Electromagnetic navigation system for CT-guided percutaneous abdominal tumour ablation: Safety and effectiveness

Abstract

Objectives

To assess the impact of radiologist experience on the technical success, safety and effectiveness of CT-guided thermal ablation (TA) procedures for abdominal tumors, including hepatocellular carcinomas (HCCs), colorectal cancer liver metastases (CRLMs), and renal cell carcinomas (RCCs), when assisted by an electromagnetic navigation system (EMNS).

Material and methods

We retrospectively collected data for patients who had undergone CT-guided TA between 2020 and 2022, recording the characteristics of the lesions. Lesions were considered high-risk if they were located in the subphrenic or subcapsular areas of the liver or less than 1 cm from the bowel, bile duct, portal vein, vena cava or gallbladder and those located in the kidney in the anterior leaflet or close to the urinary tract. The radiologists who performed the procedures were classified according to whether they had more or less experience (more or less than five years of experience in percutaneous TA). Technical success was assessed immediately after treatment. Procedure data, response and complication rates were recorded.

Results

A total of 139 tumors were treated in 105 ablation sessions in 93 patients, consisting of 69 men and 24 women. Sixty-two percent of the tumors were HCCs, 27% were CRLMs, and 12% were RCCs. The median tumor size was 16 mm. A total of 68% of the tumors were located in high-risk areas. The technical success rate was 96.4%, with minor complications occurring in 20% of the procedures and major complications in 3.8%. The median follow-up was 12 months. The complete response rates were 96.6%, 93.1%, and 86.2% at 3, 6, and 12 months, respectively. There were no significant differences in response at one month (p = 0.706) or one year (p = 0.402), complications (p = 0.583), procedure time (p = 0.729), or the number of follow-up CT scans (p = 0.208) between more and less experienced radiologists.

Conclusion

An EMNS enhances accuracy and standardisation in interventional procedures, enabling precise ablations, regardless of the radiologist's experience or location involved.