Publications by authors named "Alexander L Vahrmeijer"

Purpose: Assessment of tissue perfusion using near-infrared fluorescence (NIR) with indocyanine green (ICG) is gaining popularity, however reliable and objective interpretation remains a challenge. Therefore, this study aimed to establish reference curves for vital tissue perfusion across target tissues using this imaging modality.

Methods: Data from five prospective study cohorts conducted in three Dutch academic medical centres between December 2018 and June 2023 was included.

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  • The study aimed to validate simpler methods for measuring [Ga]Ga-FAPI-46 uptake by comparing them to comprehensive pharmacokinetic modeling.
  • Ten patients with pancreatobiliary cancer participated in a 90-minute dynamic PET/CT scan, and various methods, including plasma-input tissue-compartment models, were used to assess the uptake of the compound in lesions.
  • The results indicated that image-based target-to-whole blood ratio (TBR) and mean standardized uptake values (SUVmean) at 60-70 minutes post-injection are effective and reliable for quantifying [Ga]Ga-FAPI-46 uptake.
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Introduction: Accurate staging of malignancies often requires comprehensive evaluation of lymph nodes. However, finding these lymph nodes during oncological surgery is a daunting and time-consuming task, which increases the risk of missed lymph nodes and complications. Near-infrared (NIR) fluorescence imaging with the experimental fluorescent contrast agent PanLN800(-Forte) could provide real-time identification of lymph nodes and may solve this longstanding problem.

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  • - Oesophageal cancer patients achieving a clinical complete response (CR) after neoadjuvant chemoradiotherapy (nCRT) may benefit from active surveillance; however, identifying true CRs is difficult due to a 40% regrowth rate in these patients.
  • - The study examined pre-treatment and post-treatment tissue samples to analyze the expression of several tumor markers (CEA, EpCAM, VEGF-α, EGFR, c-MET) through immunohistochemistry, aiming to find markers for potential near-infrared fluorescence imaging.
  • - Results showed high expression of EpCAM in adenocarcinomas and EGFR in squamous cell carcinomas, while neoadjuvant therapy did not alter the
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Purpose: Tumor-targeted positron emission tomography (PET) and fluorescence-guided surgery (FGS) could address current challenges in pre- and intraoperative imaging of gastric cancer. Adequate selection of molecular imaging targets remains crucial for successful tumor visualization. This study evaluated the potential of integrin αβ, carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), epidermal growth factor receptor (EGFR), epithelial cell adhesion molecule (EpCAM) and human epidermal growth factor receptor-2 (HER2) for molecular imaging of primary gastric cancer, as well as lymph node and distant metastases.

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Background: The use of fluorescence agents and imaging systems is a promising adjunct in the surgical management of colorectal cancer. This systematic review and meta-analysis aimed to assess the safety and efficacy of fluorescence-guided surgery in the management of colorectal cancer, with a comparison to conventional (non-fluorescence-guided) surgery.

Methods: A literature search of MEDLINE, Embase, Emcare, and CINAHL databases was performed for studies that reported data on the outcomes of fluorescence-guided surgery, with or without a comparison group undergoing conventional surgery, for colorectal cancer between January 2000 and January 2024.

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  • * A new imaging agent, AKRO-6qcICG, can be applied to the surface of these tumors and helps surgeons see where cancer cells remain during surgery using near-infrared fluorescence.
  • * In studies with patients, AKRO-6qcICG showed excellent sensitivity (100%) in detecting remaining cancer cells, indicating it could be a valuable tool to improve surgical outcomes and minimize additional treatments.
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Surgical intervention for endometriosis is an important treatment modality, yet incomplete resection resulting from poor visibility of affected tissue and consequently recurrence of disease remains a prevalent challenge. Intra-operative visualization of endometriosis, enabling fluorescence-guided surgery (FGS), could help to optimize surgical treatment. A biomarker, upregulated in endometriosis compared to adjacent tissue, is required to use as a target for FGS.

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Purpose: Cysteine cathepsins are proteases that play a role in normal cellular physiology and neoplastic transformation. Elevated expression and enzymatic activity of cathepsins in breast cancer (BCa) indicates their potential as a target for tumor imaging. In particular cathepsin B (CTSB), L (CTSL), and S (CTSS) are used as targets for near-infrared (NIR) fluorescence imaging (FI), a technique that allows real-time intraoperative tumor visualization and resection margin assessment.

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  • The study investigates the use of folate receptor (FR)-targeted PET/CT imaging with [F]fluoro-PEG-folate for better preoperative assessment in advanced-stage epithelial ovarian cancer (EOC), aiming to enhance selection for cytoreductive surgery (CRS) and reduce unnecessary procedures.
  • It evaluates the safety and tolerability of [F]fluoro-PEG-folate through vital sign monitoring and adverse event recording, along with quantifying disease burden using the Peritoneal Cancer Index (PCI) score from imaging and surgical findings.
  • The study was halted early after including eight patients, revealing that while [F]fluoro-PEG-folate was safe
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  • The study investigates the use of fluorescence imaging (FLI) to enhance the surgical identification of oral and laryngeal cancers (OSCC and LSCC) and papillary thyroid carcinoma (PTC), aiming to improve excision precision due to challenges in tumor delineation.
  • Six potential tumor-targeting markers were evaluated through immunohistochemical staining in various cancer samples, with integrin αvβ6 and EGFR showing significant overexpression in OSCC and LSCC, indicating their effectiveness as FLI targets.
  • The research suggests that although PTC shows lower expressions of these markers, the notable overexpression of VEGF-α and c-Met could also make them viable for improving
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Background: Patients with lower extremity arterial disease (LEAD) frequently require revascularization procedures. Currently used diagnostic methods are insufficient in predicting successful outcomes and focus on macrovascular rather than microvascular state. Several promising modalities to increase diagnostic accuracy are emerging, including maximal systolic acceleration (ACC), measured by duplex ultrasound (DUS).

