Background: While immune checkpoint inhibition (ICI) has revolutionized the treatment of metastatic cutaneous melanoma, no standard treatments are available for patients with metastatic uveal... Show moreBackground: While immune checkpoint inhibition (ICI) has revolutionized the treatment of metastatic cutaneous melanoma, no standard treatments are available for patients with metastatic uveal melanoma (UM). Several locoregional therapies are effective in the treatment of liver metastases, such as percutaneous hepatic perfusion with melphalan (M-PHP). The available literature suggests that treatment with ICI following locoregional treatment of liver UM metastases can result in clinical response. We hypothesize that combining M-PHP with ICI will lead to enhanced antigen presentation and increased immunomodulatory effect, improving control of both hepatic and extrahepatic disease.Methods: Open-label, single-center, phase Ib/randomized phase II trial, evaluating the safety and efficacy of the combination of M-PHP with ipilimumab (anti-CTLA-4 antibody) and nivolumab (anti-PD-1 antibody) in patients with unresectable hepatic metastases of UM in first-line treatment, with or without the limited extrahepatic disease. The primary objective is to determine the safety, toxicity, and efficacy of the combination regimen, defined by maximum tolerated dose (MTD) and progression-free survival (PFS) at 1 year. Secondary objectives include overall survival (OS) and overall response rate (ORR). A maximum of 88 patients will be treated in phase I and phase II combined. Baseline characteristics will be described with descriptive statistics (t-test, chi-square test). To study the association between risk factors and toxicity, a logistic regression model will be applied. PFS and OS will be summarized using Kaplan-Meier curves.Discussion: This is the first trial to evaluate this treatment combination by establishing the maximum tolerated dose and evaluating the efficacy of the combination treatment. M-PHP has shown to be a safe and effective treatment for UM patients with liver metastases and became the standard treatment option in our center. The combination of ICI with M-PHP is investigated in the currently described trial which might lead to a better treatment response both in and outside the liver. Show less
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... Show morePurposePercutaneous 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. Show less
Simple Summary: Hepatocellular carcinoma (HCC) is one of the deadliest forms of cancer. Selective internal radiation therapy (SIRT) is one of the therapeutic options for treatment of advanced HCC.... Show moreSimple Summary: Hepatocellular carcinoma (HCC) is one of the deadliest forms of cancer. Selective internal radiation therapy (SIRT) is one of the therapeutic options for treatment of advanced HCC. Studies show that SIRT has a high objective response rate, but lack of survival benefit when compared to different treatment modalities. We hypothesized that this is due to potential damage in healthy liver parenchyma as a side-effect of SIRT, resulting in functional changes to the liver. This can ultimately result in liver decompensation and potentially death. The aim of this retrospective study was to assess long-term liver-related complications after SIRT in patients with HCC. We analyzed patients who underwent SIRT and found that liver decompensation occurred more often after SIRT when compared to sorafenib. However, careful patient selection may result in a survival benefit after SIRT when compared to other treatments. The ABLI score may be a valuable prognostic score for selecting patients.Selective internal radiation therapy (SIRT) is used as a treatment for hepatocellular carcinoma (HCC). The aim of this study was to assess long-term liver-related complications of SIRT in patients who had not developed radioembolization-induced liver disease (REILD). The primary outcome was the percentage of patients without REILD that developed Child-Pugh (CP) & GE; B7 liver decompensation after SIRT. The secondary outcomes were overall survival (OS) and tumor response. These data were compared with a matched cohort of patients treated with sorafenib. Eighty-five patients were included, of whom 16 developed REILD. Of the remaining 69 patients, 38 developed liver decompensation CP & GE; B7. The median OS was 18 months. In patients without REILD, the median OS in patients with CP & GE; B7 was significantly