Combined resection and RFA in colorectal liver metastases: stratification of long-term outcomes

Meta-analysis of the prognostic value of serum carcinoembryonic antigen in patients with colorectal cancer liver metastases after hepatectomy

OBJECTIVES

Carcinoembryonic antigen (CEA) is a broad-spectrum tumor marker for differential diagnosis, monitoring, and response assessment of a variety of malignancies. This meta-analysis was aimed at evaluating whether serum CEA could predict the prognosis in patients with colorectal cancer liver metastasis (CRCLM) before and after liver resection (LR).

METHODS

PubMed, Embase, Cochrane, and Web of Science were systematically searched to retrieve literature, with a search cutoff date of 27 February 2023. Articles were strictly screened for inclusion according to pre-specified inclusion and exclusion criteria. Data were pooled and analyzed using Stata 16.0.

RESULTS

This meta-analysis included 36 studies involving a total of 11 143 CRCLM patients. The results showed that a high pre-LR serum CEA level was correlated with poor overall survival (OS: HR = 1.61, 95% CI = 1.49-1.75, P  < 0.001) and recurrence-free survival (RFS: HR = 1.27, 95% CI = 1.11-1.45, P  < 0.001) in CRCLM patients. A high post-LR serum CEA level predicted poor overall survival (OS: HR = 2.66, 95% CI = 2.10-3.38, P  < 0.001).

CONCLUSION

High preoperative and postoperative serum CEA levels in patients with CRCLM were significantly associated with poor prognosis, independent of treatment modality, mode of analysis, case origin, and cutoff value classification.

Trends and overall survival after combined liver resection and thermal ablation of colorectal liver metastases: a nationwide population-based propensity score-matched study

BACKGROUND

In colorectal liver metastases (CRLM) patients, combination of liver resection and ablation permit a more parenchymal-sparing approach. This study assessed trends in use of combined resection and ablation, outcomes, and overall survival (OS).

METHODS

This population-based study included all CRLM patients who underwent liver resection between 2014 and 2022. To assess OS, data was linked to two databases containing date of death for patients treated between 2014 and 2018. Hospital variation in the use of combined minor liver resection and ablation versus major liver resection alone in patients with 2-3 CRLM and ≤3 cm was assessed. Propensity score matching (PSM) was applied to evaluate outcomes.

RESULTS

This study included 3593 patients, of whom 1336 (37.2%) underwent combined resection and ablation. Combined resection increased from 31.7% in 2014 to 47.9% in 2022. Significant hospital variation (range 5.9-53.8%) was observed in the use of combined minor liver resection and ablation. PSM resulted in 1005 patients in each group. Major morbidity was not different (11.6% vs. 5%, P = 1.00). Liver failure occurred less often after combined resection and ablation (1.9% vs. 0.6%, P = 0.017). Five-year OS rates were not different (39.3% vs. 33.9%, P = 0.145).

CONCLUSION

Combined resection and ablation should be available and considered as an alternative to resection alone in any patient with multiple metastases.

Prognostic role of serum carcinoembryonic antigen in patients receiving liver resection for colorectal cancer liver metastasis: A meta-analysis

BACKGROUND

Carcinoembryonic antigen (CEA) is a broad-spectrum tumor marker for differential diagnosis, monitoring, and response assessment of a variety of malignancies.

AIM

To evaluate whether serum CEA could predict the prognosis in patients with colorectal cancer liver metastasis (CRCLM) before and after liver resection (LR).

METHODS

PubMed, Embase, Cochrane, and Web of Science were systematically searched to retrieve literature, with a search cut-off date of February 27, 2023. Articles were strictly screened for inclusion according to pre-specified inclusion and exclusion criteria. Data were pooled and analyzed using Stata 16.0.

RESULTS

This meta-analysis included 36 studies involving a total of 11143 CRCLM patients. The results showed that a high pre-LR serum CEA level was correlated with poor overall survival (OS) [hazard ratio (HR) = 1.61, 95% confidence interval (CI): 1.49-1.75, P < 0.001] and recurrence-free survival (HR = 1.27, 95%CI: 1.11-1.45, P < 0.001) in CRCLM patients. A high post-LR serum CEA level predicted poor OS (HR = 2.66, 95%CI: 2.10-3.38, P < 0.001). A comparison by treatment modality, analysis modality, patient source, and cutoff-value showed that overall, high preoperative and postoperative serum CEA levels remained correlated with a poor prognosis.

CONCLUSION

This study concluded that high pre-LR and post-LR serum CEA levels were significantly correlated with a poor prognosis in CRCLM patients.

The Effect of Cooling Fluid Composition on Ablation Size in Hepatic Laser Ablation: A Comparative Study in an Ex Vivo Bovine Setting

PURPOSE

Hyperthermic ablation is a minimally invasive mode of tumour therapy which serves as a viable alternative to surgical intervention. However, one of the major drawbacks, besides the heat sink effect and the risk of damaging adjacent organs, is limited ablation size. The use of a cooling fluid during ablation has been shown to increase the ablation volume and decrease the carbonisation rate. The aim of this study was to investigate whether the composition of the cooling fluid has an effect on ablation size and carbonisation rate during hepatic laser ablation in an ex vivo bovine setting.

