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Abstract Achieving complete tumor resection is challenging and can be improved by real-time fluorescence-guided surgery with molecular-targeted probes. However, pre-clinical identification and validation of probes presents a lengthy process that is traditionally performed in animal models and further hampered by inter- and intra-tumoral heterogeneity in target expression. To screen multiple probes at patient scale, we developed a multispectral real-time 3D imaging platform that implements organoid technology to effectively model patient tumor heterogeneity and, importantly, healthy human tissue binding.

Growth of malignant cells in solid tumors induces changes to the tumor microenvironment (TME). These changes result in promotion of tumor growth, invasion, and metastasis, but also in tumor resistance to drugs and radiotherapy. The enhanced permeability and retention (EPR) effect in neo-angiogenic tumor tissue enables the transport of therapeutic molecules from the circulation into the tumor, but studies show that further diffusion of these agents is often not sufficient for efficient tumor eradication. Despite the hyperpermeable vasculature facilitating the delivery of drugs and tracers, the high density of stromal cells and matrix proteins, in combination with the elevated interstitial fluid pressure in the microenvironment of solid tumors, presents a barrier which limits the delivery of compounds to the core of the tumor. Reversing the cancer-cell-induced changes to the microenvironment as well as novel nanoparticle strategies to circumvent tumor-induced stromal changes have therefore been suggested as potential methods to improve the delivery of therapeutic molecules and drug efficacy. Strategies to modulate the TME, i.e., normalization of tumor vasculature and depletion of excessive stromal proteins and cells, show promising results in enhancing delivery of therapeutic compounds. Modulation of the TME may therefore enhance the efficacy of current cancer treatments and facilitate the development of novel treatment methods as an alternative for invasive resection procedures.

BackgroundColon 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. The localization of T cells within tumor epithelium, to enable direct contact, is essential for antitumor function, but bulk DNA/RNA sequencing data lacks spatial distribution information. In this study, we provide spatial T cell tumor distribution and connect these data with previously determined genomic data in the AC-ICAM colon cancer patient cohort.MethodsColon cancer patients (n=90) with transcriptome data available were selected. We used a custom multiplex immunofluorescence assay on colon tumor tissue sections for quantifying T cell subsets spatial distribution in the tumor microenvironment, in terms of cell number, location, mutual distance, and distance to tumor cells. Statistical analyses included the previously determined Immunologic Constant of Rejection (ICR) transcriptome correlation and patient survival, revealing potential prognostic value in T cell spatial distribution.ResultsT cell phenotypes were characterized and CD3+CD8-FoxP3- T cells were found to be the predominant tumor-infiltrating subtype while CD3+FoxP3+ T cells and CD3+CD8+ T cells showed similar densities. Spatial distribution analysis elucidated that proliferative T cells, characterized by Ki67 expression, and Granzyme B-expressing T cells were predominantly located within the tumor epithelium. We demonstrated an increase in immune cell density and a decrease in the distance of CD3+CD8+ T cells to the nearest tumor cell, in the immune active, ICR High, immune subtypes. Higher densities of stromal CD3+FoxP3+ T cells showed enhanced survival outcomes, and patients exhibited superior clinical benefits when greater spatial distances were observed between CD3+CD8-FoxP3- or CD3+CD8+ T cells and CD3+FoxP3+ T cells.ConclusionOur study’s in-depth analysis of the spatial distribution and densities of major T cell subtypes within the tumor microenvironment has provided valuable information that paves the way for further research into the intricate relationships between immune cells and colon cancer development.

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. In order to stratify these patients into high- and low-risk groups for developing malignancy, a minimally invasive diagnostic method is needed, for example targeted molecular imaging. A prerequisite for this technique is a cell membrane bound target. The aim of this study was to review the literature to identify potential targets for molecular imaging in CPAM patients and perform a first step to validate these findings. A systematic search was conducted to identify possible targets in CPAM and adenocarcinoma in situ (AIS) patients. The most interesting targets were evaluated with immunofluorescent staining in adjacent lung tissue, KRAS+ CPAM tissue and KRAS– CPAM tissue. In 185 included studies, 143 possible targets were described, of which 20 targets were upregulated and membrane-bound. Six of them were also upregulated in lung AIS tissue (CEACAM5, E-cadherin, EGFR, ERBB2, ITGA2 and MUC1) and as such of possible interest. Validating studies showed that MUC1 is a potential interesting target. This study provides an extensive overview of all known potential targets in CPAM that might identify those patients at risk for malignancy and conducted the first step towards validation, identifying MUC1 as the most promising target.