shorter compared to those without CP & GE; B7; 16 vs. 31 months. In the case-matched analysis, the median OS was significantly longer in SIRT-treated patients; 16 vs. 8 months in sorafenib. Liver decompensation CP & GE; B7 occurred significantly more in SIRT when compared to sorafenib; 62% vs. 27%. The ALBI score was an independent predictor of liver decompensation (OR 0.07) and OS (HR 2.83). After SIRT, liver decompensation CP & GE; B7 often developed as a late complication in HCC patients and was associated with a shorter OS. The ALBI score was predictive of CP & GE; B7 liver decompensation and the OS, and this may be a valuable marker for patient selection for SIRT. Show less
Background: The combination treatment regimen of thermal ablation (TA) and transarterial chemoembolization (TACE) has gained a place in treatment of hepatocellular carcinoma (HCC) lesions > 3 cm... Show moreBackground: The combination treatment regimen of thermal ablation (TA) and transarterial chemoembolization (TACE) has gained a place in treatment of hepatocellular carcinoma (HCC) lesions > 3 cm unsuitable for surgery. Despite a high heterogeneity in the currently used treatment protocols, the pooled results of combined treatments seem to outperform those of TA or TACE alone. TACE preceding TA has been studied extensively, while results of the reverse treatment sequence are lacking. In this retrospective cohort study we compared the two treatment sequences. Patients and methods: 38 patients (median age: 68.5 yrs (range 40-84), male: 34, liver cirrhosis: 33, early stage HCC: 21, intermediate stage HCC: 17) were included in two tertiary referral centers, of whom 27 were treated with TA and adjuvant TACE (TA + TACE). The other 11 patients received TA with neoadjuvant TACE (TACE + TA). Overall survival (OS), time to progression (TTP) and local tumor progression (LTP) free survival were determined for the entire cohort and compared between the two treatment sequences. Results: The median OS of all patients was 52.7 months and the median time to LTP was 11.5 months (censored for liver transplantation). No differences were found with respect to OS between the two treatment sequences. Median time to LTP for TACE + TA was 23.6 months and 8.1 months for TA + TACE (p = 0.19). Discussion: No statistical differences were found for OS, TTP and time to LTP between patients treated with TA combined with neoadjuvant or adjuvant TACE. Show less
Gorgec, B.; Hansen, I.; Kemmerich, G.; Syversveen, T.; Abu Hilal, M.; Belt, E.J.T.; ... ; CAMINO Study Grp 2021
Background: Abdominal computed tomography (CT) is the standard imaging method for patients with suspected colorectal liver metastases (CRLM) in the diagnostic workup for surgery or thermal ablation... Show moreBackground: Abdominal computed tomography (CT) is the standard imaging method for patients with suspected colorectal liver metastases (CRLM) in the diagnostic workup for surgery or thermal ablation. Diffusion-weighted and gadoxetic-acid-enhanced magnetic resonance imaging (MRI) of the liver is increasingly used to improve the detection rate and characterization of liver lesions. MRI is superior in detection and characterization of CRLM as compared to CT. However, it is unknown how MRI actually impacts patient management. The primary aim of the CAMINO study is to evaluate whether MRI has sufficient clinical added value to be routinely added to CT in the staging of CRLM. The secondary objective is to identify subgroups who benefit the most from additional MRI.Methods: In this international multicentre prospective incremental diagnostic accuracy study, 298 patients with primary or recurrent CRLM scheduled for curative liver resection or thermal ablation based on CT staging will be enrolled from 17 centres across the Netherlands, Belgium, Norway, and Italy. All study participants will undergo CT and diffusion-weighted and gadoxetic-acid enhanced MRI prior to local therapy. The local multidisciplinary team will provide two local therapy plans: first, based on CT-staging and second, based on both CT and MRI. The primary outcome measure is the proportion of clinically significant CRLM (CS-CRLM) detected by MRI not visible on CT. CS-CRLM are defined as liver lesions leading to a change in local therapeutical management. If MRI detects new CRLM in segments which would have been resected in the original operative plan, these are not considered CS-CRLM. It is hypothesized that MRI will lead to the detection of CS-CRLM in >= 10% of patients which is considered the minimal clinically important difference. Furthermore, a prediction model will be developed using multivariable logistic regression modelling to evaluate the predictive value of patient, tumor and procedural variables on finding CS-CRLM on MRI.Discussion: The CAMINO study will clarify the clinical added value of MRI to CT in patients with CRLM scheduled for local therapy. This study will provide the evidence required for the implementation of additional MRI in the routine work-up of patients with primary and recurrent CRLM for local therapy. Show less
