Long-term outcomes of percutaneous cryoablation for patients with hepatocellular carcinoma within Milan criteria

Localized Photodynamic Therapy Using a Chlorin e6-Embedded Silicone-Covered Self-Expandable Metallic Stent as a Palliative Treatment for Malignant Esophageal Strictures

Localized photodynamic therapy (PDT) uses a polymeric-photosensitizer (PS)-embedded, covered self-expandable metallic stent (SEMS). PDT is minimally invasive and a noteworthy potential alternative for treating esophageal strictures, where surgery is not a viable option. However, preclinical evidence is insufficient, and optimized irradiation energy dose ranges for localized PDT are unclear. Herein, we validated the irradiation energy doses of the SEMS (embedded in a PS using chlorin e6 [Ce6] and covered in silicone) and PDT-induced tissue changes in a rat esophagus. Cytotoxicity and phototoxicity in the Ce6-embedded SEMS piece with laser irradiation were significantly higher than that of the silicone-covered SEMS with or without laser and the Ce6-embedded silicone-covered SEMS without laser groups (all p < 0.001). Moreover, surface morphology, atomic changes, and homogeneous coverage of the Ce6-embedded silicone-covered membrane were confirmed. The ablation range of the porcine liver was proportionally increased with the irradiation dose (all p < 0.001). The ablation region was identified at different irradiation energy doses of 50, 100, 200, and 400 J/cm2. The in vivo study in the rat esophagus comprised a control group and 100, 200, and 400 J/cm2 energy-dose groups. Finally, histology and immunohistochemistry (TUNEL and Ki67) confirmed that the optimized Ce6-embedded silicone-covered SEMS with selected irradiation energy doses (200 and 400 J/cm2) effectively damaged the esophageal tissue without ductal perforation. The polymeric PS-embedded silicone-covered SEMS can be easily placed via a minimally invasive approach and represents a promising new approach for the palliative treatment of malignant esophageal strictures.

Computed tomography-guided percutaneous cryoablation and microwave ablation in the treatment of perivascular hepatocellular carcinoma: A comparative study with propensity score matching

OBJECTIVE

To evaluate the safety and efficacy of cryoablation (CYA) and microwave ablation (MWA) in the treatment of patients with perivascular hepatocellular carcinoma (HCC).

METHODS

Patients with perivascular HCC who underwent computed tomography (CT)-guided percutaneous CYA or MVA treatment in our hospital from August 2009 to March 2019 were included. Propensity score matching (PSM) was performed to adjust for potential baseline differences in the two groups. The technical success rate (TS), complications, and visual analog scale (VAS) were analyzed. The overall survival (OS) was evaluated using Kaplan-Meier curves and Cox proportional hazards models.

RESULTS

After PSM, 32 patients from each group were selected. The technical success rate was 94 % for CYA and 91 % for MWA, and 13 patients developed recurrence (CYA, n = 5, 2 local, 3 distant; MWA, n = 8, 6 local, 2 distant). There were no significant differences in OS (36-months OS: CYA 53.1 % vs, MWA 40.6 %; P = 0.191). No intraoperative deaths or complication-related deaths were observed, and 19 patients (CYA, n = 8; MWA, n = 11) experienced complications (P = 0.435). The VAS in the MWA group (5.38 ± 1.21) was significantly higher than that in the CYA group (2.22 ± 0.87; P < 0.001).

CONCLUSIONS

While CYA has equal safety and high primary efficacy as MWA in the treatment of perivascular HCC, it is associated with less periprocedural pain.

Improved Thermal Sensitivity Using Virtual Monochromatic Imaging Derived from Photon Counting Detector CT Data Sets: Ex Vivo Results of CT-Guided Cryoablation in Porcine Liver

PURPOSE

To investigate differences in thermal sensitivity of virtual monoenergetic imaging (VMI) series generated from photon-counting detector (PCD) CT data sets, regarding their use to improve discrimination of the ablation zone during percutaneous cryoablation.

MATERIALS AND METHODS

CT-guided cryoablation was performed using an ex vivo model of porcine liver on a PCD-CT system. The ablation zone was imaged continuously for 8 min by acquiring a CT scan every 5 s. Tissue temperature was measured using fiberoptic temperature probes placed parallel to the cryoprobe. CT-values and noise were measured at the tip of the temperature probes on each scan and on VMI series from 40 to 130 keV. Correlation of CT-values and temperature was assessed using linear regression analyses.

RESULTS

For the whole temperature range of [- 40, + 20] °C, we observed a linear correlation between CT-values and temperature in reference 70 keV images (R2 = 0.60, p < 0.001) with a thermal sensitivity of 1.4HU/°C. For the most dynamic range of [- 15, + 20] °C, the sensitivity increased to 2.4HU/°C (R2 = 0.50, p < 0.001). Using VMI reconstructions, the thermal sensitivity increased from 1.4 HU/°C at 70 keV to 1.5, 1.7 and 2.0HU/°C at 60, 50 and 40 keV, respectively (range [- 40, + 20] °C). For [- 15, + 20]°C, the thermal sensitivity increased from 2.4HU/°C at 70 keV to 2.5, 2.6 and 2.7HU/°C at 60, 50 and 40 keV, respectively. Both CT-values and noise also increased with decreasing VMI keV-levels.

CONCLUSION

During CT-guided cryoablation of porcine liver, low-keV VMI reconstructions derived from PCD-CT data sets exhibit improved thermal sensitivity being highest between + 20 and - 15 °C.

Immune checkpoint inhibition: a future guided by radiology

The limitation of the function of antitumour immune cells is a common hallmark of cancers that enables their survival. As such, the potential of immune checkpoint inhibition (ICI) acts as a paradigm shift in the treatment of a range of cancers but has not yet been fully capitalised. Combining minimally and non-invasive locoregional therapies offered by radiologists with ICI is now an active field of research with the aim of furthering therapeutic capabilities in medical oncology. In parallel to this impending advancement, the "imaging toolbox" available to radiologists is also growing, enabling more refined tumour characterisation as well as greater accuracy in evaluating responses to therapy. Options range from metabolite labelling to cellular localisation to immune checkpoint screening. It is foreseeable that these novel imaging techniques will be integrated into personalised treatment algorithms. This growth in the field must include updating the current standardised imaging criteria to ensure they are fit for purpose. Such criteria is crucial to both appropriately guide clinical decision-making regarding next steps of treatment, but also provide reliable prognosis. Quantitative approaches to these novel imaging techniques are also already being investigated to further optimise personalised therapeutic decision-making. The therapeutic potential of specific ICIs and locoregional therapies could be determined before administration thus limiting unnecessary side-effects whilst maintaining efficacy. Several radiological aspects of oncological care are advancing simultaneously. Therefore, it is essential that each development is assessed for clinical use and optimised to ensure the best treatment decisions are being offered to the patient. In this review, we discuss state of the art advances in novel functional imaging techniques in the field of immuno-oncology both pre-clinically and clinically.

Role of Percutaneous Ablation in the Management of Intrahepatic Cholangiocarcinoma

Cholangiocarcinoma (CCA) is an invasive cancer accounting for <1% of all cancers and 10-15% of primary liver cancers. Intrahepatic CCA (iCCA) is associated with poor survival rates and high post-surgical recurrence rates whilst most diagnosed patients are not surgical candidates. There is a growing literature suggesting percutaneous ablative techniques for the management of patients with iCCA measuring ≤3 cm with contraindications to surgery as well as for recurrent or residual tumors aiming to provide local cancer treatment and control. Most used ablative therapies for iCCA include radiofrequency and microwave ablation with irreversible electroporation, cryoablation and reversible electroporation (electrochemotherapy) being less commonly encountered techniques. Due to the infiltrative margins of the lesion, there is a need for larger safety margins and ablation zone; multi-apparatus ablation or other variations of the technique such as balloon-assisted approaches can be utilized aiming to increase size of the zone of necrosis. The present review paper focuses upon the current role of percutaneous ablative techniques for the therapeutic management of iCCA. The purpose of this review is to present the current minimally invasive ablative techniques in the treatment of iCCA, including local control and survival rates.