BackgroundThe diagnostic process of patients with suspect pancreatic lesions is often lengthy and prone to repeated diagnostic procedures due to inconclusive results. Targeted Next-Generation Sequencing (NGS) performed on cytological material obtained with fine needle aspiration (FNA) or biliary duct brushing can speed up this process. Here, we study the incremental value of NGS for establishing the correct diagnosis, and subsequent treatment plan in patients with inconclusive diagnosis after regular diagnostic work-up for suspect pancreatic lesions.MethodsIn this prospective cross-sectional cohort study, patients were screened for inclusion in four hospitals. NGS was performed with AmpliSeq Cancer Hotspot Panel v2 and v4b in patients with inconclusive cytology results or with an uncertain diagnosis. Diagnostic results were evaluated by the oncology pancreatic multidisciplinary team. The added value of NGS was determined by comparing diagnosis (malignancy, cystic lesion or benign condition) and proposed treatment plan (exploration/resection, neoadjuvant chemotherapy, follow-up, palliation or repeated FNA) before and after integration of NGS results. Final histopathological analysis or a 6-month follow-up period were used as the reference standard in case of surgical intervention or non-invasive treatment, respectively.ResultsIn 50 of the 53 included patients, cytology material was sufficient for NGS analysis. Diagnosis before and after integration of NGS results differed in 24% of the patients. The treatment plan was changed in 32% and the diagnosis was substantiated by the NGS data in 44%. Repetition of FNA/brushing was prevented in 14% of patients. All changes in treatment plan were correctly made after integration of NGS. Integration of NGS increased overall diagnostic accuracy from 68% to 94%.InterpretationThis study demonstrates the incremental diagnostic value of NGS in patients with an initial inconclusive diagnosis. Integration of NGS results can prevent repeated EUS/FNA, and can also rigorously change the final diagnosis and treatment plan.

Introduction Anastomotic leakage (AL) is one of the major complications after colorectal surgery. Compromised tissue perfusion at the anastomosis site increases the risk of AL. Several cohort studies have shown that indocyanine green (ICG) combined with fluorescent near-infrared imaging is a feasible and reproducible technique for real-time intraoperative imaging of tissue perfusion, leading to reduced leakage rates after colorectal resection. Unfortunately, these studies were not randomised. Therefore, we propose a randomised controlled trial to assess the value of ICG-guided surgery in reducing AL after colorectal surgery.Methods and analysis A multicentre, randomised controlled clinical trial will be conducted to assess the benefit of ICG-guided surgery in preventing AL. A total of 978 patients scheduled for colorectal surgery will be included. Patients will be randomised between the Fluorescence Guided Bowel Anastomosis group and the Conventional Bowel Anastomosis group. The primary endpoint is clinically relevant AL (defined as requiring active therapeutic intervention or reoperation) within 90 days after surgery. Among the secondary endpoints are 30-day clinically relevant AL, all-cause postoperative complications, all-cause and AL-related mortality, surgical and non-surgical reinterventions, total surgical time, length of hospital stay and all-cause and AL-related readmittance.Ethics and dissemination This protocol has been approved by the Medical Ethical Committee Leiden-Den Haag-Delft (METC-LDD) and is registered at ClinicalTrials.gov and trialregister.nl. The results of this study will be reported through peer-reviewed publications and conference presentations.Trial registration number NCT04712032; NL7502.

Background Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy in need of effective (immuno)therapeutic treatment strategies. For the optimal application and development of cancer immunotherapies, a comprehensive understanding of local and systemic immune profiles in patients with PDAC is required. Here, our goal was to decipher the interplay between local and systemic immune profiles in treatment-naïve patients with PDAC.Methods The immune composition of PDAC, matched non-malignant pancreatic tissue, regional lymph nodes, spleen, portal vein blood, and peripheral blood samples (collected before and after surgery) from 11 patients with PDAC was assessed by measuring 41 immune cell markers by single-cell mass cytometry. Furthermore, the activation potential of tumor-infiltrating lymphocytes as determined by their ability to produce cytokines was investigated by flow cytometry. In addition, the spatial localization of tumor-infiltrating innate lymphocytes in the tumor microenvironment was confirmed by multispectral immunofluorescence.Results We found that CD103+CD8+ T cells with cytotoxic potential are infrequent in the PDAC immune microenvironment and lack the expression of activation markers and checkpoint blockade molecule programmed cell death protein-1 (PD-1). In contrast, PDAC tissues showed a remarkable increased relative frequency of B cells and regulatory T cells as compared with non-malignant pancreatic tissues. Besides, a previously unappreciated innate lymphocyte cell (ILC) population (CD127–CD103+CD39+CD45RO+ ILC1-like) was discovered in PDAC tissues. Strikingly, the increased relative frequency of B cells and regulatory T cells in pancreatic cancer samples was reflected in matched portal vein blood samples but not in peripheral blood, suggesting a regional enrichment of immune cells that infiltrate the PDAC microenvironment. After surgery, decreased frequencies of myeloid dendritic cells were found in peripheral blood.Conclusions Our work demonstrates an immunosuppressive landscape in PDAC tissues, generally deprived of cytotoxic T cells and enriched in regulatory T cells and B cells. The antitumor potential of ILC1-like cells in PDAC may be exploited in a therapeutic setting. Importantly, immune profiles detected in blood isolated from the portal vein reflected the immune cell composition of the PDAC microenvironment, suggesting that this anatomical location could be a source of tumor-associated immune cell subsets.

