Publications by authors named "Warner Prevoo"

Purpose: We present a technique that combines Hepatic Arteriography with C-arm CT-Guided Ablation (HepACAGA) to improve tumor visualization, navigation and margin confirmation for percutaneous ablation of liver tumors.

Materials And Methods: All consecutive patients scheduled for HepACAGA between April 20th, 2021, and November 2nd, 2021, were included in this retrospective, cohort study. HepACAGA was performed in an angiography-suite under general anesthesia.

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Background: Combining resection and thermal ablation can improve short-term postoperative outcomes in patients with colorectal liver metastases (CRLM). This study assessed nationwide hospital variation and short-term postoperative outcomes after combined resection and ablation.

Methods: In this population-based study, all CRLM patients who underwent resection in the Netherlands between 2014 and 2018 were included.

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The guidelines for metastatic colorectal cancer crudely state that the best local treatment should be selected from a 'toolbox' of techniques according to patient- and treatment-related factors. We created an interdisciplinary, consensus-based algorithm with specific resectability and ablatability criteria for the treatment of colorectal liver metastases (CRLM). To pursue consensus, members of the multidisciplinary COLLISION and COLDFIRE trial expert panel employed the RAND appropriateness method (RAM).

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Purpose: To assess the difference between renal mass biopsy (RMB) performed either before or during the ablation procedure.

Methods: A retrospective multicenter study was performed in patients with a cT1 renal mass treated with ablation between January 2007 and July 2019, including a search in the national pathology database for patients with a RMB planned for ablation. Patient and tumor characteristics and information on malignant, benign, and non-diagnostic biopsy results were collected to establish rates of overtreatment and number of ablations avoided in case of benign or non-diagnostic histology.

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Approximately, 50% of patients with uveal melanoma develop distant metastasis for which no standard therapy is established. In contrast to cutaneous melanoma, the anti-CTLA-4 antibody ipilimumab showed no clinical activity in uveal melanoma. Liver directed therapies improve local control, but fail to show overall survival (OS) benefit.

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Background: The 10-year overall survival with adjuvant hepatic arterial infusion pump (HAIP) chemotherapy after resection of colorectal liver metastases (CRLMs) was 61% in clinical trials from Memorial Sloan Kettering Cancer Center. A pilot study was performed to evaluate the safety and feasibility of adjuvant HAIP chemotherapy in patients with resectable CRLMs.

Study Design: A phase II study was performed in two centers in The Netherlands.

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There is a clear and unmet clinical need for biomarkers to predict responsiveness to chemotherapy for cancer. We developed an in vitro test based on patient-derived tumor organoids (PDOs) from metastatic lesions to identify nonresponders to standard-of-care chemotherapy in colorectal cancer (CRC). In a prospective clinical study, we show the feasibility of generating and testing PDOs for evaluation of sensitivity to chemotherapy.

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Objective: To investigate the rate of occult SN metastases, oncological outcome, and association of recurrence with the pattern of lymphatic tumour drainage in RCC.

Materials And Methods: A pooled RCC sub-group analysis was conducted of secondary endpoints from a published feasibility and a phase II prospective single-arm SN study to investigate oncological outcome. Patients with cT1-3 (<10 cm) cN0M0 RCC of any sub-type were enrolled.

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Background: Sentinel lymph node biopsy (SLNB) after intratumoral injection of Tc labeled nanocolloid and imaging with scintigraphy and SPECT/CT in renal tumors is feasible. However, sentinel lymph node (SN) non-detection rate with scintigraphy and SPECT/CT is high. The aim of the study was to determine factors affecting non-visualization (NV) of SN imaging in renal tumors.

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Objectives: Cholangiocarcinoma is the second most common primary liver tumour with a poor overall prognosis. Percutaneous hepatic perfusion (PHP) is a directed therapy for primary and secondary liver malignancies, and its efficacy and safety have been shown in different entities. The purpose of this study was to prove the safety and efficacy of PHP in patients with unresectable intrahepatic cholangiocarcinoma (iCCA).

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Purpose: To assess safety and outcome of radiofrequency ablation (RFA) and microwave ablation (MWA) as compared to systemic chemotherapy and partial hepatectomy (PH) in the treatment of colorectal liver metastases (CRLM).

Methods: MEDLINE, Embase and the Cochrane Library were searched. Randomized trials and comparative observational studies with multivariate analysis and/or matching were included.

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Purpose: To evaluate the performance of automated feeder detection (AFD) software (EmboGuide; Philips Healthcare, Best, The Netherlands) on hepatocellular carcinoma (HCC) tumors during transarterial chemoembolization.

Materials And Methods: Forty-four first-time transarterial chemoembolization patients (37 men; mean age, 62 ± 11 years) were enrolled between May 2012 and July 2013. A total of 86 HCC lesions were treated (2.

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Purpose: Lymphatic drainage from renal tumors is unpredictable. In vivo drainage studies of primary lymphatic landing sites may reveal the variability and dynamics of lymphatic connections. The purpose of this study was to investigate the lymphatic drainage pattern of renal tumors in vivo with single photon emission/computerized tomography after intratumor radiotracer injection.