Minimally Invasive Treatment Options for Hepatic Uveal Melanoma Metastases

Uveal melanoma is one of the most common primary intraocular malignancies that accounts for about 85% of all ocular melanomas. The pathophysiology of uveal melanoma is distinct from cutaneous melanoma and has separate tumor profiles. The management of uveal melanoma is largely dependent on the presence of metastases, which confers a poor prognosis with a one-year survival reaching only 15%. Although a better understanding of tumor biology has led to the development of novel pharmacologic agents, there is increasing demand for minimally invasive management of hepatic uveal melanoma metastases. Multiple studies have already summarized the systemic therapeutic options available for metastatic uveal melanoma. This review covers the current research for the most prevalent locoregional treatment options for metastatic uveal melanoma including percutaneous hepatic perfusion, immunoembolization, chemoembolization, thermal ablation, and radioembolization.

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.

Interventional Radiology in the Treatment of Pancreatic Adenocarcinoma: Present and Future Perspectives

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease; patients' long-term survival is strictly linked to the surgical resection of the tumor but only a minority of patients (2-3%) have a resectable disease at diagnosis. In patients with surgically unresectable disease, interventional radiology is taking on an increasing role in treatment with the application of loco-regional percutaneous therapies. The primary purposes of this narrative review are to analyze the safety and efficacy of ablative techniques in the management of borderline resectable and locally advanced diseases and to underline the role of the interventional radiologist in the management of patients with distant metastases. The secondary purpose is to focus on the synergy between immunotherapy and ablative therapies.

Imaging and Pathologic Evaluation of Cryoablation of Woodchuck (Marmota monax) Hepatocellular Carcinoma

We characterized cryoablation as a mode of clinical intervention in adult woodchucks with hepatocellular carcinoma (HCC). Woodchucks (n = 4) were infected with woodchuck hepatitis virus at birth and developed LI-RADS-5 hypervascular HCC. At 21 mo of age, they underwent ultrasound (US), contrast-enhanced CT (CECT) imaging, and US-guided subtotal cryoablation (IcePearl 2.1 CX, Galil, BTG) of their largest tumor (Mean HCC volume of 49 ± 9 cm³). Cryoablation was performed using two 10-min freeze cycles, each followed by an 8-min thaw cycle. The first woodchuck developed significant hemorrhage after the procedure and was euthanized. In the other 3 woodchucks, the probe track was cauterized and all 3 completed the study. Fourteen days after ablation, CECT was performed, and woodchucks were euthanized. Explanted tumors were sectioned using subject-specific, 3D-printed cutting molds. Initial tumor volume, the size of the cryoablation ice ball, gross pathology and hematoxylin and eosin-stained tissue sections were evaluated. On US, the edges of the solid ice balls were echogenic with dense acoustic shadowing and average dimensions of 3.1 ± 0.5 × 2.1 ± 0.4 cm and cross-sectional area of 4.7 ± 1.0 cm². On day 14 after cryoablation, CECT of the 3 woodchucks showed devascularized hypo-attenuating cryolesions with dimensions of 2.8 ± 0.3 × 2.6 ± 0.4 × 2.93 ± 0.7 cm and a cross sectional area of 5.8 ± 1.2 cm². Histopathologic evaluation showed hemorrhagic necrosis with a central amorphous region of coagulative necrosis surrounded by a rim of karyorrhectic debris. A rim of approximately 2.5 mm of coagulative necrosis and fibrous connective tissue clearly demarcated the cryolesion from adjacent HCC. Partial cryoablation of tumors produced coagulative necrosis with well-defined ablation margins at 14 d. Cauterization appeared to prevent hemorrhage after cryoablation of hypervascular tumors. Our findings indicate that woodchucks with HCC may provide a predictive preclinical model for investigating ablative modalities and developing new combination therapies.

Indian College of Radiology and Imaging Guidelines on Interventions in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies and a significant cause of cancer-related death. Treatment of HCC depends on the stage of the tumor. As many patients with HCC are not deemed fit for surgical resection or liver transplantation, locoregional therapies play an essential role in the management. Image-guided locoregional treatments include percutaneous ablative therapies and endovascular therapies. The choice of an individual or a combination of therapies is guided by the tumor and patient characteristics. As the outcomes of image-guided locoregional treatments depend on the ability to achieve necrosis of the entire tumor along with a safety margin around it, it is mandatory to follow standard guidelines. In this manuscript, we discuss in detail the various aspects of image-guided locoregional therapies to guide interventional radiologists involved in the care of patients with HCC.

Update on Percutaneous Local Ablative Procedures for the Treatment of Hepatocellular Carcinoma

BACKGROUND

 Hepatocellular carcinoma (HCC) is the fifth most common tumor worldwide. Because many hepatocellular carcinomas are already unresectable at the time of initial diagnosis, percutaneous tumor ablation has become established in recent decades as a curative therapeutic approach for very early (BCLC 0) and early (BCLC A) HCC. The aim of this paper is to provide a concise overview of the percutaneous local ablative procedures currently in use, based on their technical characteristics as well as clinical relevance, taking into account the current body of studies.

MATERIALS AND METHODS

 The literature search included all original papers, reviews, and meta-analyses available via MEDLINE and Pubmed on the respective percutaneous ablation procedures; the primary focus was on randomized controlled trials and publications from the last 10 years.

RESULTS AND CONCLUSIONS

 Radiofrequency ablation (RFA) and microwave ablation (MWA) are well-established procedures that are considered equal to surgical resection in the treatment of stage BCLC 0 and A HCC with a diameter up to 3 cm due to their strong evidence in international and national guidelines. For tumors with a diameter between 3 and 5 cm, the current S3 guidelines recommend a combination of transarterial chemoembolization (TACE) and thermal ablation using RFA or MWA as combination therapy is superior to thermal ablation alone in tumors of this size and shows comparable results to surgical resection in terms of overall survival. Alternative, less frequently employed thermal procedures include cryotherapy (CT) and laser ablation (LA). Non-thermal procedures include irreversible electroporation (IRE), interstitial brachytherapy (IBT), and most recently, electrochemotherapy (ECT). Due to insufficient evidence, these have only been used in individual cases and within the framework of studies. However, the nonthermal methods are a reasonable alternative for ablation of tumors adjacent to large blood vessels and bile ducts because they cause significantly less damage to these structures than thermal ablation methods. With advances in the technology of the respective procedures, increasingly good evidence, and advancements in supportive techniques such as navigation devices and fusion imaging, percutaneous ablation procedures may expand their indications for the treatment of larger and more advanced tumors in the coming years.

KEY POINTS

· RFA and MWA are considered equal to surgical resection as a first-line therapy for the curative treatment of stage BCLC 0 and A HCCs with a diameter of up to 3 cm.. · For HCCs with a diameter between 3 and 5 cm, a combination of TACE and RFA or MWA is recommended. This combination therapy yields results comparable to those of surgical resection in terms of overall survival.. · Due to insufficient evidence, alternative ablation methods have only been used in individual cases and within the framework of studies. However, nonthermal methods, such as IRE, IBT, and, most recently, ECT, are a reasonable alternative for ablation of HCCs adjacent to large blood vessels and bile ducts because they cause significantly less damage to these structures than thermal ablation methods..

CITATION FORMAT

· Luerken L, Haimerl M, Doppler M et al. Update on Percutaneous Local Ablative Procedures for the Treatment of Hepatocellular Carcinoma. Fortschr Röntgenstr 2022; DOI: 10.1055/a-1768-0954.

Efficacy and safety of percutaneous cryoablation for elderly patients with small hepatocellular carcinoma: A prospective multicenter study

BACKGROUND & AIMS

Management of elderly patients with hepatocellular carcinoma (HCC) has become a major concern. Some data suggest that cryoablation improves the outcomes of elderly patients with HCC, but its efficacy and safety remain unknown. This study aimed to evaluate and compare the efficacy and safety of percutaneous cryoablation with those of radiofrequency ablation (RFA) for elderly HCC patients.