METHOD

In this study bovine hepatic tissue was ablated in an ex vivo setting using an internally cooled laser applicator. A total of 45 tissue samples were assigned to three groups: 0.9% saline infusion (n = 15), distilled water infusion (n = 15) and a 50%/50% mixture of 0.9% saline and distilled water (n = 15). Ablation was conducted using a 1064 nm Nd:YAG laser at a wattage of 25 W and time interval of 10 min. The ablation volume and carbonisation rate were then measured and recorded through postprocedural MRI. One-way ANOVA and post-hoc testing were performed to assess the effect of the cooling fluid composition on the ablation volumes.

RESULTS

We found that using a mixture of saline and distilled water as a cooling fluid during hyperthermic ablation resulted in a larger ablation volume (mean ± SD: 22.64 ± 0.99 cm3) when compared to saline infusion (21.08 ± 1.11 cm3) or distilled water infusion (20.92 ± 0.92 cm3). This difference was highly significant (p < 0.001). There was no significant difference in ablation size between the saline group and the distilled water group. The highest carbonisation rate occurred in the saline group (12/15), followed by the mixed infusion group (3/15) and the distilled water group (1/15).

CONCLUSIONS

The results of this study suggest that cooling fluid composition during hepatic laser ablation affects ablation volume in an ex vivo bovine setting. There was no statistically significant difference when comparing ablation volumes during saline infusion and distilled water infusion, but the carbonisation rate was significantly higher when using saline. The combination of saline and distilled water in a 50%/50% mixture as cooling fluid appears to be an auspicious alternative, as ablation volumes created with it are larger when compared to saline and distilled water alone, while carbonisation rate remains low. This might improve patient outcome as well as patient eligibility for hyperthermic ablation.

Survival after combined resection and ablation is not inferior to that after resection alone, in patients with four or more colorectal liver metastases

PURPOSE

Colorectal liver metastases (CRLM) are the predominant factor limiting survival in patients with colorectal cancer. Multimodal treatment strategies are frequently necessary to achieve total tumor elimination. This study examines the efficacy of liver resection combined with local ablative therapy in comparison to liver resection only, in the treatment of patients with ≥ 4 CRLM.

METHODS

This retrospective cohort study was conducted at the University Hospital RWTH Aachen, Germany. Patients with ≥ 4 CRLM in preoperative imaging, who underwent curative resection between 2010-2021, were included. Recurrent resections and deaths in the early postoperative phase were excluded. Ablation modalities included radiofrequency or microwave ablation, and irreversible electroporation. Differences in overall- (OS) and recurrence-free-survival (RFS) between patients undergoing combined resection-ablation vs. resection only, were examined.

RESULTS

Of 178 included patients, 46 (27%) underwent combined resection-ablation and 132 (73%) resection only. Apart from increased rates of adjuvant chemotherapy in the first group (44% vs. 25%, p = 0.014), there were no differences in perioperative systemic therapy. Kaplan-Meier and log-rank test analyses showed no statistically significant differences in median OS (36 months for both, p = 0.638) or RFS (9 months for combined resection-ablation vs. 8 months, p = 0.921). Cox regression analysis showed a hazard ratio of 0.891 (p = 0.642) for OS and 0.981 (p = 0.924) for RFS, for patients undergoing resection only.

CONCLUSION

For patients with ≥ 4 CRLM, combined resection-ablation is a viable option in terms of OS and RFS. Therefore, combined resection-ablation should be considered for complete tumor clearance, in patients with multifocal disease.

Interventional radiological therapies in colorectal hepatic metastases

Colorectal malignancy is the third most common cancer and one of the prevalent causes of death globally. Around 20-25% of patients present with metastases at the time of diagnosis, and 50-60% of patients develop metastases in due course of the disease. Liver, followed by lung and lymph nodes, are the most common sites of colorectal cancer metastases. In such patients, the 5-year survival rate is approximately 19.2%. Although surgical resection is the primary mode of managing colorectal cancer metastases, only 10-25% of patients are competent for curative therapy. Hepatic insufficiency may be the aftermath of extensive surgical hepatectomy. Hence formal assessment of future liver remnant volume (FLR) is imperative prior to surgery to prevent hepatic failure. The evolution of minimally invasive interventional radiological techniques has enhanced the treatment algorithm of patients with colorectal cancer metastases. Studies have demonstrated that these techniques may address the limitations of curative resection, such as insufficient FLR, bi-lobar disease, and patients at higher risk for surgery. This review focuses on curative and palliative role through procedures including portal vein embolization, radioembolization, and ablation. Alongside, we deliberate various studies on conventional chemoembolization and chemoembolization with irinotecan-loaded drug-eluting beads. The radioembolization with Yttrium-90 microspheres has evolved as salvage therapy in surgically unresectable and chemo-resistant metastases.

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

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

Surgical Resection plus Intraoperative Radiofrequency Ablation versus Chemoembolization for the Treatment of Intermediate-Stage (BCLC B) Hepatocellular Carcinoma with Preserved Liver Function: A Propensity Score-Matched Analysis

Simple Summary

Surgical resection plus intraoperative radiofrequency ablation showed better survival outcomes than transarterial chemoembolization in selected patients with intermediate-stage hepatocellular carcinoma and Child–Pugh class A liver function. These findings suggest that surgical resection plus intraoperative radiofrequency ablation may provide an opportunity for curative treatment to selected patients deemed eligible only for palliative treatment.

