Radiofrequency ablation versus resection for technically resectable colorectal liver metastasis: a propensity score analysis

Benefits and drawbacks of radiofrequency ablation via percutaneous or minimally invasive surgery for treating hepatocellular carcinoma

The management of early stage hepatocellular carcinoma (HCC) presents significant challenges. While radiofrequency ablation (RFA) has shown safety and effectiveness in treating HCC, with lower mortality rates and shorter hospital stays, its high recurrence rate remains a significant impediment. Consequently, achieving improved survival solely through RFA is challenging, particularly in retrospective studies with inherent biases. Ultrasound is commonly used for guiding percutaneous RFA, but its low contrast can lead to missed tumors and the risk of HCC recurrence. To enhance the efficiency of ultrasound-guided percutaneous RFA, various techniques such as artificial ascites and contrast-enhanced ultrasound have been developed to facilitate complete tumor ablation. Minimally invasive surgery (MIS) offers advantages over open surgery and has gained traction in various surgical fields. Recent studies suggest that laparoscopic intraoperative RFA (IORFA) may be more effective than percutaneous RFA in terms of survival for HCC patients unsuitable for surgery, highlighting its significance. Therefore, combining MIS-IORFA with these enhanced percutaneous RFA techniques may hold greater significance for HCC treatment using the MIS-IORFA approach. This article reviews liver resection and RFA in HCC treatment, comparing their merits and proposing a trajectory involving their combination in future therapy.

Ablative techniques in colorectal liver metastases: A systematic review, descriptive summary of practice, and recommendations for optimal data reporting

BACKGROUND

Radiofrequency Ablation (RFA) and Microwave Ablation (MWA) are alternative treatments for colorectal liver metastasis (CRLM) patients that are unsuitable for resection. However, consensus is lacking regarding selection criteria, tumour characteristics, ablation technique delivery, and device settings. This study aims to summarise current evidence to inform future prospective studies.

METHODS

A systematic review was conducted following PRISMA guidelines. Studies assessing RFA and MWA treatment of CRLM were identified in Medline, Embase, Web of Science and the Cochrane database of systematic reviews, from inception until 31st August 2024.

RESULTS

Fifty-two studies were included (retrospective cohort n = 45, prospective cohort n = 5, non-randomized comparative studies n = 2). Fifty-four inclusion criteria were used across 45 studies and were not stated in 7 studies. Tumours varied in mean number [1-8] and diameter (1.54-4.35 cm). Neoadjuvant chemotherapy use (10-100 % of patients), ablation delivery approach (open n = 4, laparoscopic n = 11, percutaneous n = 26, mixed n = 5), anaesthetic mode (GA n = 18, LA n = 11, mixed n = 2) and delivering clinician (radiologist n = 11, surgeon n = 16, both n = 1) all varied. Thirty-two studies lacked complete ablation device settings. Six studies followed a standardized ablation algorithm and 14 studies had specific settings. Five-year survival ranged from 0 to 69.7 % for ablation.

CONCLUSIONS

There is significant heterogeneity in the reporting of study design, patient selection, and ablation techniques for CRLM. The lack of standardized approaches and inconsistent reporting of methodology and outcomes make it challenging to determine the optimal ablative treatment for CRLM. We recommend that future research should focus on clearly defining selection and treatment criteria, as well as treatment delivery.

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.

Management of Oligometastatic Colorectal Cancer

The management of oligometastatic colorectal cancer differs from the treatment of metastatic colorectal cancer, and it is essential that those who treat oligometastatic disease be familiar with the treatment options for these patients. Although definitive treatment is often surgical, there are situations where local therapies such as SBRT or ablative techniques may better serve the patient. Adjuvant therapy should be provided to all patients, and neoadjuvant chemotherapy should be considered as well. The role of immunotherapy is currently limited due to the lack of clinical trials in this area.

Liver resection versus ablation in geriatric populations - Does one method impart improved in-hospital mortality?

Objectives

This study aimed to compare surgical resection versus ablation for managing liver malignancies in patients 65 and older.

Material and Methods

Cases with liver tumors were extracted from the NSQIP database for patients aged ≥65 years. Following propensity score matching, multivariate Cox regression was used for 30-day morbidity and mortality for liver resection and ablation.

Results

Following a propensity score matching, 1048 patients were 1:1 matched for comorbid conditions. Patients stayed in the hospital three days longer after resection (p<0.001). Mortality was lower after ablation (p= 0.013). This difference was more prominent in patients with primary liver tumors (p= 0.008). Group A had a 10-fold lower risk of developing an abdominal abscess, a fourfold decrease in hospital-associated pneumonia (p= 0.001) and reintubation, a 10-fold reduction in bleeding requiring transfusion (p<0.001), and a three-fold decrease in risk of developing sepsis (p<0.001).

Conclusion

Despite being a generally sicker patient population with worse underlying liver function, ablative techniques were associated with a lower risk of adverse outcomes when compared to more aggressive resection of primary malignant tumors of the liver.

Value and prognostic factors of repeat hepatectomy for recurrent colorectal liver metastasis

BACKGROUND

More than 50% of patients with colorectal cancer develop liver metastases. Hepatectomy is the preferred treatment for resectable liver metastases. This review provides a perspective on the utility and relevant prognostic factors of repeat hepatectomy in recurrent colorectal liver metastasis (CRLM).

DATA SOURCES

The keywords "recurrent colorectal liver metastases", "recurrent hepatic metastases from colorectal cancer", "liver metastases of colorectal cancer", "repeat hepatectomy", "repeat hepatic resection", "second hepatic resection", and "prognostic factors" were used to retrieve articles published in the PubMed database up to August 2020. Additional articles were identified by a manual search of references from key articles.

RESULTS

Despite improvements in surgical methods and perioperative chemotherapy, recurrence remains common in 37%-68% of patients. Standards or guidelines for the treatment of recurrent liver metastases are lacking. Repeat hepatectomy appears to be the best option for patients with resectable metastases. The commonly reported prognostic factors after repeat hepatectomy were R0 resection, carcinoembryonic antigen level, the presence of extrahepatic disease, a short disease-free interval between initial and repeat hepatectomy, the number (> 1) and size (≥ 5 cm) of hepatic lesions, requiring blood transfusion, and no adjuvant chemotherapy after initial hepatectomy. The median overall survival after repeat hepatectomy ranged from 19.3 to 62 months, and the 5-year overall survival ranged from 21% to 73%. Chemotherapy can act as a test for the biological behavior of tumors with the goal of avoiding unnecessary surgery, and a multimodal approach involving aggressive chemotherapy and repeat hepatectomy might be the treatment of choice for patients with early recurrent CRLM.

