Current use of percutaneous image-guided tumor ablation for the therapy of liver tumors: lessons learned from the registry of the German Society for Interventional Radiology and Minimally Invasive Therapy (DeGIR) 2018-2022

Safety and Effectiveness of Microwave Ablation of Liver Tumors: Initial Real-World Results from the Multinational NeuWave Observational Liver Ablation (NOLA) Registry

PURPOSE

To investigate the safety and effectiveness of microwave ablation (MWA) for treating liver tumors using real-world data from a multicenter registry (NeuWave Observational Liver Ablation [NOLA]).

MATERIALS AND METHODS

NOLA is approved to enroll up to 1,500 adults treated with MWA and follow them for 5 years. Initial data for 615 patients treated across 24 tertiary healthcare centers in the United States (14), Europe (8), and Asia (2), from January 2020 to October 2022, are summarized herein. Effectiveness and safety endpoints included technical success (TS), technique efficacy (TE), local tumor progression (LTP), adverse events (AEs), and overall survival (OS). AEs were retrospectively graded according to the Society of Interventional Radiology (SIR) classification. A total of 615 patients (male, 72.7%; median age, 66 years; range, 25-89 years) underwent 721 MWA sessions to treat 760 liver tumors, with 95.6% of sessions performed percutaneously.

RESULTS

TS and TE were achieved in 98.1% (730/744) and 95.1% (615/647) of tumors, respectively. The cumulative incidence of LTP at 12 months was 11.9% (95% confidence interval [CI], 8.8%-15.5%) for patients. Within 30 days following the ablation, 408 AEs were reported, with 78.4% (320/408) classified as mild, 3.9% (16/408) as moderate, and 16.9% (69/408) as severe AEs. Procedure-related AEs and serious AEs were reported in 63.7% (392/615) and 11.7% (72/615) of the total patient cohort, respectively. The OS rate at 12 months was 95.5% (95% CI, 92.8%-97.2%).

CONCLUSIONS

MWA is a safe and effective treatment for primary and metastatic liver tumors in a large, real-world patient population.

Current use of percutaneous ablation in renal tumors: an analysis of the registry of the German Society for Interventional Radiology and Minimally Invasive Therapy

OBJECTIVE

To evaluate the success and complications of thermal ablation (TA) based on the voluntary, prospective registry of the German Society for Interventional Radiology and Minimally Invasive Therapy (DeGIR) with 303 participating centers from Germany, Austria, and Switzerland.

MATERIALS AND METHODS

Registry data from 2018 until 2023 of 1102 patients with small renal tumors (age: 72.5 ± 11.6 years; female: 33.6%, 370/1102) were analyzed. Hospitals with ≥ 20 TAs were considered high-volume centers. Technical success and complication rates between different parameters were compared using the chi-square or Fisher's exact test, p < 0.05 was considered statistically significant.

RESULTS

Patients were most frequently treated with radiofrequency ablation (RFA, 43.6%, 481/1102), then microwave ablation (MWA, 41.9%, 462/1102) or cryoablation (13.3%, 147/1102). Technical success for heat-based TA (RFA&MWA) was 94.3% (893/947), for cryoablation 97.3% (143/147). RFA&MWA was significantly more successful in lesions ≤ 3 cm (96.1%, 567/590) compared to 3-4 cm lesions (89.8%, 97/108; p = 0.005). In patients treated with cryoablation, no significant differences between sizes could be found (≤ 3 cm: 97.9%, 94/96; 3-4 cm: 85.7%, 12/14; p = 0.078). Complication rate was significantly higher in RFA&MWA of lesions 3-4 cm compared to ≤ 3 cm (≤ 3 cm: 3.9%, 23/590; 3-4 cm: 11.1%, 12/108, p = 0.002), while no significant differences were seen regarding cryoablation (≤ 3 cm: 1.0%, 1/96; 3-4 cm: 0.0%, 0/14; p = 1.000).

