CT-guided navigated microwave ablation (MWA) of an unfavorable located breast cancer metastasis in liver segment I

For percutaneous minimally-invasive local ablation therapies of malignant lesions within the liver computed tomography (CT) fluoroscopy or ultrasound (US) can be applied for the positioning of ablation probes. However, lesions in liver segment I and in the upper part of liver segment VIII are difficult to reach with CT fluoroscopy and US guidance even for experienced interventionalists as steep and transcostal access paths may be needed. In addition, there is always the risk to lacerate crucial vessels near the liver hilus. We report on the use of a CT-based stereotactic navigation system (CAS-One, CAScination AG, Bern, Switzerland) for the precise positioning of the ablation probe to perform a percutaneous stereotactic image-guided microwave ablation of a breast cancer liver metastasis in liver segment I that was unreachable with conventional CT or US guidance. Based on the initial planning scan and image-to-patient registration a precise positioning of the probe was possible sparing vital structures like the directly adjacent vulnerable vessels. The ablation was performed without complications fully covering the metastatic lesion with the ablation zone. To this day, there was no recurring tumor 18 months after the intervention.