Complications after Thermal Ablation of Hepatocellular Carcinoma and Liver Metastases: Imaging Findings

Outcomes and Complications of Image-Guided Percutaneous Tumour Ablation for Hepatocellular Carcinoma at the Irish National Liver Transplant Centre

Background: Image-guided tumour ablation is a minimally invasive treatment for early stage hepatocellular carcinoma (HCC). Our study reviews the complications and long term outcomes in patients treated at a tertiary referral centre. Methods: Retrospective study. All patients with HCC who underwent microwave ablation (MWA) or radiofrequency ablation (RFA) from 1st January 2014 to 31st December 2022 were identified. Treatment response of target lesion, complications, and survival were recorded. Results: One hundred seventy ablations were performed in 118 patients; 70% MWA, 30% RFA. Median radiological follow-up 21 months (range 3-107). Follow-up imaging was reported using LI-RADS and mRECIST. At first follow-up imaging, 94 patients had complete response (primary efficacy rate 80.3%) while 19.7% (n = 23) had residual disease. Fifteen of these had repeat ablation; 10 had complete response (secondary efficacy rate 85.6%). By end of study duration, 70.5% (n = 79) achieved sustained local complete response from single ablation without documented recurrence. 14.3% (n = 16) required more than one ablation of target lesion. Overall, 84.8% (n = 95) demonstrated long term local complete response to ablation. Complication occurred in 5.9% (n = 10); 40.0% Grade I, 40.0% Grade II, 10.0% Grade III, 10.0% Grade IV as per the CIRSE Classification. 1-, 3-, and 5-year overall survival (OS) rate was 97%, 68%, and 61% respectively. Mean OS was 5.3 years (median 4.7). No difference in OS (P = .7) or local progression free survival (P = .5) between patients treated with MWA versus RFA. Conclusion: This study demonstrates excellent long-term response to TA, with acceptable complication profile. No difference in survival between RFA versus MWA.

Hepatobiliary phase MRI-guided radiofrequency ablation of small hepatocellular carcinomas invisible on precontrast MRI

PURPOSE

In cirrhotic livers reliable visualization and exact localization of small hepatocellular carcinoma (HCC) can be challenging without adequate contrast enhancement. To investigate the feasibility, technical success rate, and safety of hepatobiliary phase MRI-guided percutaneous radiofrequency ablation (RFA) of small HCCs invisible on precontrast MRI.

METHODS

53 patients (17f, 63.6 ± 16.7 years), with small HCC that were not visible in non-contrast MRI underwent MRI guided RFA. Feasibility was assessed by analyzing proper identification of the target tumor, tumor delineation during MRI-guided needle positioning and number of needle adjustments required for accurate placement. Technical success was defined as complete ablation with a safety margin of 5 mm. Safety was assessed from reports of procedure-related complications.

RESULTS

In all 53 cases, target tumors were not visible in non-contrast MRI but in the hepatobiliary phase. In 5 cases, planning imaging showed new tumors, which were either treated in the same session (n = 4) or altered the therapeutic approach (n = 1). Mean tumor diameter was 9.7 ± 1.9 mm and the number of needle adjustments was 5 ± 3. Post-ablation imaging showed a technical success rate of 98 % (51 cases, 55 tumors). No major complications occurred. Follow-up imaging (26.2 ± 22.4 month) showed no local tumor progression or recurrence.

CONCLUSIONS

Use of the hepatobiliary phase for MRI-guided ablation of otherwise MR-occult tumors is a feasible approach for an effective and safe treatment of small HCC nodules.

Efficacy of microwave ablation vs laparoscopic hepatectomy for primary small liver cancer: A comparative study

BACKGROUND

In-depth comparative investigations in terms of clinical efficacies of liver tumor microwave ablation (MWA) and laparoscopic hepatectomy (LH), which are both important treatment modalities for liver neoplasms, have been limited in patients diagnosed with primary small liver cancer (PSLC).

AIM

To compare and analyze the clinical efficacy of liver tumor MWA and LH for PSLC.

