Evidence on percutaneous radiofrequency and microwave ablation for liver metastases over the last decade

In-hospital outcomes of percutaneous ablative therapy for colorectal cancer liver metastasis in patients with and without frailty: nationwide inpatient sample analysis 2005-2020

Percutaneous ablative therapies are widely used to treat colorectal liver metastases (CRLM), particularly in patients who are not candidates for surgical resection. Frailty has been associated with poor outcomes in colorectal cancer (CRC) and liver resections. This study aimed to evaluate the clinical impact of frailty on short-term outcomes in patients undergoing percutaneous ablative therapies for CRLM. This population-based, retrospective study used data from the US Nationwide Inpatient Sample database (2005-2020). Adults aged ≥ 50 years diagnosed with CRLM who underwent percutaneous ablative therapies were included. Frailty was confirmed using the Hospital Frailty Risk Score (HFRS). Associations between frailty and in-hospital mortality, length of hospital stay (LOS), non-home discharge, total hospital charges, and postoperative complications were evaluated using univariate and multivariable regression analyses. A total of 670 patients (mean age: 66.3 years) were included, of whom 23% were categorized as frail (HFRS ≥ 5). Multivariable analysis showed that frail patients had significantly increased risks of complications (adjusted odds ratio [aOR] = 4.80, 95% confidence interval [CI]: 3.04-7.59), longer LOS (adjusted Beta [aBeta] = 1.69 days, 95% CI: 1.68-1.70), and higher total hospital charges (aBeta = $22.04 thousand, 95% CI: $21.92-$22.16). Complications with the highest risks in frail patients included, sepsis/shock (aOR = 17.39), surgical site infection (aOR = 3.55), respiratory failure/mechanical ventilation (aOR = 4.43), acute kidney injury (aOR = 9.37), and bleeding (aOR = 4.79). In conclusion, in adults aged ≥ 50 years undergoing percutaneous ablative therapies for CRLM, frailty independently predicted worse short-term outcomes, including higher complication rates, longer LOS, and increased hospital charges. The absence of detailed tumor characteristics and specific types of ablative therapy performed underscores the need for further research.

Impact of microwave ablation on survival rates and recurrence in hepatic malignant tumors

PURPOSE

This study aimed to evaluate the efficacy of percutaneous microwave ablation (MWA) for treating hepatic malignant tumors and to identify factors influencing tumor recurrence post-treatment.

METHODS

A total of 249 patients with hepatic malignant tumors treated at the Shandong Cancer Hospital and Institute were included, and 101 patients were analyzed. Disease-free and overall survival rates were assessed at 1, 2, and 3 years post-MWA. Correlations between tumor recurrence and factors such as Child-Pugh B classification and lesion count were examined, and a meta-analysis was conducted to identify independent risk factors for recurrence.

RESULTS

The study found disease-free survival rates of 80.2%, 72.3%, and 70.3% at 1, 2, and 3 years post-MWA, with overall survival rates at 99%, 97%, and 96%. Significant correlations were observed between tumor recurrence, Child-Pugh B classification, and the number of lesions. Meta-analysis confirmed lesion count and Child-Pugh B classification as independent risk factors for recurrence following MWA treatment.

CONCLUSION

The study underscores the importance of considering Child-Pugh B classification and lesion count in predicting tumor recurrence after MWA for hepatic malignant tumors. These findings offer valuable insights for clinicians in decision-making and post-treatment monitoring.

Ultrasound-guided intraoperative liver ablation - retrospective review of indications and outcomes

AIM

To define the indications and outcomes of intraoperative ablation of hepatic malignancies.

MATERIALS AND METHODS

This retrospective study comprises 27 patients (male/female: 19/8; mean age: 56 ± 13) undergoing intraoperative ablation (IOA) of liver tumours between July 2001 and August 2021 for 42 tumours, including colorectal liver metastasis (CRLM) (n = 27), hepatocellular carcinoma (HCC)(n = 14), and ovarian cancer metastasis (n = 1). The mean tumour diameter was 2.1 cm ± 1.3 (range, 0.6-5.6 cm). The median imaging follow-up was 26.3 months ± 25.6 (range: 0.13-161.6). Technical success (TS), local tumour progression (LTP), and local progression-free survival (LPFS) were calculated leveraging the Kaplan-Meier method. Adverse events (AE) were categorised according to SIR guidelines.