Objectives:. The aim of this study was to determine the potential benefit of perioperative systemic therapy on overall and progression-free survival after repeat local treatment in patients suffering from recurrent colorectal cancer liver metastasis (CRLM). Background:. The optimal treatment strategy in patients with recurrent CRLM needs to be clarified, in particular for those suffering from early recurrence of CRLM. Methods:. In this multicenter observational cohort study, consecutive patients diagnosed with recurrent CRLM between 2009 and 2019 were retrospectively identified in 4 academic liver surgery centers. Disease-free interval after initial local treatment of CRLM was categorized into recurrence within 6, between 6 and 12, and after 12 months. Perioperative systemic therapy consisted of induction, (neo)adjuvant, or combined regimens. Overall and progression-free survival after repeat local treatment of CRLM were analyzed by multivariable Cox regression analyses, resulting in adjusted hazard ratios (aHRs). Results:. Out of 303 patients included for analysis, 90 patients received perioperative systemic therapy for recurrent CRLM. Favorable overall (aHR, 0.45; 95% confidence interval [CI], 0.26–0.75) and progression-free (aHR, 0.53; 95% CI, 0.35–0.78) survival were observed in patients with a disease-free interval of more than 12 months. No significant difference in overall and progression-free survival was observed in patients receiving perioperative systemic therapy at repeat local treatment of CRLM, stratified for disease-free interval, previous exposure to chemotherapy, and RAS mutation status. Conclusions:. No benefit of perioperative systemic therapy was observed in overall and progression-free survival after repeat local treatment of recurrent CRLM.

Molecular fluorescence-guided surgery using near-infrared light has the potential to improve the rate of complete resection of cancer. Typically, monoclonal antibodies are being used as targeting moieties, however smaller fragments, such as single-domain antibodies (i.e., Nanobodies®) improve tumor specificity and enable tracer injection on the same day as surgery. In this study, the feasibility of a carcinoembryonic antigen-targeting Nanobody (NbCEA5) conjugated to two zwitterionic dyes (ZW800-1 Forte [ZW800F] and ZW800-1) for visualization of pancreatic ductal adenocarcinoma (PDAC) was investigated. After site-specific conjugation of NbCEA5 to the zwitterionic dyes, binding specificity was evaluated on human PDAC cell lines with flow cytometry. A dose escalation study was performed for both NbCEA5-ZW800F and NbCEA5-ZW800-1 in mice with subcutaneously implanted pancreatic tumors. Fluorescence imaging was performed up to 24 h after intravenous injection. Furthermore, the optimal dose for NbCEA5-ZW800-1 was injected in mice with orthotopically implanted pancreatic tumors. A dose-escalation study showed superior mean fluorescence intensities for NbCEA5-ZW800-1 compared to NbCEA5-ZW800F. In the orthotopic tumor models, NbCEA5-ZW800-1 accumulated specifically in pancreatic tumors with a mean in vivo tumor-to-background ratio of 2.4 (SD = 0.23). This study demonstrated the feasibility and potential advantages of using a CEA-targeted Nanobody conjugated to ZW800-1 for intraoperative PDAC imaging.

