ABSTRACT
Objective. This study aims to develop and assess a tumor contraction model, enhancing the precision of ablative margin (AM) evaluation after microwave ablation (MWA) treatment for hepatocellular carcinomas (HCCs).Approach. We utilize a probabilistic method called the coherent point drift algorithm to align pre-and post-ablation MRI images. Subsequently, a nonlinear regression method quantifies local tumor contraction induced by MWA, utilizing data from 47 HCC with viable ablated tumors in post-ablation MRI. After automatic non-rigid registration, correction for tumor contraction involves contracting the 3D contour of the warped tumor towards its center in all orientations.Main results. We evaluate the performance of our proposed method on 30 HCC patients who underwent MWA. The Dice similarity coefficient between the post-ablation liver and the warped pre-ablation livers is found to be 0.95 ± 0.01, with a mean corresponding distance between the corresponding landmarks measured at 3.25 ± 0.62 mm. Additionally, we conduct a comparative analysis of clinical outcomes assessed through MRI over a 3 month follow-up period, noting that the AM, as evaluated by our proposed method, accurately detects residual tumor after MWA.Significance. Our proposed method showcases a high level of accuracy in MRI liver registration and AM assessment following ablation treatment. It introduces a potentially approach for predicting incomplete ablations and gauging treatment success.
Subject(s)
Carcinoma, Hepatocellular , Catheter Ablation , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/surgery , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Microwaves/therapeutic use , Catheter Ablation/methods , Tomography, X-Ray Computed/methods , Treatment Outcome , Magnetic Resonance Imaging/methods , Retrospective StudiesABSTRACT
PURPOSE: We aimed to explore the feasibility of microwave ablation (MWA) assisted by three-dimensional visualization system for relapsed HB in children. METHODS: From August 2014 to February 2017, five patients with relapsed HB were enrolled. A total of 12 liver tumors were treated with MWA assisted by a three-dimensional visualization system. Follow-up data were obtained in all patients. The residual liver volume, local tumor progression, new intrahepatic tumors, survival outcome, and complications were analyzed. RESULTS: All tumors were completely ablated in a single session. The mean ablation time per tumor was 9.7 ± 8.6 min, and the median ablation/liver volume ratio was 2.37%. No local tumor progression was observed during a follow-up period of 9-39 months. All patients were still alive at the end of the follow-up. The median progression-free survival time after ablation was 9 months, and the median survival time after ablation was 12 months. No other complications were observed except for fever. CONCLUSIONS: MWA assisted by three-dimensional visualization system appears to be a safe and feasible local treatment for recurrent HB in pediatric patients.
Subject(s)
Catheter Ablation/methods , Hepatoblastoma/diagnostic imaging , Hepatoblastoma/surgery , Imaging, Three-Dimensional , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Magnetic Resonance Imaging , Microwaves/therapeutic use , Adolescent , Child , Child, Preschool , Disease Progression , Feasibility Studies , Female , Hepatoblastoma/mortality , Humans , Liver Neoplasms/mortality , Male , Retrospective Studies , Survival RateABSTRACT
PURPOSE: To evaluate the effects of ablation strategies on local tumor progression (LTP) after microwave ablation (MWA) of hepatocellular carcinomas (HCCs) measuring 3-5 cm. MATERIALS AND METHODS: Between December 2011 and May 2017, 71 HCC patients with 71 nodules treated by ultrasound(US)-guided percutaneous MWA were divided into parallel (group A) and crossed (group B) antenna placement groups. All patients underwent MWA using two antennas with four insertions. LTP and overall survival (OS) rates were compared between the two groups. RESULTS: The median follow-up time was 16.8 months. There was no significant difference in the complete ablation rate and treatment sessions between the two groups. LTP was diagnosed in 8 of 48 nodules (16.7%) in group A and 1 of 23 nodules (4.3%) in group B, with no significant difference between two groups (P = 0.115). The 1-, 2-, and 3-year OS rates were 88.5%, 79%, and 71.8% in group A and 93.8%, 87.5%, and 87.5% in group B, respectively (P = 0.236). Multivariate analysis showed that the tumor diameter (P = 0.017), the distance between the antennas (P = 0.032), and the total emission time (P = 0.015) were associated with LTP. CONCLUSIONS: There were trends with lower LTP and improved OS in group B, despite the lack of statistically significant differences between the two strategies at a level of P < 0.05. The increase of distance between antennas and total emission time will facilitate reductions in LTP rate.