METHODS

In all, 223 patients with small HCC aged ≥70 years, treatment-naïve, without metastasis were enrolled and randomized into a cryoablation group (n = 112) or a RFA (n = 111) group from July 2015 to October 2018. The primary endpoint was local tumour progression (LTP) at 3 years after treatment. The secondary endpoints including overall survival (OS), tumour-free survival (TFS), LTP and safety were analysed for these two groups after both treatments.

RESULTS

LTP rates at 1-, 3- and 5-year were 12%, 17% and 20% for cryoablation and 17%, 18% and 21% for RFA respectively (P = .735). For lesions >3 cm in diameter, LTP rates at 1- and 3-year were 13% and 22% in cryoablation group and 22% and 42% respectively, in the RFA group (P = .039). The 1-, 3- and 5-year OS rates were 90, 75% and 62% for cryoablation and 90%, 68% and 63% for RFA respectively (P = .331). The 1-, 3- and 5-year TFS rates were 59%, 32% and 25% in the cryoablation and 59%, 28% and 20% in the RFA respectively (P = .309). Major complications occurred in 6 patients (5%) following cryoablation and 6 patients (6%) following RFA (P = .886).

CONCLUSION

Cryoablation and RFA had similar LTP in elderly patients with small HCC and this study failed to meet the primary endpoint, although for a relatively large early-stage HCC the LTP rate after cryoablation was significantly lower than that after RFA.

Periprocedural factors associated with overall patient survival following percutaneous image-guided liver tumor cryoablation

PURPOSE

To assess the impact of periprocedural factors, including adverse events, on overall patient survival following image-guided liver tumor cryoablation procedures.

METHODS

In this retrospective single-institution study, 143 patients (73 male, 70 female, ages 29-88) underwent 169 image-guided liver tumor cryoablation procedures between October 1998 and August 2014. Patient, tumor and procedural variables were recorded. The primary outcome was overall survival post-procedure (Kaplan-Meier analysis). Secondary outcomes were the impact of 15 variables on patient survival, which were assessed with multivariate cox regression and log-rank tests.

RESULTS

Mean tumor diameter was 2.5 ± 1.2 cm. 26 of 143 (18.2%) patients had primary hepatic malignancies; 117 of 143 (81.8%) had liver metastases. Survival analysis revealed survivor functions at 3, 5, 7, 10 and 12 years post-ablation of 0.54, 0.37, 0.30, 0.17 and 0.06, with mean survival time of 40.8 ± 4.9 months. Tumor size ≥4 cm (p = .018), pre-procedural platelet count <100 × 10³/μL (p = .023), and prior local radiation therapy (p = .014) were associated with worse overall patient survival. Grade 3 or higher adverse events were not associated with reduced survival (p = .49).

CONCLUSIONS

All variables associated with overall survival were patient-related and none were associated with the cryoablation procedure. Pre-procedural thrombocytopenia, larger tumor size and history of prior local radiation therapy were independent risk factors for reduced overall survival in patients undergoing hepatic cryoablation. Adverse events related to hepatic cryoablation were not associated with decreased survival.

Cryoshock following cryoablation for hepatocellular carcinoma

We present a case of profound shock and lactic acidemia occurring in the context of a cryoablative procedure for hepatocellular carcinoma. After out ruling more common possible etiologies, we diagnosed our patient as having a rare cause of shock, unique to these types of cryoablative procedures, known as cryoshock. Cryoablation can result in multiple complications one of which is 'cryoshock', a life-threatening syndrome of multiorgan failure and coagulopathy that carries a high mortality, up to 40%. While the mechanism of cryoshock has not been completely elucidated, it appears to be mediated by the release of cytokines TNF-alpha, IL-1, and IL-6. It is causally associated with complete thaw prior to refreezing and double freeze cycles, as well as volume of and duration of cryotherapy. Cryoreaction, which is a milder phenomenon including chills fever, tachycardia, tachypnea and temporary renal damage has been described after 1% of cryoablation sessions. Reports of the management of cryoshock are scarce and the mainstay of treatment is organ support. While cryoshock has been described in radiology and surgical literature it has not previously been described in anesthesiology literature. We highlight this as a potential serious complication which should be considered by all clinicians involved in these cases.

Image-guided locoregional non-intravascular interventional treatments for hepatocellular carcinoma: Current status

Hepatocellular carcinoma (HCC) is one of the most deadly and frequent cancers worldwide, although great advancement in the treatment of this malignancy have been made within the past few decades. It continues to be a major health issue due to an increasing incidence and a poor prognosis. The majority of patients have their HCC diagnosed at an intermediate or advanced stage in theUSA or China. Curative therapy such as surgical resection or liver transplantation is not considered anoption of treatment at these stages.

Transarterial chemoembolization (TACE), the most widely used locoregional therapeutic approach, used to be the mainstay of treatment for cases with unresectable cancer entities. However, for those patients with hypovascular tumors or impaired liver function reserve, TACE is a suboptimal treatment option. For example, embolization does not result in complete coverage of a hypovascular tumor, and may rather promotes postoperative tumor recurrence, or leave residual tumor, in these TACE-resistance patients. In addition, TACE carries a higher risk of hepatic decompensation in patients with poor liver function or reserve.

Non-vascular interventional locoregional therapies for HCC include radiofrequency ablation (RFA), microwave ablation (MWA), high-intensity focused ultrasound (HIFU), laser-induced thermotherapy (LITT), cryosurgical ablation (CSA), irreversible Electroporation (IRE), percutaneous ethanol injection (PEI), and brachytherapy. Recent advancements in these techniques have significantly improved the treatment efficacy of HCC and expanded the population of patients who qualify for treatment. This review embraces the current status of imaging-guided locoregional non-intravascular interventional treatments for HCCs, with a primary focus on the clinical evaluation and assessment of the efficacy of combined therapies using these interventional techniques.

Percutaneous Therapies for Hepatocellular Carcinoma: Evolution of Liver Directed Therapies

Percutaneous ablation is a mainstay of treatment for early stage, unresectable hepatocellular carcinoma (HCC). Recent advances in technology have created multiple ablative modalities for treatment of this common malignancy. The purpose of this review is to familiarize readers with the technical and clinical aspects of both existing and emerging percutaneous treatment options for HCC.

Metastatic disease to the liver: Locoregional therapy strategies and outcomes

Secondary cancers of the liver are more than twenty times more common than primary tumors and are incurable in most cases. While surgical resection and systemic chemotherapy are often the first-line therapy for metastatic liver disease, a majority of patients present with bilobar disease not amenable to curative local resection. Furthermore, by the time metastasis to the liver has developed, many tumors demonstrate a degree of resistance to systemic chemotherapy. Fortunately, catheter-directed and percutaneous locoregional approaches have evolved as major treatment modalities for unresectable metastatic disease. These novel techniques can be used for diverse applications ranging from curative intent for small localized tumors, downstaging of large tumors for resection, or locoregional control and palliation of advanced disease. Their use has been associated with increased tumor response, increased disease-free and overall survival, and decreased morbidity and mortality in a broad range of metastatic disease. This review explores recent advances in liver-directed therapies for metastatic liver disease from primary colorectal, neuroendocrine, breast, and lung cancer, as well as uveal melanoma, cholangiocarcinoma, and sarcoma. Therapies discussed include bland transarterial embolization, chemoembolization, radioembolization, and ablative therapies, with a focus on current treatment approaches, outcomes of locoregional therapy, and future directions in each type of metastatic disease.

Challenges Facing Percutaneous Ablation in the Treatment of Hepatocellular Carcinoma: Extension of Ablation Criteria

As an emerging minimally invasive treatment method, percutaneous ablation is more and more widely used in the treatment of liver tumors. It has been recommended by guidelines for diagnosis and treatment of hepatocellular carcinoma (HCC) as a curative treatment alongside surgical resection and liver transplantation. In recent years, with the continuous advancement and innovation of percutaneous ablation technologies, their clinical efficacy and safety have been significantly improved, which has led to the expanded application of percutaneous ablation in the treatment of HCC—more and more patients who were previously considered unsuitable for ablation therapies are now being treated with percutaneous ablation. Obviously, percutaneous ablation can reduce the risk of treatment changes from curative strategies to palliative strategies. Based on clinical practice experience, this review enumerates the advantages and disadvantages of different ablative modalities and summarizes the existing combinations of ablation techniques, thus will help clinicians choose the most appropriate ablative modality for each patient and will provide scientific guidance for improving prognosis and making evidence-based treatment decisions. In addition, we point out the challenges and future prospects of the ablation therapies, thereby providing direction for future research.