RESULTS

Indications for IOA include concurrent partial hepatectomy (n = 9), intraoperative detection of a new tumour (n = 4), lack of a safe percutaneous trajectory (n = 3) or clamp of hilum (n = 1). In 7 patients, surgeons made independent decisions for IOA not based on established criteria. Of 32 ablated tumours among 25 patients with available follow-up, TS was achieved for 31 tumours (97%). LTP was detected in 32% of cases at a median of 13.7 months. LPFS at 1,2,3,5 years were 82%, 60%, 51%, 51%. AE rate was 55.5% addressed with minimal or no interventions in 80% of cases. One patient with HCC died of liver failure.

CONCLUSION

The indications for IOA are concurrent partial hepatectomy, intraoperative detection of a new tumour, and suboptimal percutaneous ablation. IOA is effective with high TS. LTP is high. AE rate is relatively high; however, no significant treatment is required in most cases.

Applications of artificial intelligence in interventional oncology: An up-to-date review of the literature

Interventional oncology provides image-guided therapies, including transarterial tumor embolization and percutaneous tumor ablation, for malignant tumors in a minimally invasive manner. As in other medical fields, the application of artificial intelligence (AI) in interventional oncology has garnered significant attention. This narrative review describes the current state of AI applications in interventional oncology based on recent literature. A literature search revealed a rapid increase in the number of studies relevant to this topic recently. Investigators have attempted to use AI for various tasks, including automatic segmentation of organs, tumors, and treatment areas; treatment simulation; improvement of intraprocedural image quality; prediction of treatment outcomes; and detection of post-treatment recurrence. Among these, the AI-based prediction of treatment outcomes has been the most studied. Various deep and conventional machine learning algorithms have been proposed for these tasks. Radiomics has often been incorporated into prediction and detection models. Current literature suggests that AI is potentially useful in various aspects of interventional oncology, from treatment planning to post-treatment follow-up. However, most AI-based methods discussed in this review are still at the research stage, and few have been implemented in clinical practice. To achieve widespread adoption of AI technologies in interventional oncology procedures, further research on their reliability and clinical utility is necessary. Nevertheless, considering the rapid research progress in this field, various AI technologies will be integrated into interventional oncology practices in the near future.

Percutaneous radiofrequency ablation of liver metastases from colorectal cancer: Development of a prognostic score to predict overall survival

PURPOSE

To develop a model for pretreatment prediction of overall survival (OS) after radiofrequency ablation (RFA) for colorectal liver metastasis (CRLM).

METHOD

This retrospective study included 491 patients (median age, 61 years; 348 men) who underwent percutaneous RFA for CRLM between 2000 and 2021. The Kaplan-Meier method was used to estimate OS rates. Independent factors affecting OS were investigated using multivariable Cox regression analysis. Risk scores were assigned to the risk factors and pretreatment prediction models were created using the risk factors.

RESULTS

After RFA, the 5-, 10-, and 20-year OS rates were 44 %, 31 %, and 24 %, respectively, and the median OS was 46 months. Multivariate Cox regression analysis showed that a largest tumor size ≥ 2 cm (P<0.001), positive nodal status of primary tumor (P<0.001), carcinoembryonic antigen level > 30 ng/mL (P=0.049), multiple tumors (P=0.008), and T4 stage of the primary tumor (P=0.029) were independently associated with OS. In patients with a single CRLM, tumor diameter (P<0.001), positive nodal status of primary tumor (P=0.001), disease-free interval <12 months (P=0.045), and subcapsular location (P=0.03) were risk factors affecting OS. According to our prediction models, which included the aforementioned risk factors, OS rates progressively decreased as the risk scores increased, with significantly different OS rates between contiguous groups (P<0.001).

CONCLUSIONS

Our prediction models can be used as a prognostic stratification tool in patients with CRLM, and can help select those candidates who will benefit most from RFA.

