Outcomes of microwave ablation for colorectal cancer liver metastases: a single center experience

Gamma-glutamyl transferase to aspartate aminotransferase ratio (GSR) predicts prognoses in patients with colorectal cancer with liver metastasis after microwave ablation

BACKGROUND

Microwave ablation (MWA) is widely used to eliminate colorectal liver metastases (CRLM). However, the risk of tumor recurrence is difficult to predict due to lack of reliable clinical and biological markers. Elevation of gamma-glutamyl transferase (GGT) and aspartate transaminase (AST) provides signals for liver inflammation and cancer progression. The present study evaluated the association between pre-ablation GGT to AST ratio index (GSR) and hepatic recurrence in patients with CRLM after MWA.

METHODS

A retrospectively analyzed 192 CRLM patients who underwent MWA from January 2013 to December 2017. Pre-ablation GSR was classified into high (≤ 2.34) or low (> 2.34) using the upper quartile value. The prognostic value of GSR and other risk factors for liver progression-free survival (LPFS) and cancer-specific survival (CSS) were evaluated by univariate and multivariate analyses.

RESULTS

High GSR was significantly associated with males (P = 0.041), the presence of cholelithiasis (P = 0.012), but not pre-ablation chemotherapy (P = 0.355), which caused significantly increased levels of GGT (P = 0.015) and AST (P = 0.008). GSR showed a significant association with LPFS and CSS through univariate analysis (P = 0.002 and 0.006) and multivariate analysis (P = 0.043 and 0.037). The subgroup analysis demonstrated no interaction between GSR and all variables except for distribution in the sub-analysis of LPFS.

CONCLUSIONS

Our findings suggest that the pre-ablation GSR can be considered as a promising prognostic indicator for poor prognosis of patients with CRLM underwent MWA.

TRIAL REGISTRATION

Not applicable.

Microwave ablation for colorectal liver metastases with ultrasound fusion imaging assistance: a stratified analysis study based on tumor size and location

PURPOSE

To investigate the efficacy of ultrasound fusion imaging-assisted microwave ablation (MWA) for patients with colorectal liver metastases (CRLM) based on stratified analysis of tumor size and location.

METHODS

Patients with CRLM who underwent ultrasound fusion imaging-assisted MWA in our hospital between February 2020 and February 2023 were enrolled into this retrospective study. Ultrasound fusion imaging was used for detection, guidance, monitoring and immediate evaluation throughout the MWA procedures. Technical success, technique efficacy, local tumor progression (LTP), intrahepatic progression and overall survival (OS) were recorded and analyzed. The subgroup analysis of intrahepatic progression of MWA for CRLM was performed according to tumor size and location.

RESULTS

A total of 51 patients with 122 nodules were enrolled. Both technical success and technique efficacy were acquired in all nodules. In a median follow-up period of 19 months, 2.5% of the nodules (3/122) were observed LTP. The 1-year and 2-year cumulative intrahepatic progression rates were 38.7% and 52.1% respectively. Patients were divided into subgroups according to tumor size (≥ 30 mm, n = 13; < 30 mm, n = 38) and tumor location (perivascular, n = 20; non-perivascular, n = 31 and subcapsular, n = 36; non-subcapsular, n = 15). The cumulative intrahepatic progression rates were similar between the subgroups regarding tumor size and perivascular location, while significantly higher in the subcapsular group than in the non-subcapsular group (p = 0.021).

CONCLUSION

Ultrasound fusion imaging-assisted MWA exhibited satisfactory local efficacy for CRLM, especially for non-subcapsular tumors.

HPB ultrasound guidance techniques - Targeting

Ultrasound is an indispensable tool for intraoperative assessment and treatment of hepatopancreatobiliary pathology. As minimally invasive approaches to HPB surgery continue to expand and the benefits of parenchymal-sparing liver surgery are increasingly appreciated, skillful targeting will play an even bigger role in HPB surgical practice. Techniques for intraoperative targeting of liver lesions for the purposes of biopsy and ablation, particularly in the laparoscopic setting, are the focus of this chapter. Current evidence supports the use of ablation for a variety of liver lesions including hepatocellular carcinoma and metastatic colorectal cancer, particularly for smaller lesions. Successful targeting requires optimization of patient position and port placement. When targeting multiple lesions, thoughtful treatment sequencing is critical to maintaining visualization and optimizing outcomes.