A review on radiofrequency, microwave and high-intensity focused ultrasound ablations for hepatocellular carcinoma with cirrhosis

Importance

Hepatocellular carcinoma (HCC) is usually accompanied by liver cirrhosis, which makes treatment of this disease challenging. Liver transplantation theoretically provides an ultimate solution to the disease, but the maximal surgical stress and the scarcity of liver graft make this treatment option impossible for some patients. In an ideal situation, a treatment that is safe and effective should provide a better outcome for patients with the dilemma.

Objective

This article aims to give a comprehensive review of various types of loco-ablative treatment for HCC.

Evidence Review

Loco-ablative treatment bridges the gap between surgical resection and transarterial chemotherapy. Various types of ablative therapy have their unique ability, and evidence-based outcome analysis is the most important key to assisting clinicians to choose the most suitable treatment modality for their patients.

Findings

Radiofrequency ablation (RFA) has a relatively longer history and more evidence to support its effectiveness. Microwave ablation (MWA) is gaining momentum because of its shorter ablation time and consistent ablation zone. High-intensity focused ultrasound (HIFU) ablation is a relatively new technology that provides non-invasive treatment for patients with HCC. It has been carried out at centers of excellence and it is a safe and effective treatment option for selected patients with HCC and liver cirrhosis.

Conclusion and Relevance

Selective use of different loco-ablative therapies will enhance clinicians' treatment options for treatment of HCC.

Advanced Techniques in the Percutaneous Ablation of Liver Tumours

Percutaneous ablation is an accepted treatment modality for primary hepatocellular carcinoma (HCC) and liver metastases. The goal of curative ablation is to cause the necrosis of all tumour cells with an adequate margin, akin to surgical resection, while minimising local damage to non-target tissue. Aside from the ablative modality, the proceduralist must decide the most appropriate imaging modality for visualising the tumour and monitoring the ablation zone. The proceduralist may also employ protective measures to minimise injury to non-target organs. This review article discusses the important considerations an interventionalist needs to consider when performing the percutaneous ablation of liver tumours. It covers the different ablative modalities, image guidance, and protective techniques, with an emphasis on new and advanced ablative modalities and adjunctive techniques to optimise results and achieve satisfactory ablation margins.

Portal Vein Tumor Thrombus: No Longer a Death Sentence

Hepatocellular carcinoma (HCC) is the most common malignancy of the liver and a leading cause of cancer mortality worldwide. HCC commonly results from longstanding liver cirrhosis, which presents a host of complications and a severely diminished quality of life. Despite advancements in diagnosis, molecular pathogenesis, and management of the complications associated with irreversible liver diseases, HCC remains an aggressive malignancy with high mortality. HCC is often invasive to adjacent vasculature, including the inferior vena cava (IVC) and portal veins, which present with rapid morbidity and patient decline. This article describes a patient with cirrhosis and HCC previously treated with cryoablation now presenting with multiple new foci and invasion of the left medial portal vein. These lesions were synchronously cryoablated. Cryoablation is typically reserved for solid tumor masses within the soft tissue or specific organs. This report illustrates a technique of directly cryoablating tumors within vessels. We achieved adequate cryoablation of the intravascular HCC portal vein tumor thrombus in the left medial portal vein. A one-month follow-up CT scan demonstrated significant portal vein macrovascular invasion (MVI) regression from 22.8 mm to 7.7 mm. Portal vein invasion by HCC presents unique challenges and traditionally precludes percutaneous or surgical therapy. Our technique shows successful cryoablation of MVI as a viable adjunct to treatment in select patients.

Overall survival and local recurrence following RFA, MWA, and cryoablation of very early and early HCC: a systematic review and Bayesian network meta-analysis

OBJECTIVE

To compare overall survival (OS) and local recurrence (LR) following radiofrequency ablation (RFA), microwave ablation (MWA), and cryoablation (CA) for very early and early hepatocellular carcinoma (HCC).

METHODS

This systematic review was performed according to the PRISMA guidelines. MEDLINE, Embase, and Cochrane databases were searched. Randomized controlled trials (RCTs) and observational studies were included. OS and LR at 1 year and 3 years were assessed. OS was reported as hazard ratio (HR) with 95% credible intervals (CrI) and LR as relative risk (RR) with 95% CrI, to summarize effect of each comparison.

RESULTS

Nineteen studies (3043 patients), including six RCTs and 13 observational studies, met inclusion criteria. For OS at 1 year, as compared to RFA, CA had HR of 0.81 (95% CrI: 0.43-1.51), and MWA had HR of 1.01 (95% CrI: 0.71-1.43). For OS at 3 years, as compared to RFA, CA had HR of 0.90 (95% CrI: 0.48-1.64) and MWA had HR of 1.07 (95% CrI: 0.73-1.50). For LR at 1 year, CA and MWA had RR of 0.75 (95% CrI: 0.45-1.24) and 0.93 (95% CrI: 0.78-1.14), respectively, as compared to RFA. For LR at 3 years, CA and MWA had RR of 0.96 (0.74-1.23) and 0.98 (0.87-1.09), respectively, as compared to RFA. Overall, none of the comparisons was statistically significant. Age of patients and tumor size did not influence treatment effect.

CONCLUSIONS

RFA, MWA, and CA are equally effective for locoregional treatment of very early and early HCC.

KEY POINTS

• There is no significant difference in the OS and LR (at 1 year and 3 years) following ablation of very early and early HCC with RFA, MWA, and CA. • There was no effect of tumor size on the treatment efficacy. • More RCTs comparing CA with RFA and MWA should be performed.

Percutaneous Cryoablation of Liver Tumors: Initial Experience from a Tertiary Care Center in India

BACKGROUND

Percutaneous ablation is an important part of management strategy for liver tumors. While radiofrequency ablation and microwave ablation are the most widely used ablative techniques, cryoablation (CA) has several technical advantages but has been underused till recently. In this study, we report the initial experience with percutaneous CA of liver tumors.

METHODS

This was a retrospective evaluation of consecutive patients with liver tumors who underwent percutaneous CA between October 2018 and August 2019. The ablation procedures were performed under combined ultrasound and computed tomography guidance using argon-helium-based CA systems. The baseline tumor characteristics (including size and location), Barcelona Clinic Liver Cancer stage, and Child-Pugh score were recorded. Each patient underwent a follow-up after 1 month and at 3 months subsequently. Technical success, complete response, local tumor progression, and overall survival were evaluated.

RESULTS

Nine patients (mean age, 62.4 years, median age, 66 years, five men and four women) with 10 liver tumors (mean size, 2.22 cm) underwent CA. Seven (77.8%) patients had hepatocellular carcinoma (HCC), and 2 patients had solitary liver metastasis. One patient with HCC had two lesions, while the rest had only one lesion. Of the two metastatic lesions, one was from carcinoma of the cervix and the other was from jejunal neuroendocrine tumor. Five tumors were located adjacent to the gallbladder, two lesions were adjacent to the right portal vein, two lesions were subcapsular, and one lesion was adjacent to the stomach. Technical success was achieved in all the patients. Complete response was achieved in 7 (77.8%) patients. The median follow-up period was 7 months (range, 3-12 months). There was no local tumor progression and no death during the follow-up period. No procedure-related complication was seen.

CONCLUSION

Percutaneous CA of hepatic tumors is technically feasible and is a safe and effective ablative technique.

Percutaneous cryoablation in early stage hepatocellular carcinoma: analysis of local tumor progression factors

PURPOSE

We aimed to evaluate the effectiveness and safety of percutaneous cryoablation (PC) for early or very early stage hepatocellular carcinoma (HCC) and assess the risk factors for local tumor progression (LTP) after PC.

