Gunnar Gaffke

Local Response and Impact on Survival After Local Ablation of Liver Metastases From Colorectal Carcinoma by Computed Tomography–Guided High-Dose-Rate Brachytherapy

PURPOSEnTo determine local tumor control after CT-guided brachytherapy at various dose levels and the prognostic impact of extensive cytoreduction in colorectal liver metastases.nnnMETHODS AND MATERIALSnSeventy-three patients were treated on a single-center prospective trial that was initially designed to be randomized to three dose levels of 15 Gy, 20 Gy, or 25 Gy per lesion, delivered in a single fraction. However, because there was a high rate of cross-over of subjects from higher to lower dose levels, this study is better understood as a prospective trial with three dose levels. No upper size limit for the metastases was applied. We assessed time to local progression, progression-free survival, and overall survival.nnnRESULTSnAccording to safety constraints cross-over was performed. The final assignment was n = 98, n = 68, and nxa0=xa033 in the 15-Gy, 20-Gy, and 25-Gy groups, respectively. Median diameter of the largest tumor lesion in each patient was 5 cm (range, 1-13.5 cm). Estimated mean local recurrence-free survival for all lesions was 34 months (median not reached). The group assigned to 15 Gy after cross-over displayed 34 local recurrences out of 98 lesions; 20 Gy, 15 out of 68 lesions; 25 Gy, 1 out of 33 lesions. The difference between the 25-Gy and the 20-Gy or 15-Gy group was significant (p < 0.05). Repeated local tumor ablations were the most prominent factor for increased survival and dominated additional systemic antitumor treatments.nnnCONCLUSIONSnLocal tumor control after CT-guided brachytherapy of colorectal liver metastases demonstrated a strong dose dependency. The role of extensive minimally invasive tumor ablation in metastatic colorectal cancer needs to be further established.

Embolization of the Gastroduodenal Artery Before Selective Internal Radiotherapy: A Prospectively Randomized Trial Comparing Platinum-Fibered Microcoils with the Amplatzer Vascular Plug II

The Amplatzer Vascular Plug II (AVPxa0II) is a novel device for transcatheter vessel occlusion, for which only limited comparative data exist. Embolotherapy of the gastroduodenal artery (GDA) is essential before internal radiotherapy (SIRT) in order to prevent radiation-induced peptic ulcerations due to migration of yttrium-90 microspheres. The purpose of this study was to compare the vascular anatomical limitations, procedure time, effectiveness, and safety of embolization of the GDA with coils versus the AVPxa0II. Fifty patients stratified for SIRT were prospectively randomized for embolization of the GDA with either coils or the AVPxa0II. The angle between the aorta and the celiac trunk, diameter of the GDA, fluoroscopy time and total time for embolization, number of embolization devices, complications, and durability of vessel occlusion at follow-up angiography for SIRT were recorded. A t-test was used for statistical analysis. Embolizations with either coils or the AVPxa0II were technically feasible in all but two patients scheduled for embolization of the GDA with the AVPxa0II. In both cases the plug could not be positioned due to the small celiac trunk outlet angles of 17° and 21°. The mean diameter of the GDA was 3.7xa0mm (range, 2.2–4.8xa0mm) for both groups. The procedures differed significantly in fluoroscopy time (7.8xa0min for coils vs. 2.6xa0min for the AVPxa0II; Pxa0<xa00.001) and embolization time (23.1xa0min for coils vs. 8.8xa0min for the AVPxa0II; Pxa0<xa00.001). A mean of 6.0xa0±xa03.2 coils were used for GDA embolization, while no more than one AVPxa0II was needed for successful vessel occlusion (Pxa0<xa00.001). One coil migration occurred during coil embolization, whereas no procedural complication was encountered with the use of the AVPxa0II. Vessel reperfusion was noted in only one patient, in whom coil embolization was performed. In conclusion, embolization of the GDA with the AVPxa0II is safe, easy, rapid, and highly effective; only an extremely sharp-angled celiac trunk outlet represented an anatomical limitation for device deployment.

Laser-induced thermotherapy (LITT) of liver metastases: MR-guided percutaneous insertion of an MRI-compatible irrigated microcatheter system using a closed high-field unit.

To evaluate the efficacy and safety of a new MRI‐compatible irrigated laser microcatheter system for thermal ablation of liver metastases.

Magnetic resonance-guided freehand radiofrequency ablation of malignant liver lesions: a new simplified and time-efficient approach using an interactive open magnetic resonance scan platform and hepatocyte-specific contrast agent.