CONCLUSIONS

Repeat hepatectomy is a relatively safe and effective treatment for resectable recurrent CRLM. The presence or absence of prognostic factors might facilitate patient selection to improve short- and long-term outcomes.

Survival Evidence of Local Control for Colorectal Cancer Liver Metastases by Hepatectomy and/or Radiofrequency Ablation

Hepatectomy and/or local ablation therapy have been recommended for colorectal cancer liver metastases (CRLM). However, they still lack strong evidence for their survival benefits, in addition to systemic therapy. This study aims to evaluate the survival evidence of hepatectomy and/or radiofrequency ablation (RFA) therapy in CRLM patients from a large multi-institutional database. A total of 20,251 patients with colorectal cancer, 4521 of whom were with CRLM, were screened for eligibility. Finally, 2612 patients (637 hepatectomy, 93 RFA, 92 combined hepatectomy and RFA, and 1790 non-aggressive treatment) were enrolled. Frequency matching analysis was used to adjust for baseline differences. The 5-year overall survival (OS) was as follows: hepatectomy alone was 47.8%, combined hepatectomy plus RFA was 35.9%, RFA alone was 29.2%, and the non-aggressive treatment group was 7.4%. Kaplan-Meier curves showed that hepatectomy, RFA, and combination were significantly associated with a better OS compared to those without aggressive local therapy (p < 0.001). Multivariate Cox regression analysis showed that male gender (hazard ratio (HR) 0.89; 95% confidence interval (CI), 0.81-0.97; p = 0.011), old age (≥60 years) (HR 1.20; 95% CI, 1.09-1.32; p < 0.001), high CEA level (>5 ng/mL) (HR 2.14; 95% CI, 1.89-2.42; p < 0.001), primary right-sided cancer (HR 1.35; 95% CI, 1.22-1.51; p < 0.001), extrahepatic metastasis (HR 1.46; 95% CI, 1.33-1.60; p < 0.001), systemic therapy (HR 0.7; 95% CI, 0.62-0.79; p < 0.001), and aggressive local therapy (hepatectomy vs. non-local therapy HR 0.22; 95% CI, 0.20-0.26; p < 0.001; RFA vs. non-local therapy HR 0.29; 95% CI, 0.29-0.41; p < 0.001) were independent factors associated with OS. In the frequency matching analysis, patients receiving hepatectomy and/or RFA resulted in a better OS than those without (p < 0.001). In conclusion, aggressive local treatment provides survival advantages over systemic therapy alone among CRLM patients.

Combined ablation and resection (CARe) for resectable colorectal cancer liver Metastases-A propensity score matching study

BACKGROUND

The efficacy of combining ablation and resection (CARe) in treating unresectable colorectal cancer liver metastases (CRLM) was well established. This study aimed to investigate the surgical and oncological outcomes of CARe strategy focusing on initially resectable CRLM.

PATIENTS AND METHODS

A total of 971 patients with resectable CRLM from a retrospective database of 1414 CRLM patients were enrolled, including 120 in the CARe group and 851 in the hepatectomy alone group. Short- and long-term outcomes were compared between groups using propensity score matching analysis.

RESULTS

After propensity score matching, 96 matched pairs of patients from each group were included. General characteristics of primary tumour and liver metastases were not statistically different between the CARe group and hepatectomy alone group. Disease-free survival (p = 0.257), intrahepatic recurrence-free survival (p = 0.329), and overall survival (p = 0.358) were similar between the two groups. Patients in CARe group had significantly reduced rate of major hepatectomy (5.2% vs. 21.9%, p = 0.001), lower incidence of postoperative hepatic insufficiency (0.0% vs. 5.2%, p = 0.023), and shortened postoperative hospital stay (7 d vs. 8 d, p = 0.019). Multivariate analysis showed that surgical approach did not affect oncologic outcome; liver metastasis with diameter >3 cm was an independent prognostic factor for hepatic recurrence-free and disease-free survival, and RAS status and lymph node metastasis at the primary site were independent prognostic factors for overall survival.

CONCLUSION

For patients with resectable CRLM, CARe may be a better treatment strategy than hepatectomy alone, as it could avoid major hepatectomy and get better surgical outcomes, while providing the similar oncologic results.

Combining Radiofrequency Ablation with Hepatic Resection for Liver-Only Colorectal Metastases: A Propensity-Score Based Analysis of Long-Term Outcomes

BACKGROUND

Combining liver resection (LR) with radiofrequency ablation (RFA) is nowadays an accepted option for treating colorectal liver metastases (CRLMs), but the number of lesions ablated is regularly described as a recurrence risk factor. In this study, we report our experience and determine the impact of RFA on long-term outcomes.

METHOD

This is a retrospective study including patients undergoing LR with or without RFA for CRLM. All variables influencing disease-free survival (DFS) and disease-specific survival (DSS) were examined through a Cox regression analysis before and after propensity-score matching (PSM).

RESULTS

Among the 128 patients included, 71 (55.5%) underwent LR alone and 57 (44.5%) underwent LR+RFA. With univariate analysis, LR+RFA showed a significantly worse DFS than LR alone (p = 0.028), which was not confirmed after PSM (p = 0.064). Thermal ablation did not influence DSS before or after matching (p = 0.282 and p = 0.189). When analyzing the subgroups of patients according to number of RFAs performed, no difference in long-term outcomes was observed (after PSM: p = 0.192 for DFS and p = 0.624 for DSS). Analysis of site of recurrence revealed that neither performing an RFA (p = 0.893) nor the number of lesions ablated (p = 0.093, p = 0.550, and p = 0.087 for 1, 2, and ≥ 2 RFAs) were associated with an increased risk of liver-only relapse.

