Two-Stage Hepatectomy Versus 1-Stage Resection Combined With Radiofrequency for Bilobar Colorectal Metastases: A Case-Matched Analysis of Surgical and Oncological Outcomes

Preoperative imaging of colorectal liver metastases: what the radiologist and the multidisciplinary team need to know

The management of patients with colorectal liver metastases (CRLM) has transformed over the past 2 decades. Advances in surgical techniques, systemic therapies, and local treatments have resulted in a paradigm shift. Disease that would once have been considered terminal is now frequently treated aggressively with both a disease-free and overall survival benefit. In line with the expanding range of treatment options, there has been an increase in the volume and complexity of imaging required in the management of these patients to ensure optimal patient selection and outcome. The radiologist plays a pivotal role in interpreting these studies, conveying the relevant information and informing the discussion at multidisciplinary team meetings. The purpose of this review is to provide an update for radiologists on the current surgical management of patients with CRLM highlighting specific imaging information that is required by the multidisciplinary team when assessing resectability and/or the need for additional liver-directed therapies.

Resection versus resection with ablation: Analysis from the colorectal liver operative metastasis international collaborative

BACKGROUND

Thermal ablation has recently become a key therapy for the treatment of colorectal liver metastasis (CLM). However, the role of ablation in combination with resection has not yet been firmly established. We hypothesize that in patients with CLM, those who undergo liver resection with ablation (RA) have similar outcomes compared with those who undergo liver resection only.

METHODS

We reviewed a multicenter international database of 906 surgical procedures for CLM from 5 high volume hepatobiliary surgical units. Patients undergoing RA (n = 63) were matched based on the number of lesions and tumor size using a 1:1 balanced propensity score analysis with those having resection only (n = 63). Our primary outcomes were overall survival (OS) and disease-free survival (DFS).

RESULTS

The mean age of our cohort was 58 ± 11 years, with 43% females. With a median follow-up of 70.8 months, patients in the resection and RA group had a median OS of 45.1 and 54.8 months (p = 0.71), respectively. The median DFS was 22.7 and 14.2 months (p = 0.045), respectively. Using a multivariate Cox proportional hazards regression model, the treatment approach was not associated with OS (p = 0.94) or DFS (p = 0.059). A higher number of lesions is independently associated with worse DFS (hazard ratio: 1.12, p < 0.01). When there was disease recurrence, the region of recurrence was similar between the RA versus resection only groups (p = 0.27), but there was a shorter time to recurrence in the RA group (p = 0.002).

CONCLUSION

For CLM, the treatment approach was not significantly associated with OS or DFS, while tumor biology likely played an important role. Prospective research on the quality and effectiveness of thermal ablation combined with hepatic resection is warranted.

Adjuvant chemotherapy is associated with better oncological outcomes after ALPPS for colorectal liver metastases

ALPPS enables complete tumor resection in a shorter interval and a larger number of patients than classic two-stage hepatectomies. However, there is little evidence regarding long-term outcomes in patients with colorectal liver metastases (CLM). This study aims to evaluate the short and long-term outcomes of ALPPS in patients with CRM. Single-cohort, prospective, observational study. Patients with unresectable CLM due to insufficient liver remnant who underwent ALPPS between June 2011 and June 2021 were included. Of 32 patients treated, 21 were male (66%) and the median age was 56 years (range = 29-81). Both stages were completed in 30 patients (93.7%), with an R0 rate of 75% (24/32). Major morbidity was 37.5% and the mortality nil. Median overall survival (OS) and recurrence-free survival (RFS) were 28.1 and 8.8 months, respectively. The 1-3, and 5-year OS was 86%, 45%, and 21%, and RFS was 42%, 14%, and 14%, respectively. The only independent risk factor associated with poor RFS (5.7 vs 11.6 months; p = 0.038) and OS (15 vs 37 months; p = 0.009) was not receiving adjuvant chemotherapy. KRAS mutation was associated with worse OS from disease diagnosis (24.3 vs. 38.9 months; p = 0.025). ALPPS is associated with favorable oncological outcomes, comparable to traditional strategies to increase resectability in patients with CLM and high tumor burden. Our results suggest for the first time that adjuvant chemotherapy is independently associated with better short- and long-term outcomes after ALPPS. Selection of patients with KRAS mutations should be performed with caution, as this could affect oncological outcomes.

Achievement of textbook outcome after hepatectomy combined with thermal ablation for colorectal liver metastases

BACKGROUND

Hepatic resection combined with intraoperative ablation has been described as a technical solution potentially widening the resectability rate of patients with colorectal liver metastases (CRLM). Nevertheless, the perioperative and oncological benefit provided by this combined approach remains unclear. We hypothesized that textbook outcome (TO), which is a composite measure achieved for patients for whom some desired health indicators are met, may help to refine the indications of this approach.

METHODS

Patients submitted to hepatectomy with curative intent in combination with radiofrequency ablation or microwave ablation for CRLM ≤ 3 cm in two tertiary referral centers were included. TO was defined according to a recent definition for liver surgery based on a Delphi process including also the achievement of complete radiological response of the ablated lesion/s at 4 weeks.

RESULTS

Between 2015 and 2022, 112 patients were enrolled. Among them, 63 (56.2%) achieved a TO. According to multivariate analysis, minimally invasive (MI) approach (OR 2.72, 95% CI 0.99-7.48, p = 0.050), simultaneous CR resection (OR 0.28, 95% CI 0.11-0.70, p = 0.007), tumor burden score (OR 0.89, 95% CI 0.82-0.96, p = 0.004), and major hepatectomy (OR 0.12, 95% CI 0.03-0.52, p = 0.004) were significantly associated with the achievement of TO. Median overall survival was longer in those patients who were able to achieve a TO compared to those who did not.