Background: There is a paucity of randomized trials demonstrating superior efficacy of drug-coated balloon angioplasty (DCBA) compared with conventional percutaneous transluminal angioplasty (PTA)... Show moreBackground: There is a paucity of randomized trials demonstrating superior efficacy of drug-coated balloon angioplasty (DCBA) compared with conventional percutaneous transluminal angioplasty (PTA) for below-the-knee arterial disease in patients with critical limb ischemia.Purpose: To compare DCBA versus PTA for below-the-knee lesions in participants with critical limb ischemia through 12 months.Materials and Methods: In this prospective, randomized, two-center, double-blind superiority study, participants with critical limb ischemia with rest pain or tissue loss with atherosclerotic disease in the native below-the-knee arteries were randomly assigned (in a one-to-one ratio) to DCBA or PTA after stratification for diabetes and renal failure between November 2013 and October 2017. The primary efficacy end point was angiographic primary patency at 6 months analyzed on an intention-to-treat basis. Secondary end points through 12 months were composed of major adverse events including death and major amputations, wound healing, limb salvage, clinically driven target-lesion revascularization, and amputation-free survival. Primary and binary secondary end points, analyzed by using generalized-linear model and time-to-event analyses, were estimated with Kaplan-Meier survival curves and hazard ratios (Cox regression).Results: Seventy participants (mean age, 61 years 6 10 [standard deviation]; 43 men) in the DCBA group and 68 (mean age, 64 years 6 10; 50 men) in the PTA group were evaluated. The percentage of patients with angiographic primary patency at 6 months was 43% (30 of 70) in the DCBA group and 38% (26 of 68) in the PTA group (P=.48). Through 12 months, the percentage of deaths was similar: 21% in the DCBA group and 16% in the PTA group (P=.43). Amputation-free survival rate assessed with Kaplan-Meier curves differed through 12 months: 59% (41 of 70) in the DCBA group compared with 78% (53 of 68) in the PTA group (P=.01).Conclusion: In participants with critical limb ischemia, the drug-coated balloon angioplasty group and the conventional percutaneous transluminal angioplasty group had similar primary patency rates at 6 months after treatment of below-the-knee arteries. Amputation-free survival rates through 12 months were higher in the percutaneous transluminal angioplasty group. (C) RSNA, 2021 Show less
Background Hepatocellular carcinoma (HCC) recurrence rates following locoregional treatment are high. As multireceptor tyrosine kinase inhibitors targeting vascular endothelial growth factor... Show moreBackground Hepatocellular carcinoma (HCC) recurrence rates following locoregional treatment are high. As multireceptor tyrosine kinase inhibitors targeting vascular endothelial growth factor receptors (VEGFRs) are effective in advanced HCC, we assessed the efficacy and safety of neoadjuvant systemic treatment with dovitinib in early- and intermediate-stage HCC. Materials and Methods Twenty-four patients with modified Child-Pugh class A early- and intermediate-stage HCC received neoadjuvant oral dovitinib 500 mg daily (5 days on/2 days off) for 4 weeks, followed by locoregional therapy. Primary endpoints were objective response rates and intratumoral blood flow changes. Secondary endpoints were safety, pharmacodynamical plasma markers of VEGFR-blockade, time to progression (TTP), and overall survival (OS). Results Modified RECIST overall response rate was 48%, including 13% complete remission, and despite dose reduction/interruption in 83% of patients, intratumoral perfusion index decreased significantly. Grade 3-4 adverse events, most frequently (on-target) hypertension (54%), fatigue (25%), and thrombocytopenia (21%), occurred in 88% of patients. Plasma VEGF-A, VEGF-D, and placental growth factor increased significantly, whereas sTie-2 decreased, consistent with VEGFR-blockade. Following neoadjuvant dovitinib, all patients could proceed to their original planned locoregional treatment. No delayed toxicity occurred. Seven patients (three early, four intermediate stage) underwent orthotopic liver transplant after median 11.4 months. Censoring at transplantation, median TTP and OS were 16.8 and 34.8 months respectively; median cancer-specific survival was not reached. Conclusion Already after a short 4-week dovitinib treatment period, intratumoral blood flow reduction and modest antitumor responses were observed. Although these results support use of systemic neoadjuvant strategies, the poor tolerability indicates that dovitinib dose adaptations are required in HCC. Implications for Practice Orthotopic liver transplantation may cure early and intermediate-stage hepatocellular carcinoma. Considering the expected waiting time >6 months because of donor liver scarcity, there is an unmet need for effective neoadjuvant downsizing strategies. Angiogenesis inhibition by dovitinib does not negatively affect subsequent invasive procedures, is safe to administer immediately before locoregional therapy, and may provide a novel treatment approach to improve patient outcomes if tolerability in patients with hepatocellular carcinoma can be improved by therapeutic drug monitoring and personalized dosing. Show less
Elfrink, A.K.E.; Nieuwenhuizen, S.; Tol, M.P. van den; Burgmans, M.C.; Prevoo, W.; Coolsen, M.M.E.; ... ; Dutch Hepato Bili 2021
Background: Combining resection and thermal ablation can improve short-term postoperative outcomes in patients with colorectal liver metastases (CRLM). This study assessed nationwide hospital... Show moreBackground: 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. After propensity score matching for age, ASA-score, Charlson-score, diameter of largest CRLM, number of CRLM and earlier resection, postoperative outcomes were compared. Postoperative complicated course (PCC) was defined as discharge after 14 days or a major complication or death within 30 days of surgery.Results: Of 4639 included patients, 3697 (80%) underwent resection and 942 (20%) resection and ablation. Unadjusted percentage of patients who underwent resection and ablation per hospital ranged between 4 and 44%. Hospital variation persisted after case-mix correction. After matching, 734 patients remained in each group. Hospital stay (median 6 vs. 7 days, p = 0.011), PCC (11% vs. 14.7%, p = 0.043) and 30-day mortality (0.7% vs. 2.3%, p = 0.018) were lower in the resection and ablation group. Differences faded in multivariable logistic regression due to inclusion of major hepatectomy.Conclusion: Significant hospital variation was observed in the Netherlands. Short-term postoperative outcomes were better after combined resection and ablation, attributed to avoiding complications associated with major hepatectomy. Show less
Purpose To investigate the performance of two microwave ablation (MWA) systems regarding ablation volume, ablation shape and variability. Materials and Methods In this ex vivo study, the Emprint... Show morePurpose To investigate the performance of two microwave ablation (MWA) systems regarding ablation volume, ablation shape and variability. Materials and Methods In this ex vivo study, the Emprint and Amica MWA systems were used to ablate porcine livers at 4 different settings of time and power (3 and 5 minutes at 60 and 80 Watt). In total, 48 ablations were analysed for ablation size and shape using Vitrea Advanced Visualization software after acquisition of a 7T MRI scan. Results Emprint ablations were smaller (11,1 vs. 21,1 mL p < 0.001), more spherical (sphericity index of 0.89 vs. 0.59 p < 0.001) and showed less variability than Amica ablations. In both systems, longer ablation time and higher power resulted in significantly larger ablation volumes. Conclusion Emprint ablations were more spherical, and the results showed a lower variability than those of Amica ablations. This comes at the price of smaller ablation volumes. Show less
Meershoek, P.; Berg, N.S. van den; Lutjeboer, J.; Burgmans, M.C.; Meer, R.W. van der; Rijswijk, C.S.P. van; ... ; Leeuwen, F.W.B. van 2021