DISCUSSION

In the setting of a parenchymal sparing strategy, combining RFA with LR is safe in terms of oncological outcomes. Tumor burden, rather than RFA performed, independently influences risk of recurrence and patient survival.

Economic evaluation of 18F-FDG PET/CT, MRI and CE-CT in selection of colorectal liver metastases eligible for ablation – A cost-effectiveness analysis

OBJECTIVES

Colorectal cancers (CRC) are among the world's most prevailing cancer entities. In a third of all cases, the patients have already developed distant metastases - mainly in the liver - at the time of detection. Colorectal liver metastases (CRLM) can be treated by surgical resection or, as is possible in most cases, by percutaneous ablation. For selecting the liver metastases eligible for radiofrequency ablation (RFA) or microwave ablation (MWA), the common imaging modalities are magnetic resonance imaging (MRI), positron emission tomography/computed tomography (PET/CT), and contrast-enhanced computed tomography (CE-CT). This study aims to evaluate those imaging modalities for selecting liver lesions eligible for ablation according to their long-term cost-effectiveness.

MATERIALS AND METHODS

A Markov model was applied, calculating quality-adjusted life years (QALYs) and accumulative costs for every diagnostic strategy, according to predefined input parameters obtained from published research. Further, sensitivity analyses were executed to prove the certainty of the calculations by running Monte-Carlo simulations with 30,000 reiterations. The Willingness-to-pay (WTP) is at $ 100,000. All calculations are based on the U.S. healthcare system.

RESULTS

CE-CT caused cumulative costs of $ 31,940.98 and 8,99 QALYs, whereas MRI caused $ 32,070.83 and 9,01 QALYs. PET/CT caused cumulative costs of $ 33,013.21 and 8,99 QALYs.

CONCLUSION

In conclusion, according to our analysis, MRI is the most cost-effective strategy for detecting liver metastases eligible for ablation and therefore should be seen as the gold standard.

Prediction of Local Tumor Progression After Microwave Ablation in Colorectal Carcinoma Liver Metastases Patients by MRI Radiomics and Clinical Characteristics-Based Combined Model: Preliminary Results

PURPOSE

To investigate the predictability of local tumor progression (LTP) after microwave ablation (MWA) in colorectal carcinoma liver metastases (CRLM) patients by magnetic resonance imaging (MRI) radiomics and clinical characteristics-based combined model.

MATERIALS AND METHODS

Forty-two consecutive CRLM patients (67 tumors) with post-MWA complete response at 1st month MRI were included in this retrospective study. One hundred and eleven radiomics features were extracted for each tumor and for each phase by manual segmentation from pre-treatment MRI T2 fat-suppressed (Phase 2) and early arterial phase T1 fat-suppressed sequences (Phase 1). A clinical model was constructed using clinical data, two combined models were created with feature reduction and machine learning by combining clinical data and Phase 2 and Phase 1 radiomics features. The predicting performance for LTP development was investigated.

RESULTS

LTP developed in 7 patients (16.6%) and 11 tumors (16.4%). In the clinical model, the presence of extrahepatic metastases before MWA was associated with a high probability of LTP (p < 0.001). The pre-treatment levels of carbohydrate antigen 19-9 and carcinoembryonic antigen were higher in the LTP group (p = 0.010, p = 0.020, respectively). Patients with LTP had statistically significantly higher radiomics scores in both phases (p < 0.001 for Phase 2 and p = 0.001 for Phase 1). The classification performance of the combined model 2, created by using clinical data and Phase 2-based radiomics features, achieved the highest discriminative performance in predicting LTP (p = 0,014; the area under curve (AUC) value 0.981 (95% CI 0.948-0.990). The combined model 1, created using clinical data and Phase 1-based radiomics features (AUC value 0,927 (95% CI 0.860-0.993, p < 0.001)) and the clinical model alone [AUC value of 0.887 (95% CI 0.807-0.967, p < 0.001)] had similar performance.

CONCLUSION

Combined models based on clinical data and radiomics features obtained from T2 fat-suppressed and early arterial-phase T1 fat-suppressed MRI are valuable markers in predicting LTP after MWA in CRLM patients. Large-scale studies with internal and external validations are needed to come to a firm conclusion on the predictability of radiomics models in CRLM patients.

Clinical Outcomes of Radiofrequency Ablation Combined with Transarterial Chemoembolization Using Degradable Starch Microsphere Mixed with Mitomycin C for the Treatment of Non-hepatocellular Carcinoma Malignant Liver Tumors

Purpose

To retrospectively evaluate the outcomes of radiofrequency ablation combined with transarterial chemoembolization using degradable starch microspheres for non-hepatocellular carcinoma malignant liver tumors.

Material and Methods

A total of 15 patients (13 men, 2 women; median age, 67 years) who underwent radiofrequency ablation immediately after transarterial chemoembolization using degradable starch microspheres for liver tumors between July 2011 and September 2020 were included in this study. Thirteen patients had liver metastases from colorectal cancer (n = 6), esophageal cancer (n = 2), lung cancer (n = 2), and other tumors (n = 3), and 2 patients had primary liver tumor of cholangiocellular carcinoma (n = 1) and gastrinoma (n = 1). Twenty tumors (median size, 16 mm) were treated in 17 sessions. Technical success, safety, local tumor progression, and overall survival were evaluated. Safety was assessed according to the clinical practice guideline of the Society of Interventional Radiology.

Results

All treatment procedures were successfully completed. There were no major complications. Grade-B complications of self-limiting pneumothorax (n = 1), vomiting (n = 1), and fever (n = 1) occurred in 1 session each. Local tumor progression developed in two tumors (local tumor progression rate, 10%, 2/20). The local tumor progression rates were 5% and 11% at 1 year and at 3 and 5 years, respectively. Tumor size of more than 20 mm (P = 0.0003) and contact with major vessels (P = 0.03) were significant risk factors for local tumor progression. The patients were treated with repeat radiofrequency ablation combined with transarterial chemoembolization using degradable starch microspheres. During median follow-up of 48 months (range, 4-77 months), 5 patients died (33%, 5/15). The overall survival rates were 100%, 85%, and 57% at 1, 3, and 5 years, respectively. The median overall survival time was 69 months.