Evaluation of an augmented reality navigational guidance platform for percutaneous procedures in a cadaver model

Purpose

The objective of this study is to review the accuracy of an augmented reality navigational guidance system designed to facilitate improved visualization, guidance, and accuracy during percutaneous needle-based procedures including biopsies and ablations.

Approach

Using the HoloLens 2, the system registers and projects 3D CT-based models of segmented anatomy along with live ultrasound, fused with electromagnetically tracked instruments including ultrasound probes and needles, giving the operator comprehensive stereoscopic visualization for intraoperative planning and navigation during procedures.Tracked needles were guided to targets implanted in a cadaveric model using the system. Image fusion registration error, the multimodality error measured as the post-registration distance between a corresponding point measured in the stereoscopic CT and tracked ultrasound coordinate systems, and target registration error, the Euclidean distance between needle tip and target after needle placement, were measured as registration and targeting accuracy metrics. A t-distribution was used for statistical analysis.

Results

Three operators performed 36 total needle passes, 18 to measure image fusion registration error and 18 to measure target registration error on four targets. The average depth of each needle pass was 8.4 cm from skin to target center. Mean IFRE was 4.4 mm (H 0 : μ = 5    mm , P < 0.05 ). Mean TRE was 2.3 mm (H 0 : μ = 5    mm , P < 0.00001 ).

Conclusions

The study demonstrated high registration and targeting accuracy of this AR navigational guidance system in percutaneous, needle-based procedures. This suggests the ability to facilitate improved clinical performance in percutaneous procedures such as ablations and biopsies.

Analysis of alkaline phosphatase and γ-glutamyltransferase after radiofrequency ablation of primary liver cancer: A retrospective study

BACKGROUND

Changes in alkaline phosphatase (ALP) and γ-glutamyltransferase (GGT) levels in patients with primary liver cancer (PLC) after radiofrequency ablation (RFA). Hepatocellular carcinoma is a malignant tumor with high incidence worldwide. As a common local treatment, RFA has attracted much attention for its efficacy and influence on liver function.

AIM

To investigate the effect of serum ALP and GGT levels on the prognosis of patients with PLC treated by RFA.

METHODS

The preoperative clinical data of 165 patients who were pathologically or clinically diagnosed with PLC and who received RFA in our hospital between October 2018 and June 2023 were collected. The chi-square test was used to compare the data between groups. The Kaplan-Meier method and Cox regression were used to analyze the associations between serum ALP and GGT levels and overall survival, progression-free survival (PFS) and clinical characteristics of patients before treatment.

RESULTS

The 1-year survival rates of patients with normal (≤ 135 U/L) and abnormal (> 135 U/L) serum ALP before treatment were 91% and 79%, respectively; the 2-year survival rates were 90% and 68%, respectively; and the 5-year survival rates were 35% and 18%, respectively. The difference between the two groups was statistically significant (P = 0.01). Before treatment, the 1-year survival rates of patients with normal serum GGT levels (≤ 45 U/L) and abnormal serum GGT levels (> 45 U/L) were 95% and 87%, the 2-year survival rates were 85% and 71%, and the 5-year survival rates were 37% and 21%, respectively. The difference between the two groups was statistically significant (P < 0.001). Serum ALP [hazard ratio (HR) = 1.766, 95% confidence interval (95%CI): 1.068-2.921, P = 0.027] and GGT (HR = 2. 312, 95%CI: 1.367-3.912, P = 0.002) is closely related to the overall survival of PLC patients after RF ablation and is an independent prognostic factor. The 1-year PFS rates were 72% and 50%, the 2-year PFS rates were 52% and 21%, and the 5-year PFS rates were 14% and 3%, respectively. The difference between the two groups was statistically significant (P < 0001). The 1-year PFS rates were 81% and 56% in patients with normal and abnormal serum GGT levels before treatment, respectively; the 2-year PFS rates were 62% and 35%, respectively; and the 5-year PFS rates were 18% and 7%, respectively, with statistical significance between the two groups (P < 0.001). The serum ALP concentration (HR = 1. 653, 95%CI: 1.001-2.729, P = 0.049) and GGT (HR = 1.949, 95%CI: 1.296-2.930, P = 0.001) was closely associated with PFS after RFA in patients with PLC. The proportion of male patients with abnormal ALP levels is high, the Child-Pugh grade of liver function is poor, and the incidence of ascites is high. Among GGT-abnormal patients, the Child-Pugh grade of liver function was poor, the tumor stage was late, the proportion of patients with tumors ≥ 5 cm was high, and the incidence of hepatic encephalopathy was high.

