - A study analyzed 113 Western ESCN lesions with assessments from nine endoscopists of different experience levels, revealing good interobserver agreement among experts but only moderate agreement among residents-in-training.
  • - The overall accuracy of the classification was found to be low, especially among Western endoscopists and trainees, with highlighted limitations in effectively predicting invasion depth, though experienced endoscopists showed some success in identifying superficial layers without B3 vessels.
View Article and Find Full Text PDF

Objective: Meningiomas are one of the most frequently occurring brain tumors and can be curatively treated with gross-total resection. A subtotal resection increases the chances of recurrence. The intraoperative identification of invisible tumor remnants by using a fluorescent tracer targeting an upregulated biomarker could help to optimize meningioma resection.

View Article and Find Full Text PDF

Purpose: The ability to identify residual tumor tissues in patients with locally advanced esophageal cancer following neoadjuvant chemoradiotherapy (nCRT) is essential for monitoring the treatment response. Using the fluorescent tracer bevacizumab-800CW, we evaluated whether ultrasound-guided quantitative fluorescent molecular endoscopy (US-qFME), which combines quantitative fluorescence molecular endoscopy (qFME) with ultrasound-guided needle biopsy/single-fiber fluorescence (USNB/SFF), can be used to identify residual tumor tissues in patients following nCRT.

Experimental Design: Twenty patients received an additional endoscopy procedure the day before surgery.

View Article and Find Full Text PDF

Fluorescence molecular endoscopy (FME) is emerging as a "red-flag" technique with potential to deliver earlier, faster, and more personalized detection of disease in the gastrointestinal tract, including cancer, and to gain insights into novel drug distribution, dose finding, and response prediction. However, to date, the performance of FME systems is assessed mainly by endoscopists during a procedure, leading to arbitrary, potentially biased, and heavily subjective assessment. This approach significantly affects the repeatability of the procedures and the interpretation or comparison of the acquired data, representing a major bottleneck towards the clinical translation of the technology.

View Article and Find Full Text PDF

Background And Aims: Characterization of visible abnormalities in patients with Barrett's esophagus (BE) can be challenging, especially for inexperienced endoscopists. This results in suboptimal diagnostic accuracy and poor interobserver agreement. Computer-aided diagnosis (CADx) systems may assist endoscopists.

View Article and Find Full Text PDF

Objective: Improving patient selection and development of biological therapies such as vedolizumab in IBD requires a thorough understanding of the mechanism of action and target binding, thereby providing individualised treatment strategies. We aimed to visualise the macroscopic and microscopic distribution of intravenous injected fluorescently labelled vedolizumab, vedo-800CW, and identify its target cells using fluorescence molecular imaging (FMI).

Design: Forty three FMI procedures were performed, which consisted of macroscopic in vivo assessment during endoscopy, followed by macroscopic and microscopic ex vivo imaging.

View Article and Find Full Text PDF
Article Synopsis
  • Duodenoscopes, which are tools used in certain medical procedures, can spread dangerous germs that are hard to treat.
  • An investigation into patients who got sick after using the same duodenoscope found that some of them had infections caused by harmful bacteria.
  • Even though regular testing of the duodenoscope didn’t find any germs, a deeper investigation revealed that a specific part of the tool was contaminated.
View Article and Find Full Text PDF

Background & Aims: Follow-up (FU) strategies after endoscopic eradication therapy (EET) for Barrett's neoplasia do not consider the risk of mortality from causes other than esophageal adenocarcinoma (EAC). We aimed to evaluate this risk during long-term FU, and to assess whether the Charlson Comorbidity Index (CCI) can predict mortality.

Methods: We included all patients with successful EET from the nationwide Barrett registry in the Netherlands.

View Article and Find Full Text PDF
Article Synopsis
  • This study focused on the rate of residual neoplasia in patients with Barrett's neoplasia after endoscopic resection (ER) when there were confirmed tumor-positive vertical resection margins (R1v).
  • Out of 110 patients, 75% had R1v confirmed upon reassessment, and about 50% of those reviewed had residual neoplasia present.
  • The findings suggest that endoscopic reassessment 8-12 weeks post-ER can effectively identify residual neoplasia, aiding in treatment decisions for patients with R1v.
View Article and Find Full Text PDF
Article Synopsis
  • Gastrointestinal angiodysplasias are vascular abnormalities that can cause severe anemia requiring frequent blood transfusions, and octreotide has been suggested to help reduce rebleeding rates in patients.
  • A multicenter, randomized controlled trial compared the effectiveness of octreotide (40 mg every 28 days) to standard care in reducing transfusion requirements over one year for patients with this condition.
  • Results showed that patients treated with octreotide required significantly fewer transfusion units (11.0) compared to those receiving standard care (21.2), indicating that octreotide effectively reduces the need for transfusions in these patients.
View Article and Find Full Text PDF

Background: Computer-aided detection (CADe) systems could assist endoscopists in detecting early neoplasia in Barrett's oesophagus, which could be difficult to detect in endoscopic images. The aim of this study was to develop, test, and benchmark a CADe system for early neoplasia in Barrett's oesophagus.