Conclusions

Radiofrequency ablation combined with transarterial chemoembolization using degradable starch microspheres was safe and showed favorable local control for non-hepatocellular carcinoma malignant liver tumors.

Evaluation of the safety and efficacy of ultrasound-guided percutaneous radiofrequency ablation for hepatocellular carcinoma and liver metastases adjacent to the gallbladder

OBJECTIVE

To evaluate the safety and efficacy of ultrasound-guided percutaneous radiofrequency ablation (RFA) in patients with hepatocellular carcinoma (HCC) and liver metastases adjacent to the gallbladder (GB).

MATERIALS AND METHODS

A total of 113 patients with 118 liver lesions (63 HCC lesions and 55 liver metastases) adjacent to the gallbladder underwent RFA between March 2011 and June 2019. Gallbladder-related complications and technique effectiveness rates were evaluated based on the classification of liver tumors and the distance between the lesion and the gallbladder.

RESULTS

Gallbladder-related complications were observed in 13 patients. Among the patients with HCC, there was no significant difference between the ≤0.5 cm and >0.5 cm groups (p = .282). However, among the patients with liver metastases, the incidence of gallbladder-related complications in the ≤0.5 cm group was significantly higher than that in the >0.5 cm group (p = .025). The overall incidence of complications was significantly higher in the ≤0.5 cm group than in the >0.5 cm group (p = .020). Among the patients with lesions ≤3 cm, the technical effectiveness rate in the HCC group was significantly higher than in the liver metastasis group (p = .036).

CONCLUSION

RFA is a safe and effective treatment option for liver tumors adjacent to the gallbladder. Patients with lesions ≤0.5 cm from the gallbladder had higher gallbladder-related complications, especially patients with liver metastases. Among patients with lesions ≤3 cm, RFA showed greater technical effectiveness for treating HCC than for treating liver metastases.

Clinical strategy of conversion therapy and surgical treatment for liver metastases from colorectal cancer

Colorectal cancer is one of the common malignant tumors of the digestive system in clinical practice. Due to the anatomical characteristics of the colorectum itself, colorectal cancer is prone to liver metastasis. Approximately 15%-25% of colorectal cancer cases are complicated with liver metastasis at diagnosis, 15%-25% are complicated with liver metastasis after radical resection of colorectal cancer, and 80%-90% with liver metastasis cannot undergo radical resection initially. The 5-year survival rate is less than 5%, and liver metastasis is the main cause of death in patients with colorectal cancer. In recent years, with the clinical application of effective chemotherapy and molecular targeted drugs, as well as the rapid development of surgical techniques, an individualized safe, efficient, fast, treatment plan can be formulated according to patients' age, primary colorectal tumor location, degree of differentiation, Ras and B-Raf gene status, tumor size, number and distribution of metastases in the liver. By shrinking the tumor volume in the liver and increasing the residual liver volume, liver metastatic tumors can undergo surgical resection or disease-free status can be achieved in patients with liver metastasis. As a result, patients with colorectal liver metastases can achieve a 5-year survival rate of 30%-57%, which greatly improves the prognosis after operation. According to the postoperative adverse factors, individualized preventive measures are worked out to reduce the impact of adverse factors and improve the prognosis of patients with colorectal liver metastases. In this paper, we systematically discuss the clinical strategy of conversion therapy and surgical treatment for unresectable colorectal cancer liver metastases by reviewing the relevant domestic and foreign literature, so as to provide a theoretical reference for the selection of clinical treatment and program for patients with unresectable colorectal cancer liver metastases.

Local tumour control after radiofrequency or microwave ablation for colorectal liver metastases in relation to histopathological growth patterns

BACKGROUND

Regrowth after ablation is common, but predictive factors for local control are scarce. This study investigates whether histopathological growth patterns (HGP) can be used as a predictive biomarker for local control after ablation of colorectal liver metastases (CRLM).

METHODS

Patients who received simultaneous resection and ablation as first treatment for CRLM between 2000 and 2019 were considered eligible. HGPs were determined on resected CRLM according to international guidelines and were classified as desmoplastic or non-desmoplastic. As minimal inter-tumoural heterogeneity has been demonstrated, the HGP of resected and ablated CRLM were presumed to be identical. Local tumour progression (LTP) was assessed on postoperative surveillance imaging. Uni- and multivariable competing risk methods were used to compare LTP.

RESULTS

In total 221 patients with 443 ablated tumours were analysed. A desmoplastic HGP was found in 60 (27.1%) patients who had a total of 159 (34.7%) ablated lesions. Five-year LTP [95%CI] was significantly higher for ablated CRLM with a presumed non-desmoplastic HGP (37% [30-43] vs 24% [17-32], Gray's-test p = 0.014). On multivariable analysis, a non-desmoplastic HGP (adjusted HR [95%CI]; 1.55 [1.03-2.35]) was independently associated with higher LTP rates after ablation.

CONCLUSION

HGP is an independent predictor of local tumour progression following ablation of CRLM.

Gata6+ resident peritoneal macrophages promote the growth of liver metastasis

Emerging evidence suggests that resident macrophages within tissues are enablers of tumor growth. However, a second population of resident macrophages surrounds all visceral organs within the cavities and nothing is known about these GATA6⁺ large peritoneal macrophages (GLPMs) despite their ability to invade injured visceral organs by sensing danger signals. Here, we show that GLPMs invade growing metastases that breach the visceral mesothelium of the liver via the "find me signal", ATP. Depleting GLPMs either by pharmacological or genetic tools, reduces metastases growth. Apoptotic bodies from tumor cells induces programmed cell death ligand 1 (PD-L1) upregulation on GLPMs which block CD8⁺ T cell function. Direct targeting of GLPMs by intraperitoneal but not intravenous administration of anti-PD-L1 reduces tumor growth. Thermal ablation of liver metastases recruits huge numbers of GLPMs and enables rapid regrowth of tumors. GLPMs contribute to metastatic growth and tumor recurrence.

Single-centre survival analysis over 10 years after MR-guided radiofrequency ablation of liver metastases from different tumour entities

Background

Radiofrequency ablation (RFA) is a minimal-invasive, local therapy in patients with circumscribed metastatic disease. Although widely used, long time survival analysis of treated liver metastases is still pending while also analysing the patients’ experience of MR-based radiofrequency.