Recurrence patterns after complex multimodality therapy and hepatic arterial infusion for colorectal liver metastases: A reflection of biology and technique

BACKGROUND AND METHODS

We characterized colorectal liver metastasis recurrence and survival patterns after surgical resection and intraoperative ablation ± hepatic arterial infusion pump (HAIP) placement. We estimated patterns of recurrence and survival in patients undergoing contemporary multimodal treatments. Between 2017 and 2021, patient, tumor characteristics, and recurrence data were collected. Primary outcomes included recurrence patterns and survival data based on operative intervention.

RESULTS

There were 184 patients who underwent hepatectomy and intraoperative ablation. Sixty patients (32.6%) underwent HAIP placement. A total of 513 metastases were ablated, median total of 2 ablations per patient. Median time to recurrence was 31 [22-40] months. Recurrence patterns included tumor at ablative margin on first scheduled postoperative imaging (8, 4.3%), local tumor recurrence at ablative site (69, 37.5%), and non-ablated liver tumor recurrence (38, 20.6%). In patients who underwent HAIP placement, the rate of liver recurrence was reduced (45% vs 70.9%, p = 0.0001). Median overall survival was 64 [41-58] months and prolonged survival was associated with HAIP treatment (85 [66-109] vs 60 [51-70] months.

CONCLUSIONS AND DISCUSSION

Hepatic recurrence is common and combination of intraoperative ablation and HAIP treatments were associated with prolonged survival. These data may reflect patient selection however, future work will clarify preoperative tumor and patient characteristics that may better predict recurrence expectations.

Unresectable Intermediate-Size (3-5 cm) Colorectal Liver Metastases: Stereotactic Ablative Body Radiotherapy Versus Microwave Ablation (COLLISION-XL): Protocol of a Phase II/III Multicentre Randomized Controlled Trial

BACKGROUND

Although microwave ablation (MWA) has a low complication rate and good efficacy for small-size (≤ 3 cm) colorectal liver metastases (CRLM), local control decreases with increasing size. Stereotactic body radiotherapy (SBRT) is gaining interest as a potential means to treat intermediate-size CRLM and might be less susceptible to increasing volume. The objective of this study is to compare the efficacy of MWA to SBRT in patients with unresectable, intermediate-size (3-5 cm) CRLM.

METHODS

In this two-arm, multicentre phase II/ III randomized controlled trial, 68 patients with 1-3 unresectable, intermediate-size CRLM suitable for both MWA and SBRT, will be included. Patients will be treated with MWA or SBRT as randomised. The Primary endpoint is local tumour progression-free survival (LTPFS) at 1 year (intention-to-treat analysis). Main secondary endpoints are overall survival, overall and distant progression-free survival (DPFS), local control (LC) and procedural morbidity and mortality and assessment of pain and quality of life.

DISCUSSION

Current guidelines lack clear recommendations for the local treatment of liver only intermediate-size, unresectable CRLM and studies comparing curative intent SBRT and thermal ablation are scarce. Although safety and feasibility to eradicate tumours ≤ 5 cm have been established, both techniques suffer from lower LTPFS and LC rates for larger-size tumours. For the treatment of unresectable intermediate-size CRLM clinical equipoise has been reached. We have designed a two-armed phase II/ III randomized controlled trial directly comparing SBRT to MWA for unresectable CRLM 3-5 cm.

LEVEL OF EVIDENCE

Level 1, phase II/ III Randomized controlled trial.

TRIAL REGISTRATION

NCT04081168, September 9th 2019.

Colorectal Liver Metastases: A Literature Review of Viable Surgical Options with a Special Focus on Microwave Liver Thermal Ablation and Mini-Invasive Approach

Colorectal cancer (CRC) is the third most common tumor worldwide and it is characterized in 20-30% of cases by liver involvement, which strongly affects the long-term patient outcome. There are many available therapies for liver colorectal metastases (CRLMs); the current standard of care is represented by liver resection, and when feasible, associated with systemic chemotherapy. Microwave thermal ablation (MWA) is a viable option in unresectable patients or to achieve treatment with a parenchymal spearing approach. A literature review was performed for studies published between January 2000 and July 2022 through a database search using PUBMED/Medline and the Cochrane Collaboration Library with the following MeSH search terms and keywords: microwave, ablation, liver metastases, colorectal neoplasm, and colon liver rectal metastases. The recurrence rate and overall patients' survival were evaluated, showing that laparoscopic MWA is safe and effective to treat CRLMs when resection is not feasible, or a major hepatectomy in fragile patients is necessary. Considering the low morbidity of this procedure, it is a viable option to treat patients with recurrent diseases in the era of effective chemotherapy and multimodal treatments.

