The learning curve of laparoscopic ablation of liver tumors: A technically demanding procedure requiring dedicated training

Local recurrence risk factors and outcomes in minimally invasive thermal ablation for liver tumors: a single-institution analysis

BACKGROUND

Minimally Invasive thermal ablation (MITA) of liver tumors is a commonly performed procedure, alone or in combination with liver resection. Despite being a first-option strategy for small lesions, it is technically demanding, and many concerns still exist about local disease control.

METHODS

Consecutive patients undergoing MITA from 1-2019 to 12-2022 were retrospectively enrolled. Risk factors of local recurrence were investigated through univariate and multivariable cox regression analysis.

RESULTS

At the multivariable analysis of the 207 nodules undergoing MITA, RFA was associated with worse local Recurrence Free Survival (lRFS) than MWA (HR 2.87 [95 % CI 0.96-8.66], p = 0.05), as well as a concomitant surgical resection (HR 3.89 [95 % CI 1.06-9.77], p = 0.02). A concomitant surgical resection showed worse lRFS in the subgroup analysis of both HCC (HR 3.98 [95 % CI 1.16-13.62], p = 0.02) and CRLM patients (HR 2.68 [95 % CI 0.66-5.92], p = 0.04). Interestingly, a tumor size between 30 and 40 mm was not associated to worse lRFS.

CONCLUSION

MWA may reduce the risk of local recurrence in comparison to RFA, while MITA associated to liver resection may face an increased risk of local recurrence. Further prospective studies are needed to confirm such results.

The influence of microwave ablation parameters on the positioning of trocar in different cancerous tissues: a numerical study

The present study analyzed the microwave ablation of cancerous tumors located in six major cancer-prone organs and estimated the significance of input power and treatment time parameters in the apt positioning of the trocar into the tissue during microwave ablation. The present study has considered a three-dimensional two-compartment tumour-embedded tissue model. FEA based COMSOL Multiphysics software with inbuilt bioheat transfer, electromagnetic waves, heat transfer in solids and fluids, and laminar flow physics has been used to obtain the numerical results. Based on the mortality rates caused by cancer, the present study has considered six major organs affected by cancer, viz. lung, breast, stomach/gastric, liver, liver (with colon metastasis), and kidney for MWA analysis. The input power (100 W) and ablation times (4 minutes) with apt and inapt positioning of the trocar have been considered to compare the ablation volume of various cancerous tissues. The present study addresses one of the major problems clinicians face, i.e. the proper placement of the trocar due to poor imaging techniques and human error, resulting in incomplete tumor ablation and increased surgical procedures. The highest values of the ablation region have been observed for the liver, colon metastatic liver and breast cancerous tissues compared with other organs at the same operating conditions.

Integrating Navigation-Assisted Ablation in the Locoregional Treatment of Hepatocellular Carcinoma

Importance

With the increasing prevalence of hepatocellular carcinoma (HCC), ablative therapy is a critical treatment option to achieve a cancer-free state. The anatomic location of the tumor can be a challenge, and select hepatic locations of a tumor require laparoscopic-assisted strategies to safely reach and treat the lesion.

Objective

To assess the association of real-time ultrasonography-augmented navigation for HCC ablation with patient survival, operative time, and rate of incomplete ablations.

Design, Setting, and Participants

This retrospective case-control study was conducted among a prospectively collected database of more than 750 patients with HCC who were treated with ablation therapy with and without the use of navigation at a single quaternary medical center from June 2011 to January 2021. Data were analyzed from October 2022 through June 2023.

Exposure

Real-time ultrasonography-augmented navigation.

Main Outcomes and Measures

The primary outcome was rate of incomplete ablations in patients undergoing HCC ablation with vs without navigation. Secondary outcomes included overall survival (OS), progression-free survival (PFS), and operative time.

Results

The analytic cohort included 467 patients (mean [SD] age, 62.4 [7.8] years; 355 male [76.0%]; 21 Hispanic [4.5%], 67 non-Hispanic Black [14.5%], and 347 Non-Hispanic White [75.0%] among 463 patients with race and ethnicity data). The most common etiology of liver disease was hepatitis C infection (187 patients with etiology data [40.0%]), and 348 of 458 patients with TMN staging data (76.0%) had TNM stage 1 disease. There were 187 individuals treated with navigation and 280 individuals treated without navigation. Patients who underwent navigation-assisted ablation were more likely to have stage 2 disease based on TNM staging (62 of 183 patients [33.9%] vs 47 of 275 patients [17.1%] with TMN data; P < .002) and had a higher mean (SD) number of lesions (1.3 [0.5] vs 1.2 [0.5] lesions; P = .002) and a longer mean (SD) operation time (113.2 [29.4] vs 109.6 [32.3] minutes; P = .04). Patients who underwent navigation were also more likely to have tumors in segment 8 (59 patients [32.1%] vs 53 of 275 patients with segment data [19.3%] with segment data; P = .005) and less likely to have tumors in segment 4 (20 patients [10.9%] vs 54 patients with segment data [19.6%]; P = .005). Overall mean (SD) time to recurrence after treatment was 10.0 (12.5) months, with similar rates for patients with navigation vs no navigation. There were no differences in incomplete ablation rate (10 patients [9.2%] vs 10 patients [10.5%]; P = .32), OS, or PFS between patients undergoing ablation with and without navigation.