Methods

Monocentric, retrospective analysis of long-time overall and progression free survival (OS; PFS) of 109 patients, treated with MRI-guided hepatic RFA between 1997 and 2010, focusing on colorectal cancer patients (CRC). Complimentary therapies were evaluated and Kaplan Meier-curves were calculated. Patients’ experience of RFA was retrospectively assessed in 28 patients.

Results

1-, 3-, 5-, 10-year OS rates of 109 patients with different tumour entities were 83.4%, 53.4%, 31.0% and 22.9%, median 39.2 months, with decreasing survival rates for larger metastases size. For 72 CRC patients 1-, 3-, 5-, 10-year OS rates of 90.2%, 57.1%, 36.1% and 26.5% were documented (median 39.5 months). Thereof, beneficial outcome was detected for patients with prior surgery of the CRC including chemotherapy (median 53.0 months), and for liver metastases up to 19 mm (28.5% after 145 months). Hepatic PFS was significantly higher in patients with liver lesions up to 29 mm compared to larger ones (p = 0.035). 15/28 patients remembered RFA less incriminatory than other applied therapies.

Conclusions

This is the first single-centre, long-time OS and PFS analysis of MRI-guided hepatic RFA of liver metastases from different tumour entities, serving as basis for further comparison studies. Patients’ experience of MR based RFA should be analysed simultaneously to the performed RFA in the future.

Nomogram for predicting occurrence of synchronous liver metastasis in colorectal cancer: a single-center retrospective study based on pathological factors

Purpose

The purpose of this study was to explore the risk factors for synchronous liver metastasis (LM) of colorectal cancer (CRC) and to construct a nomogram for predicting the occurrence of synchronous LM based on baseline and pathological information.

Methods

The baseline and pathological information of 3190 CRC patients were enrolled in the study from the Department of Colorectal Surgery, the Second Affiliated Hospital of Harbin Medical University between 2012 and 2020. All patients were divided into development and validation cohorts with the 1:1 ratio. The characters of LM and none-LM patients in newly diagnosed colorectal cancer were utilized to explore the risk factors for synchronous LM with the univariate and multivariate logistic regression analyses. A predictive nomogram was constructed by using an R tool. In addition, receiver operating characteristic (ROC) curves was calculated to describe the discriminability of the nomogram. A calibration curve was plotted to compare the predicted and observed results of the nomogram. Decision-making curve analysis (DCA) was used to evaluate the clinical effect of nomogram.

Results

The nomogram consisted of six features including tumor site, vascular invasion (VI), T stage, N stage, preoperative CEA, and CA-199 level. ROC curves for the LM nomogram indicated good discrimination in the development (AUC = 0.885, 95% CI 0.854–0.916) and validation cohort (AUC = 0.857, 95% CI 0.821–0.893). The calibration curve showed that the prediction results of the nomogram were in good agreement with the actual observation results. Moreover, the DCA curves determined the clinical application value of predictive nomogram.

Conclusions

The pathologic-based nomogram could help clinicians to predict the occurrence of synchronous LM in postoperative CRC patients and provide a reference to perform appropriate metastatic screening plans and rational therapeutic options for the special population.

Preventing Futile Liver Resection: A Risk-Based Approach to Surgical Selection in Major Hepatectomy for Colorectal Cancer

BACKGROUND

Early recurrence following liver resection for metastatic colorectal cancer generally portends poor survival. We sought to identify factors associated with early disease recurrence after major hepatectomy for metastatic colorectal cancer in order to improve patient selection and prevent futile hepatectomy.

METHODS

Sequential major (four or more segments) liver resections performed for metastatic colorectal cancer between 1995 and 2019 were selected from our prospectively maintained database. Univariate analyses, multivariable regression modelling, and survival analyses were used to identify predictors of futile resection (recurrence within 6 months of hepatectomy).

RESULTS

Of 259 patients included, the median age was 61.3 years (interquartile range [IQR] 15.3) and the median number of liver tumors was 3.0 (IQR 2.0); 78.0% of patients received prehepatectomy chemotherapy. Surgeries were right (56.4%), left (19.3%), and extended hepatectomy (24.3%). Futile resection occurred in 26 (12.6%) patients. Margin positivity was similar in the futile resection group compared with the non-futile resection group (11.5% vs. 11.4%). Extrahepatic disease that disappeared with chemotherapy was present in 23.1% of patients with a futile resection and 7.2% of those without (p = 0.019). After multivariable regression, the factors predictive of futile resection were extrahepatic disease (odds ratio [OR] 5.6; p = 0.004), more than three liver lesions (OR 4.9; p = 0.001), and extended hepatectomy (OR 2.6; p = 0.038). Notably, 70.8% of futile recurrences occurred within the liver remnant and 20.8% were pulmonary metastases. Overall survival was 11.7 months (95% confidence interval [CI] 7.1-16.2) for the futile resection cohort versus 45.6 (95% CI 39.1-52.1) for non-futile hepatectomies (p < 0.001).

CONCLUSIONS

Futile hepatic resection can be predicted based on preoperative factors and carries a poor prognosis. Improved risk stratification for futility will aid in patient selection and treatment discussions.

Multielectrode Radiofrequency Ablation for Resectable Metachronous Liver Metastasis from Colorectal Cancer

The outcome of radiofrequency ablation (RFA) for liver metastases from colorectal cancer (CRLM) has been thought to be inferior to metastasectomy. However, the recent development of multielectrode RFA (multi-RFA) systems has made the ablation zone larger and more complete. Thus, we assessed the survival benefits of this modality in cases of metachronous CRLM. This retrospective study assessed patients diagnosed with resectable metachronous CRLM between 2013 and 2016; 132 patients were categorized by treatment for liver metastases: multi-RFA (n = 68), hepatectomy (n = 34), or systemic treatment only (n = 30). Therapeutic effectiveness, outcomes, and intervention-related complications were compared between groups. Median overall survival (OS), recurrence-free survival (RFS), and intrahepatic recurrence-free survival (IHRFS) were 69.8, 85.2, and 59.7 months for the hepatectomy group; 53.4, 41.3, and 32.3 months for the multi-RFA group; and 19.1, 7.1, and 7.1 months for the systemic treatment group. No significant differences were observed between the multi-RFA and hepatectomy groups after a median follow-up of 59.8 months. This study demonstrated that multi-RFA and hepatectomy provide similar survival benefits for patients with resectable CRLM. Multi-RFA may represent a reliable treatment option for the management of resectable liver metastases.