Introduction: Myxofibrosarcoma (MFS) is the most common soft-tissue sarcoma subtype in elderly patients. Local recurrence (LR) remains a major concern as the lack of intraoperative guidance and an infiltrative growth pattern with long, slender tails hamper surgeons’ ability to achieve adequate resection margins for MFS. Fluorescence-guided surgery (FGS) could overcome this concern by delineating tumor tissue during surgery. One of the most important steps to successful FGS is to define a tumor-specific biomarker that is highly overexpressed in tumor tissue while low or absent in adjacent healthy tissue. The aim of this study is to evaluate the expression of eight previously selected promising biomarkers for FGS in MFS tissue samples with adjacent healthy tissue using immunohistochemistry (IHC). Methods: The following eight biomarkers were stained in seventeen paraffin-embedded MFS samples: tumor endothelial marker-1 (TEM-1, also known as endosialin/CD248), vascular endothelial growth factor receptor-1 (VEGFR-1, also known as Flt-1), vascular endothelial growth factor receptor-2 (VEGFR-2, also known as Flk1), vascular endothelial growth factor-A (VEGF-A), epidermal growth factor receptor (EGFR), insulin-like growth factor-1 receptor (IGF-1R), platelet derived growth factor receptor-α (PDGFR-α), and cluster of differentiation 40 (CD40, also known as TNFRSF5). A pathologist specializing in sarcoma annotated the margin between the tumor and adjacent healthy tissue in each MFS tissue sample. Subsequently, we used an objective IHC scoring method to assess and compare the difference in staining intensity between the tumor and adjacent healthy tissue, which is crucial for the use of FGS. Results: TEM-1, VEGF-A, and PDGFR-α stained all MFS tumors, while the other biomarkers did not show expression in all MFS tumors. Ultimately, TEM-1 was identified as the most suitable biomarker for FGS in MFS based on higher tumor-to-background (TBR) staining intensity compared to VEGF-A and PDGFR-α, regardless of preoperative therapy. Conclusion: TEM-1-targeted FGS tracers should be further investigated to optimize MFS treatment.

A series of mono- and bis-polyethylene glycol (PEG)-substituted BF2-azadipyrromethene fluorophores have been synthesized with emissions in the near-infrared region (700–800 nm) for the purpose of fluorescence guided intraoperative imaging; chiefly ureter imaging. The Bis-PEGylation of fluorophores resulted in higher aqueous fluorescence quantum yields, with PEG chain lengths of 2.9 to 4.6 kDa being optimal. Fluorescence ureter identification was possible in a rodent model with the preference for renal excretion notable through comparative fluorescence intensities from the ureters, kidneys and liver. Ureteral identification was also successfully performed in a larger animal porcine model under abdominal surgical conditions. Three tested doses of 0.5, 0.25 and 0.1 mg/kg all successfully identified fluorescent ureters within 20 min of administration which was sustained up to 120 min. 3-D emission heat map imaging allowed the spatial and temporal changes in intensity due to the distinctive peristaltic waves of urine being transferred from the kidneys to the bladder to be identified. As the emission of these fluorophores could be spectrally distinguished from the clinically-used perfusion dye indocyanine green, it is envisaged that their combined use could be a step towards intraoperative colour coding of different tissues.

PurposePercutaneous hepatic perfusion with melphalan (M-PHP) is increasingly used in patients with liver metastases from various primary tumors, yet data on colorectal liver metastases (CRLM) are limited. The aim of this study was to prospectively evaluate the efficacy and safety of M-PHP in patients with CRLM.Materials and methodsProspective, single-center, single-arm phase II study of M-PHP with hemofiltration in patients with unresectable CRLM. Proven, extrahepatic metastatic disease was one of the exclusion criteria. Primary outcomes were overall response rate (ORR) and best overall response (BOR). Secondary outcomes were overall survival (OS), progression-free survival (PFS), hepatic PFS (hPFS), and safety.ResultsA total of 14 M-PHP procedures were performed in eight patients between March 2014 and December 2015. All patients (median age 56 years, ranging from 46 to 68) had received (extensive) systemic chemotherapy before entering the study. The ORR was 25.0%, with two out of eight patients showing partial response as BOR. Median OS was 17.3 months (ranging from 2.6 to 30.9) with a one-year OS of 50.0%. Median PFS and hPFS were 4.4 and 4.5 months, respectively. No serious adverse events occurred. Grade 3/4 hematologic adverse events were observed in the majority of patients, though all were transient and well-manageable.ConclusionM-PHP is a safe procedure with only limited efficacy in patients with unresectable CRLM who already showed progression of disease after receiving one or more systemic treatment regimens.