Microwave Ablation, Radiofrequency Ablation, Irreversible Electroporation, and Stereotactic Ablative Body Radiotherapy for Intermediate Size (3-5 cm) Unresectable Colorectal Liver Metastases: a Systematic Review and Meta-analysis

Purpose of Review

Based on good local control rates and an excellent safety profile, guidelines consider thermal ablation the gold standard to eliminate small unresectable colorectal liver metastases (CRLM). However, efficacy decreases exponentially with increasing tumour size. The preferred treatment for intermediate-size unresectable CRLM remains uncertain. This systematic review and meta-analysis compare safety and efficacy of local ablative treatments for unresectable intermediate-size CRLM (3–5 cm).

Recent Findings

We systematically searched for publications reporting treatment outcomes of unresectable intermediate-size CRLM treated with thermal ablation, irreversible electroporation (IRE) or stereotactic ablative body-radiotherapy (SABR). No comparative studies or randomized trials were found. Literature to assess effectiveness was limited and there was substantial heterogeneity in outcomes and study populations. Per-patient local control ranged 22–90% for all techniques; 22–89% (8 series) for thermal ablation, 44% (1 series) for IRE, and 67–90% (1 series) for SABR depending on radiation dose.

Summary

Focal ablative therapy is safe and can induce long-term disease control, even for intermediate-size CRLM. Although SABR and tumuor-bracketing techniques such as IRE are suggested to be less susceptible to size, evidence to support any claims of superiority of one technique over the other is unsubstantiated by the available evidence. Future prospective comparative studies should address local-tumour-progression-free-survival, local control rate, overall survival, adverse events, and quality-of-life.

Microwave Ablation for Colorectal Liver Metastases: A Systematic Review and Pooled Oncological Analyses

Simple Summary

Liver resection for colorectal liver metastases (CRLM) represents the best curative option; however, few patients are candidates for surgery. Microwave ablation (MWA) can be a valid alternative in selected patients. This systematic review reports the oncological results of MWA for CRLM. The literature available on the Web was analyzed for reports concerning MWA for resectable CRLM, published before January 2021. Finally, 12 papers concerning MWA complications, recurrence-free (RF) cases, patients free from local recurrence (FFLR), and overall survival rates (OS) were selected. Global RF rates at 1, 3, and 5 years were 65.1%, 44.6%, and 34.3%, respectively. Global FFLR at 3, 6, and 12 months were 96.3%, 89.6%, and 83.7%, respectively. Global OS rates at 1, 3, and 5 years were 86.7%, 59.6%, and 44.8%, respectively. A better FFLR was achieved with an MWA surgical approach at 3, 6, and 12 months, with 97.1%, 92.7%, and 88.6%, respectively. Surgical MWA for CRLM smaller than 3 cm was a safe and valid option. MWA can be entered as part of the flowchart decision of CRLM curative treatment, especially for use in the parenchyma-sparing strategy and as a complement to surgery.

Abstract

(1) Background: colorectal liver metastases (CRLM) are the most common extra-lymphatic metastases in colorectal cancer; however, few patients are fit for curative surgery. Microwave ablation (MWA) showed promising outcomes in this cohort of patients. This systematic review and pooled analysis aimed to analyze the oncological results of MWA for CRLM. (2) Methods: Following PRISMA guidelines, PubMed, Scopus, EMBASE, Google Scholar, Science Direct, and the Wiley Online Library databases were searched for reports published before January 2021. We included papers assessing MWA, treating resectable CRLM with curative intention. We evaluated the reported MWA-related complications and oncological outcomes as being recurrence-free (RF), free from local recurrence (FFLR), and overall survival rates (OS). (3) Results: Twelve out of 4822 papers (395 patients) were finally included. Global RF rates at 1, 3, and 5 years were 65.1%, 44.6%, and 34.3%, respectively. Global FFLR rates at 3, 6, and 12 months were 96.3%, 89.6%, and 83.7%, respectively. Global OS at 1, 3, and 5 years were 86.7%, 59.6%, and 44.8%, respectively. A better FFLR was reached using the MWA surgical approach at 3, 6, and 12 months, with reported rates of 97.1%, 92.7%, and 88.6%, respectively. (4) Conclusions: Surgical MWA treatment for CRLM smaller than 3 cm is a safe and valid option. This approach can be safely included for selected patients in the curative intent approaches to treating CRLM.