METHODS

A total of 45 treatment-naïve patients treated with PC for early or very early stage HCCs were included in this retrospective study. The safety of PC was assessed by evaluating procedure-related complications and comparing hepatic function before and after the procedure. The effectiveness was assessed by evaluating technical success, LTP rates, and disease progression (DP) rates. Prognostic factors associated with LTP after PC were also analyzed.

RESULTS

Technical success and complete response were achieved in all patients (100%) by 1 month after PC. During a mean of 28.1±15.6 months of follow-up, the incidences of LTP and DP were 11.1% and 37.8%, respectively. The LTP-free and DP-free survival rates were 93.3% and 84.4% at 1 year and 88.9% and 62.2% at 2 years, respectively. Hepatic function was normalized within 3 months after PC. There were no major complications and only one minor complication of small hematoma. On univariate and multivariate analysis, minimal ablative margin <5 mm was the only significant risk factor associated with LTP.

CONCLUSION

PC is a safe and effective therapy for patients with early or very early stage HCC. Minimal ablative margin <5 mm was a significant prognostic factor for LTP.

The role of interventional radiology in the treatment of patients with pancreatic cancer

Interventional radiology (IR) provides minimally invasive therapeutic and palliative options for the treatment of pancreatic cancer depending on the stage of the disease. IR plays a critical, and also a very effective role, in both pre- and post-operative care of the patients with early stage resectable disease and also in palliative treatment of the patients with locally advanced or metastatic disease. In this article, we aimed to present the capability and the limitations of IR procedures including: local treatment options of primary and metastatic pancreatic cancer, palliation of biliary and intestinal obstructions, minimally invasive treatment of post-operative complications, and pain management.

Computed tomography-guided argon-helium cryoablation for sacrum chordoma

We examined the therapeutic effects of argon-helium cryoablation guided by computed tomography (CT) in the treatment of sacral chordoma.This is a retrospective study. CT-guided argon-helium cryoablation was used to treat 9 sacral chordoma patients at our centers between January 2016 and June 2019. We collected data on treatment response and success. Data from long-term follow-up of treatment outcomes were also assessed.All patients were treated successfully according to the indicated technical parameters. There were no reports of procedure-related complications from any of the patients. Complete response (CR) was also achieved in all patients. Six patients (66.7%) achieved initial CR after 1 treatment session and 3 patients (33.3%) achieved secondary CR after 2 treatment sessions. The chordoma-related symptoms improved significantly in all patients after treatment. The mean visual analogue scale score improved from 7.3 before treatment to 4.2 after treatment (P < .001). The mean function score improved from 3.2 before treatment to 1.4 after treatment (P < .001). The median length of follow-up for all patients was 33 months (range: 6-46 months). All patients were alive during the follow-up. Two (22.2%) patients experienced local recurrence (LR) at 6 and 9 months after treatment, respectively. These patients had revised treatment with trans-arterial embolism (n = 1) or repeat ablation (n = 1). The median progression-free survival was 36.8 months.Treatment of sacral chordoma with CT-guided argon-helium cryoablation is effective and offers a potentially beneficial therapeutic alternative for patients with the condition.

Recent progress in treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related death worldwide. In the past decade, there have been improvements in non-drug therapies and drug therapies for HCC treatment. Non-drug therapies include hepatic resection, liver transplantation, transarterial chemoembolization (TACE) and ablation. The former two surgical treatments are beneficial for patients with early and mid-stage HCC. As the first choice for non-surgical treatment, different TACE methods has been developed and widely used in combination therapy. Ablation has become an important alternative therapy for the treatment of small HCC or cases of unresectable surgery. Meanwhile, the drugs including small molecule targeted drugs like sorafenib and lenvatinib, monoclonal antibodies such as nivolumab are mainly used for the systematic treatment of advanced HCC. Besides strategies described above are recommended as first-line therapies due to their significant increase in mean overall survival, there are also potential drugs in clinical trials or under preclinical development. In addition, a number of potential preclinical surgical or adjuvant therapies are being studied, such as oncolytic virus, mesenchymal stem cells, biological clock, gut microbiome composition and peptide vaccine, all of which have shown different degrees of inhibition on HCC. With some potential anti-HCC drugs being reported, many promising therapeutic targets in related taxonomic signaling pathways including cell cycle, epigenetics, tyrosine kinase and so on that affect the progression of HCC have also been found. Together, the rational application of existing therapies and drugs as well as the new strategies will bring a bright future for the global cure of HCC in the coming decades.

Unresectable Hepatocellular Carcinoma: Transcatheter Arterial Chemoembolization Combined With Microwave Ablation vs. Combined With Cryoablation

Background: Transcatheter arterial chemoembolization (TACE) combined with ablation has been widely used for treating unresectable hepatocellular carcinoma (HCC). However, the technique with which TACE should be combined for it to be more effective remains unknown. Purpose: To retrospectively evaluate the efficacy and safety of TACE combined with microwave ablation (MWA) vs. TACE combined with cryoablation (CRA) in treating unresectable HCC. Materials and Methods: From January 2011 to December 2018, 108 patients diagnosed with unresectable HCC were divided into either the TACE-MWA group (n = 48) or TACE-CRA group (n = 60). Overall survival (OS) and time to progression (TTP) were compared between the two groups. To reduce potential bias, a propensity score matching (PSM) was performed. Complications were observed. Kaplan-Meier survival curves were constructed and compared using the log-rank test. Results : The baseline characteristics of the two groups were balanced. The median OS was 20.9 months (95% CI 14.3-27.6 months) in the TACE-MWA group and 13.0 months (95% CI 8.8-17.1 months) in the TACE-CRA group (P = 0.096). The median TTP was 8.8 months (95% CI 4.3-13.4 months) in the TACE-MWA group and 9.3 months (95% CI 7.1-11.5 months) in the TACE-CRA group (P = 0.675). After PSM, 48 patients remained in each group. The median OS in the TACE-MWA and TACE-CRA groups was 20.9 months (95% CI 14.3-27.6 months), and 13.5 months (95% CI 8.4-18.6 months, P = 0.100), respectively. The median TTP in the TACE-MWA and TACE-CRA groups was 8.8 months (95% CI 4.3-13.4 months), and 8.6 months (95% CI 3.1-14.2 months, P = 0.909), respectively. The overall incidence rate of ablation-related complications was lower in the TACE-MWA group than in the TACE-CRA group (66.7 vs. 88.3%, P = 0.006). Multivariate analysis showed that the presence of portal vein tumor thrombus (PVTT) and the maximum diameter of intrahepatic tumor were significant prognostic factors for OS and TTP. Conclusion: The efficacy of TACE-MWA and TACE-CRA in the treatment of unresectable HCC was comparable. TACE-MWA was more promising because of a lower complication rate, especially with regard to thrombocytopenia. Further prospective randomized controlled trials are required to validate our findings.

Breast cancer care during a pandemic: an opportune time for cryoablation?

Purpose

Cryoablation is a minimally-invasive percutaneous procedure that is capable of reducing the psychosocial burden of surgical delay while also decreasing the morbidity of breast cancer therapy. The purpose of this editorial is to discuss the potential role of cryoablation for reducing the psychosocial burden of surgical delay during the COVID-19 pandemic by expediting the management of breast cancer while also lessening demand on limited healthcare resources.

Methods

This editorial critiques current expert opinion recommendations that aim to reduce viral transmission and preserve healthcare resources during the COVID-19 pandemic by advocating delay of elective breast cancer surgery.

Results

The editorial summarizes the current state of the evidence that supports the selective use of cryoablation as a definite or stopgap measure in the management of breast cancer during the COVID-19 pandemic or when healthcare resources are limited.

Conclusions

As an office-based procedure performed under local anesthesia, cryoablation eliminates the need for operating room personnel and equipment while also reducing the psychosocial impact of delayed breast cancer surgery. By reducing the number of patient and healthcare provider interactions, cryoablation not only decreases the risk of viral transmission but also the need for personal protective devices during resource-limited times.