Abstract

The purpose of this study was to compare the efficacy and safety of surgical resection (SR) plus intraoperative radiofrequency ablation (IORFA) with transarterial chemoembolization (TACE) in patients with intermediate-stage HCC and Child–Pugh class A liver function. Treatment-naïve patients who received SR plus IORFA (n = 104) or TACE (n = 513) were retrospectively evaluated. Patients were subjected to a maximum 1:3 propensity score matching (PSM), yielding 95 patients who underwent SR plus IORFA and 252 who underwent TACE. Evaluation of the entire study population showed that progression-free survival (PFS) and overall survival (OS) were significantly better in the SR plus IORFA than in the TACE group. After PSM, the median PFS (18.4 vs. 15.3 months) and OS (88.6 vs. 56.2 months) were significantly longer, and OS rate significantly higher (HR: 0.65, p = 0.026), in the SR plus IORFA group than in the TACE group. Stratified Cox regression analysis and doubly robust estimation revealed that treatment type was significantly associated with both OS and PFS. Rates of major complications were similar in the SR plus IORFA and TACE groups. In conclusion, SR plus IORFA showed better survival outcomes than TACE. SR plus IORFA may provide curative treatment to patients with intermediate-stage HCC with ≤4 tumors and Child–Pugh class A.

Minimizing the risk of small-for-size syndrome after liver surgery

BACKGROUND

Primary and secondary liver tumors are not always amenable to resection due to location and size. Inadequate future liver remnant (FLR) may prevent patients from having a curative resection or may result in increased postoperative morbidity and mortality from complications related to small-for-size syndrome (SFSS).

DATA SOURCES

This comprehensive review analyzed the principles, mechanism and risk factors associated with SFSS and presented current available options in the evaluation of FLR when planning liver surgery. In addition, it provided a detailed description of specific modalities that can be used before, during or after surgery, in order to optimize the conditions for a safe resection and minimize the risk of SFSS.

RESULTS

Several methods which aim to reduce tumor burden, preserve healthy liver parenchyma, induce hypertrophy of FLR or prevent postoperative complications help minimize the risk of SFSS.

CONCLUSIONS

With those techniques the indications of radical treatment for patients with liver tumors have significantly expanded. The successful outcome depends on appropriate patient selection, the individualization and modification of interventions and the right timing of surgery.

Contemporary evidence on colorectal liver metastases ablation: toward a paradigm shift in locoregional treatment

Image-guided percutaneous ablation techniques represent an attractive local therapy for the treatment of colorectal liver metastases (CLM) given its low risk of severe complications, which allows for early initiation of adjuvant therapies and spare functional liver parenchyma, allowing repeated treatments at the time of recurrence. However, ablation does not consistently achieve similar oncological outcomes to surgery, with the latter being currently considered the first-line local treatment modality in international guidelines. Recent application of computer-assisted ablation planning, guidance, and intra-procedural response assessment has improved percutaneous ablation outcomes. In addition, the evolving understanding of tumor molecular profiling has brought to light several biological factors associated with oncological outcomes following local therapies. The standardization of ablation procedures, the understanding of previously unknown biological factors affecting ablation outcomes, and the evidence by ongoing prospective clinical trials are poised to change the current perspective and indications on the use of ablation for CLM.

Image-Guided Ablation for Colorectal Liver Metastasis: Principles, Current Evidence, and the Path Forward

Image-guided ablation can provide effective local tumor control in selected patients with CLM. A randomized controlled trial suggested that radiofrequency ablation combined with systemic chemotherapy resulted in a survival benefit for patients with unresectable CLM, compared to systemic chemotherapy alone. For small tumors, ablation with adequate margins can be considered as an alternative to resection. The improvement of ablation technologies can allow the treatment of tumors close to major vascular structures or bile ducts, on which the applicability of thermal ablation modalities is challenging. Several factors affect the outcomes of ablation, including but not limited to tumor size, number, location, minimal ablation margin, RAS mutation status, prior hepatectomy, and extrahepatic disease. Further understanding of the impact of tumor biology and advanced imaging guidance on overall patient outcomes might help to tailor its application, and improve outcomes of image-guided ablation.

Hospital variation in combined liver resection and thermal ablation for colorectal liver metastases and impact on short-term postoperative outcomes: a nationwide population-based study

BACKGROUND

Combining resection and thermal ablation can improve short-term postoperative outcomes in patients with colorectal liver metastases (CRLM). This study assessed nationwide hospital variation and short-term postoperative outcomes after combined resection and ablation.

METHODS

In this population-based study, all CRLM patients who underwent resection in the Netherlands between 2014 and 2018 were included. After propensity score matching for age, ASA-score, Charlson-score, diameter of largest CRLM, number of CRLM and earlier resection, postoperative outcomes were compared. Postoperative complicated course (PCC) was defined as discharge after 14 days or a major complication or death within 30 days of surgery.

RESULTS

Of 4639 included patients, 3697 (80%) underwent resection and 942 (20%) resection and ablation. Unadjusted percentage of patients who underwent resection and ablation per hospital ranged between 4 and 44%. Hospital variation persisted after case-mix correction. After matching, 734 patients remained in each group. Hospital stay (median 6 vs. 7 days, p = 0.011), PCC (11% vs. 14.7%, p = 0.043) and 30-day mortality (0.7% vs. 2.3%, p = 0.018) were lower in the resection and ablation group. Differences faded in multivariable logistic regression due to inclusion of major hepatectomy.

CONCLUSION

Significant hospital variation was observed in the Netherlands. Short-term postoperative outcomes were better after combined resection and ablation, attributed to avoiding complications associated with major hepatectomy.

