Improvement of the primary efficacy of microwave ablation of malignant liver tumors by using a robotic navigation system

Abstract

BackgroundThe aim of the study was to assess the primary efficacy of robot-assisted microwave ablation and compare it to manually guided microwave ablation for percutaneous ablation of liver malignancies.Patients and methodsWe performed a retrospective single center evaluation of microwave ablations of 368 liver tumors in 192 patients (36 female, 156 male, mean age 63 years). One hundred and nineteen ablations were performed between 08/2011 and 03/2014 with manual guidance, whereas 249 ablations were performed between 04/2014 and 11/2018 using robotic guidance. A 6-week follow-up (ultrasound, computed tomography and magnetic resonance imaging) was performed on all patients.ResultsThe primary technique efficacy outcome of the group treated by robotic guidance was significantly higher than that of the manually guided group (88% vs. 76%; p = 0.013). Multiple logistic regression analysis indicated that a small tumor size (≤ 3 cm) and robotic guidance were significant favorable prognostic factors for complete ablation.ConclusionsIn addition to a small tumor size, robotic navigation was a major positive prognostic factor for primary technique efficacy.

Stereotactic and Robotic Minimally Invasive Thermal Ablation of Malignant Liver Tumours - A Systematic Review and Meta-Analysis

“…All of the 34 included works were single-centre studies, of which 26 were retrospective studies (29,30,(39)(40)(41)(42)(43)(44)(45)(46)(47)(48)31,(49)(50)(51)(52)(53)(54)(32)(33)(34)(35)(36)(37)(38), 3 prospective case series(55-57), 3 prospective cohort studies(58-60) and 2 randomised controlled trials (61,62). Two studies reported results using a laparoscopic treatment access (44,55), the other 32 reporting on thermal ablations using a percutaneous approach.…”

“…Two studies reported results using a laparoscopic treatment access (44,55), the other 32 reporting on thermal ablations using a percutaneous approach. Six studies applied robotic targeting using mechanical tracking (31,47,48,51,60,62), 7 an electromagnetic (EM)-tracked dynamic technique (35,42,50,55,57,59,61) and the other 21 an optically tracked stereotactic aiming device. Baseline study, patient and lesion characteristics, applied ablation and navigation techniques and reported outcomes of the included works are shown in Table 2.…”

“…With respect to treatment e cacy, Zhang et al (42) showed a higher complete ablation rate in the rst session (3 days after ablation) when using stereotactic EM guidance, but equal primary technique e cacy at 1 month. Schaible et al (31) reported a signi cantly higher primary technique e cacy when using robotic targeting in a retrospective comparative study. The pooled odds ratio for stereotactic versus free-hand targeting was 1.94 (CI 1.18, 3.19) ( Figure 7).…”

“…Tinguely et al (29) showed a statistically signi cant in uence of tumour size (</> 3cm) and targeting accuracy (</> 5mm) on LTP, with no in uence by more complex intrahepatic tumour locations, in a multivariable model accounting for clustering by using Generalized Estimating Equation (GEE). Schaible et al reported tumour size (</> 3cm) next to the type of targeting approach (stereotactic vs. free-hand) to be a signi cant predictor of primary technique e cacy in a similar logistic GEE model (31). Lachenmayer et al (41) found vessel proximity and tumour size (</> 3cm) as independent predictors for LTP.…”

“…Varying de nitions were reported for all treatment e cacy outcomes, including the time points for assessment and the duration of follow-up. Six studies (29,31,41,42,53,61) referred to the terminology for follow-up assessment after ablation of liver tumours proposed by Ahmed et al (24), while thirteen studies applied similar de nitions without explicitly referencing this classi cation. Individual descriptions and time points of follow-up assessments are available for each study in the Supplementary File.…”