CONCLUSIONS

The combination of hepatectomy and ablation constitutes a valuable solution in patients affected by multiple CRLM and it may provide, also using a MI approach, adequate perioperative and oncological outcomes, allowing to achieve TO, however, in a selected number of patients and depending on several factors including the burden of disease.

Pan-European survey on current treatment strategies in patients with upfront resectable colorectal liver metastases

BACKGROUND

There is a lack of consensus on the definition of upfront resectability and use of perioperative systemic therapy for colorectal liver metastases (CRLM). This survey aimed to summarize the current treatment strategies for upfront resectable CRLM throughout Europe.

METHODS

A survey was sent to all members of the European-African Hepato-Pancreato-Biliary Association to gain insight into the current views on resectability and the use of systemic therapy for upfront resectable CRLM.

RESULTS

The survey was completed by 87 surgeons from 24 countries. The resectability of CRLM is mostly based on the volume of the future liver remnant, while considering tumor biology. Thermal ablation was considered as an acceptable adjunct to resection in parenchymal-sparing CRLM surgery by 77 % of the respondents. A total of 40.2 % of the respondents preferred standard perioperative systemic therapy and 24.1 % preferred standard upfront local treatment.

CONCLUSION

Among the participating European hepato-pancreato-biliary surgeons, there is a high degree of consensus on the definition of CRLM resectability. However, there is much variety in the use of adjunctive thermal ablation. Major variations persist in the use of perioperative systemic therapy in cases of upfront resectable CRLM, stressing the need for further evidence and a consensus.

Debulking Hepatectomy for Colorectal Liver Metastasis Conveys Survival Benefit

(1) Background: Despite advances in surgical technique and systemic chemotherapy, some patients with multifocal, bilobar colorectal liver metastases (CRLM) remain unresectable. These patients may benefit from surgical debulking of liver tumors in combination with chemotherapy compared to chemotherapy alone. (2) Methods: A retrospective study including patients evaluated for curative intent resection of CRLM was performed. Patients were divided into three groups: those who underwent liver resection with recurrence within 6 months (subtotal debulked, SD), those who had the first stage only of a two-stage hepatectomy (partially debulked, PD), and those never debulked (ND). Kaplan-Meier survival curves and log-rank test were performed to assess the median survival of each group. (3) Results: 174 patients underwent liver resection, and 34 patients recurred within 6 months. Of the patients planned for two-stage hepatectomy, 35 underwent the first stage only. Thirty-two patients were never resected. Median survival of the SD, PD, and ND groups was 31 months, 31 months, and 19.5 months, respectively (p = 0.012); (4) Conclusions: Patients who underwent a debulking of CRLM demonstrated a survival benefit compared to patients who did not undergo any surgical resection. This study provides support for the evaluation of intentional debulking versus palliative chemotherapy alone in a randomized trial.

Combined hepatic resection and ablation for high burden of colorectal liver metastases demonstrates safety and durable survival

BACKGROUND

Hepatic resection (HR) and thermal ablation of Colorectal Liver Metastases (CRLM) have each individually demonstrated safety and survival benefit. We sought to provide our experience with the combination of HR + ablation within one operation for patients with multiple CRLM.

METHODS

Review of a single institution database of patients who underwent HR + ablation between 2010 and 2019.

RESULTS

161 patients were identified who underwent HR + ablation for isolated CRLM (mean age: 59, male 63.4%). 125 (77.6%) patients had bilobar disease and 92 (57.1%) patients had ≥5 tumors. 28 (17.4%) patients experienced minor (grade 1 or 2) complications while 20 (12.4%) had grade 3-5 complications. Patients who underwent simultaneous colon resection with HR + ablation had a higher complication rate (22 of 47, 46.8%) than those undergoing HR + ablation only (26 of 114, 22.8%, p = 0.002). Median and 5-year OS for all patients undergoing HR + ablation was 38.2 months and 33.2%, respectively. 5-year hepatic recurrence free survival was 23.5%. Patients with 5 or more tumors demonstrated no difference in median survival compared to those with fewer than 5 tumors (37.0 months vs 38.4 months, p = 0.326).

CONCLUSIONS

In this population of CRLM patients with a relatively high burden of disease, HR + ablation demonstrated an acceptable safety profile as well as durable long-term survival.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Surgeon's Experience May Circumvent Operative Volume in Improving Early Outcomes After Pancreaticoduodenectomy

Introduction Pancreaticoduodenectomy (PD) is a complex procedure with a significant proportion of postoperative complications and improving but notable mortality. PD was the prototype procedure that initiated the lingering debate about the relationship of better operative outcomes when performed at higher-volume centers. This has not translated into practice. Impediments include the absence of a universally accepted definition of a high-volume center among others. Contrary evidence suggests equivalent outcomes for PD at low-volume centers when performed by experienced hepatobiliary surgeons. We reviewed our perioperative outcomes for PD from an earlier period as a low-volume center with an experienced team. Methods A longitudinal study of all PDs completed in our department between 2012 and 2017 was performed. Results A total of 28 PD were performed during this period. Pylorus-preserving PD was performed in 23 patients and classical PD in the remaining. A separate Roux-en-Y loop was used for high-risk pancreatic anastomosis in six cases. The mean patient age was 49.3±12.4 years. The male-to-female ratio was 1.3:1. Preoperative drainage procedures were carried out in 19 patients. The mean serum total bilirubin level was 3.98(±4.5) mg/dL. There was no 90-day mortality. Postoperative complications included wound infection in 10 (36.7%) and respiratory complications in 10 (36.7%) patients. Postoperative bleeding requiring intervention occurred in one patient, and two patients had an anastomotic leak (one pancreatojejunostomy (PJ) and one gastrojejunostomy (GJ)). Delayed gastric emptying (DGE) was noted in three (10.7%) patients. The mean length of hospital stay was 14±7 days. The median overall survival (OS) was 84 months. Conclusion Comparable early outcomes can be achieved at low-volume centers for patients undergoing PD with an experienced team, optimal patient selection, and the ability to rescue for complications.

