Copyright
©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
Liver magnetic resonance imaging for evaluation of response to treatment after stereotactic body radiation therapy of hepatocellular carcinoma
Alessandro Serafini, Valeria Ruggeri, Riccardo Inchingolo, Marco Gatti, Alessia Guarneri, Cesare Maino, Davide Ippolito, Luigi Grazioli, Umberto Ricardi, Riccardo Faletti
Alessandro Serafini, Marco Gatti, Riccardo Faletti, Department of Surgical Sciences, University of Turin, Turin 10126, Italy
Valeria Ruggeri, Department of Radiology, University of Brescia, Brescia 25123, Italy
Riccardo Inchingolo, Interventional Radiology Unit, Miulli Hospital, Acquaviva Delle Fonti 70124, Italy
Alessia Guarneri, Umberto Ricardi, Department of Oncology-Radiation Oncology, University of Turin, Turin 10126, Italy
Cesare Maino, Davide Ippolito, Department of Diagnostic Radiology, University of Milano-Bicocca, Monza 20900, Italy
Luigi Grazioli, Department of Radiology, Spedali Civili, University of Brescia, Brescia 25023, Italy
Author contributions: All authors equally contributed to this paper with conception and design of the study, literature review and analysis, manuscript drafting, critical revision, and editing, and approval of the final version.
Institutional review board statement: This retrospective observational study was previously approved by the Intercompany Ethics Committee of the City of Health and Science of Turin.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: All the authors are aware of the content of the manuscript and have no conflict of interest to disclose.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at riccardoin@hotmail.it. Consent was not obtained but the presented data are anonymized and risk of identification is low.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
https://creativecommons.org/Licenses/by-nc/4.0/ Corresponding author: Riccardo Inchingolo, MD, Chief Doctor, Director, Doctor, Interventional Radiology Unit, Miulli Hospital, Strada per Santeramo, Acquaviva Delle Fonti 70124, Italy. riccardoin@hotmail.it
Received: April 7, 2022
Peer-review started: April 7, 2022
First decision: May 29, 2022
Revised: June 24, 2022
Accepted: August 14, 2022
Article in press: August 14, 2022
Published online: September 27, 2022
BACKGROUND
Although stereotactic body radiation therapy (SBRT) is increasingly used, its application has not yet been regulated by the main international guidelines, leaving the decision to multidisciplinary teams.
AIM
To assess magnetic resonance imaging (MRI) features of hepatocellular carcinoma (HCC) treated with SBRT, highlighting the efficacy of the treatment and the main aspects of the lesion before and after the procedure.
METHODS
As part of a retrospective study, 49 patients who underwent SBRT for HCC between January 2013 and November 2019 were recruited. Each patient underwent a pre-treatment MRI examination with a hepatospecific contrast agent and a similar follow-up examination within 6 mo of therapy. In addition, 22 patients underwent a second follow-up examination after the first 6 mo. The following characteristics were analysed: Features analysed compared to pre-treatment MRI examination, presence or absence of infield and outfield progression, ring-like enhancement, signal hyperintensity in T2-weighted sequences in the perilesional parenchyma, capsular retraction, and "band" signal hypointensity in T1-weighted gradient echo fat saturated sequences obtained during hepatobiliary excretion.
RESULTS
Signal hyperintensity in the T2-weighted sequences showed a statistically significant reduction in the number of lesions at the post-SBRT first control (P = 0.0006). Signal hyperintensity in diffusion-weighted imaging-weighted sequences was decreased at MRI first control (P < 0.0001). A statistically significant increase of apparent diffusion coefficient values from a median of 1.01 to 1.38 at the first post-control was found (P < 0.0001). Capsular retraction was increased at the late evaluation (P = 0.006). Band-like signal hypointensity in the hepatobiliary phase was present in 94% at the late control (P = 0.006). The study of the risk of outfield progression vs infield progression revealed a hazard ratio of 9.
CONCLUSION
The efficacy of SBRT should be evaluated not in the first 6 mo, but at least 9 mo post-SBRT, when infield progression persists at very low rates while the risk of outfield progression increases significantly.
Core Tip: As part of a retrospective study, 49 patients who underwent stereotactic body radiation therapy (SBRT) for hepatocellular carcinoma between January 2013 and November 2019 were recruited. Each patient underwent a pre-treatment magnetic resonance imaging examination with a hepatospecific contrast agent and a similar follow-up examination within 6 mo of therapy. In addition, 22 patients underwent a second follow-up examination after the first 6 mo. The study results show that the efficacy of SBRT should be evaluated not in the first 6 mo, but at least 9 mo post-SBRT, when infield progression persists at very low rates while the risk of outfield progression increases significantly.