PURPOSEIn patients undergoing percutaneous liver perfusion with melphalan (M-PHP), the presence of variant hepatic arteries (HAs) may require catheter repositioning and thus prolong procedure time. Coil-embolization of variant HAs may enable M-PHP with a single catheter position as occlusion of variant HAs results in redistribution of flow through preexisting intrahepatic arterial collaterals. We aimed to evaluate whether redistribution of flow has any negative effect on therapeutic response in ocular melanoma patients undergoing M-PHP.METHODSWe retrospectively analyzed pretreatment angiograms in all 32 patients that underwent M-PHP between January 2014 and March 2017 for unresectable liver metastases from ocular melanoma. Patients that underwent embolization of a variant left HA (LHA) or middle HA (MHA) during pretreatment angiography followed by at least one technically successful M-PHP were included for further analysis. Redistribution of arterial flow was evaluated on angiography and cone-beam computed tomography (CBCT) images. In each patient, tumor response in liver segments with redistributed blood flow was evaluated using RECIST 1.1 and mRECIST, and then compared with tumor response in segments without flow redistribution. Follow-up scans were reviewed to evaluate progression of liver metastases.RESULTSA total of 12 patients were included. Replaced LHA embolization resulted in redistribution of flow to segment(s) 2 (n=3), 2 and 3 (n=5), and 2, 3 and 4 (n=2). MHA embolization resulted in redistribution of flow to segment 4 (n=2). Successful redistribution was confirmed by angiography and/or CBCT in all patients. Tumor response was similar for redistributed and non-redistributed liver segments in 8 out of 9 patients (89%) according to RECIST 1.1, and in 7 out of 8 patients (88%) according to mRECIST. In three patients, tumor response was not evaluable according to RECIST 1.1 or mRECIST as metastases were too small to be categorized as target lesions (n=1), or target lesions were confined to non-redistributed segments (n=2). In one patient, tumor response was not evaluable according to mRECIST as target lesions in the redistributed segments were hypovascular. After a median follow-up time of 17.1 months (range, 9.1–38.5 months), hepatic progression was seen in 9 out of 12 patients with a median time to progression of 9.9 months (range, 2.5–17.7 months). Progression of liver metastases was never seen only in the redistributed liver segments.CONCLUSIONFlow redistribution in liver segments by coil-embolization of variant HAs is a feasible technique that does not seem to compromise tumor response in patients undergoing M-PHP.

Abstract Background Combining modalities using dual-labeled antibodies may allow preoperative and intraoperative tumor localization and could be used in image-guided surgery to improve complete tumor resection. Trastuzumab is a monoclonal antibody against the human epidermal growth factor-2 (HER2) receptor and dual-labeled trastuzumab with both a fluorophore (IRDye800CW) and a radioactive label (111In) can be used for multimodal imaging of HER2-positive breast cancer. The aim of this study was to demonstrate the feasibility of HER2-targeted multimodal imaging using [111In]In-DTPA-trastuzumab-IRDye800CW in an orthotopic breast cancer model. Methods Trastuzumab was conjugated with p-isothiocyanatobenzyl (ITC)-diethylenetriaminepentaacetic acid (DTPA) and IRDye800CW-NHS ester and subsequently labeled with 111In. In a dose escalation study, the biodistribution of 10, 30, and 100 μg [111In]In-DTPA-trastuzumab-IRDye800CW was determined 48 h after injection in BALB/c nude mice with orthotopic high HER2-expressing tumors. Also, a biodistribution study was performed in a low HER2-expressing breast cancer model. In addition, multimodal image-guided surgery was performed in each group. Autoradiography, fluorescence microscopy, and immunohistochemically stained slices of the tumors were compared for co-localization of tumor tissue, HER2 expression, fluorescence, and radiosignal. Results Based on the biodistribution data, a 30 μg dose of dual-labeled trastuzumab (tumor-to-blood ratio 13 ± 2) was chosen for all subsequent studies. [111In]In-DTPA-trastuzumab-IRDye800CW specifically accumulated in orthotopic HER2-positive BT474 tumors (101 ± 7 %IA/g), whereas uptake in orthotopic low HER2-expressing MCF7 tumor was significantly lower (1.2 ± 0.2 %IA/g, p = 0.007). BT474 tumors could clearly be visualized with both micro-SPECT/CT, fluorescence imaging and subsequently, image-guided resection was performed. Immunohistochemical analyses of BT474 tumors demonstrated correspondence in fluorescence, radiosignal, and high HER2 expression. Conclusions Dual-labeled trastuzumab showed specific accumulation in orthotopic HER2-positive BT474 breast tumors with micro-SPECT/CT and fluorescence imaging and enabled image-guided tumor resection. In the clinical setting, [111In]In-DTPA-trastuzumab-IRDye800CW could be valuable for preoperative detection of (metastatic) tumors by SPECT/CT imaging, and intraoperative localization by using a gamma probe and fluorescence image-guided surgery to improve radical resection of tumor tissue in patients with HER2-positive tumors.