Effects of the proximity of metastasis to the central vessels of the liver on surgical outcomes and survival in colorectal cancer with liver metastasis

BACKGROUND

Resectability of liver metastasis is important to establish a treatment strategy for patients with colorectal cancer. We aimed to evaluate the effect of the distance from metastasis to the centre of the liver on surgical outcomes and survival after hepatectomy.

METHODS

The clinical data of a total of 155 patients who underwent hepatectomy for colorectal cancer with liver metastasis were retrospectively reviewed. We measured the minimal length from metastasis to the bifurcation of the portal vein at the primary branch of the Glissonean tree and defined it as 'centrality'. The postoperative outcomes and survival among the patients were then analysed.

RESULTS

Anatomic resections were more frequently performed, and the operative time was longer in the patients with high centrality (≤1.5 cm) than in the patients with low centrality (>1.5 cm). A size of ≥5 cm for the largest lesion, a number of lesions of ≥3 and centrality of ≤1.5 cm were found to be the independent risk factors of a positive resection margin after hepatectomy. The patients with high centrality showed worse recurrence-free survival than those with low centrality; however, there was no significant difference found in the overall survival. In the multivariate analysis, high centrality was not found to be associated with worse recurrence-free and overall survival.

CONCLUSION

Centrality significantly affected the surgical outcomes and treatment strategy for liver metastasis but did not influence the survival of the patients with colorectal cancer. Active efforts through surgical resections are important to treat liver metastasis of high centrality.

Fast and Selective Ablation of Liver Tumors by High-Intensity Focused Ultrasound Using a Toroidal Transducer Guided by Ultrasound Imaging: The Results of Animal Experiments

This study demonstrated that high-intensity focused ultrasound (HIFU) produced with an intra-operative toroidal-shaped transducer causes fast, selective liver tumor ablations in an animal model. The HIFU device is composed of 256 emitters working at 3 MHz. A 7.5 MHz ultrasound imaging probe centered on the HIFU transducer guided treatment. VX2 tumor segments (25 mg) were implanted into the right lateral liver lobes of 45 New Zealand rabbits. The animals were evenly divided into groups 1 (toroidal HIFU ablation), 2 (surgical resection) and 3 (untreated control). Therapeutic responses were evaluated with gross pathology and histology 11 d post-treatment. Toroidal transducer-produced HIFU ablation (average ablation rate 10.5 cc/min) allowed fast and homogeneous tumor treatment. Sonograms showed all ablations. VX2 tumors were completely coagulated and surrounded by safety margins without surrounding-organ secondary HIFU lesions. HIFU group tumor volumes at autopsy (39 mm³) were significantly lower than control group volumes (2610 mm³, p < 0.0001). HIFU group tumor metastasis (27%) was lower than resected (33%) and control (67%) group metastasis. Ultrasound imaging, gross pathology and histology results supported these outcomes. HIFU procedures had no complications. Rabbit liver tumor ablation using a toroidal HIFU transducer under ultrasound imaging guidance might therefore be an effective intra-operative treatment for localized liver metastases.

MRI-guided percutaneous thermoablation in combination with hepatic resection as parenchyma-sparing approach in patients with primary and secondary hepatic malignancies: single center long-term experience

BACKGROUND

Combination therapy using hepatic resection (HR) and intra-operative thermal ablation is a treatment approach for patients with technically unresectable liver malignancies. The aim of this study was to investigate safety, survival and local recurrence rates for patients with technically unresectable liver tumors undergoing HR and separate percutaneous MR-guided thermoablation procedure as an alternative approach.

METHODS

Data from all patients with primary or secondary hepatic malignancies treated at a single institution between 2004 and 2018 with combined HR and MR-guided percutaneous thermoablation was collected and retrospectively analyzed. Complications, procedure related information and patient characteristics were collected from institutional records. Overall survival and disease-free survival were estimated using the Kaplan-Meier method.

RESULTS

A total of 31 patients (age: 62.8 ± 9.1 years; 10 female) with hepatocellular carcinoma (HCC; n = 7) or hepatic metastases (n = 24) were treated for 98 hepatic tumors. Fifty-six tumors (mean diameter 28.7 ± 23.0 mm) were resected. Forty-two tumors (15.1 ± 7.6 mm) were treated with MR-guided percutaneous ablation with a technical success rate of 100%. Local recurrence at the ablation site occurred in 7 cases (22.6%); none of these was an isolated local recurrence. Six of 17 patients (35.3%) treated for colorectal liver metastases developed local recurrence. Five patients developed recurrence at the resection site (16.1%). Non-local hepatic recurrence was observed in 18 cases (58.1%) and extrahepatic recurrence in 11 cases (35.5%) during follow-up (43.1 ± 26.4 months). Ten patients (32.3%) developed complications after HR requiring pharmacological or interventional treatment. No complication requiring therapy was observed after ablation. Median survival time was 44.0 ± 7.5 months with 1-,3-, 5-year overall survival rates of 93.5, 68.7 and 31.9%, respectively. The 1-, 3- and 5-year disease-free survival rates were 38.7, 19.4 and 9.7%, respectively.

CONCLUSION

The combination of HR and MR-guided thermoablation is a safe and effective approach in the treatment of technically unresectable hepatic tumors and can achieve long-term survival.