Radiofrequency versus microwave ablation for intraoperative treatment of colorectal liver metastases

INTRODUCTION

Intraoperative radiofrequency ablation (RFA) and the newer technique of microwave ablation (MWA) can both be of additional value in parenchyma preserving surgical treatment of colorectal liver metastases (CRLM). MWA is less influenced by the heat-sink effect of surrounding vessels and can generate more heat in less time but RFA is still widely used. True comparing studies are scarce.

METHODS

This single centre retrospective cohort study analyzed patients who underwent ultrasound guided intraoperative ablation as a part of the surgical treatment of CRLM between 2013 and 2018. In September 2015, MWA was substituted for RFA. Outcomes included unsuccessful ablation rates at 1-year postoperative, 30-days major complication rates, progression free survival (PFS) and overall survival (OS). Logistic regression models were used for univariable and multivariable analyses to identify predictors of unsuccessful ablation.

RESULTS

Forty-one patients underwent RFA of 98 lesions (median 2) and 79 patients underwent MWA of 193 lesions (median 2). The median diameter of the ablated lesions was 9 mm for both RFA and MWA. Unsuccessful ablation was observed in 7 metastases (7.1%) after RFA and 14 metastases (7.3%) after MWA (p = 1.000). Complications requiring re-intervention were observed after 8 procedures, 2 complications in the RFA group (4.9%) versus 6 complications in the MWA group (7.6%, p = 0.714), of which 6 were liver-related. Ninety-day mortality did not occur. Ablation technique was not associated with unsuccessful ablations. CRLM size was associated with unsuccessful ablation in the per lesion analysis (p < 0.001).

CONCLUSION

Intraoperative RFA and MWA were equally effective for treatment of small CRLM.

Percutaneous Microwave Ablation Versus Open Surgical Resection for Colorectal Cancer Liver Metastasis

Purpose

To compare the therapeutic outcomes between open surgical resection (OSR) and percutaneous microwave ablation (PMWA) for colorectal liver metastasis (CRLM) ≤3 cm.

Methods

In this retrospective study, 200 consecutive patients with 306 CRLMs were reviewed. Overall survival (OS), disease-free survival (DFS), local tumour progression (LTP), intrahepatic distant recurrence, and extrahepatic metastasis were analysed to compare the therapeutic efficacy. Cox proportional hazards regression analysis was used to identify the prognostic factors for OS and DFS. Major complications and postoperative hospital stay were also assessed.

Result

The 1-, 3-, and 5-year OS rates were 91.6%, 64.1%, and 46.3%, respectively, in the PMWA group and 89.7%, 62.4% and 44.7%, respectively, in the OSR group (P=0.839). The 1-, 3-, and 5-year DFS rates were 61.9%, 44.8%, and 41.3%, respectively, in the PMWA group and 58.1%, 24.4%, and 18.3%, respectively, in the OSR group (P =0.066). The two groups had comparable 5-year cumulative rates of intrahepatic distant recurrence (P=0.627) and extrahepatic metastasis (P=0.884). The 5-year cumulative LTP rate was lower in the OSR group than in the PMWA group (P=0.023). The rate of major complications was higher in the OSR group than in the PMWA group (P =0.025), and the length of hospital stay after treatment was shorter in the PMWA group (P<0.001).

Conclusion

There were no significant differences in OS or DFS between the two groups. PMWA was associated with increased LTP, fewer postoperative days and fewer major complications.

Long-term results of percutaneous microwave ablation for colorectal liver metastases

BACKGROUND

Radiofrequency ablation (RFA) has been used for therapy of colorectal liver metastases (CRLMs) several years, with considerable data confirming its safety and efficacy. However, there are few studies focusing on the long-term results of percrtaneous microwave ablation (PMWA) for CRLMs. The aim of this study was to evaluate the long-term survival and prognostic factors in patients with CRLMs undergoing PMWA.

METHODS

We retrospectively analyzed treatment and survival parameters of 210 patients with CRLMs who had received PMWA in a single center from January 2010 to December 2017. Prognostic factors for survival were evaluated by means of univariate and multivariate analyses.

RESULTS

The median follow-up time after PMWA was 48 months. The median overall survival (OS) time were 40.0 months (95% CI, 31.4 to 48.5 months), with 1-, 2, 3-, 4, and 5-year cumulative survival rates of 98.6%, 73.3%, 53.3%, 42.2%, and 32.9%, respectively. Tumor number (P = 0.004; HR: 1.838; CI: 1.213- 2.784), main tumor size (P = 0.017; HR: 1.631; CI: 1.093- 2.436), and serum CEA level (P = 0.032; HR: 1.559; CI: 1.039-2.340) were found as independent predictors of OS. The median OS time for patients with resectable lesions was 60.91 months (95% CI, 51.36 to 70.47 months), with 5-year cumulative survival rates of 53.5%.