Abstract Background Post cholecystectomy syndrome is characterized as recurrence of symptoms as experienced before cholecystectomy. In rare cases, a remnant cystic duct is causing these symptoms and occasionally surgical resection is performed. During surgery, visualization of the biliary ducts could be difficult due to inflammation and dense adhesions. Case presentation In this article, we presented a 36-year old woman with post-cholecystectomy syndrome in which we evaluated the feasibility of near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) for visualization of the remnant cystic and common bile duct during robot-assisted surgery. Intraoperative visualization of the remnant biliary duct and other important structures was feasible, and resection of the remnant cystic duct was successfully performed under fluorescence guidance, without any complications. Conclusions NIR fluorescence imaging of the biliary ducts using ICG does not prolong the operating time, and could potentially decrease the operation time in difficult procedures, because of easy and fast detection of the biliary tract. Furthermore, it is a non-hazardous and non-invasive technique, as it does not require use of radiation and cannot cause bile duct injury. This case illustrated that ICG NIR fluorescence imaging during difficult robot-assisted surgical procedures of the bile ducts is effective and therefore highly recommended.

Iatrogenic injury of the ureters is a feared complication of laparoscopic abdominal surgery. Here the authors present the NIR fluorophore ZW800-1 as an intraoperative imaging agent for ureter mapping, showing its safety, pharmacokinetic properties, and efficacy in healthy volunteers and patients undergoing abdominopelvic surgery.

Assessing lymph node (LN) status during tumor resection is fundamental for the staging of colorectal cancer. Current guidelines require a minimum of 12 LNs to be harvested during resection and ultra-staging regional lymph nodes by sentinel lymph node (SLN) assessment is being extensively investigated. The current study presents novel near-infrared (NIR) fluorescent dyes for simultaneous pan lymph node (PanLN; regional) and SLN mapping. PanLN-Forte was intravenously injected in mice and assessed for accumulation in regional LNs. SLN800 was injected intradermally in mice, after which the collection and retention of fluorescence in SLNs were measured using indocyanine green (ICG) and its precursor, SLN700, as references. LNs in the cervical, inguinal, jejunal, iliac, and thoracic basins could clearly be distinguished after a low dose intravenous injection of PanLN-Forte. Background fluorescence was significantly lower compared to the parent compound ZW800-3A (p < 0.001). SLN700 and SLN800 specifically targeted SLNs with fluorescence being retained over 40-fold longer than the current clinically used agent ICG. Using SLN700 and SLN800, absolute fluorescence in SLN was at least 10 times higher than ICG in second-tier nodes, even at 1 hour post-injection. Histologically, the fluorescent signal localized in the LN medulla (PanLN-Forte) or sinus entry (SLN700/SLN800). PanLN-Forte and SLN800 appear to be optimal for real-time NIR fluorescence imaging of regional and SLNs, respectively.

Background: Robotic liver surgery represents the most recent evolution in the field of minimally-invasive liver surgery. For planning and guidance of liver resections, surgeons currently rely on preoperative 2-dimensional (2D) CT and/or MR imaging and intraoperative ultrasonography. Translating 2D images into digital 3-dimensional (3D) models may improve both preoperative planning and surgical guidance. The da Vinci® robotic surgical system is a platform suitable for the integration of multiple imaging modalities into one single view. In this study, we describe multimodal imaging options and introduce the Robotic Liver Surgery Cockpit; Methods: in-house developed software was used and validated for segmentation and registration to create a virtual reality 3D model of the liver based on preoperative imaging. The accuracy of the 3D models in the clinical setting was objectively assessed in 15 patients by measuring tumor diameters and subjectively with a postoperative conducted questionnaire; Results: Implementation and applicability of the 3D model in the surgical cockpit was feasible in all patients and the quality of the 3D reconstructions was high in 14 (93%) of cases. Tumor diameters measured on CT and/or MR imaging were comparable to automated measurements using the segmentation software and 3D models; Conclusions: the 3D model was successfully incorporated in the robotic surgery console as part of a multimodality imaging platform and aided the surgeon in planning and guidance of the resection. Future studies should focus on further automation of 3D rendering and progress into augmented reality.

(1) Background: Up to 50% of patients with colorectal cancer either have synchronous colorectal liver metastases (CRLM) or develop CRLM over the course of their disease. Surgery and thermal ablation are the most common local treatment options of choice. Despite development and improvement in local treatment options, (local) recurrence remains a significant clinical problem. Many different imaging modalities can be used in the follow-up after treatment of CRLM, lacking evidence-based international consensus on the modality of choice. In this systematic review, we evaluated 18F-FDG-PET-CT performance after surgical resection, thermal ablation, radioembolization, and neoadjuvant and palliative chemotherapy based on current published literature. (2) Methods: A systematic literature search was performed on the PubMed database. (3) Results: A total of 31 original articles were included in the analysis. Only one suitable study was found describing the role of 18F-FDG-PET-CT after surgery, which makes it hard to draw a firm conclusion. 18F-FDG-PET-CT showed to be of additional value in the follow-up after thermal ablation, palliative chemotherapy, and radioembolization. 18F-FDG-PET-CT was found to be a poor to moderate predictor of pathologic response after neoadjuvant chemotherapy. (4) Conclusions: 18F-FDG-PET-CT is superior to conventional morphological imaging modalities in the early detection of residual disease after thermal ablation and in the treatment evaluation and prediction of prognosis during palliative chemotherapy and after radioembolization, and 18F-FDG-PET-CT could be considered in selected cases after neoadjuvant chemotherapy and surgical resection.