Predicting Limited Survival After Resection of Synchronous Colorectal Liver Metastases: a Propensity Score Matched Comparison Between The Primary First And The Simultaneous Strategy

BACKGROUND

The best surgical approach to treat synchronous colorectal liver metastases (CRLM) remains unclear. Here, we aimed to identify prognostic factors associated with limited survival comparing patients undergoing primary-first resection (PF) and simultaneous resection (SR) approaches.

METHODS

We retrospectively reviewed clinical data of 217 patients who underwent resection for synchronous CRLMs between January 1, 2011, and December 31, 2021. There were 133 (61.2%) PF resection and 84 (38.8%) SRS. The two groups of patients were compared using propensity score matching (PSM) analysis and cox analysis was performed to identify prognostic factors for overall survival (OS).

RESULTS

After PSM, two groups of 71 patients were compared. Patients undergoing SR had longer operative time (324 ± 104 min vs 250 ± 101 min; p < 0.0001), similar transfusion (33.3% vs 28.1%; p = 0.57), and similar complication rates (35.9% vs 27.2%; p = 0.34) than patients undergoing PF. The median overall survival and 5-year survival rates were comparable (p = 0.94) between patients undergoing PF (48.2 months and 44%) and patients undergoing SR (45.9 months and 30%). Multivariate Cox analysis identified pre-resection elevated CEA levels (HR: 2.38; 95% CI: 1.20-4.70; P = .01), left colonic tumors (HR: 0.34; 95% CI: 0.17-0.68; P = .002), and adjuvant treatment (HR: 0.43; 95% CI: 0.22-0.83; P = .01) as independent prognostic factors for OS.

CONCLUSIONS

In the presence of synchronous CRLM, right colonic tumors, persistent high CEA levels before surgery, and the absence of adjuvant treatment identified patients characterized by a limited survival rate after resection. The approach used (PF vs SR) does not influence short and long-term outcomes.

Radiofrequency ablation in treatment of hepatic metastases of colorectal cancer

Radiofrequency ablation in treatment of hepatic metastases of colorectal cancer

Improved Outcomes of Thermal Ablation for Colorectal Liver Metastases: A 10-Year Analysis from the Prospective Amsterdam CORE Registry (AmCORE)

Background

To analyze long-term oncological outcomes of open and percutaneous thermal ablation in the treatment of patients with colorectal liver metastases (CRLM).

Methods

This assessment from a prospective, longitudinal tumor registry included 329 patients who underwent 541 procedures for 1350 CRLM from January 2010 to February 2021. Three cohorts were formed: 2010–2013 (129 procedures [53 percutaneous]), 2014–2017 (206 procedures [121 percutaneous]) and 2018–2021 (206 procedures [135 percutaneous]). Local tumor progression-free survival (LTPFS) and overall survival (OS) data were estimated using the Kaplan–Meier method. Potential confounding factors were analyzed with uni- and multivariable Cox regression analyses.

Results

LTPFS improved significantly over time for percutaneous ablations (2-year LTPFS 37.7% vs. 69.0% vs. 86.3%, respectively, P < .0001), while LTPFS for open ablations remained reasonably stable (2-year LTPFS 87.1% [2010–2013], vs. 92.7% [2014–2017] vs. 90.2% [2018–2021], P = .12). In the latter cohort (2018–2021), the open approach was no longer superior regarding LTPFS (P = .125). No differences between the three cohorts were found regarding OS (P = .088), length of hospital stay (open approach, P = .065; percutaneous approach, P = .054), and rate and severity of complications (P = .404). The rate and severity of complications favored the percutaneous approach in all three cohorts (P = .002).

Conclusion

Over the last 10 years efficacy of percutaneous ablations has improved remarkably for the treatment of CRLM. Oncological outcomes seem to have reached results following open ablation. Given its minimal invasive character and shorter length of hospital stay, whenever feasible, percutaneous procedures may be favored over an open approach.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00270-022-03152-9.

Parenchyma-sparing strategy and oncological prognosis in patients with colorectal cancer liver metastases

Background

Preliminary study results demonstrated parenchyma-sparing surgery (PSS) as an effective approach which allowed to remove colorectal cancer (CRC) metastatic lesions within the central liver cites and increased the probability of the liver re-resections.

Methods

The prospective analysis re-evaluation of the 185 CRC patients surgical treatment has been performed.

Results

An overall 5-year survival (OS) of the 185 enrolled patients was 43 ± 7%, and the mean and median value for OS was 48.7 ± 1.9% and 55.2 ± 5 (95% CI: 44.4–66.1) months. The 5-year OS for CRC patients whose metastatic lesions were predominantly located within peripheral and central liver segments was 56 ± 8% and 27 ± 9%, respectively (p = 0.08). A 5-year disease-free survival (DFS) rates of patients with peripheral and central liver cites metastatic lesions were 31 ± 7 % and 15 ± 7%, p = 0,12. And the DFS median was 34.2 and 46.5 months for R_1v and R0 cohorts, respectively, p = 0.62.

Conclusions

Parenchyma-sparing surgery should be a priority pathway for complex treatment of patients with deeply located lesions of the right liver lobe.