Recurrence and survival following microwave, radiofrequency ablation, and hepatic resection of colorectal liver metastases: A systematic review and network meta-analysis

BACKGROUND

Gold standard for colorectal liver metastases (CRLM) remains hepatic resection (HR). However, patients with severe comorbidities, unresectable or deep-situated resectable CRLM are candidates for ablation. The aim of the study was to compare recurrence rate and survival benefit of the microwave ablation (MWA), radiofrequency ablation (RFA) and HR by conducting the first network meta-analysis.

DATA SOURCES

Systematic search of the literature was conducted in the electronic databases. Both updated traditional and network meta-analyses were conducted and the results were compared between them.

RESULTS

HR cohort demonstrated significantly less local recurrence rate and better 3- and 5-year disease-free (DFS) and overall survival (OS) compared to MWA and RFA cohorts. HR cohort included significantly younger patients and with significantly lower preoperative carcinoembryonic antigen (CEA) by 10.28 ng/mL compared to RFA cohort. Subgroup analysis of local recurrence and OS of solitary and ≤ 3 cm CRLMs did not demonstrate any discrepancies when compared with the whole sample.

CONCLUSIONS

For resectable CRLM the treatment of choice still remains HR. MWA and RFA can be used as a single or adjunct treatment in patients with unresectable CRLM and/or prohibitive comorbidities.

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.

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.

Ten-Year Outcomes of Percutaneous Radiofrequency Ablation for Colorectal Cancer Liver Metastases in Perivascular vs. Non-Perivascular Locations: A Propensity-Score Matched Study

Purpose

To compare long-term outcomes of percutaneous radiofrequency ablation for colorectal liver metastases in perivascular versus non-perivascular locations.

Methods

This retrospective study included 388 consecutive patients with colorectal liver metastases (246 men, 142 women; age range 27–86 years) who underwent percutaneous radiofrequency ablation between January 2006 and December 2018. Propensity-score matching was performed for groups with perivascular and non-perivascular colorectal liver metastases. Rates of accumulative local tumor progression, overall survival, intra/extrahepatic recurrence, and complications were compared between the two groups.

Results

We successfully matched 104 patients each in the perivascular and non-perivascular groups (mean age: 60.1 ± 11.5 and 60.1 ± 11.3 years, respectively). Cumulative local tumor progression rates at 6 months, 1 years, 3 years, and 5 years, respectively, were 8.8%,14.8%, 18.9%, and 18.9% in the perivascular group and 8.8%, 13.1%, 15.5%, and 15.5% in the non-perivascular group. The 1-, 3-, 5-, and 10-year overall survival rates, respectively, were 91.3%, 45.6%, 23.9%, and 18.7% in the perivascular group and 88.0%, 47.2%, 27.2%, and 22.6% in the non-perivascular group. No significant between-group differences were detected in cumulative local tumor progression (p=0.567, hazard ratio: 1.224) or overall survival (p = 0.801, hazard ratio: 1.047). The major complication rate was 1.0% (1/104, p > 0.999) in both groups. Tumor size was the only independent prognostic factor for local tumor progression (hazard ratio: 2.314; p = 0.002). On multivariate analysis for overall colorectal liver metastases, tumor diameter >3 cm, tumor location in the right colon, multiple tumors, and extrahepatic metastases before radiofrequency ablation (hazard ratios: 2.046, 1.920, 1.706, and 1.892, respectively; all p < 0.001) and intrahepatic recurrence (hazard ratio: 1.564; p = 0.002) were associated with poor overall survival.

Conclusion

Cumulative local tumor progression, overall survival, and major complications rates did not differ significantly between perivascular and non-perivascular colorectal liver metastases after percutaneous radiofrequency ablation. For perivascular colorectal liver metastases, percutaneous radiofrequency ablation is a safe and effective treatment option.

Comparative analysis of radiofrequency ablation and resection for colorectal liver metastases in caudate lobe: a retrospective study

Objective: To assess the therapeutic efficiency of radiofrequency ablation (RFA) for colorectal liver metastases (CRLM) in the caudate lobe compared with that of surgical resection.Methods: After approved by institutional review board, we retrospectively reviewed 20 patients with caudate CRLM treated by RFA or resection between 2006 and 2017. Comparative analysis was performed based on the different therapies, including patient characteristics, therapeutic outcomes, recurrences, and survivals.Results: During the median follow-up of 7 years (range, 2 -11 years), no differences in complications and recurrences were found between RFA and surgery groups (p > .05). The median overall survival (OS) of patients after RFA and resection were 41 months (95% confidence interval (CI) 23.5-70.5) and 54 months (95% CI 31.1-77.7), respectively (p = .627, hazard radio (HR) 0.7, 95% CI 0.2-2.6). However, OS of resection group was better than that of RFA group for large caudate CRLMs (>3 cm) (p = .042, HR 4.4, 95% CI 0.6-32.6).Conclusions: RFA is a feasible, safe, and effective treatment for CRLM in the caudate. Surgical resection revealed superior outcomes in the treatment of caudate CRLMs, particularly in cases with a hepatic tumor size  >3 cm.

Follow-Up 18F-FDG PET/CT versus Contrast-Enhanced CT after Ablation of Liver Metastases of Colorectal Carcinoma-A Cost-Effectiveness Analysis

PURPOSE

After a percutaneous ablation of colorectal liver metastases (CRLM), follow-up investigations to evaluate potential tumor recurrence are necessary. The aim of this study was to analyze whether a combined 18F-Fluordesoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT) scan is cost-effective compared to a contrast-enhanced computed tomography (CE-CT) scan for detecting local tumor progression.

MATERIALS AND METHODS

A decision model based on Markov simulations that estimated lifetime costs and quality-adjusted life years (QALYs) was developed. Model input parameters were obtained from the recent literature. Deterministic sensitivity analysis of diagnostic parameters based on a Monte-Carlo simulation with 30,000 iterations was performed. The willingness-to-pay (WTP) was set to $100,000/QALY.