Methods: The CADe system was first pretrained with ImageNet followed by domain-specific pretraining with GastroNet.

View Article and Find Full Text PDF

Background: Patients with cT1-2 colon cancer (CC) have a 10-20% risk of lymph node metastases. Sentinel lymph node identification (SLNi) could improve staging and reduce morbidity in future organ-preserving CC surgery. This pilot study aimed to assess safety and feasibility of robot-assisted fluorescence-guided SLNi using submucosally injected indocyanine green (ICG) in patients with cT1-2N0M0 CC.

View Article and Find Full Text PDF

Inadequate surgical margins occur frequently in oral squamous cell carcinoma surgery. Fluorescence molecular imaging (FMI) has been explored for intraoperative margin assessment, but data are limited to phase-I studies. In this single-arm phase-II study (NCT03134846), our primary endpoints were to determine the sensitivity, specificity and positive predictive value of cetuximab-800CW for tumor-positive margins detection.

View Article and Find Full Text PDF
Article Synopsis
  • * Results showed that the completeness of T-stage information improved significantly over time, but many cases still experienced misclassifications, with low sensitivity for certain tumor stages.
  • * Overall, while the ability to stage colon cancer has gotten better, inconsistencies remain, particularly in differentiating between stages, indicating the need for improved accuracy in diagnosing patients.
View Article and Find Full Text PDF

(1) Introduction: Near-infrared fluorescence (NIRF) combined with tumour-targeted tracers, such as bevacizumab-800CW, could aid surgical decision-making. This study explored the use of IRDye800CW, conjugated to bevacizumab, with four commercially available NIRF laparoscopes optimised for indocyanine green (ICG). (2) Methods: A (lymph node) phantom was made from a calibration device for NIRF and tissue-mimicking material.

View Article and Find Full Text PDF

Introduction: Endoscopic detection of early neoplasia in Barrett's esophagus is difficult. Computer Aided Detection (CADe) systems may assist in neoplasia detection. The aim of this study was to report the first steps in the development of a CADe system for Barrett's neoplasia and to evaluate its performance when compared with endoscopists.

View Article and Find Full Text PDF

Optical biopsy in Barrett's oesophagus (BE) using endocytoscopy (EC) could optimize endoscopic screening. However, the identification of dysplasia is challenging due to the complex interpretation of the highly detailed images. Therefore, we assessed whether using artificial intelligence (AI) as second assessor could help gastroenterologists in interpreting endocytoscopic BE images.

View Article and Find Full Text PDF

Esophageal adenocarcinoma causes 6% of cancer-related deaths worldwide. Near-infrared fluorescence molecular endoscopy (NIR-FME) uses a tracer that targets overexpressed proteins. In this study, we aimed to investigate the feasibility of an epidermal growth factor receptor (EGFR)-targeted tracer, cetuximab-800CW, to improve detection of early-stage esophageal adenocarcinoma.

View Article and Find Full Text PDF

Background: T1 colorectal cancer (CRC) without histological high-risk factors for lymph node metastasis (LNM) can potentially be cured by endoscopic resection, which is associated with significantly lower morbidity, mortality and costs compared to radical surgery. An important prerequisite for endoscopic resection as definite treatment is the histological confirmation of tumour-free resection margins. Incomplete resection with involved (R1) or indeterminate (Rx) margins is considered a strong risk factor for residual disease and local recurrence.

View Article and Find Full Text PDF

Background & Aims: Although random histological sampling from the esophagogastric junction (EGJ) after complete eradication of Barrett's esophagus (BE) is recommended, its clinical relevance is questionable. This study aimed to assess the incidence and long-term outcomes of findings from random EGJ biopsies in a nationwide cohort with long-term follow-up.

Methods: We included all patients with successful endoscopic eradication therapy (EET), defined as complete endoscopic eradication of all visible BE (CE-BE), for early BE neoplasia from the Dutch registry.

View Article and Find Full Text PDF

Objective: Meningiomas are frequently occurring, often benign intracranial tumors. Molecular fluorescence can be used to intraoperatively identify residual meningioma tissue and optimize safe resection; however, currently no clinically approved agent is available for this specific tumor type. In meningiomas, vascular endothelial growth factor α (VEGFα) is upregulated, and this biomarker could be targeted with bevacizumab-IRDye800CW, a fluorescent agent that is already clinically applied for the resection of other tumors and neoplasms.

View Article and Find Full Text PDF

Introduction: Despite evidence-based guidelines, variation in esophageal cancer care exists in daily practice. Many oncology networks deployed regional agreements to standardize the patient care pathway and reduce unwarranted clinical variation. The aim of this study was to explore the trends in variation of esophageal cancer care between participating hospitals of the Managed Clinical Network (MCN) in the Netherlands.

View Article and Find Full Text PDF