METHODS

This study retrospectively analyzed the medical records of 123 patients with PSLC admitted to Xuzhou Central Hospital from January 2015 to November 2022 and categorized them based on treatment modalities into the LH and MWA groups. The LH group, consisting of 61 cases, received LH, and the MWA group, which included 62 cases, underwent liver tumor MWA. Basic data and various perioperative indicators were compared between the two groups, including changes in liver function indicators [alanine aminotransferase (ALT), glutamic aminotransferase (AST), and total bilirubin (TBIL)] pre- and post-treatment, and efficacy and postoperative complications were analyzed.

RESULTS

No statistically significant difference was observed between the two groups in terms of age, gender, tumor diameter, liver function Child-Pugh classification and number of tumors, body mass index, and educational status (P > 0.05). The overall effective rate was higher in the MWA group than in the LH group (98.39% vs 88.52%) (χ 2 = 4.918, P = 0.027). The MWA group exhibited less operation time, intraoperative bleeding, defecation time, and hospital stay than the LH group (P < 0.05). No difference was found in liver function indicators between the two groups pre-treatment (P > 0.05), and ALT, AST, and TBIL levels decreased in both groups post-treatment, with the MWA group demonstrating lower levels (P < 0.05). The MWA and LH groups exhibited postoperative complication rates of 4.84% and 19.67%, respectively, with statistically significant differences between the two groups (P = 0.012, χ 2 = 6.318).

CONCLUSION

MWA is more effective in treating PSLC, and it promotes faster postoperative recovery for patients, and more security improves liver function and reduces postoperative complications compared to LH.

Histotripsy of Liver Tumors: Patient Selection, Ethical Discussions, and How We Do It

Liver malignancies, both primary and metastatic tumors, are a major cause of cancer-related mortality. Colorectal cancer alone results in liver metastases in nearly 50% of patients, with approximately 85% presenting with unresectable disease. Similarly, hepatocellular carcinoma and intrahepatic cholangiocarcinoma frequently present at advanced stages, limiting curative options. Systemic therapies provide modest survival benefits, underscoring the need for alternative treatments. Locoregional approaches, such as thermal ablation and chemoembolization, while effective, have notable limitations, including invasiveness, peri-procedural risks, and the requirement to interrupt systemic treatments. Histotripsy is a novel, non-invasive method that uses focused ultrasound-induced cavitation to enable precise tumor ablation without heat or radiation. Our institution utilizes a multidisciplinary tumor board approach to evaluate patients for histotripsy, particularly in cases involving unresectable disease, complex surgical candidacy, palliative intent related to disease control and symptom management, or as bridging therapy for transplantation. Early results, including preclinical data and the THERESA and #HOPE4LIVER trials, highlight its efficacy in treating liver tumors with minimal complications. This review outlines institutional protocols for histotripsy, covering pre- and post-procedural management, along with ethical considerations of current treatment paradigms. As a patient-centered approach, histotripsy offers a novel treatment option with a favorable safety profile and compatibility with systemic therapies.

What Is the Optimal Locoregional Approach for Recurrent Hepatocellular Carcinoma?

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

Locoregional Therapies for Hepatocellular Carcinoma in Patients with Nonalcoholic Fatty Liver Disease

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death worldwide with an average five-year survival rate in the US of 19.6%. With the advent of HBV and HCV treatment and prevention, along with the rising rates of obesity, nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome are set to overtake infectious causes as the most common cause of HCC. While surgical resection and transplantation can be curative when amenable, the disease is most commonly unresectable on presentation, and other treatment approaches are the mainstay of therapy. In these patients, locoregional therapies have evolved as a vital tool in both palliation for advanced disease and as a bridge to surgical resection and transplantation. In this review, we will be exploring the primary locoregional therapies for HCC in patients with NAFLD, including transarterial chemoembolization (TACE), bland transarterial embolization (TAE), transarterial radioembolization (TARE), and percutaneous ablation.