CONCLUSION

PMWA is a safe and effective treatment for CRLMs, with a favorable long-term outcome. Multiple lesions, main tumor diameter>3 cm, and serum CEA >30 ng/ml have a significant negative effect on OS.

Surgical microwave ablation of otherwise non-resectable colorectal cancer liver metastases: Expanding opportunities for long term survival

BACKGROUND

Colorectal liver metastases (CRLM) are the most common extra-lymphatic metastases in colorectal cancers, however, only 15-20% of these patients are candidates for resection. We reviewed our institutional experience with 135 surgical ablations for unresectable CRLM.

METHODS

Retrospective review of surgically ablated CRLM from 2009 to 2018. Patient-specific variables were obtained from the medical record. Kaplan-Meier modeling was performed for survival analyses.

RESULTS

We ablated 135 CRLM in 36 patients over 40 procedures. Median age was 52 years and 58% of patients were male. All patients received systemic chemotherapy. The ablation procedure was completed laparoscopically in 68% of procedures. Median number of ablated lesions per patient was 2 (range 1-15). Median maximum diameter of ablated lesions was 1.9 cm (range 0.5-12.2). Median follow up of the study was 28 months. In this time, median disease-free survival was not reached. Of the 135 lesions ablated, the per-lesion recurrence rate was 6/135 (4.4%). Median overall survival was 81 months.

CONCLUSIONS

Surgical ablation of CRLM can provide excellent local control and long-term survival outcomes in patients who may otherwise not be candidates for other liver-directed therapies.

Efficacy and safety of percutaneous computed tomography-guided microwave ablation for colorectal cancer, oligometastatic liver-only disease: a single center's experience

Background

We retrospectively evaluated the effectiveness and safety of computed tomography-guided percutaneous microwave ablation (MWA) of metastatic liver disease in terms of 5-year overall survival and 5-year disease-free survival.

Methods

Institutional database research identified 32 colorectal cancer patients with oligometastatic liver-only disease who underwent percutaneous computed tomography-guided MWA. Contrast-enhanced computed tomography or magnetic resonance imaging was used for post-ablation follow up. Patient and tumor characteristics, MWA technique and complications were evaluated. In addition, the 5-year overall survival, the 5-year disease-free survival, and the potential factors affecting the survival of these patients were analyzed.

Results

Mean patient age was 72 years (male: female 21:11). In total 58 lesions were treated in 45 ablation sessions. Average lesion size was 2 cm (range 0.8-3.9 cm). The primary tumor for the majority of patients was in the colon (n=27), while in 5 patients it was located in the rectum. The majority of patients had 1 liver metastasis (n=16), 11 patients had 2, 4 patients had 3, and 1 patient had 4. Primary local tumor control was achieved in 91.3% (53/58) of the ablated lesions. Overall survival at 1, 3 and 5 years was 96.8%, 68.7% and 34.3%, respectively.

Conclusion

Computed tomography-guided percutaneous MWA for metastatic liver-only disease in oligometastatic patients is a feasible, safe and effective therapy with satisfactory long-term survival rates.

Factors predicting ablation site recurrence following percutaneous microwave ablation of colorectal hepatic metastases

BACKGROUND

Microwave ablation (MWA) is a recognised treatment option for liver metastases. The size of the tumour is a well-established factor that influences the success of MWA. However, the effect of "heat sink" on the success of MWA for hepatic metastases is unclear. The aim of this study was to determine whether heat sink effect is a factor that contributes to ablation site recurrence (ASR).

METHODS

A prospectively maintained database of patients who underwent percutaneous MWA for treatment of colorectal liver metastases was analysed. Imaging and demographic characteristics were compared between metastases that recurred following ablation and those that did not. Proximity to a large hepatic vein was defined as <10 mm.

RESULTS

126 ablations in 87 patients met the inclusion criteria and were studied over a median follow-up period of 28 (12-75) months. ASR was detected in 43 ablations (34%) and was associated with clinical risk score (CRS) ≥2 (OR 2.2 95% CI 1.3-3.3, p = 0.029), metastasis size (OR 0.953 95% CI (0.929-0.978), p < 0.001) and proximity to a large hepatic vein (OR 7.5 95%CI 2.4-22.8, p < 0.001). Proximity to a large hepatic vein was not associated with reduced overall survival (OS) but was associated with liver-specific recurrence (HR 4.7 95%CI 1.7-12.5, p = 0.004).