Clinical analysis of ultrasound-guided radiofrequency ablation for recurrent colorectal liver metastases after hepatectomy

Background

RFA is designed to produce localized tumor destruction by heating the tumor and surrounding liver tissue, especially suitable for patients who do not qualify for hepatic resection. Many studies have reported that RFA was inferior to hepatectomy in the treatment of recurrent colorectal liver metastases. However, strong evidence is lacking in the literature. This study aimed to investigate the effect and clinical outcome of percutaneous ultrasound-guided RFA and repeat hepatic resection for recurrent colorectal liver metastases after hepatectomy.

Methods

From January 2007 to January 2014, 194 patients with recurrent colorectal liver metastases after hepatectomy diagnosed in our hospital was performed, and then divided into two groups based on different regimens: repeat hepatic resection group and RFA group. The clinical data of the two groups were analyzed. After treatment, the liver function-related indexes, complication rate, survival rate, and tumor recurrence of the two groups were recorded. The difference in short-term and long-term effects between repeat hepatic resection and RFA was identified by propensity score analysis.

Results

The number of metastases and the proportion of left and right lobe involved by tumor and preoperative chemotherapy in the RFA group were higher than those in the repeat hepatic resection group. The clinical data showed no significant difference between the two groups after using propensity score analysis. Compared with the RFA group, the liver function of the repeat hepatic resection group was significantly improved. After adjustment for potential confounders, no significant difference in liver function-related indexes was found between RFA and repeat hepatic resection, and the incidence of complications in the RFA group was lower. In survival analysis, there was no significant difference in OS and DFS between the two groups.

Conclusions

RFA is a safe and effective therapeutic option for patients with recurrent colorectal liver metastases after hepatectomy.

Hepatic Ablation Promotes Colon Cancer Metastases in an Immunocompetent Murine Model

OBJECTIVE

To determine the impact of radiofrequency (RF) and microwave (MW) energy compared to direct cautery on metatstatic colon cancer growth.

BACKGROUND

Hepatic ablation with MW and RF energy creates a temperature gradient around a target site with temperatures known to create tissue injury and cell death. In contrast, direct heat application (cautery) vaporizes tissue with a higher site temperature but reduced heat gradient on surrounding tissue. We hypothesize that different energy devices create variable zones of sublethal injury that may promote tumor recurrence. To test this hypothesis we applied MW, RF, and cautery to normal murine liver with a concomitant metastatic colon cancer challenge.

METHODS

C57/Bl6 mice received hepatic thermal injury with MW, RF, or cautery to create a superficial 3-mm lesion immediately after intrasplenic injection of 50K MC38 colon cancer cells. Thermal imaging recorded tissue temperature during ablation and for 10 seconds after energy cessation. Hepatic tumor location and volume was determined at day 7.

RESULTS

Cautery demonstrated the highest maximum tissue temperatures (129°C) with more rapid return to baseline compared to MW or RF energy. All mice had metastasis at the ablation site. Mean tumor volume was significantly greater in the MW (95.3 mm; P = 0.007) and RF (55.7 mm; P = 0.015) than cautery (7.13 mm). There was no difference in volume between MW and RF energy (P = 0.2).

CONCLUSIONS

Hepatic thermal ablation promotes colon cancer metastasis at the injury site. MV and RF energy result in greater metastatic volume than cautery. These data suggest that the method of energy delivery promotes local metastasis.

CAN MICROWAVE ABLATION BE AN ALTERNATIVE TO RESECTION FOR THE TREATMENT OF NEUROENDOCRINE LIVER METASTASES?

Objective: Surgical resection of neuroendocrine tumor liver metastases has been proven to improve survival, but the benefit of microwave ablation as an alternative or adjunct to surgery has yet to be assessed. Our hypothesis is that ablation is equal to surgery in terms of local recurrence and survival. Methods: We conducted a retrospective analysis including all patients treated with microwave ablation and/or surgical resection for neuroendocrine liver metastases in our institution between 2008 and 2017. Results: A total of 47 patients and 68 treatments were analyzed, including 34 liver resections, 20 ablations, and 14 combined procedures. A total of 130 individual metastases were treated with ablation, representing a median of 4 per session (range 1-30). While no major complications occurred after ablation, we observed 11 minor and 3 major complications after open surgical resection (P = .0135). Length of stay was significantly shorter after ablation (P = .0008). The majority of patients (33/47, 70.2%) underwent curative procedures, 14 patients underwent (29.8%) debulking procedures. There was no difference in local recurrence rate between tumors treated with ablation or resection. Liver-only disease progression was detected in 29% of the patients and overall progression was detected in 66% of the patients. The mean survival was not significantly different between patients treated with ablation only versus resection with or without ablation (P = .1570). Overall survival was mean 75.3 months (6 to 374 months). Conclusion: Depending on the extent of the liver metastases, microwave ablation might be a safe alternative or addition to resection for neuroendocrine tumor liver metastases with low morbidity and high local efficiency. Abbreviations: CT = computed tomography; MWA = microwave ablation; NET = neuroendocrine tumor; PET = positron emission tomography; RFA = radiofrequency ablation; RFS = recurrence-free survival; SMWA = stereotactic microwave ablation.

Systematic review and meta-analysis of local ablative therapies for resectable colorectal liver metastases

INTRODUCTION

Local ablative therapies (LAT) have shown positive but heterogenous outcomes in the treatment of colorectal liver metastases (CRLM). The aim of this systematic review is to evaluate LAT and compare them with surgical resection.