Purpose: The goal of our study was to determine the influence of ultrasound (US)-coupled volume navigation on the use of computed tomography (CT) during minimally-invasive radiofrequency and... Show morePurpose: The goal of our study was to determine the influence of ultrasound (US)-coupled volume navigation on the use of computed tomography (CT) during minimally-invasive radiofrequency and microwave ablation procedures of liver lesions.Method: Twenty-five patients with 40 liver lesions of different histological origin were retrospectively analysed. Lesions were ablated following standard protocol, using 1) conventional US-guidance, 2) manual registered volume navigation (mVNav), 3) automatic registered (alpha VNav) or 4) CT-guidance. In case of ultrasonographically inconspicuous lesions, conventional US-guidance was abandoned and mVNav was used. If mVNav was also unsuccessful, the procedure was either continued with alpha VNav or CT-guidance. The number, size and location of the lesions targeted using the different approaches were documented.Results: Of the 40 lesions, sixteen (40.0 %) could be targeted with conventional US-guidance only, sixteen (40.0 %) with mVNav, three (7.5 %) with aVNav and five (12.5 %) only through the use of CT-guidance. Of the three alternatives (mVNav, alpha VNav and CT only) the mean size of the lesions targeted using mVNav (9.1 +/- 4.6 mm) was significantly smaller from those targeted using US-guidance only (20.4 +/- 9.4 mm; p < 0.001). The location of the lesions did not influence the selection of the modality used to guide the ablation.Conclusions: In our cohort, mVNav allowed the ablation procedure to become less dependent on the use of CT. mVNav supported the ablation of lesions smaller than those that could be ablated with US only and doubled the application of minimally-invasive US-guided ablations. Show less
Objective: Evaluation of the trends in incidence, diagnostics, treatment and survival of patients with hepatocellular carcinoma (HCC) in the Netherlands.Method: Data regarding incidence,... Show moreObjective: Evaluation of the trends in incidence, diagnostics, treatment and survival of patients with hepatocellular carcinoma (HCC) in the Netherlands.Method: Data regarding incidence, diagnostics, primary treatment and survival of patients with HCC in the period 2009-2016 were obtained from the Netherlands Cancer Registry. Trends in incidence, diagnostics, various treatment modalities (except liver transplantation, due to inaccurate data) and regional treatment preferences were analysed. Survival was evaluated using Kaplan-Meier curves and multivariable Cox proportional hazard regression modelling.Results: In the period of 2009-2016, 3838 patients were diagnosed with HCC. A distinct decrease in the percentage of patients who underwent tumour biopsy was observed (from 51% in 2009-2010 to 42% in 2015-2016). Percentage of patients who underwent cancer treatment increased markedly (from 49% in 2009-2010 to 57% in 2015-2016), mainly because of an increasing use of resection and ablation. The number of hospitals where resections were performed or sorafenib treatment prescribed decreased slightly. The number of hospitals sporadically (<1 ablation per year) performing ablations increased. There were significant differences between regions in the application of resection, ablation and transarterial chemoembolisation /radioembolisation (p < 0.05 after 'case mix'-correction). One-, 3 and 5-year survival of patients with HCC significantly improved in the studied period. Receiving cancer treatment was associated with increased survival, whereas increasing age and an advanced tumour stage were both associated with decreased survival.Conclusion: From 2009 to 2016, patients with hepatocellular carcinoma more often received cancer treatment and their survival improved. There were significant differences in types of treatment between various regions. (C) 2020 Elsevier Ltd. All rights reserved. Show less