Computed Tomography-Guided Percutaneous Cryoablation for ‎ Subcardiac Hepatocellular Carcinoma: Safety, Efficacy, Therapeutic Results and Risk Factors for Survival Outcomes

Objective

To investigate the clinical safety, efficacy, therapeutic outcomes and risk factors of computed tomography-guided percutaneous cryoablation (CT-PCRA) for subcardiac hepatocellular carcinoma (HCC).

Patients and Methods

In this study, patients with single HCC nodules located on the left lobe who subsequently underwent CT-PCRA were reviewed from July 2012 to August 2016. According to the definition of subcardiac HCC, the patients were grouped into the subcardiac HCC group (n=33) and the non-subcardiac HCC group (n=40). The technical success rates, tumour response rates, oncological outcomes including overall survival (OS) and recurrence-free survival (RFS) and complications were compared. Multivariate analysis was performed on clinicopathological variables to identify factors affecting long-term outcomes.

Results

Seventy-three patients with subcardiac HCC were included in this study. After a median follow-up time of 37.8 months, 27.4% (20/73) of the patients died. The technical success and complete response rates were not significantly different between the two groups (p = 1.000; p = 0.590). The cumulative OS and RFS of the subcardiac HCC group were comparable to those of the non-subcardiac HCC group (p =0.820, p =0.922). Two major complications, intra-abdominal bleeding and right pleural effusion, were found at 2.2 and 3.1 months in the subcardiac HCC group, which were comparable with those in the non-subcardiac HCC group (p = 0.683). The multivariate analysis results showed that older age (hazard ratio [HR]: 2.382, 95% confidence interval [CI]: 1.884–7.823; p = 0.038) and ALBI grade 2–3 (HR: 3.398, 95% CI: 1.950–6.058; p = 0.021) may be predictors of poor OS and that tumour size ≥3 cm in diameter (HR: 3.302, 95% CI: 2.232–8.293; p = 0.012) may be a predictor of poor RFS.

Conclusion

CT-PCRA for subcardiac HCC can be performed safely and efficiently and contribute to improving survival prognosis.

Assessment in the Survival Outcome After Transarterial Chemoembolization Combined with Cryoablation for Hepatocellular Carcinoma (Diameter > 4cm) Based on the Albumin-Bilirubin Grade and Platelet-Albumin-Bilirubin ‎grade: ‎ A Preliminary Study

Objective

Based on the albumin-bilirubin (ALBI) and platelet-albumin-bilirubin (PALBI) grade to assess the long-term outcomes of patients with large hepatocellular carcinoma (HCC) after transarterial chemoembolization combined with cryoablation (TACE-CRA).

Materials and Methods

We studied 86 patients with HCC nodules (up to 3 HCCs with maximum diameters of 4.1–12.0 cm) who subsequently underwent TACE-CRA from July 2007 to August 2018. The overall survival (OS) was compared between groups classified by ALBI and PALBI grade. Baseline characteristics were collected to identify the risk factors for determination of poor OS after TACE-CRA. The prognostic performances of CTP class, ALBI and PALBI grade were compared.

Results

After a median follow-up time of 33.8 months, 41 patients had died. The cumulative1-, 3- and 5-year OS rates were 74.5%, 38.0% and 29.3%, respectively. Stratified according to ALBI grade, the cumulative 3- and 5-year OS rates were 41.2% and 41.2% in grade 1, respectively, and 20.9% and 9.8% in grades 2–3, respectively (P < 0.001). Stratified according to PALBI grade, the cumulative 3- and 5-year OS rates were 41.2% and 37.5% in grade 1, respectively, and 36.3% and 21.2% in grades 2–3, respectively (P = 0.002). Multivariate analysis results showed that older age, and ALBI grade 2–3 were associated with overall mortality. ALBI grade demonstrated significantly greater area under the curve values than CTP class and PALBI in predicting 1-, 3- and 5-year OS.

Conclusion

ALBI grade offers accurate prediction of long-term outcome for patients with HCC (diameter > 4 cm) after TACE-CRA.

Cryoablation combined with radiotherapy for hepatic malignancy: Five case reports

BACKGROUND

The survival of patients treated with monotherapy for hepatic malignancies is not ideal. A comprehensive program of cryoablation combined with radiotherapy for the treatment of hepatic malignancies results in less trauma to the patients. It may provide an option for the treatment of patients with advanced hepatic malignancies.

CASE SUMMARY

We reported 5 cases of advanced-stage hepatic malignancies treated in our hospital from 2017-2018, including 3 cases of primary hepatocellular carcinoma and 2 cases of metastatic hepatic carcinoma. They first received cryoablation therapy on their liver lesions. The procedure consisted of 2 freeze-thaw cycles, and for each session, the duration of freezing was 13-15 min, and the natural re-warming period was 2-8 min. Depending on the tumor size, the appropriate cryoprobes were selected to achieve complete tumor ablation to the greatest extent possible. After cryoablation surgery, intensity-modulated radiotherapy (IMRT) for liver lesions was performed, and the radiotherapy regimen was 5400 cGy/18f and 300 cGy/f. None of the 5 patients had adverse events above grade II, and their quality of life was significantly improved. Among them, 4 patients were free of disease progression in the liver lesions under local control, and their survival was prolonged; 3 patients are still alive.

CONCLUSION

Our clinical practice demonstrated that cryoablation combined with IMRT could be implemented safely. The definitive efficacy for hepatic malignancies needs to be confirmed in larger-size sample prospective studies.

Percutaneous cryoablation for the treatment of liver cancer at special sites: an assessment of efficacy and safety

Background

To assess the safety and efficacy of cryoablation (CA) devices for the treatment of liver cancer at special sites in a retrospective study.

Methods

Special site liver cancer was defined as the tumors directly abutting surrounding structures (such as the liver capsule, gallbladder, vessel, diaphragm, intestine, and adrenal gland) with a maximum distance of 1.0 cm between the tumor and these organs. Sixty-six patients (49 men, 17 women; mean age, 60.8 years; age range, 27-82 years) were included. CA procedure was performed to treat 69 tumors under the guidance of computed tomography or ultrasound. Local tumor progression was assessed during the follow-up. A visual analog scale (VAS) evaluated the pain degree. Complications were assessed during and after every procedure.

Results

The number of tumors under the liver capsule and adjacent to the gallbladder, portal or hepatic vein, diaphragm, intestine, and adrenal gland were 29, 5, 8, 14, 7, and 6, respectively. The median follow-up time was 14 months (range, 2-28 months). In the 69 procedures, the technical success rate was 100%. The cumulative local tumor progression rates at 6, 9, 15, and 24 months were 10.2%, 16.5%, 20.9%, and 30.5%, respectively. No cases of serious complications occurred. During operation, the occurrence rates of subcapsular hemorrhage and pneumothorax were 2.9% and 1.4%, respectively. After the operation, the occurrence rate of biloma, capsular injury, subcapsular planting metastasis, and pneumothorax were 1.4%, 18.8%, 1.4%, and 2.8%, respectively. The average score of 66 patients with a VAS was 2.15±0.63 during the operation.

Conclusions

Percutaneous CA is safe and effective for patients with special site liver cancer.

Image-Guided Percutaneous ‎Microwave Ablation Versus Cryoablation For Hepatocellular Carcinoma In High-Risk Locations: Intermediate-Term Results

Objective

The aims of this study were to compare the clinical outcomes between image-guided percutaneous microwave ablation (MWA) and cryoablation (CRA) in patients with hepatocellular carcinoma (HCC) in high-risk locations and to identify the prognostic factors associated with the two treatment methods.

Methods

This retrospective study was institutional review board approved. A total of 120 patients (88 men and 32 women) with one hundred and thirty-four HCC lesions in high-risk locations from April 2014 to March 2018 were reviewed. Sixty-four patients underwent MWA and 56 patients underwent CRA. Survival, recurrence and complications were compared between the two groups. Effect of changes in key outcomes (i.e., overall survival (OS), recurrence-free survival (RFS) and local tumor progression (LTP)) was statistically analyzed with the log rank test. Univariate and multivariate analysis were performed on clinicopathological variables to identify factors affecting intermediate-term outcomes.