CONCLUSIONS

In addition to tumour size proximity to large hepatic venous structures is an independent predictor of ASR and liver-specific recurrence following MWA. However, this was not associated with overall survival.

The role of interventional oncology in the treatment of colorectal cancer liver metastases

Colorectal cancer is a leading cause of death both in Europe and worldwide. Unfortunately, 20-25% of patients with colorectal cancer already have metastases at the time of diagnosis, while 50-60% of the remainder will develop metastases later during the course of the disease. Although hepatic excision is the first-line treatment for patients with liver-limited colorectal metastases and is reported to prolong the survival of these patients, few patients are candidates. Locoregional therapy encompasses minimally invasive techniques practiced by interventional radiology. Most widely used locoregional therapies include ablative treatments (radiofrequency ablation, microwave ablation) and transcatheter intra-arterial therapies (transarterial chemoembolization, and radioembolization with yttrium-90).

The role of interventional oncology in the treatment of colorectal cancer liver metastases

Colorectal cancer is a leading cause of death both in Europe and worldwide. Unfortunately, 20-25% of patients with colorectal cancer already have metastases at the time of diagnosis, while 50-60% of the remainder will develop metastases later during the course of the disease. Although hepatic excision is the first-line treatment for patients with liver-limited colorectal metastases and is reported to prolong the survival of these patients, few patients are candidates. Locoregional therapy encompasses minimally invasive techniques practiced by interventional radiology. Most widely used locoregional therapies include ablative treatments (radiofrequency ablation, microwave ablation) and transcatheter intra-arterial therapies (transarterial chemoembolization, and radioembolization with yttrium-90).

Percutaneous Microwave Ablation Under CT Guidance for Hepatocellular Carcinoma: a Single Institutional Experience

BACKGROUND

Microwave ablation (MWA) is an emerging treatment for treatment of patients with hepatocellular carcinoma (HCC) not amenable of surgical resection.

PATIENTS AND METHODS

We searched for patients diagnosed as having small-, medium-, and large HCCs treated with MWA under CT guidance between 2010 and 2014. The main outcomes of interest were rates of complete ablation, complications, and overall survival. Rates of complete ablation were compared with Chi-square test, and estimated survival rates were calculated by means of Kaplan-Meier method.

RESULTS

Thirty-two patients with 45 HCC nodules received MWA. Seventeen (37.8%) nodules were <3 cm (small), 15 (33.3%) between 3 and 5 cm (medium), and 13 (28.9%) > 5 cm (large). Complete ablation was obtained in 94.1% of small tumors, 80% of medium tumors, and 53.8% of large tumors (p = 0.03). Two patients had HCC located in risk area (paracardiac position). Minor complications occurred after seven procedures (15.5%). Estimated median survival was 37 months (95% confidence interval 11.97-62.02). One-year OS was 82.7%, 2-year survival 68.9%, and 3-year survival 55.2%.

CONCLUSION

MWA is a versatile ablative method that can be applied in HCC at various stages, and also in lesions located in risk areas.

Colorectal liver metastases: surgery versus thermal ablation (COLLISION) - a phase III single-blind prospective randomized controlled trial

Background

Radiofrequency ablation (RFA) and microwave ablation (MWA) are widely accepted techniques to eliminate small unresectable colorectal liver metastases (CRLM). Although previous studies labelled thermal ablation inferior to surgical resection, the apparent selection bias when comparing patients with unresectable disease to surgical candidates, the superior safety profile, and the competitive overall survival results for the more recent reports mandate the setup of a randomized controlled trial. The objective of the COLLISION trial is to prove non-inferiority of thermal ablation compared to hepatic resection in patients with at least one resectable and ablatable CRLM and no extrahepatic disease.

Methods

In this two-arm, single-blind multi-center phase-III clinical trial, six hundred and eighteen patients with at least one CRLM (≤3 cm) will be included to undergo either surgical resection or thermal ablation of appointed target lesion(s) (≤3 cm). Primary endpoint is OS (overall survival, intention-to-treat analysis). Main secondary endpoints are overall disease-free survival (DFS), time to progression (TTP), time to local progression (TTLP), primary and assisted technique efficacy (PTE, ATE), procedural morbidity and mortality, length of hospital stay, assessment of pain and quality of life (QoL), cost-effectiveness ratio (ICER) and quality-adjusted life years (QALY).

Discussion

If thermal ablation proves to be non-inferior in treating lesions ≤3 cm, a switch in treatment-method may lead to a reduction of the post-procedural morbidity and mortality, length of hospital stay and incremental costs without compromising oncological outcome for patients with CRLM.