Lung cancer is the most common cancer type worldwide, with non-small cell lung cancer (NSCLC) being the most common subtype. Non-disseminated NSCLC is mainly treated with surgical resection. The intraoperative detection of lung cancer can be challenging, since small and deeply located pulmonary nodules can be invisible under white light. Due to the increasing use of minimally invasive surgical techniques, tactile information is often reduced. Therefore, several intraoperative imaging techniques have been tested to localize pulmonary nodules, of which near-infrared (NIR) fluorescence is an emerging modality. In this systematic review, the available literature on fluorescence imaging of lung cancers is presented, which shows that NIR fluorescence-guided lung surgery has the potential to identify the tumor during surgery, detect additional lesions and prevent tumor-positive resection margins.

Background: We conducted a multicentre phase II trial to investigate feasibility and antitumor activity of sequential FOLFIRINOX and Stereotactic Body Radiotherapy (SBRT) in patients with locally advanced pancreatic cancer (LAPC), (LAPC-1 trial). Methods: Patients with biopsy-proven LAPC treated in four hospitals in the Netherlands between December 2014 and June 2017. Patients received 8 cycles of FOLFIRINOX followed by SBRT (5 fractions/8 Gy) if no tumour progression after the FOLFIRINOX treatment was observed. Primary outcome was 1-year overall survival (OS). Secondary outcomes were median OS, 1-year progression-free survival (PFS), treatment-related toxicity, and resection rate. The study is registered with ClinicalTrials.gov, NCT02292745, and is completed. Findings: Fifty patients were included. Nineteen (38%) patients did not receive all 8 cycles of FOLFIRINOX, due to toxicity (n = 12), disease progression (n = 6), or patients’ preference (n = 1). Thirty-nine (78%) patients received the SBRT treatment. The 1-year OS and PFS were 64% (95% CI: 50%-76%) and 34% (95% CI: 22%-48%), respectively. Thirty grade 3 or 4 adverse events were observed during FOLFIRINOX. Two (5%) grade 3 or 4 adverse events after SBRT were observed. Two (5%) patients died due to a gastro-intestinal bleeding within three months after SBRT were observed. Six (12%) patients underwent a resection, all resulting in a complete (R0) resection. Two patients had a complete pathological response. Interpretation: FOLFIRINOX followed by SBRT in patients with LAPC is feasible and shows relevant antitumor activity. In 6 (12%) patients a potentially curative resection could be pursued following this combined treatment, with a complete histological response being observed in two patients. Keywords: Locally advanced pancreatic cancer, Chemotherapy, Radiotherapy, Surgery, Survival

Sarcomas are a rare heterogeneous group of malignant neoplasms of mesenchymal origin which represent approximately 13% of all cancers in pediatric patients. The most prevalent pediatric bone sarcomas are osteosarcoma (OS) and Ewing sarcoma (ES). Rhabdomyosarcoma (RMS) is the most frequently occurring pediatric soft tissue sarcoma. The median age of OS and ES is approximately 17 years, so this disease is also commonly seen in adults while non-pleiomorphic RMS is rare in the adult population. The mainstay of all treatment regimens is multimodal treatment containing chemotherapy, surgical resection, and sometimes (neo)adjuvant radiotherapy. A clear resection margin improves both local control and overall survival and should be the goal during surgery with a curative intent. Real-time intraoperative fluorescence-guided imaging could facilitate complete resections by visualizing tumor tissue during surgery. This review evaluates whether non-targeted and targeted fluorescence-guided surgery (FGS) could be beneficial for pediatric OS, ES, and RMS patients. Necessities for clinical implementation, current literature, and the positive as well as negative aspects of non-targeted FGS using the NIR dye Indocyanine Green (ICG) were evaluated. In addition, we provide an overview of targets that could potentially be used for FGS in OS, ES, and RMS. Then, due to the time- and cost-efficient translational perspective, we elaborate on the use of antibody-based tracers as well as their disadvantages and alternatives. Finally, we conclude with recommendations for the experiments needed before FGS can be implemented for pediatric OS, ES, and RMS patients.