ObjectivesThe aims of this study were to develop magnetic resonance (MR)–guided freehand radiofrequency ablation (RFA) using a near-real-time interactive MR platform in an open 1.0-T MR scanner and to determine the feasibility and safety of this new approach in the clinical setting. MethodsThe study was performed using an open 1.0-T MR system and a low-pass filter to prevent interaction between the RFA generator and the scanner. Artifact size of the radiofrequency needle was measured in 2 perpendicular views (transversal [tra] and coronal [cor]) in vitro and in the tra orientation in vivo for diagnostic (T1 high resolution isotropic volume excitation [THRIVE]/T2 turbo spin-echo [TSE]) and near-real-time (T1 fast-field-echo [FFE]) imaging. A liver-specific contrast medium (gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid) was administered 20 minutes before the intervention to enhance lesion visibility. Visibility was rated and compared for both interventional and diagnostic imaging sequences using a 10-point grading scale. Intervention time and complications were recorded. ResultsThe mean diameter of needle artifact size for interventional T1 FFE was 17.4 ± 0.7 mm (tra) and 17.1 ± 1.1 mm (cor) in vitro and 15.2 ± 1.5 mm (tra) in vivo. Artifact size for diagnostic imaging was 12.5 ± 1.8 mm (tra) and 11.2 ± 1.4 mm (cor) in vitro and 10.5 ± 1.7 mm in vivo using THRIVE and 8.1 ± 2.4 mm (tra) and 10.8 ± 1.8 mm (cor) in vitro and 9.7 ± 2.0 mm (tra) in vivo using T2 TSE.A total of 57 patients with liver malignancies (mean tumor size, 17 ± 7 mm) underwent freehand MR-guided RFA. In all patients, the ablative procedure was technically successful. Lesion visibility of the diagnostic T2 TSE sequence (4 ± 2) was significantly decreased compared with both the diagnostic (THRIVE, 7 ± 2) and interventional (T1 FFE, 8 ± 1) T1-weighted sequences. Mean time to position the applicator was 7.5 ± 2 minutes. Procedure times ranged from 30 to 60 minutes. The mean in-room time was 57 ± 22 minutes. No major complications were recorded. ConclusionsMagnetic resonance–guided freehand RFA using a near-real-time interactive MR platform in an open 1.0-T MR scanner is feasible, safe, and applicable in clinical routine. The administration of a hepatocyte-specific contrast agent enhances lesion visualization and therefore improves targeting. Without the need for additional sophisticated devices, this new approach simplifies and shortens the RFA procedure compared with previously published methods.

Local arterial infusion of superparamagnetic iron oxide particles in hepatocellular carcinoma: A feasibility and 3.0 T MRI study.

Objectives:We sought to prove feasibility of selective arterial infusion of superparamagnetic iron oxide (SPIO) particles in patients with hepatocellular carcinoma (HCC). Materials and Methods:We studied 13 patients with HCC who underwent modified transarterial chemoembolization (TACE). Six patients received concurrent infusion of Ferucarbotran (Resovist, Schering, Berlin, Germany) in tumor-feeding arteries, and another 6 received MFL AS (MagForce, Nanotechnologies, Berlin, Germany). The iron content of both dispersions was 3.92 mg. One patient served as a control. All patients underwent magnetic resonance imaging (MRI) as baseline and immediate follow-up investigation. Results:Selective arterial infusion of both SPIO particles resulted in significant intratumoral signal intensity decrease on T1-weighted sequences (P < 0.0001), which was greater after MagForce infusion compared with Resovist (P = 0.002). Only minimal amounts of dispersed particles were found in adjacent normal liver parenchyma. No change in intratumoral signal intensity was noted when ferromagnetic particles were omitted. Conclusions:Modified TACE with selective arterial infusion of SPIO particles can be used for precise tumor targeting in patients with HCC, for which MagForce appeared superior to Resovist.

[Current status of MRI diagnostics with liver-specific contrast agents. Gd-EOB-DTPA and Gd-BOPTA].

ZusammenfassungDie Kontrastmittel Gd-EOB-DTPA und Gd-BOPTA können per Bolusinjektion administriert werden und sind geeignet, sowohl als Vaskularisationsmarker als auch Marker der hepatobiliären Exkretion in der MRT verwendet zu werden. In dieser Übersichtsarbeit werden spezifische Eigenschaften der Kontrastmittel und der Stand der klinischen Entwicklung dargestellt. Im Vergleich zur CT und zur MRT mit unspezifischen extrazellulären Gd-Chelaten ergeben sich Vorteile der leberspezifischen Kontrastmittel für die Differenzierung unklarer Leberläsionen, für die Anhebung der Detektionsrate sowie die Untersuchung des Gallengangsystems.AbstractThe contrast agents Gd-EOB-DTPA and Gd-BOPTA can be administered by bolus injection and are appropriate for use in MRI both as vascularization markers and markers of hepatobiliary excretion. This contribution presents an overview of the specific characteristics of contrast media and the status of clinical development. In comparison to CT and to MRI with unspecific extracellular Gd-chelates, liver-specific contrast agents offer advantages in differentiating unclear liver lesions, increasing the detection rate, and examining the bile duct system.