CONCLUSION

Serum ALP and GGT levels before treatment can be used to predict the prognosis of patients with PLC after RFA, and they have certain guiding significance for the long-term survival of patients with PLC after radiofrequency therapy.

Efficacy and safety of B-ultrasound-guided radiofrequency ablation in the treatment of primary liver cancer: Systematic review and meta-analysis

BACKGROUND

Primary liver cancer is one of the most lethal malignancies in the world. Traditional treatment methods have limitations in terms of efficacy and safety. Radiofrequency ablation (RFA) guided by B-ultrasound, as a minimally invasive treatment, has attracted increasing attention in the treatment of primary liver cancer in recent years.

AIM

To study the efficacy and safety of RFA were compared with those of traditional surgery (TS) for treating small liver cancer.

METHODS

At least 2 people were required to search domestic and foreign public databases, including foreign databases such as EMBASE, PubMed and the Cochrane Library, and Chinese databases such as the China National Knowledge Infrastructure database, China Biomedical Literature database, Wanfang database and VIP database. Controlled trials of RFA vs conventional surgery for small liver cancer were retrieved from January 2008 to January 2023. They were screened and evaluated according to the quality evaluation criteria in the Cochrane Handbook of Systematic Reviews. The meta-analysis was performed using RevMan 5.3 software.

RESULTS

A total of 10 studies were included in this study, including 1503 patients in the RFA group and 1657 patients in the surgery group. The results of the meta-analysis showed that there was no significant difference in 1-year overall survival between the two groups (P > 0.05), while the 3-year and 5-year overall survival rates and 1-year, 3-year and 5-year tumor-free survival rates in the surgery group were greater than those in the RFA group (P < 0.05). In terms of complications, the incidence of complications in the RFA group was lower than that in the surgery group (P < 0.05).

CONCLUSION

In terms of long-term survival, TS is better than RFA for small liver cancer patients. However, RFA has fewer complications and is safer.

The significance of countable and treatable metastatic liver disease in patients with gallbladder carcinoma after curative-intent surgery: A 10-year experience in China

OBJECTIVE

Our study was performed to evaluate the significance of countable and treatable metastatic liver disease (CTMLD) in patients with gallbladder carcinoma (GBC) after curative-intent surgery.

METHODS

Resected GBC patients between September 2010 and January 2021 were reviewed. Comparative analyses between patients with CTMLD and those without it were performed. A propensity score matching analysis was conducted for further validation.

RESULTS

A total of 326 resected GBC patients were identified (33 with CTMLD). A significantly higher preoperative CA199 level was detected in those with CTMLD (p = 0.0160). Significantly higher incidences of major hepatectomy (p = 0.0010), lymph node metastasis (p < 0.0001), direct liver invasion (p < 0.0001), moderate to poor differentiation status (p < 0.0001), and T3-4 disease (p < 0.0001) were detected in patients with CTMLD. Even sharing comparable surgical margin status, patients with CTMLD still shared a significantly higher recurrence rate (93.9% vs. 57.3%, p < 0.0001) as well as a significantly higher recurrence rate within 6 months after surgery (63.6% vs. 14.7%, p < 0.0001). A significantly worse overall survival (median survival time: 12 vs. 33 months, p < 0.0001) or disease-free survival (median recurrence-free time: 6 vs. 30 months, p < 0.0001) was acquired in patients with CTMLD. After matching, a significantly higher early recurrence rate was still detected. Adjuvant chemotherapy seemed to have survival benefit for patients with CTMLD.