CONCLUSIONS

In this exploratory analysis of the DeGIR registry, percutaneous TA of small renal masses is technically feasible with low complication rates. Heat-based TAs seem to have lower success rates and higher complication rates in larger tumors. Cryoablation could potentially be a safe alternative for 3- to 4-cm-sized tumors.

KEY POINTS

Question How effective is renal thermal ablation (TA) in terms of treatment success and complication rates? Findings In contrast to cryoablation, heat-based thermal ablation has lower success and higher complication rates in tumors measuring 3-4 cm compared to tumors < 3 cm. Clinical relevance Thermal ablation is not influenced by the need for additional techniques such as cooling, protective organ displacement, or temporary vessel occlusion. For small renal tumors, TA is an effective and safe treatment option. Cryoablation could be beneficial in larger tumors.

Endovascular Treatment of Visceral Artery Aneurysms: Data Analysis of the DeGIR/DGNR Quality Management System

Visceral artery aneurysms (VAA) are rare, and data on their occurrence and treatment are often outdated or heterogeneous. The objective of this study is to provide a comprehensive overview of features and interventional treatment options for VAA.We analyzed demographic, procedural, and clinical data on VAA from 2018 to 2022 based on data derived from the German Society for Interventional Radiology and Minimally Invasive Therapy (DeGIR) registry regarding demographic details, aneurysm characteristics, treatment processes, and outcomes such as technical success, complication rates, and radiation exposure. Group comparisons between aneurysm locations and types were calculated as dependent variables as well as occurrence of incomplete embolization, complication rates, technical success, duration of intervention, and dose-area-product (DAP).In total 647 patients were enrolled. The mean age was 66 years, with 68.5% male. The most affected arteries were splenic (27.5%) and renal (21.3%). True aneurysms were most common (56.7%). Technical success was 91.2%, while primary incomplete embolization occurred in 47.3%. Complications were observed in 4.8%, with a 0.2% mortality. Mean intervention duration was 67 min, mean fluoroscopic time was 36 min and mean DAP was 9560 cGycm2. There were no significant differences in primary incomplete embolization, complication rate, correct placement of embolization material, duration, and DAP based on aneurysm location. Aneurysm types showed a significant difference in incomplete embolization, with dissections having the highest rates and longest durations of intervention and highest DAP.The analysis of DeGIR quality management data reveals consistently high technical success and low complication rates in endovascular treatment of VAA. Dissecting aneurysms exhibit the highest rates in incomplete embolization, requiring the longest interventions and increased radiation. Enhancing the DeGIR registry with follow-up features would benefit assessing VAA occlusion rates. The data provide a comprehensive nationwide overview of how interventional radiology can impact treatment strategy. · Visceral artery aneurysms represent a rare entity. · The DeGIR registry provides extensive data about rare endovascular treatments of visceral artery aneurysms. · Endovascular treatment of visceral aneurysms is feasible and safe. · Dissecting aneurysms are associated with the highest rates of primary incomplete embolization and the longest interventional durations. · Weiss D, Jannusch K, Wilms LM et al. Endovascular Treatment of Visceral Artery Aneurysms: Data Analysis of the DeGIR/DGNR Quality Management System. Rofo 2025; DOI 10.1055/a-2513-1135.

Oncologic Outcomes after Percutaneous Ablation for Colorectal Liver Metastases: An Updated Comprehensive Review

Colorectal cancer is a major cause of cancer-related mortality, with liver metastases occurring in over a third of patients, and is correlated with poor prognosis. Despite surgical resection being the primary treatment option, only about 20% of patients qualify for surgery. Current guidelines recommend thermal ablation either alone or combined with surgery to treat limited hepatic metastases, provided that all visible disease can be effectively eradicated. Several ablation modalities, including radiofrequency ablation, microwave ablation, cryoablation, irreversible electroporation and histotripsy, are part of the percutaneous ablation armamentarium. Thermal ablation, including radiofrequency, microwave ablation and cryoablation, can offer local tumor control rates comparable to limited resection for selected tumors that can be ablated with margins. This review aims to encapsulate the current clinical evidence regarding the efficacy and oncologic outcomes after percutaneous ablation for the treatment of colorectal liver metastatic disease.