Examining the Efficacy and Safety of Combined Locoregional Therapy and Immunotherapy in Treating Hepatocellular Carcinoma

More than 800,000 people worldwide are diagnosed with HCC (hepatocellular carcinoma) each year, with approximately 700,000 deaths alone occurring in that same year. Treatment of HCC presents complex therapeutic challenges, particularly in intermediate and advanced stages. LRTs such as transarterial chemoembolization (TACE) and ablations have been the mainstay treatment for early to intermediate-stage HCC, and systemic therapies are used to treat intermediate-late-stage HCC. However, novel literature describing combining LRT with systemic therapies has shown promising results. This review explores recent advances in both liver-directed techniques for hepatocellular carcinoma, including bland transarterial embolization, chemoembolization, radioembolization, and ablative therapies in conjunction as well as with systemic therapies, with a focus on combination therapies, patient selection, procedural technique, periprocedural management, and outcomes. Our findings suggest that LRT combined with systemic therapies is a viable strategy for improving progression-free survival and time to progression for patients with intermediate-to-late-stage HCC. However, further investigation is required to refine treatment protocols and define patient cohorts that would benefit the most.

Development and preclinical evaluation of multifunctional hydrogel for precise thermal protection during thermal ablation

Image-guided thermal ablation (TA), which is less invasive, has been widely applied for treating various kinds of tumors. However, TA still poses the potential risk of thermal damage to sensitive tissue nearby. Therefore, an adjunctive thermoprotective hydrodissection technique with constant injection of 5% glucose (5% Glu) has currently been adopted for clinical application, but this may be hazardous to humans. In this study, a multifunctional hyaluronic acid-based hydrogel (HA-Dc) was developed for hydrodissection. Compared with 5% Glu (the most clinically used solution) and the previously reported F127 hydrogel, the HA-Dc hydrogel was studied in vitro in a porcine liver model and in vivo in a rabbit model and showed good injectability and better tissue retention, stability, and thermoprotective properties throughout the TA procedure. Furthermore, in the preclinical evaluation in a Macaca fascicularis (M. fascicularis) model, HA-Dc showed excellent performance in terms of stricter neuroprotection compared with 5% Glu. In addition, the HA-Dc hydrogel with good biocompatibility and controllable degradation behavior in vivo could be a promising platform for thermal protection during clinical TA procedures.

Radiomics and machine learning analysis by computed tomography and magnetic resonance imaging in colorectal liver metastases prognostic assessment

OBJECTIVE

The aim of this study was the evaluation radiomics analysis efficacy performed using computed tomography (CT) and magnetic resonance imaging in the prediction of colorectal liver metastases patterns linked to patient prognosis: tumor growth front; grade; tumor budding; mucinous type. Moreover, the prediction of liver recurrence was also evaluated.

METHODS

The retrospective study included an internal and validation dataset; the first was composed by 119 liver metastases from 49 patients while the second consisted to 28 patients with single lesion. Radiomic features were extracted using PyRadiomics. Univariate and multivariate approaches including machine learning algorithms were employed.

RESULTS

The best predictor to identify tumor growth was the Wavelet_HLH_glcm_MaximumProbability with an accuracy of 84% and to detect recurrence the best predictor was wavelet_HLH_ngtdm_Complexity with an accuracy of 90%, both extracted by T1-weigthed arterial phase sequence. The best predictor to detect tumor budding was the wavelet_LLH_glcm_Imc1 with an accuracy of 88% and to identify mucinous type was wavelet_LLH_glcm_JointEntropy with an accuracy of 92%, both calculated on T2-weigthed sequence. An increase statistically significant of accuracy (90%) was obtained using a linear weighted combination of 15 predictors extracted by T2-weigthed images to detect tumor front growth. An increase statistically significant of accuracy at 93% was obtained using a linear weighted combination of 11 predictors by the T1-weigthed arterial phase sequence to classify tumor budding. An increase statistically significant of accuracy at 97% was obtained using a linear weighted combination of 16 predictors extracted on CT to detect recurrence. An increase statistically significant of accuracy was obtained in the tumor budding identification considering a K-nearest neighbors and the 11 significant features extracted T1-weigthed arterial phase sequence.

CONCLUSIONS

The results confirmed the Radiomics capacity to recognize clinical and histopathological prognostic features that should influence the choice of treatments in colorectal liver metastases patients to obtain a more personalized therapy.