Conclusions and Relevance

In this study, use of navigation was associated with comparable outcomes to undergoing ablation without navigation, although patients with navigation had more locally advanced disease. These findings suggest that use of real-time navigation in laparoscopic-assisted ablation of liver cancer should be considered as a useful tool for treating challenging tumors.

Intra-operative High-Intensity Focused Ultrasound in Patients With Colorectal Liver Metastases: A Prospective Ablate-and-Resect Study

OBJECTIVE

High-intensity focused ultrasound (HIFU) is a recent, non-ionizing and non-invasive technology of focal destruction. Independence from the heat-sink effect of blood flow makes HIFU an interesting technique for focal ablation of liver tumors. Current available technology is based on extracorporeal treatment that limits use of HIFU for the treatment of liver tumors, as elementary ablations are small and must be juxtaposed to treat tumors, resulting in long-duration treatment. We developed an HIFU probe with toroidal technology, which increases the volume of ablation, for intra-operative use, and we assessed the feasibility and efficacy of this device in patients with colorectal liver metastasis (CLM) measuring less than 30 mm.

METHODS

This study was an ablate-and-resect, prospective, single-center, phase II study. All ablations were performed in the area of liver scheduled for liver resection to avoid loss of chance of recovery. The primary objective was to ablate CLM with safety margins (>5 mm).

RESULTS

Between May 2014 and July 2020, 15 patients were enrolled and 24 CLM were targeted. The HIFU ablation time was 370 s. In total, 23 of 24 CLM were successfully treated (95.8%). No damage occurred to extrahepatic tissues. HIFU ablations were oblate shaped with an average long axis of 44.3 ± 6.1 mm and an average shortest axis of 35.9 ± 6.7 mm. On pathological examination, the average diameter of the treated metastasis was 12.2 ± 4.8 mm.

CONCLUSION

Intra-operative HIFU can safely and accurately produce large ablations in 6 min with real-time guidance (ClinicalTrials.gov identifier: NCT01489787).

Laparoscopic Microwave Ablation: Which Technologies Improve the Results

Liver resection is the best treatment for hepatocellular carcinoma (HCC) when resectable. Unfortunately, many patients with HCC cannot undergo liver resection. Percutaneous thermoablation represents a valid alternative for inoperable neoplasms and for small HCCs, but it is not always possible to accomplish it. In cases where the percutaneous approach is not feasible (not a visible lesion or in hazardous locations), laparoscopic thermoablation may be indicated. HCC diagnosis is commonly obtained from imaging modalities, such as CT and MRI, However, the interpretation of radiological images, which have a two-dimensional appearance, during the surgical procedure and in particular during laparoscopy, can be very difficult in many cases for the surgeon who has to treat the tumor in a three-dimensional environment. In recent years, more technologies have helped surgeons to improve the results after ablative treatments. The three-dimensional reconstruction of the radiological images has allowed the surgeon to assess the exact position of the tumor both before the surgery (virtual reality) and during the surgery with immersive techniques (augmented reality). Furthermore, indocyanine green (ICG) fluorescence imaging seems to be a valid tool to enhance the precision of laparoscopic thermoablation. Finally, the association with laparoscopic ultrasound with contrast media could improve the localization and characteristics of tumor lesions. This article describes the use of hepatic three-dimensional modeling, ICG fluorescence imaging and laparoscopic ultrasound examination, convenient for improving the preoperative surgical preparation for personalized laparoscopic approach.

Selecting the Best Approach for the Treatment of Multiple Non-Metastatic Hepatocellular Carcinoma

According to the Barcelona Clinic Liver Cancer (BCLC) staging system, the optimal strategy for patients with multiple HCC within the Milan Criteria is liver transplantation (LT). However, LT cannot be offered to all the patients due to organ shortages and long waiting lists, as well as because of the advanced disease carrying a high risk of poor outcomes. For early stages, liver resection (LR) or thermal ablation (TA) can be proposed, while trans-arterial chemoembolization (TACE) still remains the treatment of choice for intermediate stages (BCLC-B). Asian guidelines and the National Comprehensive Cancer Network suggest LR for resectable multinodular HCCs, even beyond Milan criteria. In this scenario, a growing body of evidence shows better outcomes after surgical resection when compared with TACE. Trans-arterial radioembolization (TARE) and stereotaxic body radiation therapy (SBRT) can also play an important role in this setting. Furthermore, the role of minimally invasive liver surgery (MILS) specifically for patients with multiple HCC is still not clear. This review aims to summarize current knowledge about the best therapeutical strategy for multiple HCC while focusing on the role of minimally invasive surgery and on the most attractive future perspectives.