Multiple imaging modality-guided radiofrequency ablation combined with transarterial chemoembolization for hepatocellular carcinoma in special locations

CT-guided percutaneous chemical ablation combined with radiofrequency ablation for hepatocellular carcinomas in high-risk locations: lobaplatin vs. ethanol

To retrospectively compare the clinical efficacy and safety of CT-guided percutaneous injection of lobaplatin vs. ethanol for chemical ablation combined with radiofrequency ablation (RFA) in patients with hepatocellular carcinomas (HCCs) in high-risk locations. From January 2017 to June 2018, a total of 41 patients with HCCs in high-risk locations were enrolled and divided into two groups: percutaneous lobaplatin injection (PLI+RFA) group and percutaneous ethanol injection (PEI+RFA) group. The mixture of lobaplatin or ethanol was accurately injected into the high-risk part of the tumors, while RFA ablated the non-high-risk part. The efficacy and safety were compared between the two groups. 41 patients had 51 lesions in high-risk locations, including 24 cases with 30 lesions in PLI+RFA group and 17 cases with 21 lesions in PEI+RFA group. The complete ablation rate was 93.3% (28/30) in PLI+RFA group and 90.5% (19/21) in PEI+RFA group (P=1.000). The 2-year local tumor progression rate of PLI+RFA group and PEI+RFA group was 20.0% (6/30) and 19.0% (4/21), respectively (P=1.000). No significant differences were found in time to progression and overall survival between the two groups (P=0.501 and P=0.424, respectively). The incidence and severity of adverse events between the two groups were similar (P > 0.05). No severe complications were observed in both groups. Percutaneous lobaplatin injection combined with RFA in the treatment of HCC in high-risk locations may achieve the complete ablation rate similar to percutaneous ethanol injection combined with RFA, but further research is needed to confirm.

Combined treatments in hepatocellular carcinoma: Time to put them in the guidelines?

The time for battling cancer has never been more suitable than nowadays and fortunately against hepatocellular carcinoma (HCC) we do have a far-reaching arsenal. Moreover, because liver cancer comprises a plethora of stages-from very early to advanced disease and with many treatment options–from surgery to immunotherapy trials–it leaves the clinician a wide range of options. The scope of our review is to throw light on combination treatments that seem to be beyond guidelines and to highlight these using evidence-based analysis of the most frequently used combination therapies, discussing their advantages and flaws in comparison to the current standard of care. One particular combination therapy seems to be in the forefront: Transarterial chemoembolization plus ablation for medium-size non-resectable HCC (3-5 cm), which is currently at the frontier between Barcelona Clinic Liver Cancer classification A and B. Not only does it improve the outcome in contrast to each individual therapy, but it also seems to have similar results to surgery. Also, the abundance of immune checkpoint inhibitors that have appeared lately in clinical trials are bringing promising results against HCC. Although the path of combination therapies in HCC is still filled with uncertainty and caveats, in the following years the hepatology and oncology fields could witness an HCC guideline revolution.

Assessment of Ablative Margin After Microwave Ablation for Hepatocellular Carcinoma Using Deep Learning-Based Deformable Image Registration

Aim: To assess the ablative margin (AM) after microwave ablation (MWA) for hepatocellular carcinoma (HCC) with a deep learning-based deformable image registration (DIR) technique and analyze the relation between the AM and local tumor progression (LTP).

Patients and Methods: From November 2012 to April 2019, 141 consecutive patients with single HCC (diameter ≤ 5 cm) who underwent MWA were reviewed. Baseline characteristics were collected to identify the risk factors for the determination of LTP after MWA. Contrast-enhanced magnetic resonance imaging scans were performed within 1 month before and 3 months after treatment. Complete ablation was confirmed for all lesions. The AM was measured based on the margin size between the tumor region and the deformed ablative region. To correct the misalignment, DIR between images before and after ablation was achieved by an unsupervised landmark-constrained convolutional neural network. The patients were classified into two groups according to their AMs: group A (AM ≤ 5 mm) and group B (AM > 5 mm). The cumulative LTP rates were compared between the two groups using Kaplan–Meier curves and the log-rank test. Multivariate analyses were performed on clinicopathological variables to identify factors affecting LTP.

Results: After a median follow-up period of 28.9 months, LTP was found in 19 patients. The mean tumor and ablation zone sizes were 2.3 ± 0.9 cm and 3.8 ± 1.2 cm, respectively. The mean minimum ablation margin was 3.4 ± 0.7 mm (range, 0–16 mm). The DIR technique had higher AUC for 2-year LTP without a significant difference compared with the registration assessment without DL (P = 0.325). The 6-, 12-, and 24-month LTP rates were 9.9, 20.6, and 24.8%, respectively, in group A, and 4.0, 8.4, and 8.4%, respectively, in group B. There were significant differences between the two groups (P = 0.011). Multivariate analysis showed that being >65 years of age (P = 0.032, hazard ratio (HR): 2.463, 95% confidence interval (CI), 1.028–6.152) and AM ≤ 5 mm (P = 0.010, HR: 3.195, 95% CI, 1.324–7.752) were independent risk factors for LTP after MWA.

Conclusion: The novel technology of unsupervised landmark-constrained convolutional neural network-based DIR is feasible and useful in evaluating the ablative effect of MWA for HCC.