Results

The OS and RFS after MWA were comparable to those of CRA (P =0.141, and P=0.469, respectively). The LTP and major complication in MWA group was higher than those in CRA group (P=0.003, and P=0.039). Univariate analysis showed that age (P=0.007), tumor size (P=0.001), and Child-Turcotte-Pugh (CTP) grade (P=0.003) were risk factors for OS, and multivariate analysis results showed that older age (≥65 years) (P=0.002, HR:3.338, 95% CI:1.928–5.281), 3.0–5.0 cm in size (P<0.001, HR: 3.312, 95% CI: 1.872–4.489) and CTP grade B (P=0.001, HR:3.382, 95% CI: 1.882–5.902) were independently associated with poor OS.

Conclusion

CRA had comparable oncologic outcomes with MWA and could be a safe and effective treatment for HCC in high-risk locations.

Individualized Ablation of Hepatocellular Carcinoma: Tailored Approaches across the Phenotype Spectrum

Ablation is now recommended by international guidelines for the definitive treatment of hepatocellular carcinoma (HCC). Extensive clinical studies have demonstrated outcomes comparable to surgical resection with shorter hospital stays, decreased costs, and improved quality of life. Successful ablation requires complete treatment of both tumor and margin while preserving critical adjacent structures. HCC exhibits highly variable presentations in both anatomic involvement and biology which have significant implications on choice of ablative therapy. There are now abundant ablation modalities and adjunctive techniques which can be used to individualize ablation and maximize curative results. This article provides a patient-centered summary of approaches to HCC ablation in the context of patient performance, hepatic reserve, tumor phenotype and biology, intra- and extrahepatic anatomy, and ablation technology.

Locoregional treatments for hepatocellular carcinoma: Current evidence and future directions

Liver cancers are the second most frequent cause of global cancer-related mortality of which 90% are attributable to hepatocellular carcinoma (HCC). Despite the advent of screening programmes for patients with known risk factors, a substantial number of patients are ineligible for curative surgery at presentation with limited outcomes achievable with systemic chemotherapy/external radiotherapy. This has led to the advent of numerous minimally invasive options including but not limited to trans-arterial chemoembolization, radiofrequency/microwave ablation and more recently selective internal radiation therapy many of which are often the first-line treatment for select stages of HCC or serve as a conduit to liver transplant. The authors aim to provide a comprehensive overview of these various image guided minimally invasive therapies with a brief focus on the technical aspects accompanied by a critical analysis of the literature to assess the most up-to-date evidence from comparative systematic reviews and meta-analyses finishing with an assessment of novel combination regimens and future directions of travel.

Analysis of the feasibility of microwave ablation for colorectal liver metastases: a preliminary report

Introduction

Colorectal liver metastasis is a challenge in the treatment of colorectal cancer and an important factor affecting the prognosis of patients. Currently, microwave ablation has gradually been applied for the treatment of liver cancers as a type of thermal ablation. However, there are no large-scale studies on the effectiveness of microwave ablation for colorectal liver metastases.

Aim

To investigate the efficacy of microwave ablation and liver resection for liver metastases from colorectal cancer, and to compare the prognosis between patients treated with microwave ablation and those in the SEER (Surveillance, Epidemiology, and End Results, National Cancer Institute) database.

Material and methods

We retrospectively analyzed the clinical data of 24 patients with colorectal liver metastasis who underwent radical colorectal cancer resection and liver microwave ablation (the MWA group) and 12 patients who received radical colorectal cancer resection and liver resection (the LR group). The complete ablation rate and complications after microwave ablation were observed. Survival analysis was performed for cases treated with liver resection and cases from the SEER database.

Results

A total of 53 tumors were ablated in the 24 patients who underwent radical colorectal cancer resection and liver microwave ablation; 52 tumors achieved complete ablation after the first ablation (98.1%). No serious complications occurred in the MWA group, and long-term survival was not significantly different between the MWA and other groups.

Conclusions

Microwave ablation for colorectal liver metastases avoids extensive liver resection while ensuring therapeutic efficacy; the operation is safe, feasible, and reproducible.

MRI-Guided Cryoablation of Hepatic Dome Hepatocellular Carcinomas Using 1-T Open High-Field-Strength Scanner

OBJECTIVE. The objective of our study was to prospectively evaluate the feasibility, safety, and effectiveness of 1-T open MRI-guided percutaneous cryoablation of hepatic dome hepatocellular carcinomas (HCCs). SUBJECTS AND METHODS. Thirty-seven patients with 37 hepatic dome HCCs underwent MRI-guided percutaneous cryoablations. MR fluoroscopy with a freehand technique was applied in the procedure. All lesions ranged in size from 8 to 38 mm. Patients were followed for at least 12 months after cryoablation or until death. Survival period, local tumor control, and complications were recorded. RESULTS. MRI-guided percutaneous cryoablation procedures were successfully performed on all 37 lesions. The technical success rate was 100%. The median follow-up time was 21.0 months (range, 10-26 months). Two patients with local tumor progression at the 4th and 11th month after the procedure were treated with a supplementary cryoablation. One patient died of upper gastrointestinal hemorrhage at the 10th month after cryoablation. Local tumor progression and overall survival rates were 2.7% (1/37) and 100% (37/37) at 6 months and 5.4% (2/37) and 97.3% (36/37) at 1 year, respectively. Postoperative hydrothorax that required chest tube drainage occurred in two patients; no other severe complications occurred. CONCLUSION. Cryoablation of hepatic dome HCCs with 1-T open MRI guidance is a feasible, safe, and effective therapy method.

Safety and Efficacy of Percutaneous Cryoablation for Small Hepatocellular Carcinomas Adjacent to the Heart

PURPOSE

This study evaluated the safety and efficacy of percutaneous cryoablation for treatment of the left subdiaphragmatic small hepatocellular carcinomas (HCCs) adjacent to the heart.

MATERIALS AND METHODS

Between September 2013 and March 2018, 189 consecutive patients underwent cryoablation for small HCCs (≤3 cm); 70 patients (mean: 61.3 ± 10.6 years of age; range: 40-82 years) with left hepatic tumors (22 juxtacardiac and 48 nonjuxtacardiac tumors) were retrospectively analyzed. Patients were divided into juxtacardiac and nonjuxtacardiac tumor groups (tumor margins: ≤10 mm and >10 mm, respectively, from the heart border). The rates of technical success, complete ablation, complications, and local tumor recurrence (LTR) were evaluated.

RESULTS

No significant intergroup differences were observed in the mean diameter of the tumor (17.9 ± 5.5 mm vs. 17.5 mm ± 5.2, respectively; P = 0.781) and of the ablation zone (41.3 ± 4.2 mm vs. 43.5 ± 5.8 mm, respectively; P = 0.115). Technical success was achieved in all patients. No procedure-related major complications occurred in either group. The median follow-up period was 15 months (range: 3.1-49.6 months). No statistically significant intergroup differences were observed in the rates of complete ablation (90.9% vs. 93.8%, respectively; P = 0.646) and LTR (20% vs. 15.6%, respectively; P = 0.725).

CONCLUSIONS

Cryoablation is a safe treatment modality for patients with juxtacardiac small HCCs, without an increased risk of cardiac complications compared to treatment of HCCs that are nonjuxtacardiac, and with comparable efficacy.