RESULTS

In the base-case scenario, CE-CT resulted in total costs of $28,625.08 and an efficacy of 0.755 QALYs, whereas 18F-FDG PET/CT resulted in total costs of $29,239.97 with an efficacy of 0.767. Therefore, the corresponding incremental cost-effectiveness ratio (ICER) of 18F-FDG PET/CT was $50,338.96 per QALY indicating cost-effectiveness based on the WTP threshold set above. The results were stable in deterministic and probabilistic sensitivity analyses.

CONCLUSION

Based on our model, 18F-FDG PET/CT can be considered as a cost-effective imaging alternative for follow-up investigations after percutaneous ablation of colorectal liver metastases.

Circulating Tumor DNA in KRAS positive colorectal cancer patients as a prognostic factor - a systematic review and meta-analysis

BACKGROUND

Liquid biopsy is a novel tool in oncology. It provides minimally invasive detection of tumor specific DNA. This review summarizes data on presence of circulating tumor DNA in serum or plasma of CRC patients as a potential negative prognostic factor.

MATERIALS AND METHODS

The systematic review was performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The search was performed using PubMed, Web of Science and Scopus.

RESULTS

In total 18 articles with a total of 1779 patients met the inclusion criteria. Six out of 8 studies found that presence of ctDNA in plasma/serum was associated with inferior overall survival. All 6 studies found that high concentrations of ctDNA in plasma/serum was associated with inferior overall survival.

CONCLUSIONS

Presence or high concentrations of KRAS mutation in plasma or serum were associated with inferior prognosis. Establishing cut-off concentrations is warranted for further clinical implementation of liquid biopsy.

Role of yttrium-90 selective internal radiation therapy in the treatment of liver-dominant metastatic colorectal cancer: an evidence-based expert consensus algorithm

Surgical resection of colorectal liver metastases is associated with greater survival compared with non-surgical treatment, and a meaningful possibility of cure. However, the majority of patients are not eligible for resection and may require other non-surgical interventions, such as liver-directed therapies, to be converted to surgical eligibility. Given the number of available therapies, a general framework is needed that outlines the specific roles of chemotherapy, surgery, and locoregional treatments [including selective internal radiation therapy (SIRT) with Y-90 microspheres]. Using a data-driven, modified Delphi process, an expert panel of surgical oncologists, transplant surgeons, and hepatopancreatobiliary (HPB) surgeons convened to create a comprehensive, evidence-based treatment algorithm that includes appropriate treatment options for patients stratified by their eligibility for surgical treatment. The group coined a novel, more inclusive phrase for targeted locoregional tumor treatment (a blanket term for resection, ablation, and other emerging locoregional treatments): local parenchymal tumor destruction therapy. The expert panel proposed new nomenclature for 3 distinct disease categories of liver-dominant metastatic colorectal cancer that is consistent with other tumor types: (I) surgically treatable (resectable); (II) surgically untreatable (borderline resectable); (III) advanced surgically untreatable (unresectable) disease. Patients may present at any point in the algorithm and move between categories depending on their response to therapy. The broad intent of therapy is to transition patients toward individualized treatments where possible, given the survival advantage that resection offers in the context of a comprehensive treatment plan. This article reviews what is known about the role of SIRT with Y-90 as neoadjuvant, definitive, or palliative therapy in these different clinical situations and provides insight into when treatment with SIRT with Y-90 may be appropriate and useful, organized into distinct treatment algorithm steps.

Resection vs. ablation for lesions characterized as resectable-ablative within the colorectal liver oligometastases criteria: a propensity score matching from retrospective study

Background

There has been no prospective or retrospective studies reporting the comparison outcome between surgery and ablation for resectable-ablative (lesions could be treated by resection or complete ablation) colorectal liver oligometastases (CLOM). The purpose of this study was to compare the efficacy and prognostic difference in patients who underwent R0 resection vs. complete ablation within the resectable-ablative CLOM criteria.

Methods

From January 2008 to May 2018, a total of 2,367 patients diagnosed with colorectal liver metastases were included in this observational study. The metastasis was characterized by only limited to liver with number ≤5, size ≤5 cm, and resectable-ablative (lesions could be treated by resection or complete ablation). The evaluated indications, including liver progression-free survival (LPFS), overall survival (OS), survival rates, pattern and number of recurrences, and complications, were compared by using propensity score matching (PSM). The Kaplan-Meier curves were generated, and a log-rank test was performed. The Cox regression model was used for univariate and multivariate analyses to identify predictors of outcomes.

Results

A total of 421 consecutive patients were eligible for this study, with 250 and 171 undergoing R0 resection and complete ablation, respectively. PSM identified 145 patients from each group. The 1-, 3-, 5- and 8-year OS rates in the resection group and the ablation group were 95.8% vs. 95.0%, 69.8% vs. 60.1%, 53.6% vs. 42.5%, and 45.1% vs. 32.9% (p = 0.075), respectively. The median LPFS in the resection group was significantly longer than that in the ablation group (35 months vs. 15 months, p = 0.011). No statistical difference was found in LPFS between the two groups when comparing ≤3 cm liver metastases. For liver metastasis >3 cm, the median LPFS in the resection group and ablation group was 11 months and 5 months, respectively (p = 0.001). In terms of high risk of clinical risk score (CRS), the resection group showed longer LPFS than the ablation group (median 18 months vs. 10 months, p = 0.043).

Conclusion

For patients within the CLOM criteria suggesting that liver metastases were resectable as well as ablative, resection could result in longer liver recurrence-free survival than ablation in cases with size >3 cm or high risk of CRS. But for ≤3 cm liver metastases, their treatment efficacies were comparable.

Possible involvement of HSP70 in pancreatic cancer cell proliferation after heat exposure and impact on RFA postoperative patient prognosis

Purpose

As an alleviative treatment measured in patients with unresectable advanced pancreatic cancer, radiofrequency ablation (RFA) needed more clinical data to prove its advantages and to explore limitations in its utilization. This study was determined to observe the efficacy of RFA, and to explore its impact on perioperative periphery carcinoma as well as the normal pancreatic tissues.