Trial registration

The study is registered in https://www.researchregistry.com/browse-the-registry#home/registrationdetails/5ed9f60863e9bf0016624456/, no. 5679.

Clinical added value of MRI to CT in patients scheduled for local therapy of colorectal liver metastases (CAMINO): study protocol for an international multicentre prospective diagnostic accuracy study

BACKGROUND

Abdominal computed tomography (CT) is the standard imaging method for patients with suspected colorectal liver metastases (CRLM) in the diagnostic workup for surgery or thermal ablation. Diffusion-weighted and gadoxetic-acid-enhanced magnetic resonance imaging (MRI) of the liver is increasingly used to improve the detection rate and characterization of liver lesions. MRI is superior in detection and characterization of CRLM as compared to CT. However, it is unknown how MRI actually impacts patient management. The primary aim of the CAMINO study is to evaluate whether MRI has sufficient clinical added value to be routinely added to CT in the staging of CRLM. The secondary objective is to identify subgroups who benefit the most from additional MRI.

METHODS

In this international multicentre prospective incremental diagnostic accuracy study, 298 patients with primary or recurrent CRLM scheduled for curative liver resection or thermal ablation based on CT staging will be enrolled from 17 centres across the Netherlands, Belgium, Norway, and Italy. All study participants will undergo CT and diffusion-weighted and gadoxetic-acid enhanced MRI prior to local therapy. The local multidisciplinary team will provide two local therapy plans: first, based on CT-staging and second, based on both CT and MRI. The primary outcome measure is the proportion of clinically significant CRLM (CS-CRLM) detected by MRI not visible on CT. CS-CRLM are defined as liver lesions leading to a change in local therapeutical management. If MRI detects new CRLM in segments which would have been resected in the original operative plan, these are not considered CS-CRLM. It is hypothesized that MRI will lead to the detection of CS-CRLM in ≥10% of patients which is considered the minimal clinically important difference. Furthermore, a prediction model will be developed using multivariable logistic regression modelling to evaluate the predictive value of patient, tumor and procedural variables on finding CS-CRLM on MRI.

DISCUSSION

The CAMINO study will clarify the clinical added value of MRI to CT in patients with CRLM scheduled for local therapy. This study will provide the evidence required for the implementation of additional MRI in the routine work-up of patients with primary and recurrent CRLM for local therapy.

TRIAL REGISTRATION

The CAMINO study was registered in the Netherlands National Trial Register under number NL8039 on September 20th 2019.

Short- and long-term outcomes of hepatectomy combined with intraoperative radiofrequency ablation for patients with multiple primarily unresectable colorectal liver metastases: a propensity matching analysis

BACKGROUND

Hepatectomy combined with intraoperative radiofrequency ablation (IORFA) is a strategy to eliminate all tumors in patients with multiple colorectal liver metastases (CRLM). This study aimed to evaluate the surgical and oncological outcomes of hepatectomy + IORFA for multiple unresectable CRLM.

METHODS

We included patients who underwent combined hepatectomy and IORFA for multiple unresectable CRLM (n = 67) or hepatectomy alone (n = 268) for CRLM. Patients were matched in a 1:1 propensity score analysis to compare the short- and long-term outcomes between groups.

RESULTS

Patients in hepatectomy + IORFA group had a median number of 10 liver lesions. Postoperative morbidity and the rate of major complications was similar between groups (P = 0.362, P = 1.000). The median overall survival (OS), progression free survival (PFS) and hepatic recurrence free survival (HRFS) was similar between groups (3-year OS: 54.2% versus 60.9%, P = 0.389; 3-year PFS: 7.9% versus 19.6%, P = 0.148; 3-year HRFS: 16.7% versus 31.5%, P = 0.202). Re-hepatectomy or radiofrequency ablation was used to treat 47.5% of hepatic recurrences, and the median OS was significantly higher than for patients treated with systemic treatment alone (P < 0.001).

CONCLUSIONS

Combining hepatectomy and IORFA could provide comparable survival rates for patients with multiple unresectable CRLM compared to those with resectable CRLM treated with hepatectomy alone.

Metastatic disease to the liver: Locoregional therapy strategies and outcomes

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

Comparison of intrahepatic progression patterns of hepatocellular carcinoma and colorectal liver metastases following CT-guided high dose-rate brachytherapy

Introduction:

Given the metachronous and multifocal occurrence of hepatocellular carcinoma (HCC) and colorectal cancer metastases in the liver (CRLM), this study aimed to compare intrahepatic progression patterns after computed tomography (CT)-guided high dose-rate brachytherapy.

Patients and methods:

This retrospective analysis included 164 patients (114 HCC, 50 CRLM) treated with brachytherapy between January 2016 and January 2018. Patients received multiparametric magnetic resonance imaging (MRI) before, and about 8 weeks after brachytherapy, then every 3 months for the first, and every 6 months for the following years, until progression or death. MRI scans were assessed for local or distant intrahepatic tumor progression according to RECIST 1.1 and electronic medical records were reviewed prior to therapy. The primary endpoint was progression-free survival (PFS). Specifically, local and distant intra-hepatic PFS were assessed to determine differences between the intrahepatic progression patterns of HCC and CRLM. Secondary endpoints included the identification of predictors of PFS, time to progression (TTP), and overall survival (OS). Statistics included Kaplan–Meier analysis and univariate and multivariate Cox regression modeling.