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Background: Anastomotic leakage is a severe postoperative complication in colorectal surgery and compromised bowel perfusion is considered a major contributing factor. Conventional methods to assess bowel perfusion have a low predictive value for anastomotic leakage. We therefore aimed to evaluate the efficacy of real-time assessment with near-infrared (NIR) fluorescence imaging with indocyanine green (ICG) in the prevention of anastomotic leakage.

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Introduction: Diabetes Mellitus (DM) is a common chronic disease, affecting 435 million people globally. Impaired vasculature in DM patients leads to complications like lower extremity arterial disease (LEAD) and foot ulcers, often resulting in amputations. DM causes additional peripheral neuropathy leading to multifactorial wound problems.

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  • Achieving complete tumor removal is difficult, but can be enhanced using real-time fluorescence-guided surgery with specially designed molecular probes.
  • The traditional process of identifying and testing these probes is lengthy and complicated by the variation within tumors and between different patients.
  • To address these challenges, researchers created a multispectral real-time 3D imaging platform that uses organoid technology to better mimic the diversity in patient tumors and how probes bind to healthy tissue.
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Purpose: To describe the pharmacokinetic properties of the [F]fluoro-polyethylene glycol(PEG)-folate radiotracer in PET/CT imaging of patients with advanced stage epithelial ovarian cancer (EOC).

Procedures: In five patients with advanced EOC (FIGO stage IIIB/IIIC, Fédération Internationale de Gynécologie et d'Obstétrique), a 90-min dynamic PET acquisition of the pelvis was performed directly after i.v.

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Importance: Unintended tumor-positive resection margins occur frequently during minimally invasive surgery for colorectal liver metastases and potentially negatively influence oncologic outcomes.

Objective: To assess whether indocyanine green (ICG)-fluorescence-guided surgery is associated with achieving a higher radical resection rate in minimally invasive colorectal liver metastasis surgery and to assess the accuracy of ICG fluorescence for predicting the resection margin status.

Design, Setting, And Participants: The MIMIC (Minimally Invasive, Indocyanine-Guided Metastasectomy in Patients With Colorectal Liver Metastases) trial was designed as a prospective single-arm multicenter cohort study in 8 Dutch liver surgery centers.

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This review summarizes the key applications of a hybrid operating room (HOR) in hepatobiliary surgery and explores the advantages, limitations, and future directions of its utilization. A comprehensive literature search was conducted in PubMed to identify articles reporting on the utilization of HORs in liver surgery. So far, the HOR has been limitedly applied in hepatobiliary surgery.

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Background: Colon cancer is a heterogeneous disease and consists of various molecular subtypes. Despite advances in high-throughput expression profiling, limitations remain in predicting clinical outcome and assigning specific treatment to individual cases. Tumor-immune interactions play a critical role, with tumors that activate the immune system having better outcome for the patient.

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  • Near-infrared fluorescence imaging in cancer surgery currently lacks a consistent method to assess the effectiveness of fluorescent dyes, leading to challenges in translating research findings from lab to clinical settings.
  • The goal of this study is to create a semi-automatic method that provides an objective way to measure fluorescent signals in tissue samples post-surgery.
  • The new method was tested and showed better consistency than traditional techniques, indicating it can enhance the reliability and standardization of studies involving fluorescent dyes in clinical applications.
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Currently there is a global lack of consensus about the best treatment for asymptomatic congenital pulmonary airway malformation (CPAM) patients. The somatic KRAS mutations commonly found in adult lung cancer combined with mucinous proliferations are sometimes found in CPAM. For this risk of developing malignancy, 70% of paediatric surgeons perform a resection for asymptomatic CPAM.

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The surgical resection of solid tumours can be enhanced by fluorescence-guided imaging. However, variable tumour uptake and incomplete clearance of fluorescent dyes reduces the accuracy of distinguishing tumour from normal tissue via conventional fluorescence intensity-based imaging. Here we show that, after systemic injection of the near-infrared dye indocyanine green in patients with various types of solid tumour, the fluorescence lifetime (FLT) of tumour tissue is longer than the FLT of non-cancerous tissue.

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Purpose: Fluorescence-guided surgery (FGS) can play a key role in improving radical resection rates by assisting surgeons to gain adequate visualization of malignant tissue intraoperatively. Designed ankyrin repeat proteins (DARPins) possess optimal pharmacokinetic and other properties for in vivo imaging. This study aims to evaluate the preclinical potential of epithelial cell adhesion molecule (EpCAM)-binding DARPins as targeting moieties for near-infrared fluorescence (NIRF) and photoacoustic (PA) imaging of cancer.

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  • Metastasectomy is a treatment for colorectal lung metastases (CLM), and this study explored using a fluorescent tracer, SGM-101, to improve detection during surgery.
  • The study involved 13 patients and measured how effectively SGM-101 indicated the presence of CLM, with the closed-field imaging showing the best results in identifying tumors.
  • Ultimately, the findings suggest that SGM-101 has potential for enhancing the surgical targeting of tumors, especially when combined with better imaging technologies and patient selection strategies.
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