Background Ocular melanoma is the most common primary intraocular malignancy and has a very poor prognosis once liver metastases occur. The aim of this study was to prospectively assess the... Show moreBackground Ocular melanoma is the most common primary intraocular malignancy and has a very poor prognosis once liver metastases occur. The aim of this study was to prospectively assess the efficacy and safety of percutaneous hepatic perfusion with melphalan (M-PHP) using the new second-generation (GEN 2) hemofiltration system in patients with ocular melanoma metastases confined to the liver. Methods Prospective, single-center, single-arm, phase II study including patients with unresectable ocular melanoma metastases confined to the liver. Treatment consisted of two M-PHP procedures at 6-8 weeks interval. Procedures were performed using the CHEMOSAT (GEN 2) system with 3 mg/kg melphalan. Primary endpoints were overall response rate (ORR) and best overall response (BOR). Secondary endpoints included overall survival (OS), progression-free survival (PFS), hepatic PFS (hPFS), and safety. Results Sixty-four M-PHP procedures were performed in 35 patients between February 2014 and June 2017. The ORR was 72%. BOR was as follows: complete response in 3%, partial response in 69%, stable disease in 13%, and progressive disease in 16%. There was no treatment-related mortality. Fourteen serious adverse events occurred. At a median follow-up of 19.1 months (range 5.6-69.5), median OS was 19.1 months and was significantly longer in responders than in nonresponders (27.5 vs. 11.9 months, p < 0.001). The 1- and 2-year OS was 77% and 43%, respectively. PFS and hPFS were 7.6 and 11.2 months, respectively. Conclusions M-PHP using the GEN 2 filter can achieve a high ORR and prolonged survival in patients with liver-only ocular melanoma metastases. Show less
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... Show moreThe 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). Statements regarding patient, disease, tumor and treatment characteristics were categorized as appropriate, equipoise or inappropriate. Patients with ECOG <= 2, ASA <= 3 and Charlson comorbidity index <= 8 should be considered fit for curative-intent local therapy. When easily resectable and/or ablatable (stage IVa), (neo)adjuvant systemic therapy is not indicated. When requiring major hepatectomy (stage IVb), neo-adjuvant systemic therapy is appropriate for early metachronous disease and to reduce procedural risk. To downstage patients (stage IVc), downsizing induction systemic therapy and/or future remnant augmentation is advised. Disease can only be deemed permanently unsuitable for local therapy if downstaging failed (stage IVd). Liver resection remains the gold standard. Thermal ablation is reserved for unresectable CRLM, deep-seated resectable CRLM and can be considered when patients are in poor health. Irreversible electroporation and stereotactic body radiotherapy can be considered for unresectable perihilar and perivascular CRLM 0-5cm. This consensus document provides per-patient and per-tumor resectability and ablatability criteria for the treatment of CRLM. These criteria are intended to aid tumor board discussions, improve consistency when designing prospective trials and advance intersociety communications. Areas where consensus is lacking warrant future comparative studies. Show less
Background In patients with colorectal liver metastases (CRLM) preoperative imaging may include contrast-enhanced (ce) MRI and [F-18]fluorodeoxyglucose (F-18-FDG) PET-CT. This study assessed trends... Show moreBackground In patients with colorectal liver metastases (CRLM) preoperative imaging may include contrast-enhanced (ce) MRI and [F-18]fluorodeoxyglucose (F-18-FDG) PET-CT. This study assessed trends and variation between hospitals and oncological networks in the use of preoperative imaging in the Netherlands.Methods Data for all patients who underwent liver resection for CRLM in the Netherlands between 2014 and 2018 were retrieved from a nationwide auditing database. Multivariable logistic regression analysis was used to assess use of ceMRI, F-18-FDG PET-CT and combined ceMRI and F-18-FDG PET-CT, and trends in preoperative imaging and hospital and oncological network variation.Results A total of 4510 patients were included, of whom 1562 had ceMRI, 872 had F-18-FDG PET-CT, and 1293 had combined ceMRI and F-18-FDG PET-CT. Use of ceMRI increased over time (from 9.6 to 26.2 per cent; P < 0.001), use of F-18-FDG PET-CT decreased (from 28.6 to 6.0 per cent; P < 0.001), and use of both ceMRI and F-18-FDG PET-CT 16.9 per cent) remained stable. Unadjusted variation in the use of ceMRI, F-18-FDG PET-CT, and combined ceMRI and F-18-FDG PET-CT ranged from 5.6 to 100 per cent between hospitals. After case-mix correction, hospital and oncological network variation was found for all imaging modalities.Discussion Significant variation exists concerning the use of preoperative imaging for CRLM between hospitals and oncological networks in the Netherlands. The use of MRI is increasing, whereas that of F-18-FDG PET-CT is decreasing. Show less