Results:

PFS was longer in HCC [11.30 (1.33–35.37) months] than in CRLM patients [8.03 (0.73–19.80) months, p = 0.048], respectively. Specifically, local recurrence occurred later in HCC [PFS: 36.83 (1.33–40.27) months] than CRLM patients [PFS: 12.43 (0.73–21.90) months, p = 0.001]. In contrast, distant intrahepatic progression occurred earlier in HCC [PFS: 13.50 (1.33–27.80) months] than in CRLM patients [PFS: 19.80 (1.43–19.80) months, p = 0.456] but without statistical significance. Multivariate Cox regression confirmed tumor type and patient age as independent predictors for PFS.

Conclusion:

Brachytherapy proved to achieve better local tumor control and overall PFS in patients with unresectable HCC as compared to those with CRLM. However, distant progression preceded local recurrence in HCC. As a result, these findings may help design disease-specific surveillance strategies and personalized treatment planning that highlights the strengths of brachytherapy. They may also help elucidate the potential benefits of combinations with other loco-regional or systemic therapies.

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

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Imaging and Image-Guided Thermal Ablation for Oligometastatic Colorectal Cancer Liver Disease

Colorectal cancer affects more than 1 million people worldwide, and half of this population develops liver metastases. Image-guided thermal ablation is an acceptable local therapy for the management of oligometastatic colorectal cancer liver disease, in patients who are noneligible for surgery, or present with recurrence after hepatectomy. Continuous technological evolutions, understanding of tumor variability through disease biology and genetics, and optimization of ablation parameters with ablation margin assessment have allowed patients with resectable small-volume disease to be treated by thermal ablation with curative intent. The growing role of imaging and image guidance in thermal ablation for patient selection, procedure planning, tumor targeting, and assessment of technical success is discussed in this article.

Long-term outcome of Stereotactic Body Radiation Therapy for patient with unresectable liver metastases from colorectal cancer

PURPOSE

To investigate clinical outcome and predicting factors of local failures in patients with colorectal cancer treated for unresectable liver metastases with stereotactic body radiation therapy (SBRT).

METHODS AND MATERIALS

We restrospectively reviewed the medical records of 67 patients treated with the Cyberknife SBRT system for 99 hepatic metastases between January 2007 and December 2015 in our center. In total, 37.5 to 54.0Gy in 3 to 5 fractions were prescribed to the 80% isodose line. Local control (LC), intrahepatic progression incidence, Progression-Free Survival (PFS), Overall Survival (OS) and toxicity were evaluated.

RESULTS

The median follow-up was 47 months (IQR, 28-59 months). The median OS was 53 months, the 2-year OS and PFS rates were 81.4% and 54.0%. The 1- and 2-year LC rates were 86.6% and 72.4%. In the multivariate analysis, the degree of differentiation was the only prognostic factor for LC (HR 0.31, 95% CI, 0.10-0.98, P=0.046). Margin expansion>5mm was not associated with a better LC (HR 0.72, 95% CI, 0.38-1.37, P=0.317). Performans Status≥2 (HR 3.27, 95% CI, 1.07-9.98, P=0.038), chemotherapy for metastases before SBRT (HR 0.36, 95% CI, 0.18-0.75, P=0.006) and regional lymph node at diagnosis (HR 2.19, 95% CI, 1.09-4.43, P=0.029) were independent prognostic factors for OS. We report 2 cases of grade≥3 toxicity (3.0%) - one grade 3 acute nausea and one grade 3 late gastric ulcer.

CONCLUSION

Stereotactic body radiation therapy is an effective and well-tolerated treatment that allow high LC for liver metastases from colorectal cancer during the first two years. A prescription dose of 45Gy in 3 fractions to the 80% isodose line with a risk adapted schedule to respect Organ At Risk constraints allows a low rate of toxicity.

The role of associating liver partition and portal vein ligation for staged hepatectomy in the management of patients with colorectal liver metastasis

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) approach emerged as a promising surgical strategy for rapid and large hypertrophy of the future liver remnant (FLR) when a major liver resection is necessary. Colorectal liver metastasis (CRLM) is their main indication. However, the promising results published so far, are very difficult to interpret since they usually focus on the technique and not on the underlying disease. Moreover, they are usually made up of complex populations, which received different chemotherapy schemes, with the ALPPS technical variations implemented over time and without consistent long-term follow-up results as well. Whereby, its role in CRLM should be analyzed as carefully as possible to indicate and select the best candidates who will benefit the most from this approach. We conducted a computerized search using PubMed and Google Scholar for reports published so far, using mesh headings and keywords related to the ALPPS and CRLM.

Modern therapeutic approaches for the treatment of malignant liver tumours

Malignant liver tumours include a wide range of primary and secondary tumours. Although surgery remains the mainstay of curative treatment, modern therapies integrate a variety of neoadjuvant and adjuvant strategies and have achieved dramatic improvements in survival. Extensive tumour loads, which have traditionally been considered unresectable, are now amenable to curative treatment through systemic conversion chemotherapies followed by a variety of interventions such as augmentation of the healthy liver through portal vein occlusion, staged surgeries or ablation modalities. Liver transplantation is established in selected patients with hepatocellular carcinoma but is now emerging as a promising option in many other types of tumour such as perihilar cholangiocarcinomas, neuroendocrine or colorectal liver metastases. In this Review, we summarize the available therapies for the treatment of malignant liver tumours, with an emphasis on surgical and ablative approaches and how they align with other therapies such as modern anticancer drugs or radiotherapy. In addition, we describe three complex case studies of patients with malignant liver tumours. Finally, we discuss the outlook for future treatment, including personalized approaches based on molecular tumour subtyping, response to targeted drugs, novel biomarkers and precision surgery adapted to the specific tumour.