Current concepts and recent developments of laser ablation in tumor therapy

ZusammenfassungFragestellungIn diesem Artikel werden methodische Innovationen und klinische Ergebnisse der perkutanen interventionellen Laserablation von Tumoren mit neueren Techniken vorgestellt.MethodikIm interdisziplinären Konsens wurden 182xa0Patienten (Lebertumoren: 131, andere Tumoren—Knochen, Lunge, weitere Tumoren: 51) mit 1–6 Applikatoren behandelt. Die Interventionen erfolgten in Kombination verschiedener Modalitäten (CT/MRT; CT/US) oder ausschließlich im geschlossenen MRT (1,5xa0T) mit direkt postinterventioneller MRT-Kontrolle.ErgebnisseBei Lebertumoren wurde eine Ablationsrate von insgesamt 90,9% erzielt, die MRT erwies sich als optimale Methode zur Prozesssteuerung und direkten postinterventionellen Kontrolle. Die Komplikationsrate („major events“) betrug 5,4%. Bei nichthepatischen Tumoren ergab sich eine hohe technische Erfolgsrate mit organabhängig unterschiedlichem klinischem Erfolg.SchlussfolgerungenDie Laserablation mit neuen Techniken ist ein sicheres und nebenwirkungsarmes Verfahren zur Behandlung von Leber- und anderen Tumoren bis zu einer Größe von 5xa0cm. Die MRT hat sich für die exakte multiplanare Abbildung des Tumors, die Prozesssteuerung und die Erfolgskontrolle der Laserablation bewährt.AbstractPurposeThe purpose of this paper is to present technical innovations and clinical results of percutaneous interventional laser ablation of tumors using new techniques.MethodsLaser ablation was performed in 182xa0patients (liver tumors: 131, non hepatic tumors—bone, lung, others: 51) after interdisciplinary consensus was obtained. The procedure was done using a combination of imaging modalities (CT/MRI, CT/US) or only closed high field MRI (1.5xa0T). All patients received an MRI-scan immediately after laser ablation.ResultsIn 90.9% of the patients with liver tumors, a complete ablation was achieved. Major events occurred in 5.4%. The technical success rate of laser ablation in non-hepatic tumors was high, clinical results differed depending on the treated organ.ConclusionsThe treatment of tumors of the liver and other organs up to 5xa0cm by laser ablation was a safe procedure with a low rate of complications and side effects. Image guidance by MRI is advantageous for precise tumor visualization in all dimensions, therapy monitoring, and control of laser ablation results.

Aktueller Stand und Entwicklungen der Laserablation in der Tumortherapie

ZusammenfassungFragestellungIn diesem Artikel werden methodische Innovationen und klinische Ergebnisse der perkutanen interventionellen Laserablation von Tumoren mit neueren Techniken vorgestellt.MethodikIm interdisziplinären Konsens wurden 182xa0Patienten (Lebertumoren: 131, andere Tumoren—Knochen, Lunge, weitere Tumoren: 51) mit 1–6 Applikatoren behandelt. Die Interventionen erfolgten in Kombination verschiedener Modalitäten (CT/MRT; CT/US) oder ausschließlich im geschlossenen MRT (1,5xa0T) mit direkt postinterventioneller MRT-Kontrolle.ErgebnisseBei Lebertumoren wurde eine Ablationsrate von insgesamt 90,9% erzielt, die MRT erwies sich als optimale Methode zur Prozesssteuerung und direkten postinterventionellen Kontrolle. Die Komplikationsrate („major events“) betrug 5,4%. Bei nichthepatischen Tumoren ergab sich eine hohe technische Erfolgsrate mit organabhängig unterschiedlichem klinischem Erfolg.SchlussfolgerungenDie Laserablation mit neuen Techniken ist ein sicheres und nebenwirkungsarmes Verfahren zur Behandlung von Leber- und anderen Tumoren bis zu einer Größe von 5xa0cm. Die MRT hat sich für die exakte multiplanare Abbildung des Tumors, die Prozesssteuerung und die Erfolgskontrolle der Laserablation bewährt.AbstractPurposeThe purpose of this paper is to present technical innovations and clinical results of percutaneous interventional laser ablation of tumors using new techniques.MethodsLaser ablation was performed in 182xa0patients (liver tumors: 131, non hepatic tumors—bone, lung, others: 51) after interdisciplinary consensus was obtained. The procedure was done using a combination of imaging modalities (CT/MRI, CT/US) or only closed high field MRI (1.5xa0T). All patients received an MRI-scan immediately after laser ablation.ResultsIn 90.9% of the patients with liver tumors, a complete ablation was achieved. Major events occurred in 5.4%. The technical success rate of laser ablation in non-hepatic tumors was high, clinical results differed depending on the treated organ.ConclusionsThe treatment of tumors of the liver and other organs up to 5xa0cm by laser ablation was a safe procedure with a low rate of complications and side effects. Image guidance by MRI is advantageous for precise tumor visualization in all dimensions, therapy monitoring, and control of laser ablation results.