METHODS

In accordance with PRISMA guidelines, Medline, EMBASE, Cochrane and Web of Science databases were searched for reports published before January 2019. We included papers assessing radiofrequency ablation (RFA), microwave ablation (MWA), cryoablation (CA) and electroporation (IRE) treating resectable CRLM with curative intention. We evaluated LAT related complications and oncological outcomes as tumour progression (LTP), disease-free survival (DFS) and overall survival (OS).

RESULTS

The literature search yielded 6767 records; 20 papers (860 patients) were included. No included studies related mortality with LAT. Median adverse events percentage was 7%: (8% RFA;7% MWA). Median 3y-DFS was 32% (24% RFA; 60% MWA); 5y-DFS was 27%: (18% RFA; 38.5% MWA). Median 3y-OS was 59% (60% RFA; 70% MWA; 34% CA), 5y-OS was 44.5% (43% RFA; 55% MWA; 20% CA). Surgical resection showed decreased LTP, improved DFS and OS than those reported with LAT, with RFA accounting for reduced 1y-DFS (RR 0.83, 95%CI 0.71-0.98), 3y-DFS (RR 0.5, 95%CI 0.33-0.76), 5y-DFS (RR 0.53, 95%CI 0.28-0.98) and 5y-OS (RR 0.76, 95%CI 0.58-0.98) in comparison with surgical resection.

CONCLUSIONS

Low quality evidence suggests that both RFA and MWA seem superior to CA. MWA presents similar adverse events when compared to RFA with a possible increase in DFS and OS. Surgical resection still seems to provide superior DFS and OS in comparison with LAT.

Pan-Asian adapted ESMO consensus guidelines for the management of patients with metastatic colorectal cancer: a JSMO-ESMO initiative endorsed by CSCO, KACO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) consensus guidelines for the treatment of patients with metastatic colorectal cancer (mCRC) was published in 2016, identifying both a more strategic approach to the administration of the available systemic therapy choices, and a greater emphasis on the use of ablative techniques, including surgery. At the 2016 ESMO Asia Meeting, in December 2016, it was decided by both ESMO and the Japanese Society of Medical Oncology (JSMO) to convene a special guidelines meeting, endorsed by both ESMO and JSMO, immediately after the JSMO 2017 Annual Meeting. The aim was to adapt the ESMO consensus guidelines to take into account the ethnic differences relating to the toxicity as well as other aspects of certain systemic treatments in patients of Asian ethnicity. These guidelines represent the consensus opinions reached by experts in the treatment of patients with mCRC identified by the Presidents of the oncological societies of Japan (JSMO), China (Chinese Society of Clinical Oncology), Korea (Korean Association for Clinical Oncology), Malaysia (Malaysian Oncological Society), Singapore (Singapore Society of Oncology) and Taiwan (Taiwan Oncology Society). The voting was based on scientific evidence and was independent of both the current treatment practices and the drug availability and reimbursement situations in the individual participating Asian countries.

Local treatment of liver and lung metastases from colorectal cancer: a multicenter Tunisian study

Aim: Surgical treatment of hepatic or pulmonary metastases is the optimal therapeutic goal in metastatic colorectal cancer (CRC). Methods: Our retrospective study concerned 70 patients treated for CRC, collected from 2003 to 2015, presenting liver metastases (LM) in 61 cases and pulmonary metastases (PM) in nine cases, treated by surgery for their distant disease. We collected and compared their epidemiologic, anatomoclinical parameters and analyzed several prognostic factors. Results: Metastases were multiple (≥ 4) in 9/61 LM and in 5/9 PM. Patients had synchronous metastases in 32 cases (30 LM/2 PM) and metachronous metastases in 33 cases (32 LM and 11 PM). Surgery for LM consisted of metastasectomy (49/61), segmentectomy (5/61) and hepatectomy for the remaining seven patients; ten patients had also subsequent liver radiofrequency. LM were treated by wedge resection in 6/9 and lobectomy in two cases, radiofrequency was performed in five cases. 56/61 (80%) patients received chemotherapy, mostly FOLFOX protocol as the first-line treatment and targeted therapy in 55% of cases. For the overall population, median OS and PFS were, respectively, 44 and 32 months. We did not observe any significant difference in terms of OS (p = 0.659) and PFS (p = 0.318) between resected LM or/and PM. A better survival was found when there was disease-free interval between the occurrence of the primary and the metastases exceeded 18 months and in patients with less than four metastases. Conclusion: Resection of metastatic disease mostly in liver and lungs improves survival of patients with CRC. The patients with longer disease-free interval and less than four metastases had the best outcomes.

Surgical resection plus radiofrequency ablation for the treatment of multifocal hepatocellular carcinoma

Background

To compare the efficacy and safety of surgical resection plus radiofrequency ablation (SR-RFA) with transarterial chemoembolization (TACE) in patients with multifocal hepatocellular carcinoma (HCC) beyond the Milan criteria.

Methods

From 2009 to 2015, a total of 469 consecutive patients with multifocal HCC beyond the Milan criteria (≤5 nodules) treated with SR-RFA (n=59) or TACE (n=410) were analyzed. Their overall survival (OS) rate was compared through propensity score matching (PSM) analysis at a ratio of 1:2, and 141 patients were identified (SR-RFA, n=47; TACE, n=94). Subgroup analysis was conducted according to factors associated with treatment options.