Simultaneous colorectal and parenchymal-sparing liver resection for advanced colorectal carcinoma with synchronous liver metastases: Between conventional and mini-invasive approaches

The optimal timing of surgery in case of synchronous presentation of colorectal cancer and liver metastases is still under debate. Staged approach, with initial colorectal resection followed by liver resection (LR), or even the reverse, liver-first approach in specific situations, is traditionally preferred. Simultaneous resections, however, represent an appealing strategy, because may have perioperative risks comparable to staged resections in appropriately selected patients, while avoiding a second surgical procedure. In patients with larger or multiple synchronous presentation of colorectal cancer and liver metastases, simultaneous major hepatectomies may determine worse perioperative outcomes, so that parenchymal-sparing LR should represent the most appropriate option whenever feasible. Mini-invasive colorectal surgery has experienced rapid spread in the last decades, while laparoscopic LR has progressed much slower, and is usually reserved for limited tumours in favourable locations. Moreover, mini-invasive parenchymal-sparing LR is more complex, especially for larger or multiple tumours in difficult locations. It remains to be established if simultaneous resections are presently feasible with mini-invasive approaches or if we need further technological advances and surgical expertise, at least for more complex procedures. This review aims to critically analyze the current status and future perspectives of simultaneous resections, and the present role of the available mini-invasive techniques.

Image-Guided Thermal Ablation for Colorectal Liver Metastases

Image-guided percutaneous thermal ablation is a widely acceptable local therapy for patients with colorectal liver metastases who are noneligible for surgery or present with recurrence after hepatectomy. The increasing knowledge of factors that affect oncologic outcomes has allowed selected patients with resectable small volume colorectal liver metastases to be treated by thermal ablation with curative intent. The continuous technological evolutions in imaging and image-guidance and the wide implementation of microwave ablation that overcomes most of the limitations of radiofrequency ablation have contributed to this paradigm shift. The importance of patient selection, ablation margin evaluation, and confirmation of complete tumor ablation (A0) are discussed in this article.

Laparoscopic Versus Open Thermal Ablation of Colorectal Liver Metastases: A Propensity Score-Based Analysis of Local Control of the Ablated Tumors

BACKGROUND

Laparoscopic ablation (LA) of colorectal liver metastases (CRLMs) is frequently performed in combination with laparoscopic liver resection or as a stand-alone procedure. However, LA is technically demanding and whether the results are comparable with those of open ablation (OA) has not been determined to date. This study compared the effectiveness of LA and OA in achieving local tumor control of CRLMs.

METHODS

Patients undergoing LA or OA of CRLMs at Ghent University Hospital between June 2007 and February 2018 were identified from a prospective database. Lesions treated by LA and OA were matched 1:1 using a propensity score based on lesions (liver segment, size, deepness, proximity to a vessel), patients, and procedural characteristics. Ablation sites were followed up with computed-tomography or magnetic resonance imaging to assess the completeness of the ablation and ablation-site recurrence (ASR). Analysis of ASR was performed with the Kaplan-Meier method and Cox regression.

RESULTS

In this study, 163 patients underwent the surgical ablation (78 LA, 85 OA) of 333 CRLMs (143 LA, 190 OA). After matching, 220 lesions (110 LA, 110 OA) were analyzed. Ablation was complete in 93.7% (LA) and 97.3% (OA) of the sites (p = 0.195). No difference in ASR was observed (p = 0.351), with a cumulative risk of ASR at 12 months of 9.1% (LA) and 8.2% (OA). After multivariable analysis, ASR was confirmed to be independent of the surgical approach.

CONCLUSION

The findings showed that LA and OA achieve a comparable local control of CRLMs. This result further supports the adoption of a laparoscopic approach for the treatment of CRLMs.

Is progression in the future liver remnant a contraindication for second-stage hepatectomy?

BACKGROUND

Two-stage hepatectomy (TSH) strategy is used to treat patients with bilobar colorectal liver metastasis (CLM). However, many patients do not undergo the second hepatectomy owing to disease progression in the future liver remnant (FLR) after portal vein embolization (PVE). This study aimed to assess the impact of disease progression in the FLRs of patients who completed the first hepatectomy.

METHODS

68 consecutive patients underwent the first hepatectomy followed by PVE. Six patients (9%) dropped out after the PVE (two-stage failed [TSF] group) because of unresectable hepatic or general disease progression. Seventeen patients (25%) completed their second hepatectomy despite disease progression in the FLR (new CLM [nCLM] group) as it was considered resectable, while 45 patients (66%) underwent the second hepatectomy (control group).

RESULTS

The 5-year overall survival rates in the TSF, nCLM, and control groups were 0%, 7%, and 60%, respectively (P < 0.001). The median overall survival times between the TSF and nCLM groups were 26 months and 42 months (P = 0.005). Patients in the nCLM group whose hepatic disease progression was detected preoperatively versus intraoperatively had comparable survival rates.

CONCLUSION

Resectable hepatic disease progression in the FLR after PVE should not be considered a contraindication for the second hepatectomy.

Thermal Ablation of Metastatic Colon Cancer to the Liver

Colorectal cancer (CRC) is responsible for approximately 10% of cancer-related deaths in the Western world. Liver metastases are frequently seen at the time of diagnosis and throughout the course of the disease. Surgical resection is often considered as it provides long-term survival; however, few patients are candidates for resection. Percutaneous ablative therapies are also used in the management of this patient population. Different thermal ablation (TA) technologies are available including radiofrequency ablation, microwave ablation (MWA), laser, and cryoablation. There is growing evidence about the role of interventional oncology and image-guided percutaneous ablation in the management of metastatic colorectal liver disease. This article aims to outline the technical considerations, outcomes, and rational of TA in the management of patients with CRC liver metastases, focusing on the emerging role of MWA.