Aktueller Stand und Entwicklungen der Laserablation in der Tumortherapie@@@Laser ablation of tumors: current concepts and recent developments

ZusammenfassungFragestellungIn diesem Artikel werden methodische Innovationen und klinische Ergebnisse der perkutanen interventionellen Laserablation von Tumoren mit neueren Techniken vorgestellt.MethodikIm interdisziplinären Konsens wurden 182xa0Patienten (Lebertumoren: 131, andere Tumoren—Knochen, Lunge, weitere Tumoren: 51) mit 1–6 Applikatoren behandelt. Die Interventionen erfolgten in Kombination verschiedener Modalitäten (CT/MRT; CT/US) oder ausschließlich im geschlossenen MRT (1,5xa0T) mit direkt postinterventioneller MRT-Kontrolle.ErgebnisseBei Lebertumoren wurde eine Ablationsrate von insgesamt 90,9% erzielt, die MRT erwies sich als optimale Methode zur Prozesssteuerung und direkten postinterventionellen Kontrolle. Die Komplikationsrate („major events“) betrug 5,4%. Bei nichthepatischen Tumoren ergab sich eine hohe technische Erfolgsrate mit organabhängig unterschiedlichem klinischem Erfolg.SchlussfolgerungenDie Laserablation mit neuen Techniken ist ein sicheres und nebenwirkungsarmes Verfahren zur Behandlung von Leber- und anderen Tumoren bis zu einer Größe von 5xa0cm. Die MRT hat sich für die exakte multiplanare Abbildung des Tumors, die Prozesssteuerung und die Erfolgskontrolle der Laserablation bewährt.AbstractPurposeThe purpose of this paper is to present technical innovations and clinical results of percutaneous interventional laser ablation of tumors using new techniques.MethodsLaser ablation was performed in 182xa0patients (liver tumors: 131, non hepatic tumors—bone, lung, others: 51) after interdisciplinary consensus was obtained. The procedure was done using a combination of imaging modalities (CT/MRI, CT/US) or only closed high field MRI (1.5xa0T). All patients received an MRI-scan immediately after laser ablation.ResultsIn 90.9% of the patients with liver tumors, a complete ablation was achieved. Major events occurred in 5.4%. The technical success rate of laser ablation in non-hepatic tumors was high, clinical results differed depending on the treated organ.ConclusionsThe treatment of tumors of the liver and other organs up to 5xa0cm by laser ablation was a safe procedure with a low rate of complications and side effects. Image guidance by MRI is advantageous for precise tumor visualization in all dimensions, therapy monitoring, and control of laser ablation results.

Aktueller Stand der MRT-Diagnostik mit leberspezifischen Kontrastmitteln@@@Current status of MRI diagnostics with liver-specific contrast agents: Gd-EOB-DTPA und Gd-BOPTA@@@Gd-EOB-DTPA and Gd-BOPTA

ZusammenfassungDie Kontrastmittel Gd-EOB-DTPA und Gd-BOPTA können per Bolusinjektion administriert werden und sind geeignet, sowohl als Vaskularisationsmarker als auch Marker der hepatobiliären Exkretion in der MRT verwendet zu werden. In dieser Übersichtsarbeit werden spezifische Eigenschaften der Kontrastmittel und der Stand der klinischen Entwicklung dargestellt. Im Vergleich zur CT und zur MRT mit unspezifischen extrazellulären Gd-Chelaten ergeben sich Vorteile der leberspezifischen Kontrastmittel für die Differenzierung unklarer Leberläsionen, für die Anhebung der Detektionsrate sowie die Untersuchung des Gallengangsystems.AbstractThe contrast agents Gd-EOB-DTPA and Gd-BOPTA can be administered by bolus injection and are appropriate for use in MRI both as vascularization markers and markers of hepatobiliary excretion. This contribution presents an overview of the specific characteristics of contrast media and the status of clinical development. In comparison to CT and to MRI with unspecific extracellular Gd-chelates, liver-specific contrast agents offer advantages in differentiating unclear liver lesions, increasing the detection rate, and examining the bile duct system.