Results

Before PSM, the 1-, 2- and 3-year OS rates were 81.5%, 68.3% and 64.3% in the SR-RFA group and 58.7%, 35.5% and 24.4% in the TACE group, respectively (all P<0.001). After PSM, the 1-, 2- and 3-year OS rates in the SR-RFA group were 81.8%, 68.7% and 63.4%, whereas those in the TACE group were 59.3%, 36.1% and 19.4%, respectively (all P<0.001). Subgroup analysis also revealed a survival advantage of SR-RFA over TACE in each subgroup. The 30-day mortality rate was 1.22% in the TACE group and nil in the SR-RFA group (P=0.861).

Conclusions

SR-RFA provides better a long-term survival rate than TACE for patients with multifocal HCC beyond the Milan criteria. SR-RFA may serve as an alternative treatment for patients with multifocal HCC in a selected patient population.

Living donor liver transplantation with two-stage hepatectomy for patients with isolated, irresectable colorectal liver-the LIVER-T(W)O-HEAL study

BACKGROUND

Colorectal cancer is the third most common malignancy worldwide. The occurrence of liver metastases worsens the prognosis of the patient significantly if the tumor burden is not resectable. Liver transplantation might be an option for otherwise irresectable colorectal liver metastases. In this study, we evaluate the role of two-stage hepatectomy in combination with a left-lateral living donor liver transplantation.

METHODS

Patients with irresectable liver metastases having a stable disease or tumor regression after at least 8 weeks of systemic chemotherapy without an extrahepatic tumor burden (except resectable lung metastases) are suitable for study inclusion. A randomization is not planned since the control arm (systemic chemotherapy) is well established and the superiority of the transplantation procedure has to be expected. The surgical treatment consists of two steps: in a first operation, a left hemihepatectomy in the recipient will be performed. At this place, the left lateral liver lobe (segments II and III) of a living donor will be transplanted. To induce a growth of the graft, a portal vein ligation will be performed. Approximately after 2 weeks, the removal of the right hemiliver will be conducted if the control imaging shows a sufficient growth of the graft.

RESULTS

The patient recruitment is ongoing. In total, three patients have been already transplanted with this protocol. Up to now, they are tumor-free and in good clinical health.

DISCUSSION

With the design of the LIVER-T(W)O-HEAL study, it might be possible to offer patients with otherwise irresectable colorectal liver metastases a curative treatment option. The key point of this study will be, most probably, the patient's selection.

TRIAL REGISTRATION

Registered at Clinical Trials; NCT03488953 ; registered on April 5, 2018.

Meta-Analysis of Long-Term Outcomes in Patients with Colorectal Liver Metastases Undergoing Hepatectomy with or without Radiofrequency Ablation

This meta-analysis aimed to compare the long-term prognosis of patients with colorectal liver metastases undergoing liver resection (LR) with or without radiofrequency ablation (RFA). A systematic search was performed using both medical subject headings and truncated word searches to identify all comparative studies published on this topic. The primary outcomes were postoperative overall survival (OS) and disease-free survival (DFS). Pooled hazard ratios (HR) with 95 per cent confidence intervals (95% CI) were calculated. A total of 10 studies which included 3900 patients were finally enrolled in the meta-analysis. Patients treated by LR gained better OS (HR: 2.07, 95% CI: 1.82–2.37) and DFS (HR: 1.91, 95% CI: 1.70–2.15) than those patients treated by LR 1 RFA, after pooling unadjusted HRs from the 10 studies. Five studies provided the data of adjusted HR. The pooled results showed that patients in the LR 1 RFA group had shorter OS (HR: 1.66, 95% CI: 1.18–2.32, P = 0.004) but similar DFS (HR: 1.36, 95% CI: 0.99–1.88) compared with patients in the LR group. Our meta-analysis showed that colorectal liver metastases patients who underwent LR gained better long-term outcomes compared with patients undergoing LR 1 RFA. However, after adjusting confounders, LR 1 RFA achieved comparable DFS with LR alone.

Repeating of local therapy of distant metastases increases overall survival in patients with synchronous metastasized rectal cancer-a monocentric analysis

PURPOSE

The aim was to evaluate the outcome of treatment-naive patients with synchronous metastatic rectal cancer after chemotherapy with FOLFOXIRI followed by local therapeutic procedures of all tumor lesions as complete as possible.

METHODS

We reviewed data of 30 patients with synchronous distant metastatic rectal cancer who underwent chemotherapy with FOLFOXIRI and subsequent local therapy in our institution.

RESULTS

Median follow-up was 28 months (range: 8; 74). Cumulative overall survival (OS) and progression-free survival (PFS) was 93.3, 76.9, 55.6% and 46.2, 29.7, 29.7% after 1, 2, 4 years. Non-response to chemotherapy with FOLFOXIRI was associated with a highly significant decreased OS (p < 0.0001). The consistent use of local ablative procedures led to a statistically significant increase in OS (p < 0.0001), but not in PFS (p = 0.635). Patients with ≤ 4 distant metastases showed a better OS (p = 0.033).

CONCLUSIONS

Response to intensified first-line chemotherapy with FOLFOXIRI, treatment of the primary rectal tumor, and repeated thorough local ablative procedures in patients with synchronous metastasized rectal cancer may lead to long-term survival, even in a subset of patients with unresectable disease at initial diagnosis.

Feasibility, efficacy, and safety of percutaneous MR-guided ablation of small (≤12 mm) hepatic malignancies

BACKGROUND

Percutaneous tumor ablation is commonly performed using computed tomography (CT) or ultrasound (US) guidance, although reliable visualization of the target tumor may be challenging. MRI guidance provides more reliable visualization of target tumors and allows for real-time imaging and multiplanar capabilities, making it the modality of choice, in particular if lesions are small.