Colorectal liver metastases: An update on multidisciplinary approach

Liver metastasis is the commonest form of distant metastasis in colorectal cancer. Selection criteria for surgery and liver-directed therapies have recently been extended. However, resectability remains poorly defined. Tumour biology is increasingly recognized as an important prognostic factor; hence molecular profiling has a growing role in risk stratification and management planning. Surgical resection is the only treatment modality for curative intent. The most appropriate surgical approach is yet to be established. The primary cancer and the hepatic metastasis can be removed simultaneously or in a two-step approach; these two strategies have comparable long-term outcomes. For patients with a limited future liver remnant, portal vein embolization, combined ablation and resection, and associating liver partition and portal vein ligation for staged hepatectomy have been advocated, and each has their pros and cons. The role of neoadjuvant and adjuvant chemotherapy is still debated. Targeted biological agents and loco-regional therapies (thermal ablation, intra-arterial chemo- or radio-embolization, and stereotactic radiotherapy) further improve the already favourable results. The recent debate about offering liver transplantation to highly selected patients needs validation from large clinical trials. Evidence-based protocols are missing, and therefore optimal management of hepatic metastasis should be personalized and determined by a multi-disciplinary team.

Simultaneous curative resection of double colorectal carcinoma with synchronous bilobar liver metastases

Synchronous colorectal carcinoma (SCRC) indicates more than one primary colorectal carcinoma (CRC) discovered at the time of initial presentation, accounts for 3.1%-3.9% of CRC, and may occur either in the same or in different colorectal segments. The accurate preoperative diagnosis of SCRC is difficult and diagnostic failures may lead to inappropriate treatment and poorer prognosis. SCRC requires colorectal resections tailored to individual patients, based on the number, location, and stage of the tumours, from conventional or extended hemicolectomies to total colectomy or proctocolectomy, when established predisposing conditions exist. The overall perioperative risks of surgery for SCRC seem to be higher than for solitary CRC. Simultaneous colorectal and liver resection represents an appealing surgical strategy in selected patients with CRC and synchronous liver metastases (CRLM), even though the cumulative risks of the two procedures need to be adequately evaluated. Simultaneous resections have the noticeable advantage of avoiding a second laparotomy, give the opportunity of an earlier initiation of adjuvant therapy, and may significantly reduce the hospital costs. Because an increasing number of recent studies have shown good results, with morbidity, perioperative hospitalization, and mortality rates comparable to staged resections, simultaneous procedures can be selectively proposed even in case of complex colorectal resections, including those for SCRC and rectal cancer. However, in patients with multiple bilobar CRLM, major hepatectomies performed simultaneously with colorectal resection have been associated with significant perioperative risks. Conservative or parenchymal-sparing hepatectomies reduce the extent of hepatectomy while preserving oncological radicality, and may represent the best option for selected patients with multiple CRLM involving both liver lobes. Parenchymal-sparing liver resection, instead of major or two-stage hepatectomy for bilobar disease, seemingly reduces the overall operative risk of candidates to simultaneous colorectal and liver resection, and may represent the most appropriate surgical strategy whenever possible, also for patients with advanced SCRC and multiple bilobar liver metastases.

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.

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.

Radiofrequency ablation is beneficial in simultaneous treatment of synchronous liver metastases and primary colorectal cancer

Background

In patients with resectable synchronous colorectal liver metastases (CRLM), either two-staged or simultaneous resections of the primary tumor and liver metastases are performed. Data on radiofrequency ablation (RFA) for the treatment of CRLM during a simultaneous procedure is lacking. The primary aim was to analyze short-term and long-term outcome of RFA in simultaneous treatment. A secondary aim was to compare simultaneous resection with the colorectal-first approach.

Methods

Retrospective analysis of 241 patients with colorectal cancer and synchronous CRLM between 2000–2016. Median follow-up was 36.1 months (IQR 18.2–58.8 months). A multivariable analysis was performed to analyze the postoperative morbidity, using the comprehensive complication index. A propensity matched analysis was performed to compare survival rates.

Results

In multivariable analysis, the best predictor of lower complication severity was treatment with RFA (p = 0.040). Higher complication rates were encountered in patients who underwent an abdominoperineal resection (p = 0.027) or age > 60 years (p = 0.022). The matched analysis showed comparable overall survival in RFA treated patients versus patients undergoing a liver resection with a five year overall survival of 39.4% and 37.5%, respectively (p = 0.782). In a second matched analysis, 5-year overall survival rates in simultaneously treated patients (43.8%) was comparable to patients undergoing the colorectal first approach (43.0%, p = 0.223).

Conclusions

RFA treatment of CRLM in simultaneous procedures is associated with a lower complication severity and non-inferior oncological outcome as compared to partial liver resection. RFA should be considered a useful alternative to liver resection.

Is Enhanced One-Stage Hepatectomy a Safe and Feasible Alternative to the Two-Stage Hepatectomy in the Setting of Multiple Bilobar Colorectal Liver Metastases? A Comparative Analysis between Two Pioneering Centers

BACKGROUND

Two-stage hepatectomy (TSH) is the present standard for multiple bilobar colorectal metastases (CLM). As alternative, ultrasound-guided one-stage hepatectomy (E-OSH) has been proposed even for deep-located nodules to compare TSH and E-OSH.

METHODS

All consecutive TSH at the Paul Brousse Hospital and E-OSH at the Humanitas Research Hospital were considered. The inclusion criteria were ≥6 CLM, ≥3 CLM in the left liver, and ≥1 lesion with vascular contact. A total of 74 TSH and 35 E-OSH were compared.

