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

Abstract

Background: Stereotactic navigation techniques aim to enhance treatment precision and safety in minimally invasive thermal ablation of liver tumours. We qualitatively reviewed and quantitatively summarised the available literature on procedural and clinical outcomes after stereotactic navigated ablation of malignant liver tumours.Methods: A systematic literature search was performed on procedural and clinical outcomes when using stereotactic or robotic navigation for laparoscopic or percutaneous thermal ablation. The online databases Medline, Embase and Cochrane Library were searched. Endpoints included targeting accuracy, procedural efficiency and treatment efficacy outcomes. Meta-analysis including subgroup analyses were performed.Results: Thirty-four studies (2 randomised controlled trials, 3 prospective cohort studies, 29 case series) were qualitatively analysed and 22 studies included for meta-analysis. Weighted average lateral targeting error was 3.7mm (CI 3.2,4.2), with all four comparative studies showing enhanced targeting accuracy compared to free-hand targeting. Weighted average overall complications, major complications and mortality were 11.4% (6.7, 16.1), 3.4% (2.1, 5.1) and 0.8% (0.5, 1.3). Pooled estimates of primary technique efficacy were 94% (89, 97) if assessed at 1 – 6 weeks and 90% (87, 93) if assessed at 6 – 12 weeks post ablation, with significant remaining between-study heterogeneity. Pooled odds ratio of primary technique efficacy for stereotactic versus free-hand targeting was 1.9 (1.2, 3.2)(n = 6 studies).Conclusions: Advances in stereotactic navigation technologies allow highly precise and safe tumour targeting, potentially leading to enhanced early treatment efficacy. The use of varying definitions and terminology limit comparability of safety and efficacy among studies, highlighting the crucial need for further standardization of follow-up definitions.

Volumetric Quantitative Ablation Margins for Assessment of Ablation Completeness in Thermal Ablation of Liver Tumors

“…It is of no doubt that the introduction of novel technologies such as SMWA and QAM bring additional efforts in the set-up and interventional workflows, the main challenge representing an optimal training of staff, after which learning curves are relatively fast and additional efforts can be reduced ( 34 ). First comparative studies further suggest enhanced treatment efficacy when using navigated ablation as opposed to conventional targeting ( 35 ), hence, overall treatment costs might be compensated if frequent re-treatments can be avoided. In conclusion, this work presents and publicly displays an algorithm for volumetric quantitative margin computation to assess ablation completeness after thermal ablation of liver tumors, including a novel algorithm to address subcapsular tumors.…”