In assessing the severity of lower extremity arterial disease (LEAD), physicians rely on clinical judgements supported by conventional measurements of macrovascular blood flow. However, current diagnostic techniques provide no information about regional tissue perfusion and are of limited value in patients with chronic limb-threatening ischemia (CLTI). Near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) has been used extensively in perfusion studies and is a possible modality for tissue perfusion measurement in patients with CLTI. In this prospective cohort study, ICG NIR fluorescence imaging was performed in patients with CLTI and control patients using the Quest Spectrum Platform® (Middenmeer, The Netherlands). The time–intensity curves were analyzed using the Quest Research Framework. Fourteen parameters were extracted. Successful ICG NIR fluorescence imaging was performed in 19 patients with CLTI and in 16 control patients. The time to maximum intensity (seconds) was lower for CLTI patients (90.5 vs. 143.3, p = 0.002). For the inflow parameters, the maximum slope, the normalized maximum slope and the ingress rate were all significantly higher in the CLTI group. The inflow parameters observed in patients with CLTI were superior to the control group. Possible explanations for the increased inflow include damage to the regulatory mechanisms of the microcirculation, arterial stiffness, and transcapillary leakage.

Human leukocyte antigen-G (HLA-G) conveys immunological tolerance at the maternal-foetal interface. HLA-G expression by tumour cells may also play such a role, resulting in tumour immune evasion, making HLA-G a potential target for immunotherapies. The aim of this review was to determine to what extent it is justified that HLA-G expression is considered as a target for immune checkpoint inhibiting therapy by critically assessing the association between HLA-G expression by carcinomas and clinical outcome of patients. The used HLA-G-detecting mAb, HLA-G quantification methods and statistically significant HLA-G-associated clinicopathological parameters are discussed. Tumour HLA-G expression correlated with poor clinical outcome in breast, esophageal, gastric and hepatocellular carcinoma patients. Tumour HLA-G expression was not associated with clinical outcome in ovarian and oral carcinoma patients. Cervical, colorectal, lung, and pancreatic carcinoma patients presented discrepant and therefore inconclusive results regarding the association between tumour HLA-G expression and clinical outcome. These disparities might partly be the result of differences in the methodological approach to quantify HLA-G expression between studies. Therefore, implementation of universal methodological procedures is strongly advised. Overall, HLA-G expression did not univocally result in poor clinical outcome of carcinoma patients. This implies that tumour HLA-G expression is not necessarily part of an inhibited tumour-immune response and tumour progression. Consequently, it remains elusive whether HLA-G expression by carcinomas functions as an immune checkpoint molecule affecting a tumour-immune response. It may also reflect derailed control of gene expression in tumours, with no real functional consequences.

(1) Background: Near-infrared fluorescence imaging is a technique capable of assessing tissue perfusion and has been adopted in various fields including plastic surgery, vascular surgery, coronary arterial disease, and gastrointestinal surgery. While the usefulness of this technique has been broadly explored, there is a large variety in the calculation of perfusion parameters. In this systematic review, we aim to provide a detailed overview of current perfusion parameters, and determine the perfusion parameters with the most potential for application in near-infrared fluorescence imaging. (2) Methods: A comprehensive search of the literature was performed in Pubmed, Embase, Medline, and Cochrane Review. We included all clinical studies referencing near-infrared perfusion parameters. (3) Results: A total of 1511 articles were found, of which, 113 were suitable for review, with a final selection of 59 articles. Near-infrared fluorescence imaging parameters are heterogeneous in their correlation to perfusion. Time-related parameters appear superior to absolute intensity parameters in a clinical setting. (4) Conclusions: This literature review demonstrates the variety of parameters selected for the quantification of perfusion in near-infrared fluorescence imaging.

Biomarkers may hold the key towards development and improvement of personalized cancer treatment. For instance, tumour expression of immune system-related proteins may reveal the tumour immune status and, accordingly, determine choice for type of immunotherapy. Therefore, objective evaluation of tumour biomarker expression is needed but often challenging. For instance, human leukocyte antigen (HLA) class I tumour epithelium expression is cumbersome to quantify by eye due to its presence on both tumour epithelial cells and tumour stromal cells, as well as tumour-infiltrating immune cells. In this study, we solved this problem by setting up an immunohistochemical (IHC) double staining using a tissue microarray (TMA) of rectal tumours wherein HLA class I expression was coloured with a blue chromogen, whereas non-epithelial tissue was visualized with a brown chromogen. We subsequently developed a semi-automated image analysis method that identified tumour epithelium as well as the percentage of HLA class I-positive tumour epithelium. Using this technique, we compared HCA2/HC10 and EMR8-5 antibodies for the assessment of HLA class I tumour expression and concluded that EMR8-5 is the superior antibody for this purpose. This IHC double staining can in principle be used for scoring of any biomarker expressed by tumour epithelium.