RESULTS

The 2 groups had similar characteristics. Drop-out rate of TSH was 40.5%. In comparison with the cumulated hepatectomies of TSH, E-OSH had lower blood loss (500 vs. 1,100 mL, p = 0.009), overall morbidity (37.1 vs. 70.5%, p = 0.003), severe morbidity (14.3 vs. 36.4%, p = 0.04), and liver-specific morbidity (22.9 vs. 40.9%, p = 0.02). R0 resection rate was similar between groups. E-OSH and completed TSH had similar overall survival (5-year 38.2 vs. 31.8%), recurrence-free survival (3-year 17.6 vs. 17.7%), and recurrence sites.

CONCLUSIONS

E-OSH is a safe alternative to TSH for multiple bilobar deep-located CLM. Whenever feasible, E-OSH should even be considered the preferred option because it has excellent safety and oncological outcomes equivalent to completed TSH, without the drop-out risk.

Surgical Treatment of Metastatic Colorectal Cancer

Surgical treatment of metastatic colorectal cancer offers a chance for cure or prolonged survival, particularly for those with more favorable prognostic factors and limited tumor burden. The treatment plan requires multidisciplinary evaluation because multiple therapy options exist. Advanced surgical techniques, adjuncts to resection, and modern chemotherapy all contribute to best outcomes for patients with hepatic metastases. Although cure is less common for patients with metastasis to lung or peritoneum, surgical resection for the former and cytoreduction and intraperitoneal chemotherapy for the latter may help to achieve cancer control in selected patients.

Bilobar versus unilobar multiple colorectal liver metastases: a propensity score analysis of surgical outcomes and recurrence patterns

BACKGROUND

Bilobar multiple colorectal liver metastases (MCLM) are often considered incurable or associated with a poor prognosis even after R0 resection. This study was designed to compare the long-term outcomes and recurrence patterns after one-stage resection in patients with bilobar versus unilobar MCLM.

METHODS

The records of patients undergoing parenchymal-sparing intent hepatectomy between 1994 and 2015 were reviewed. Survival and recurrence patterns were analyzed by propensity score matching.

RESULTS

The study population included 140 patients: 81 patients with bilobar MCLM versus 59 patients with unilobar MCLM. In the propensity score matching analysis (bilobar, n = 35 vs. unilobar, n = 35), the short-term outcomes did not differ between the two groups. Five-year overall survival (54.8% in bilobar vs. 51.2% in unilobar; P = 0.388) and recurrence-free survival (28.5% in bilobar vs. 36.2% in unilobar; P = 0.261) also did not differ. No significant differences were found in liver-only recurrence (22.9% in bilobar vs. 25.7% in unilobar; P = 1.000) and other recurrence patterns.

CONCLUSIONS

The clearance of bilobar MCLM by one-stage resection of parenchymal-sparing intent provided comparable long-term survival to unilobar MCLM.

Determination of the electrical conductivity of human liver metastases: impact on therapy planning in the radiofrequency ablation of liver tumors

Background Radiofrequency ablation is used to induce thermal necrosis in the treatment of liver metastases. The specific electrical conductivity of a liver metastasis has a distinct influence on the heat formation and resulting tumor ablation within the tissue. Purpose To examine the electrical conductivity σ of human colorectal liver metastases and of tumor-free liver tissue in surgical specimens. Material and Methods Surgical specimens from patients with resectable colorectal liver metastases were used for measurements (size of metastases <30 mm). A four-needle measuring probe was used to determine the electrical conductivity σ of human colorectal liver metastasis (n = 8) and tumor-free liver tissue (n = 5) in a total of five patients. All measurements were performed at 470 kHz, which is the relevant frequency for radiofrequency ablation. The tissue temperature was also measured. Hepatic resections were performed in accordance with common surgical standards. Measurements were performed in the operating theater immediately after resection. Results The median electrical conductivity σ was 0.57 S/m in human colorectal liver metastases at a median temperature of 35.1℃ and 0.35 S/m in tumor-free liver tissue at a median temperature of 34.9℃. The electrical conductivity was significantly higher in tumor tissue than in tumor-free liver tissue ( P = 0.005). There were no differences in tissue temperature between the two groups ( P = 0.883). Conclusion The electrical conductivity is significantly higher in human colorectal liver metastases than in tumor-free liver tissue at a frequency of 470 kHz.

Parenchymal-sparing hepatectomies (PSH) for bilobar colorectal liver metastases are associated with a lower morbidity and similar oncological results: a propensity score matching analysis

OBJECTIVE

The aim of this study is to evaluate whether a parenchymal-sparing strategy provides similar results in terms of morbidity, mortality, and oncological outcome of non-PSH hepatectomies in a propensity score matched population (PSMP) in case of multiple (>3) bilobar colorectal liver metastases (CLM).

BACKGROUND

The surgical treatment of bilobar liver metastasis is challenging due to the necessity to achieve complete resection margins and a sufficient future remnant liver. Two approaches are adaptable as follows: parenchymal-sparing hepatectomies (PSH) and extended hepatectomies (NON-PSH).

METHODS

A total of 3036 hepatectomies were analyzed from a multicentric retrospective cohort of hepatectomies. Patients were matched in a 1:1 propensity score analysis in order to compare PSH versus NON-PSH resections.

RESULTS

PSH was associated with a lower number of complications (≥1) (25% vs. 34%, p = 0.04) and a lower grade of Dindo-Clavien III and IV (10 vs. 16%, p = 0.03). Liver failure was less present in PSH (2 vs. 7%, p = 0.006), with a shorter ICU stay (0 day vs. 1 day, p = 0.004). No differences were demonstrated in overall and disease-free survival.

CONCLUSION

In conclusion, PSH resection for bilobar multiple CLMs represents a valid alternative to NON-PSH resection in selected patients with a reduced morbidity and comparable oncological results.