Colorectal liver metastases patients prognostic assessment: prospects and limits of radiomics and radiogenomics

In this narrative review, we reported un up-to-date on the role of radiomics to assess prognostic features, which can impact on the liver metastases patient treatment choice. In the liver metastases patients, the possibility to assess mutational status (RAS or MSI), the tumor growth pattern and the histological subtype (NOS or mucinous) allows a better treatment selection to avoid unnecessary therapies. However, today, the detection of these features require an invasive approach. Recently, radiomics analysis application has improved rapidly, with a consequent growing interest in the oncological field. Radiomics analysis allows the textural characteristics assessment, which are correlated to biological data. This approach is captivating since it should allow to extract biological data from the radiological images, without invasive approach, so that to reduce costs and time, avoiding any risk for the patients. Several studies showed the ability of Radiomics to identify mutational status, tumor growth pattern and histological type in colorectal liver metastases. Although, radiomics analysis in a non-invasive and repeatable way, however features as the poor standardization and generalization of clinical studies results limit the translation of this analysis into clinical practice. Clear limits are data-quality control, reproducibility, repeatability, generalizability of results, and issues related to model overfitting.

Radiation Recall Pneumonitis: The Open Challenge in Differential Diagnosis of Pneumonia Induced by Oncological Treatments

The treatment of primary and secondary lung neoplasms now sees the fundamental role of radiotherapy, associated with surgery and systemic therapies. The improvement in survival outcomes has also increased attention to the quality of life, treatment compliance and the management of side effects. The role of imaging is not only limited to recognizing the efficacy of treatment but also to identifying, as soon as possible, the uncommon effects, especially when more treatments, such as chemotherapy, immunotherapy and radiotherapy, are associated. Radiation recall pneumonitis is an uncommon treatment complication that should be correctly characterized, and it is essential to recognize the mechanisms of radiation recall pneumonitis pathogenesis and diagnostic features in order to promptly identify them and adopt the best therapeutic strategy, with the shortest possible withdrawal of the current oncological drug. In this setting, artificial intelligence could have a critical role, although a larger patient data set is required.

Risk Assessment and Cholangiocarcinoma: Diagnostic Management and Artificial Intelligence

Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver tumor, with a median survival of only 13 months. Surgical resection remains the only curative therapy; however, at first detection, only one-third of patients are at an early enough stage for this approach to be effective, thus rendering early diagnosis as an efficient approach to improving survival. Therefore, the identification of higher-risk patients, whose risk is correlated with genetic and pre-cancerous conditions, and the employment of non-invasive-screening modalities would be appropriate. For several at-risk patients, such as those suffering from primary sclerosing cholangitis or fibropolycystic liver disease, the use of periodic (6-12 months) imaging of the liver by ultrasound (US), magnetic Resonance Imaging (MRI)/cholangiopancreatography (MRCP), or computed tomography (CT) in association with serum CA19-9 measurement has been proposed. For liver cirrhosis patients, it has been proposed that at-risk iCCA patients are monitored in a similar fashion to at-risk HCC patients. The possibility of using Artificial Intelligence models to evaluate higher-risk patients could favor the diagnosis of these entities, although more data are needed to support the practical utility of these applications in the field of screening. For these reasons, it would be appropriate to develop screening programs in the research protocols setting. In fact, the success of these programs reauires patient compliance and multidisciplinary cooperation.

Imaging Features of Main Hepatic Resections: The Radiologist Challenging

Liver resection is still the most effective treatment of primary liver malignancies, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), and of metastatic disease, such as colorectal liver metastases. The type of liver resection (anatomic versus non anatomic resection) depends on different features, mainly on the type of malignancy (primary liver neoplasm versus metastatic lesion), size of tumor, its relation with blood and biliary vessels, and the volume of future liver remnant (FLT). Imaging plays a critical role in postoperative assessment, offering the possibility to recognize normal postoperative findings and potential complications. Ultrasonography (US) is the first-line diagnostic tool to use in post-surgical phase. However, computed tomography (CT), due to its comprehensive assessment, allows for a more accurate evaluation and more normal findings than the possible postoperative complications. Magnetic resonance imaging (MRI) with cholangiopancreatography (MRCP) and/or hepatospecific contrast agents remains the best tool for bile duct injuries diagnosis and for ischemic cholangitis evaluation. Consequently, radiologists should be familiar with the surgical approaches for a better comprehension of normal postoperative findings and of postoperative complications.