CONCLUSION

CTMLD was an indicator of advanced disease and served as an independent predictor of early recurrence among resected GBC patients. Whether curative-intent surgery is superior to nonsurgical treatment among GBC patients with CTMLD remains to be explored in future prospective studies.

Image-Guided Ablation Therapies for Extrahepatic Metastases from Hepatocellular Carcinoma: A Review

The most common sites of extrahepatic metastases from hepatocellular carcinoma (HCC) are the lungs, intra-abdominal lymph nodes, bones, and adrenal glands, in that order. Although systemic therapies are a common treatment for patients with extrahepatic metastases, local ablative therapies for the extrahepatic metastatic lesions can be performed in selected patients. In this article, the literature on image-guided thermal ablation for metastasis to each organ was reviewed to summarize the current evidence. Radiofrequency ablation was the most commonly evaluated technique, and microwave ablation, cryoablation, and percutaneous ethanol injection were also utilized. The local control rate of thermal ablation therapy was relatively favorable, at approximately 70-90% in various organs. The survival outcomes varied among the studies, and several studies reported that the absence of viable intrahepatic lesions was associated with improved survival rates. Since only retrospective data from relatively small studies has been available thus far, more robust studies with prospective designs and larger cohorts are desired to prove the usefulness of thermal ablation for extrahepatic metastases from HCC.

The application of radiofrequency ablation in pancreatic cancer liver-only recurrence after radical pancreatectomy

To evaluate the safety, feasibility, and survival benefit of radiofrequency ablation in liver-only recurrence pancreatic cancer patients after radical pancreatectomy. The data and follow-up of pancreatic cancer patients who suffered liver-only recurrence after radical pancreatectomy from 2015 to 2021 were retrospectively collected. Finally, 19 liver metastases radiofrequency ablation patients were assigned to radiofrequency ablation group, and 41 patients were to systemic treatment group. (1) the baseline, perioperative characteristics, and pathological outcomes were well-balanced. (2) Recurrence pattern showed there were more multiple (> 3) recurrence tumors in systemic treatment patients (multiple one vs. 19, P = 0.005). (3) Median radiofrequency ablation operation time was 30.0 min, median blood loss was 1.0 ml, 4 (21.05%) patients suffered postoperative complications, and 94.74% liver metastases tumors got complete necrosis. The first efficacy evaluation showed a significantly better effect of radiofrequency ablation, complete and partial response rate 72.22% vs. 27.78%, P < 0.001. Overall survival from the initial surgery and after liver recurrence was significantly longer in the radiofrequency ablation group (43.0 vs. 22.0 months, 29.0 vs. 14.0 months, P = 0.003, 0.006, respectively). Progression-free survival after treatment was longer in the radiofrequency ablation group (6.0 vs. 5.0 months, P = 0.029). For liver recurrence tumor ≤ 3, overall survival from the initial surgery and after liver recurrence was significantly longer in radiofrequency ablation patients (43.0 vs. 22.0 months, 29.0 vs. 14.0 months, P = 0.011, 0.013, respectively). Progression-free survival after treatment was longer in the radiofrequency ablation group (7.0 vs. 4.0 months, P = 0.042). Radiofrequency ablation could get a curative purpose for patients with liver-only recurrence after pancreatectomy, improve progression-free survival and overall survival, and with minor surgery damage and risk.

Clinical applications of artificial intelligence in liver imaging

This review outlines the current status and challenges of the clinical applications of artificial intelligence in liver imaging using computed tomography or magnetic resonance imaging based on a topic analysis of PubMed search results using latent Dirichlet allocation. LDA revealed that "segmentation," "hepatocellular carcinoma and radiomics," "metastasis," "fibrosis," and "reconstruction" were current main topic keywords. Automatic liver segmentation technology using deep learning is beginning to assume new clinical significance as part of whole-body composition analysis. It has also been applied to the screening of large populations and the acquisition of training data for machine learning models and has resulted in the development of imaging biomarkers that have a significant impact on important clinical issues, such as the estimation of liver fibrosis, recurrence, and prognosis of malignant tumors. Deep learning reconstruction is expanding as a new technological clinical application of artificial intelligence and has shown results in reducing contrast and radiation doses. However, there is much missing evidence, such as external validation of machine learning models and the evaluation of the diagnostic performance of specific diseases using deep learning reconstruction, suggesting that the clinical application of these technologies is still in development.