Trial registration

NCT03088150, January 11th 2017.

A radiologist's point of view in the presurgical and intraoperative setting of colorectal liver metastases

Multidisciplinary management of patients with metastatic colorectal cancer requires in each phase an adequate choice of the most appropriate imaging modality. The first challenging step is liver lesions detection and characterization, using several imaging modality ultrasound, computed tomography, magnetic resonance and positron emission tomography. The criteria to establish the metastases resectability have been modified. Not only the lesions number and site but also the functional volume remnant after surgery and the quality of the nontumoral liver must be taken into account. Radiologists should identify the liver functional volume remnant and during liver surgical procedures should collaborate with the surgeon to identify all lesions, including those that disappeared after the therapy, using intraoperative ultrasound with or without contrast medium.

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.

局部治疗手段在结直肠癌肝转移治疗中的价值

结直肠癌肝转移患者全身治疗是标准治疗, 应该作为每一种治疗策略的初始, 但局部治疗也发挥着重要价值. 手术完全切除肝转移灶仍是目前能治愈结直肠癌和胃肠道神经内分泌肿瘤肝转移的最佳方法. 射频消融主要应用于那些不可切除或术后复发的局限性病灶, 但受转移灶大小、数量和解剖位置的制约. 立体定向放射治疗作为一种非手术的局部治疗是安全、有效的. 微波消融、冷冻消融、高能聚焦超声刀、经皮穿刺瘤内注射无水乙醇、肝动脉栓塞或肝动脉化疗栓塞、肝动脉灌注化疗等也是重要的局部治疗手段, 在患者的综合治疗中发挥重要作用. 本文就以上内容作一综述.

Does primary tumor location impact the prognosis of colorectal liver metastases patients after microwave ablation? - Lessons from 10 years' experience

Thermal ablation has been considered as an alternative for local curative intent in patients with unresectable colorectal liver metastases. The influence of primary tumor location on the prognosis of colorectal liver metastases patients who have undergone microwave ablation has yet to be determined. We reviewed 295 patients who underwent microwave ablation for colorectal liver metastases at our institution between March 2006 and March 2016. Univariate and multivariate analyses were performed to identify predictors of overall and progression-free survival. Technical success was achieved in 96.6% of patients (n = 289), with a post-procedural complication rate of 2.0% (n = 6). After a median follow-up of 24 (range, 2–86) months, comparable overall survival rates (p = 0.583) were observed in patients with different primary tumor locations. Patients with colorectal liver metastases originating from left-sided primary colon cancer exhibited a better progression-free survival than patients whose colorectal liver metastases had originated from right-sided primary colon cancer (hazard ratio: 0.67, 95.0% confidence interval: 0.48–0.94; p = 0.012), which was further confirmed in a multivariate analysis after adjustment for other potential prognostic factors. Stratification based on primary tumor location should be taken into consideration in the assessment of disease progression in patients who intend to undergo microwave ablation for colorectal liver metastases.

The combination of systemic chemotherapy and local treatment may improve the survival of patients with unresectable metastatic colorectal cancer

With the development of systemic chemotherapy, the survival time of patients with advanced colorectal cancer (CRC) has increased. In addition, local treatments, such as microwave ablation and radioactive seed implantation, have been shown to be effective. However, the number of studies reporting on the effect of systemic chemotherapy combined with local treatments is limited. The present study was conducted to determine the effect of local treatment combined with systemic chemotherapy in patients with initial unresectable metastatic CRC (mCRC). Clinicopathological and follow-up data from 273 patients with initial unresectable mCRC between April, 2007 and October, 2013 were retrospectively analyzed. A total of 51 patients received minimally invasive treatments combined with systemic chemotherapy and 39 patients achieved tumor-free survival (TFS). The median TFS time was 9 months (range, 2–45 months); the median overall survival (OS) time was 40 months (range, 12–108 months). In patients who did not achieve TFS, the OS was 37 months. Thus, patients who achieved TFS exhibited a significantly longer OS compared with those who did not achieve TFS (P=0.049). The results of the univariate analysis demonstrated that certain characteristics, such as the number of lesions and maximum tumor diameter, were associated with the achievement of TFS. The patients assessed herein achieved TFS in response to local treatments combined with systemic chemotherapy. Furthermore, the achieved TFS provided an OS benefit.

New Perspectives in the Treatment of Colorectal Metastases

BACKGROUND

In recent years, the management of metastatic colorectal cancer has become more aggressive and more multidisciplinary. New treatment options have been proposed in addition to the standard approach of resection of liver metastases and chemotherapy.