PURPOSE

To investigate the feasibility, technical success, and safety of percutaneous MR-guided ablation (RFA n = 27 / MWA n = 16) of small (≤12 mm) hepatic malignancies.

STUDY TYPE

Retrospective case study.

POPULATION

In all, 45 patients (age: 61.1 ± 11.8) with hepatic malignancies and a lesion diameter of ≤12 mm scheduled for percutaneous MR-guided tumor ablation based on a tumor board decision were included.

FIELD STRENGTH

A 1.5T MR system was used for planning, targeting, and monitoring.

ASSESSMENT

Feasibility assessment included the detection of the target tumor, tumor delineation during MR-fluoroscopy guided targeting, and the number of attempts needed for precise applicator placement. Technical success was defined as successful performance of the procedure including a safety margin of 5 mm. Safety evaluation was based on procedure-related complications.

STATISTICAL TEST

Frequency.

RESULTS

Tumor ablation (mean diameter 9.0 ± 2.1 mm) was successfully completed in 43/45 patients. Planning imaging was conducted without a contrast agent in 79% (n = 37). In 64% (n = 30), the target tumors were visible with MR-fluoroscopy. In six patients (13%), planning imaging revealed new, unexpected small lesions, which were either treated in the same session (n = 4) or changed therapy management (n = 2) due to diffuse tumor progress. Postprocedural imaging revealed a technical success of 100% (43/43), with no major complications. During follow-up, no local tumor progression was observed (mean follow-up 24.7 ± 14.0 months) although 28% (12) patients developed new hepatic lesions distant to the ablation zone. No major complications were observed.

DATA CONCLUSION

MR-guided ablation is a feasible approach for an effective and safe treatment of small hepatic malignancies.

LEVEL OF EVIDENCE

4 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2019;49:374-381.

Radiofrequency and Microwave Ablation Compared to Systemic Chemotherapy and to Partial Hepatectomy in the Treatment of Colorectal Liver Metastases: A Systematic Review and Meta-Analysis

Purpose

To assess safety and outcome of radiofrequency ablation (RFA) and microwave ablation (MWA) as compared to systemic chemotherapy and partial hepatectomy (PH) in the treatment of colorectal liver metastases (CRLM).

Methods

MEDLINE, Embase and the Cochrane Library were searched. Randomized trials and comparative observational studies with multivariate analysis and/or matching were included. Guidelines from National Guideline Clearinghouse and Guidelines International Network were assessed using the AGREE II instrument.

Results

The search revealed 3530 records; 328 were selected for full-text review; 48 were included: 8 systematic reviews, 2 randomized studies, 26 comparative observational studies, 2 guideline-articles and 10 case series; in addition 13 guidelines were evaluated. Literature to assess the effectiveness of ablation was limited. RFA + systemic chemotherapy was superior to chemotherapy alone. PH was superior to RFA alone but not to RFA + PH or to MWA. Compared to PH, RFA showed fewer complications, MWA did not. Outcomes were subject to residual confounding since ablation was only employed for unresectable disease.

Conclusion

The results from the EORTC-CLOCC trial, the comparable survival for ablation + PH versus PH alone, the potential to induce long-term disease control and the low complication rate argue in favour of ablation over chemotherapy alone. Further randomized comparisons of ablation to current-day chemotherapy alone should therefore be considered unethical. Hence, the highest achievable level of evidence for unresectable CRLM seems reached. The apparent selection bias from previous studies and the superior safety profile mandate the setup of randomized controlled trials comparing ablation to surgery.

Electronic supplementary material

The online version of this article (10.1007/s00270-018-1959-3) contains supplementary material, which is available to authorized users.

Non-response to preoperative chemotherapy is a contraindication to hepatectomy plus radiofrequency ablation in patients with colorectal liver metastases

The long-term outcome of 228 patients with colorectal liver metastases (CRLM) who underwent preoperative chemotherapy followed by hepatectomy ± RFA were retrospectively analyzed. Stratified by chemotherapy response, patients were divided into responding (n=129) and non-responding groups (n=99). Patients who underwent hepatectomy-RFA had a greater number of metastases (median of 4 vs. 2, p=0.000), a higher incidence of bilobar involvement (66.7% vs. 49.1%, p=0.014) and longer chemotherapy cycles (median of 6 vs. 4, p=0.000). In the responding group, the median overall survival (OS) and recurrence free survival (RFS) of hepatectomy-RFA and the hepatectomy alone subgroups were comparable (38.6 months vs. 43.2 months, p=0.824; 8.2 months vs. 11.4 months, p=0.623). In the non-responding group, the median OS and RFS of patients treated with hepatectomy-RFA were significantly shorter (18.5 months vs. 34.2 months, p=0.000; 5.1 months vs. 5.9 months, p=0.002). RFA was identified as the unfavorable independent factor for both OS (HR=3.60, 95%CI=1.81-7.16, p=0.039) and RFS (HR=1.70, 95%CI=1.00-2.86, p=0.048) in non-responsive patients. Local recurrence rate after hepatectomy-RFA was higher in the non-responding group (48.1% vs. 23.6%, p=0.018). Non-response to preoperative chemotherapy may be a contraindication to hepatectomy-RFA in patients with CRLM.