Radiofrequency ablation for the management of pancreatic mass lesions

PURPOSE OF REVIEW

Patients with pancreatic tumors may have limited treatment options. Pancreatic tumor ablation is a novel and emerging treatment modality which can now be performed using endoscopic ultrasound (EUS) guidance. This modality is well suited to guide energy delivery for radiofrequency ablation (RFA) and microwave ablation. These approaches provide minimally invasive, nonsurgical methods for delivering energy to ablate pancreatic tumors in situ. This review summarizes the current data and safety profile for ablation in managing pancreatic cancer and pancreatic neuroendocrine tumors.

RECENT FINDINGS

RFA uses thermal energy to induce cell death by coagulative necrosis and protein denaturation. Studies have reported increased overall survival in patients with pancreatic tumors treated with EUS-guided RFA in a multimodality systemic approach and when used in palliative surgeries. Radiofrequency ablation may have corollary benefits in inducing an immune-modulatory effect. Tumor marker carbohydrate antigen 19-9 has been reported to decrease in response to RFA. Microwave ablation is an emerging modality.

SUMMARY

RFA utilizes focal thermal energy to induce cell death. RFA has been applied through open, laparoscopic, and radiographic modalities. EUS-guided approaches are now allowing RFA and microwave ablation to be performed for pancreatic tumors in situ.

Focal Cryo-Immunotherapy with Intratumoral IL-12 Prevents Recurrence of Large Murine Tumors

Focal ablation technologies are routinely used in the clinical management of inoperable solid tumors but they often result in incomplete ablations leading to high recurrence rates. Adjuvant therapies, capable of safely eliminating residual tumor cells, are therefore of great clinical interest. Interleukin-12 (IL-12) is a potent antitumor cytokine that can be localized intratumorally through coformulation with viscous biopolymers, including chitosan (CS) solutions. The objective of this research was to determine if localized immunotherapy with a CS/IL-12 formulation could prevent tumor recurrence after cryoablation (CA). Tumor recurrence and overall survival rates were assessed. Systemic immunity was evaluated in spontaneously metastatic and bilateral tumor models. Temporal bulk RNA sequencing was performed on tumor and draining lymph node (dLN) samples. In multiple murine tumor models, the addition of CS/IL-12 to CA reduced recurrence rates by 30-55%. Altogether, this cryo-immunotherapy induced complete durable regression of large tumors in 80-100% of treated animals. Additionally, CS/IL-12 prevented lung metastases when delivered as a neoadjuvant to CA. However, CA plus CS/IL-12 had minimal antitumor activity against established, untreated abscopal tumors. Adjuvant anti-PD-1 therapy delayed the growth of abscopal tumors. Transcriptome analyses revealed early immunological changes in the dLN, followed by a significant increase in gene expression associated with immune suppression and regulation. Cryo-immunotherapy with localized CS/IL-12 reduces recurrences and enhances the elimination of large primary tumors. This focal combination therapy also induces significant but limited systemic antitumor immunity.

Uncooled TATO microwave system for liver ablation

Aim: To evaluate the safety and efficacy of uncooled TATO microwave ablation (MWA) for primary and metastatic liver cancer. Materials & methods: This was a retrospective study on percutaneous liver ablations performed with TATO MWA. Twenty-five ablations were performed; 11 (44%) were performed for hepatocellular carcinoma, 14 (56%) for colorectal carcinoma, gastric and pancreatic metastases. Results: Adverse events were reported only in one (4%) ablation: an abscess that was observed in the ablated area and was resolved with a percutaneous drainage and antibiotic therapy. Local tumor control rate was 92% at the 3-month follow-up. Conclusion: TATO MWA was safe and effective with high reproducibility in treating primary and secondary liver cancer with satisfactory technical and clinical outcomes.