SUMMARY

Selected patients with synchronous limited peritoneal and liver disease (peritoneal cancer index <12 and <3 liver metastases) can be scheduled for aggressive treatment, including cytoreductive surgery, hyperthermic intraperitoneal chemotherapy, and liver resection. This approach has achieved survival benefits, even if the treatment is unlikely to be curative in most patients. Moreover, liver transplantation has been recently reconsidered for liver-only metastases, resulting in the de facto reinstatement of the chance of surgery for some unresectable patients. Even though indications for liver transplantation remain to be standardized, preliminary studies have reported extremely promising outcomes. Radio-embolization has proven to be an effective additional tool for the treatment of unresectable tumors, and its potential role in association with chemotherapy for resectable disease is currently being investigated. Stereotactic body radiation therapy is a safe, non-invasive, and effective therapeutic option for patients with inoperable oligometastatic disease. Thanks to recent technical progress, high radiation doses can now be delivered in fewer fractions with excellent local disease control and a low risk of radiation-induced liver injury. Finally, radiofrequency ablation (RFA) for colorectal metastases has become more effective, with results approaching those of surgical series. New interstitial treatments, such as microwave ablation and irreversible electroporation, could overcome some of the limitations of RFA, thereby further expanding indications and optimizing outcomes.

KEY MESSAGES

Currently, a multidisciplinary approach to patients with colorectal liver metastases is mandatory. Aggressive surgical treatments should be integrated with all the available non-surgical options to maximize disease control and patient survival.

Hepatic Tumor Ablation

Tumor ablation is a safe and effective treatment available in the multidisciplinary care of the surgical oncology patient. The role of ablation is well established in the treatment of hepatocellular carcinoma and is becoming more accepted in the treatment of various malignancies metastatic to the liver, in particular colorectal cancer. Understanding the underlying technology, achieving appropriate applicator placement, using maximum energy delivery to create margins, and performing necessary adjunctive maneuvers are all required for successful tumor ablation.

Precoagulation-assisted parenchyma-sparing laparoscopic liver surgery: rationale and surgical technique

BACKGROUND

For the treatment of both primary and metastatic liver tumors, laparoscopic parenchyma-sparing surgery is advocated to reduce postoperative liver failure and facilitate reoperation in the case of recurrence. However, atypical and wedge resections are associated with a higher amount of intraoperative bleeding than are anatomical resections, and such bleeding is known to affect short- and long-term outcomes. Beyond the established role of radiofrequency and microwave ablation in the setting of inoperable liver tumors, the application of thermoablative energy along the plane of the liver surface to be transected results in a zone of coagulative necrosis, possibly minimizing bleeding of the cut liver surface during parenchymal transection.

METHODS

From January 2013 to March 2016, a total of 20 selected patients underwent laparoscopic ultrasound-guided liver resection with thermoablative precoagulation of the transection line.

RESULTS

During a period of 38 months, 50 laparoscopic thermoablative procedures were performed. Colorectal liver metastases were the most frequent diagnosis. Seventy-two percent of the nodules were removed using parenchymal transection with radiofrequency-precoagulation, while microwave-precoagulation was performed for 20 % of the resected nodules. The remaining 8 % of the nodules were treated by thermoablation alone. The hepatic pedicle was intermittently clamped in six patients. The mean blood loss was 290 mL, and four patients required perioperative transfusions.

CONCLUSIONS

Precoagulation-assisted parenchyma-sparing laparoscopic liver surgery can get minimal blood loss during parenchymal transection and lower the need for perioperative transfusions, providing a nonquantifiable margin of oncological safety on the remaining liver. Additional results from larger series are advocated to confirm these preliminary data.

The role of intraoperative ultrasonography in the diagnosis and management of focal hepatic lesions

Intraoperative ultrasonography (IOUS) has been widely utilized in hepatic surgery both as a diagnostic technique and in the course of treatment. Since IOUS involves direct-contact imaging of the target organ, it can provide high spatial resolution without interference from the surrounding structures. Therefore, IOUS may improve the detection, characterization, localization, and local staging of hepatic tumors. IOUS is also a real-time imaging modality capable of providing interactive information and valuable guidance in a range of procedures. Recently, contrast-enhanced IOUS, IOUS elastography, and IOUS-guided hepatic surgery have attracted increasing interest and are expected to lead to the broader implementation of IOUS. Herein, we review the various applications of IOUS in the diagnosis and management of focal hepatic lesions.