Computed tomography-guided cryoablation for adrenal metastases: local control and survival

To evaluate the feasibility, local control, and survival after computed tomography (CT)-guided cryoablation for adrenal metastases.This study included 31 consecutive patients with adrenal metastases who were treated by CT-guided cryoablation in our center from July 2011 to October 2017. The technical success rate, local progression rate, local progression-free survival (LPFS), systemic progression-free survival (SPFS), and overall survival were assessed. The predictors of survival were determined using univariate and multivariate Cox regression analyses.The primary and secondary technical success rates were 90.3% and 100%, respectively. None of the patients experienced a hypertensive crisis. The local progression rate during follow-up was 19.4%. Systemic progression was found in 9 patients. The cumulative 1-, 3-, and 5-year LPFS rates were 80.6%, 37.8%, and 18.4%, respectively. The cumulative 1-, 3-, and 5-year SPFS rates were 77.4%, 31.9%, and 14.6%, respectively. The cumulative 1-, 3-, and 5-year overall survival rates were 83.9%, 45.0%, and 30.0%, respectively. The existence of an extra-adrenal tumor was a significant independent predictor of worse overall survival (P = .012). The mean overall survival durations were significantly different between patients with and without an extra-adrenal tumor (16.6 ± 2.4 vs 50.9 ± 4.5 months, P <.001).Our findings support that CT-guided cryoablation is a safe and effective method for controlling adrenal metastases and imply that this approach may improve the survival of patients with adrenal metastases.

Percutaneous treatment of hepatocellular carcinoma: State of the art and innovations

Percutaneous treatment of hepatocellular carcinoma (HCC) encompasses a vast range of techniques, including monopolar radiofrequency ablation (RFA), multibipolar RFA, microwave ablation, cryoablation and irreversible electroporation. RFA is considered one of the main curative treatments for HCC of less than 5 cm developing on cirrhotic liver, together with surgical resection and liver transplantation. However, controversies exist concerning the respective roles of ablation and liver resection for HCC of less than 3 to 5 cm on cirrhotic liver. In line with the therapeutic algorithm of early HCC, percutaneous ablation could also be used as a bridge to liver transplantation or in a sequence of upfront percutaneous treatment, followed by transplantation if the patient relapses. Moreover, several innovations in ablation methods may help to efficiently treat early HCC, initially considered as "non-ablatable", and might, in some cases, extend ablation criteria beyond early HCC, enabling treatment of more patients with a curative approach.

3.0T MRI for long-term observation of lung nodules post cryoablation: a pilot study

BACKGROUND

The purpose of this study was to use serial magnetic resonance imaging (MRI) examinations to observe changes in malignant lung tumors over time post-cryoablation.

METHODS

The study protocol was approved by Institutional Review Board, and written informed consent was obtained from each participant in accordance with the Declaration of Helsinki. Patients with primary or metastatic lung tumors eligible for cryoablation were included in this prospective study. Cryoablation was performed according to standard procedures. Unenhanced and dynamic contrast-enhanced MRI scans were performed pre-cryoablation and at 1 day, 1 week, and 3-, 6-, and 12 months after cryoablation. At each time point, the signal intensity of the ablated zone on both T₁WI and T₂WI images, and volume and characteristics of the ablation zone were examined, and changes over time analyzed.

RESULTS

A total of 26 nodules in 23 patients were included in the study. The mean patient age was 53.7 ± 13.6 years, and 57.7% were males. Ablation zone volume increased to 1 week after the procedure, and then returned to baseline by 3 months. Cavitation post-cryoablation was found in 34.6% (9/26) of the nodules 1 month after treatment. Two types of time-signal intensity curves post-cryoablation were found: a straight line representing no definite enhancement from 1-day to 1-month, and an inflow curve representing mild delayed enhancement from month 3 to month 12. Local progression was associated with an incomplete hypointense rim around the ablation zone and absence of cavitation post-treatment.

CONCLUSIONS

Characteristic changes are present on MRI after cryoablation of lung tumors. A complete hypointense rim and cavitation may be signs of adequate treatment and that local tumor progression is less likely.

Percutaneous Image-Guided Cryoablation of Hepatic Tumors: Single-Center Experience With Intermediate to Long-Term Outcomes

OBJECTIVE

The purpose of this article is to report our intermediate to long-term outcomes with image-guided percutaneous hepatic tumor cryoablation and to evaluate its technical success, technique efficacy, local tumor progression, and adverse event rate.

MATERIALS AND METHODS

Between 1998 and 2014, 299 hepatic tumors (243 metastases and 56 primary tumors; mean diameter, 2.5 cm; median diameter, 2.2 cm; range, 0.3-7.8 cm) in 186 patients (95 women; mean age, 60.9 years; range, 29-88 years) underwent cryoablation during 236 procedures using CT (n = 126), MRI (n = 100), or PET/CT (n = 10) guidance. Technical success, technique efficacy at 3 months, local tumor progression (mean follow-up, 2.5 years; range, 2 months to 14.6 years), and adverse event rates were calculated.

RESULTS

The technical success rate was 94.6% (279/295). The technique efficacy rate was 89.5% (231/258) and was greater for tumors smaller than 4 cm (93.4%; 213/228) than for larger tumors (60.0%; 18/30) (p < 0.0001). Local tumor progression occurred in 23.3% (60/258) of tumors and was significantly more common after the treatment of tumors 4 cm or larger (63.3%; 19/30) compared with smaller tumors (18.0%; 41/228) (p < 0.0001). Adverse events followed 33.8% (80/236) of procedures and were grade 3-5 in 10.6% (25/236) of cases. Grade 3 or greater adverse events more commonly followed the treatment of larger tumors (19.5%; 8/41) compared with smaller tumors (8.7%; 17/195) (p = 0.04).

CONCLUSION

Image-guided percutaneous cryoablation of hepatic tumors is efficacious; however, tumors smaller than 4 cm are more likely to be treated successfully and without an adverse event.

Prognostic factors of hepatocellular carcinoma survival after radiofrequency ablation: A US population-based study

OBJECTIVE

To determine the survival outcome and prognostic factors of hepatocellular carcinoma (HCC) survival in patients who underwent radiofrequency ablation (RFA).

METHODS

The Surveillance, Epidemiology and End Results (SEER) database was queried: There were 2588 HCC patients from 2004 to 2012 who underwent RFA. The Kaplan-Meier curves and the multivariate Cox regression analysis were used to assess the prognostic factors.

RESULTS

With a median follow-up of 20 months, the 1-, 3- and 5-year overall survival (OS) rates were: 83%, 51% and 33%. Patients with a tumor size ≤5 cm in diameter had a better 5-year OS, as compared to patients with a tumor size >5 cm. The 5-year OS was significantly higher among patients with a normal level of alpha-fetoprotein (AFP), compared with those having elevated AFP. In an adjusted multivariate Cox regression analysis, those with ≥60 years of age (HR: 1.19; 95% CI 1.05-1.36), non-Asian race (HR: 1.53; 95% CI 1.30-1.81), tumor size >5 cm (HR: 1.43; 95% CI 1.24-1.65), elevated AFP (HR: 1.42; 95% CI 1.22-1.64), American Joint Committee on Cancer (AJCC) stages II-III (HR: 1.30; 95% CI 1.14-1.48) and the year of diagnosis from 2004-2007 (HR: 1.22; 95% CI 1.07-1.40) were significantly associated with a poor prognosis.

CONCLUSIONS

Age, race, tumor size, AFP level, AJCC stage and year of diagnosis were prognostic factors for OS in HCC patients who underwent RFA.

Safety and efficacy of a China-made cryoablation device in treatment of hepatocellular carcinoma smaller than 5 cm

AIM

To assess the safety and efficacy of a China-made cryoablation device in the treatment of hepatocellular carcinoma (HCC) smaller than 5 cm.

METHODS

A total of 33 patients with HCC smaller than 5 cm were treated by cryoablation using a China-made cryoablation device under the guidance of computed tomography. Operation-associated complications within and after procedures were evaluated. The efficacy of target lesions within procedures and local recurrence rate after procedures were evaluated with imaging modalities.

RESULTS

All 37 lesions of the 33 patients were successfully treated with a China-made cryablation device. Upon the finish of procedures, complete ablation was achieved in 83.78% (31/37) of lesions, and partial ablation was achieved in 16.22% (6/37). In a median follow-up period of 10.8 mo, 32 patients remained alive and 1 was lost to follow-up. The rate of local recurrence for target lesions was 30.3% (10/33), which is equal to that achieved with imported devices.

CONCLUSION

Our findings suggest that the China-made cryoablation device is safe and effective for HCC smaller than 5 cm with the capability of destroying the whole tumor lesion.