<abstract xmlns="http://www.w3.org/1999/xhtml"><sec id="j_raon-2020-0004_s_005_w2aab3b8c32b1b7b1aab1c16b1Aa"><h3>Background</h3><p>The aim of the study was to evaluate the inter- and intrareader variability of the safety margin assessment after microwave ablation of liver tumors using post-procedure computed tomography (CT) images as well as to determine the sensitivity and specificity of identification remnant tumor tissue.</p></sec><sec id="j_raon-2020-0004_s_006_w2aab3b8c32b1b7b1aab1c16b2Aa"><h3>Patients and methods</h3><p>A retrospective analysis of 58 patients who underwent microwave ablation (MWA) of primary or secondary liver malignancies (46 hepatocellular carcinoma, 9 metastases of a colorectal cancer and 3 metastases of pancreatic cancer) between September 2017 and June 2019 was conducted. Three readers estimated the minimal safety margin in millimeters using side-by-side comparison of the 1-day pre-ablation CT and 1-day post-ablation CT and judged whether ablation was complete or incomplete. One reader estimated the safety margin again after 6 weeks. Magnetic resonance imaging (MRI) after 6 weeks was the gold standard.</p></sec><sec id="j_raon-2020-0004_s_007_w2aab3b8c32b1b7b1aab1c16b3Aa"><h3>Results</h3><p>The intraclass correlation coefficient (ICC) for estimation of the minimal safety margin of all three readers was 0.357 (95%-confidence interval 0.194–0.522). The ICC for repeated assessment (reader 1) was 0.774 (95%-confidence interval 0.645–0.860). Sensitivity and specificity of the detection of complete tumor ablation, defined as no remnant tumor tissue in 6 weeks follow-up MRI, were 93%/82%/82% and 33%/17%/83%, respectively.</p></sec><sec id="j_raon-2020-0004_s_008_w2aab3b8c32b1b7b1aab1c16b4Aa"><h3>Conclusions</h3><p>In clinical practice, the safety margin after liver tumor ablation is often assessed using side-by-side comparison of CT images. In the study, we were able to show, that this technique has a poor reliability (ICC 0.357). From our point of view, this proves the necessity of new technical procedures for the assessment of the safety distance.</p></sec></abstract>

BackgroundThe aim of the study was to evaluate the inter- and intrareader variability of the safety margin assessment after microwave ablation of liver tumors using post-procedure computed tomography (CT) images as well as to determine the sensitivity and specificity of identification remnant tumor tissue.Patients and methodsA retrospective analysis of 58 patients who underwent microwave ablation (MWA) of primary or secondary liver malignancies (46 hepatocellular carcinoma, 9 metastases of a colorectal cancer and 3 metastases of pancreatic cancer) between September 2017 and June 2019 was conducted. Three readers estimated the minimal safety margin in millimeters using side-by-side comparison of the 1-day pre-ablation CT and 1-day post-ablation CT and judged whether ablation was complete or incomplete. One reader estimated the safety margin again after 6 weeks. Magnetic resonance imaging (MRI) after 6 weeks was the gold standard.ResultsThe intraclass correlation coefficient (ICC) for estimation of the minimal safety margin of all three readers was 0.357 (95%-confidence interval 0.194–0.522). The ICC for repeated assessment (reader 1) was 0.774 (95%-confidence interval 0.645–0.860). Sensitivity and specificity of the detection of complete tumor ablation, defined as no remnant tumor tissue in 6 weeks follow-up MRI, were 93%/82%/82% and 33%/17%/83%, respectively.ConclusionsIn clinical practice, the safety margin after liver tumor ablation is often assessed using side-by-side comparison of CT images. In the study, we were able to show, that this technique has a poor reliability (ICC 0.357). From our point of view, this proves the necessity of new technical procedures for the assessment of the safety distance.

Safety margin assessment after microwave ablation of liver tumors: inter- and intrareader variability

Radiology and Oncology

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BackgroundThe aim of the study was to evaluate the inter- and intrareader variability of the safety margin assessment after microwave ablation of liver tumors...

Safety margin assessment after microwave ablation of liver tumors: inter- and intrareader variability

Article Category: Research Article

Published Online: Feb 12, 2020

Page range: 57 - 61

Received: Sep 16, 2019

Accepted: Jan 10, 2020

DOI: https://doi.org/10.2478/raon-2020-0004

© 2020 Jan Schaible, Benedikt Pregler, Wolf Bäumler, Ingo Einspieler, Ernst-Michael Jung, Christian Stroszczynski, Lukas Philipp Beyer, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.