Methods

Clinical data of 32 patients with pancreatic cancer accepted RFA surgery were collected. Followed up patients' pain degree and the changes in serum tumor markers CA19-9 and CA 242 before and after surgery. Ex vivo, gave human pancreatic cancer cell line PANC-1 heat treatment to simulate the heat exposure condition periphery carcinoma was experienced during RFA surgery, and to observe the proliferation rate and HSP70 expression change compared with control group.

Results

Of the 32 patients, 1 died of upper gastrointestinal hemorrhage, and 29 survived for more than 5 months, 2 of which for more than 16 months. The average CA19-9 and CA 242 levels of the patients were significantly decreased in 3 months after surgery (t = 9.873, 5.978, P < 0.001). During in vitro experiments, the proliferation rate of PANC-1 cells after heating was significantly increased, accompanied with the increased HSP70 expression. The addition of HSP70 inhibitor can inhibit the rise of proliferation after heat therapy.

Conclusion

Utilizing RFA treat patients with unresectable advanced pancreatic cancer, could effectively relieve the pain, decline jaundice, and deduce tumor marker levels significantly. However, it failed to extend the long-term survival rate of the patients significantly. This study found that a higher proliferative rate accompanied with a higher HSP70 expression level were observed on in vitro cultured pancreatic carcinoma cells after heat treatment, which could be altered by HSP70 inhibitor. And these findings indicated that the heat exposure might impact periphery carcinoma during RFA surgery and HSP70 might play an important role in patients' prognosis.

Management of Liver Oligometastatic Esophageal Cancer: Overview and Critical Analysis of the Different Loco-Regional Treatments

Esophageal cancer (EC) is an aggressive disease that is associated with a poor prognosis. Since metastastic EC is usually considered suitable only for palliative therapy with an estimated 5-year overall survival (OS) less than 5%, the optimal management of patients with liver oligometastatic EC (LOEC) is still undefined. The aim of this review is to provide an overview of the different treatment options for LOEC. A literature search was conducted using PubMed, Embase, and Cochrane to identify articles evaluating different treatment strategies for LOEC. Among 828 records that were identified, 20 articles met the inclusion criteria. These studies included patients who have undergone any type of surgical procedure and/or loco-regional therapy. Liver resection resulted in the best survival for patients with low tumor burden (3 lesions): 5-year OS 30–50% versus 8–12% after only chemotherapy (CHT). The 5-year OS of loco-regional therapies was 23% with a local recurrence risk ranging 0–8% for small lesions (2 to 3 cm). An aggressive multidisciplinary approach for LOEC patients may improve survival. Surgery seems to be the treatment of choice for resectable LOEC. If unfeasible, loco-regional therapies may be considered. In order to better select these patients and offer a chance of cure, prospective trials and a definition of treatment protocols are needed.

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.

Ablation or Resection for Colorectal Liver Metastases? A Systematic Review of the Literature

Background: Successful use of ablation for small hepatocellular carcinomas (HCC) has led to interest in the role of ablation for colorectal liver metastases (CRLM). However, there remains a lack of clarity about the use of ablation for colorectal liver metastases (CRLM), specifically its efficacy compared with hepatic resection. Methods: A systematic review of the literature on ablation or resection of colorectal liver metastases was performed using MEDLINE, Cochrane Library, and Embase until December 2018. The aim of this study was to summarize the evidence for ablation vs. resection in the treatment of CRLM. Results: This review identified 1,773 studies of which 18 were eligible for inclusion. In the majority of the studies, overall survival (OS) and disease-free survival (DFS) were significantly higher and local recurrence (LR) rates were significantly lower in the resection groups. On subgroup analysis of solitary CRLM, resection was associated with improved OS, DFS, and reduced LR. Three series assessed the outcome of resection vs. ablation for technically resectable CRLM, and showed improved outcome in the resection group. In fact, there were no studies showing a survival advantage of ablation compared to resection in the treatment of CRLM. Conclusions: Resection remains the "gold standard" in the treatment of CRLM and should not be replaced by ablation at present. This review supports the use of ablation only as an adjunct to resection and as a single treatment option when resection is not safely possible.

Aggressive Graphic/Surgical R0 Resection and Jejunal Interposition with Preservation of Mesojejunal Autonomic Nerves in Patients with Stage IV Esophagogastric Junction Adenocarcinoma: A Report of 3 Cases

BACKGROUND Three patients with stage IV esophagogastric junction cancer (EGJC) underwent extended resection to achieve a graphic/surgical R0 status (no visible remnant of viable tumor in imaging/surgical findings) and adjuvant chemotherapy from the early postoperative period. We also introduced use of our digestive reconstruction technique in these patients. CASE REPORT We used jejunal interposition for digestive reconstruction, which involved end-to-end jejunojejunostomy with a biofragmentable anastomosis ring. The mesojejunal autonomic nerves of the lifted jejunum were preserved. The first adenocarcinoma involved the perilesional lymph nodes (LNs). Graphic/surgical R0 resection was completed by para-aortic LN dissection. The diagnosis (Japanese Classification of Gastric Carcinoma) was stage IV [pM1(LYM)]. Adjuvant chemotherapy began on postoperative day (POD) 11. The second adenocarcinoma was accompanied by a solitary lung metastasis. Intraoperative cytology of ascitic fluid was positive, and cisplatin was intraperitoneally administered. Adjuvant chemotherapy began on POD 10. The solitary lung metastasis was then resected, and graphic/surgical R0 resection was achieved. The diagnosis was stage IV [pM1(PUL) and CY1]. The third adenocarcinoma was accompanied by multiple liver metastases and metastatic regional LNs. The diagnosis was stage IV [H1]. Systemic chemotherapy was repeated. Only a solitary liver metastasis remained and was treated by radiofrequency ablation. Conversion surgery was conducted, achieving graphic/surgical R0 resection. Systemic chemotherapy was continued from POD 10. CONCLUSIONS For patients with stage IV EGJC, extended resection to achieve a graphic/surgical R0 status is still controversial, and systemic chemotherapy is important. The results of the present study suggest that our physiological reconstruction technique does not affect the efficacy of other therapies, such as adjuvant chemotherapy.