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Background: Molecular intratumour heterogeneity (ITH) is common in clear cell renal carcinomas (ccRCCs). However, it remains unknown whether this is mirrored by heterogeneity of drug responses between metastases in the same patient.

Methods: We performed a retrospective central radiological analysis of patients with treatment-naïve metastatic ccRCC receiving anti-angiogenic tyrosine kinase inhibitors (TKIs) (sunitinib or pazopanib) within three similar phase II trials.

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Background And Objective: Over the last decade, an increasing effort has been put towards the implementation of optical guidance techniques to aid surgeons during cancer surgery. Diffuse reflectance spectroscopy (DRS) and fluorescence spectroscopy (FS) are two of these new techniques. The objective of this study is to investigate whether in vivo optical spectroscopy is able to accurately discriminate colorectal liver metastases (CRLM) from normal liver tissue in vivo.

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There is a strong need to develop clinical instruments that can perform rapid tissue assessment at the tip of smart clinical instruments for a variety of oncological applications. This study presents the first in vivo real-time tissue characterization during 24 liver biopsy procedures using diffuse reflectance (DR) spectroscopy at the tip of a core biopsy needle with integrated optical fibers. DR measurements were performed along each needle path, followed by biopsy of the target lesion using the same needle.

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Objectives: Difficulties in obtaining a representative tissue sample are a major obstacle in timely selecting the optimal treatment for patients with lung cancer or other malignancies. Having a modality to provide needle guidance and confirm the biopsy site selection could be of great clinical benefit, especially when small masses are targeted. The objective of this study was to evaluate whether diffuse reflectance spectroscopy (DRS) at the tip of a core biopsy needle can be used for biopsy site confirmation in real time, thereby enabling optimized biopsy acquisition and improving diagnostic capability.

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Objective: To analyze if prediction of survival for patients with synchronous metastatic renal cell cancer (mRCC) could be further refined by baseline volume of the primary tumor, the metastases, or the remaining volume after surgery; this study was performed because survival expectancies of patients with intermediate-risk mRCC vary substantially.

Material And Methods: The predictive value of the different volumes on overall survival (OS) was analyzed retrospectively in patients with intermediate Memorial Sloan-Kettering Cancer Center (MSKCC) risk profile and ≤3 International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) factors, who received sunitinib in our institute. Tumor volumes were calculated on segmented computed tomography using in-house developed software.

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Purpose: This study presents the first in vivo real-time tissue characterization during image-guided percutaneous lung biopsies using diffuse reflectance spectroscopy (DRS) sensing at the tip of a biopsy needle with integrated optical fibers.

Experimental Design: Tissues from 21 consented patients undergoing lung cancer surgery were measured intraoperatively using the fiber-optic platform capable of assessing various physical tissue properties highly correlated to tissue architecture and composition. In addition, the method was tested for clinical use by performing DRS tissue sensing during 11 routine biopsy procedures in patients with suspected lung cancer.

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[(18)F]Fluorodeoxyglucose (FDG) PET is a functional imaging tool that provides metabolic information, which has the potential to detect a lesion before it becomes anatomically apparent. This ability constitutes a strong argument for using FDG-PET/computed tomography (CT) in the management of oncology patients. Many studies have investigated the accuracy of FDG-PET or FDG-PET/CT for these purposes, but with small sample sizes based on retrospective cohorts.

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Assessment of fatty liver grafts during orthotopic liver transplantation is a challenge due to the lack of real-time analysis options during surgery. Diffuse reflectance spectroscopy (DRS) could be a new diagnostic tool to quickly assess steatosis. Eight hundred and seventy-eight optical measurements were performed in vivo in 17 patients in liver tissue during surgery and ex vivo on liver resection specimens from 41 patients.

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Despite the widespread use of radio frequency (RF) ablation, an effective way to assess thermal tissue damage during and after the procedure is still lacking. We present a method for monitoring RF ablation efficacy based on thermally induced methemoglobin as a marker for full tissue ablation. Diffuse reflectance (DR) spectra were measured from human blood samples during gradual heating of the samples from 37 to 60, 70, and 85°C.

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Background And Aim: Preoperative assessment of the internal mammary artery perforating (IMAP) branches enhances IMAP-based reconstructive procedures. Conventionally, color-flow Doppler, selective catheter arteriography, or CT angiography is used for such assessment. We studied how often these examinations may be rendered superfluous by assessment of previously performed diagnostic examinations.

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Objective: To evaluate the probability of downsizing primary renal tumors by targeted therapy in correlation to size.

Methods: A literature search was conducted and our own data were pooled with data of retrospective series and prospective trials in which patients were treated with tyrosine kinase inhibitors (TKIs) and in which tumor sizes before and after treatment were reported. Included were 89 primary clear cell renal tumors, including 34 from our institutes.

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Background: The level of evidence for efficacy of local treatment of pulmonary metastases is low; therefore, complication rates should be minimized. Minimally invasive techniques may have the potential to reduce morbidity but potentially lead to more local and/or ipsilateral recurrences. The objective of this study was to evaluate the introduction of a new treatment strategy incorporating the increased use of video-assisted thoracic surgery (VATS) and radiofrequency ablation (RFA), weighing complications against recurrence rates.

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