Risk Assessment and Pancreatic Cancer: Diagnostic Management and Artificial Intelligence

Pancreatic cancer (PC) is one of the deadliest cancers, and it is responsible for a number of deaths almost equal to its incidence. The high mortality rate is correlated with several explanations; the main one is the late disease stage at which the majority of patients are diagnosed. Since surgical resection has been recognised as the only curative treatment, a PC diagnosis at the initial stage is believed the main tool to improve survival. Therefore, patient stratification according to familial and genetic risk and the creation of screening protocol by using minimally invasive diagnostic tools would be appropriate. Pancreatic cystic neoplasms (PCNs) are subsets of lesions which deserve special management to avoid overtreatment. The current PC screening programs are based on the annual employment of magnetic resonance imaging with cholangiopancreatography sequences (MR/MRCP) and/or endoscopic ultrasonography (EUS). For patients unfit for MRI, computed tomography (CT) could be proposed, although CT results in lower detection rates, compared to MRI, for small lesions. The actual major limit is the incapacity to detect and characterize the pancreatic intraepithelial neoplasia (PanIN) by EUS and MR/MRCP. The possibility of utilizing artificial intelligence models to evaluate higher-risk patients could favour the diagnosis of these entities, although more data are needed to support the real utility of these applications in the field of screening. For these motives, it would be appropriate to realize screening programs in research settings.

A Narrative Review on LI-RADS Algorithm in Liver Tumors: Prospects and Pitfalls

Liver cancer is the sixth most detected tumor and the third leading cause of tumor death worldwide. Hepatocellular carcinoma (HCC) is the most common primary liver malignancy with specific risk factors and a targeted population. Imaging plays a major role in the management of HCC from screening to post-therapy follow-up. In order to optimize the diagnostic-therapeutic management and using a universal report, which allows more effective communication among the multidisciplinary team, several classification systems have been proposed over time, and LI-RADS is the most utilized. Currently, LI-RADS comprises four algorithms addressing screening and surveillance, diagnosis on computed tomography (CT)/magnetic resonance imaging (MRI), diagnosis on contrast-enhanced ultrasound (CEUS) and treatment response on CT/MRI. The algorithm allows guiding the radiologist through a stepwise process of assigning a category to a liver observation, recognizing both major and ancillary features. This process allows for characterizing liver lesions and assessing treatment. In this review, we highlighted both major and ancillary features that could define HCC. The distinctive dynamic vascular pattern of arterial hyperenhancement followed by washout in the portal-venous phase is the key hallmark of HCC, with a specificity value close to 100%. However, the sensitivity value of these combined criteria is inadequate. Recent evidence has proven that liver-specific contrast could be an important tool not only in increasing sensitivity but also in diagnosis as a major criterion. Although LI-RADS emerges as an essential instrument to support the management of liver tumors, still many improvements are needed to overcome the current limitations. In particular, features that may clearly distinguish HCC from cholangiocarcinoma (CCA) and combined HCC-CCA lesions and the assessment after locoregional radiation-based therapy are still fields of research.

Imaging Assessment of Interval Metastasis from Melanoma

Interval metastasis is a particular metastatic category of metastatic localizations in the lymph nodes in patients with melanoma. Interval nodes are generally located at nonregional lymphatic stations placed along the pathway of the spread of melanoma, such as the epitrochlear lymph node station, the popliteal fossa, and the retroareolar station. Imaging techniques for evaluation of patients with interval metastasis from melanoma diseases include ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI), lymphoscintigraphy (LS), and positron emission tomography (PET). A literature review was conducted through a methodical search on the Pubmed and Embase databases. The evaluation of lymph node metastases represents a critical phase in the staging and follow-up of melanoma patients. Therefore, a thorough knowledge of the imaging methods available and the interactions between the clinician and the radiologist are essential for making the correct choice for individual patients, for a better management, and to improve treatment and survival.