Survival Outcomes After Portal Vein Embolization and Liver Resection Compared With Liver Transplant for Patients With Extensive Colorectal Cancer Liver Metastases

EASL Clinical Practice Guidelines on liver transplantation

Liver transplantation (LT) is an established life-saving procedure. The field of LT has changed in the past 10 years from several perspectives, with the expansion of indications, transplantation of patients with acute-on-chronic liver failure, evolution of transplant oncology, the use of donations after cardiac death, new surgical techniques, and prioritisation of recipients on the waiting list. In addition, the advent of organ perfusion machines, the recognition of new forms of rejection, and the attention paid to the transition from paediatric to adult patients, have all improved the management of LT recipients. The purpose of the EASL guidelines presented here is not to cover all aspects of LT but to focus on developments since the previous EASL guidelines published in 2016.

Translating efficacy of liver transplantation in liver-limited metastatic colorectal cancer into clinical practice: the TransMet trial

Pioneer studies suggested that liver transplantation (LT) has the potential to provide long-term survival in patients with liver-limited metastatic colorectal cancer (mCRC) not amenable for surgery of metastases. Evidence, however, was limited to single-arm studies with few patients enrolled and suboptimal selection criteria, with concerns over access to organ availability overcoming the potential efficacy of LT in this setting. Recently, 5-year survival rates with chemotherapy followed by LT (73%) compared with chemotherapy alone (9%) have been demonstrated by the randomized TransMet trial, enrolling 94 definitively unresectable strictly selected liver-limited mCRC patients. These findings should now prompt clinical oncologists to reconsider LT as a valuable option for unresectable liver-limited mCRC patients meeting TransMet criteria, and transplantation agencies to adapt their policies of access to organ donation.

Liver transplantation for tumor entities

PURPOSE OF REVIEW

Tumor entities represent an increasing indication for liver transplantation (LT). This review addresses the most contentious indications of LT in transplant oncology.

RECENT FINDINGS

Patient selection based on tumor biology in LT for colorectal cancer liver metastases (CRLM) demonstrated promising long-term outcomes and preserved quality of life despite high recurrence rates. In selected cases, LT for intrahepatic cholangiocarcinoma (iCCA) is feasible, with acceptable survival even in high-burden cases responsive to chemotherapy. LT following a strict neoadjuvant protocol for perihilar cholangiocarcinoma (pCCA) resulted in long-term outcomes consistently surpassing benchmark values, and potentially outperforming liver resection.

SUMMARY

While preliminary results are promising, prospective trials are crucial to define applications in routine clinical practice. Molecular profiling and targeted therapies pave the way for personalized approaches, requiring evolving allocation systems for equitable LT access.

Catheter-Directed Ionic Liquid Embolic Agent for Rapid Portal Vein Embolization, Segmentectomy, and Bile Duct Ablation

Embolic materials currently in use for portal vein embolization (PVE) do not treat the tumor, which poses a risk for tumor progression during the interval between PVE and surgical resection. Here, is developed an ionic-liquid-based embolic material (LEAD) for portal vein embolization, liver ablation, and drug delivery. LEAD is optimized and characterized for diffusivity, X-ray visibility, and cytotoxicity. In the porcine renal embolization model, LEAD delivered from the main renal artery reached vasculature down to 10 microns with uniform tissue ablation and delivery of small and large therapeutics. In non-survival and survival porcine experiments, successful PVE is achieved in minutes, leading to the expected chemical segmentectomy, and delivery of a large protein drug (i.e., Nivolumab) with LEAD. In cholangiocarcinoma mouse tumor models and in ex vivo human tumors, LEAD consistently achieved an effective ablation and wide drug distribution. Furthermore, various strains of drug-resistant patient-derived bacteria showed significant susceptibility to LEAD, suggesting that LEAD may also prevent infectious complications resulting from tissue ablation. With its capabilities to embolize, ablate, and deliver therapeutics, ease of use, and a high safety profile demonstrated in animal studies, LEAD offers a potential alternative to tumor ablation with or without PVE for FLR growth.

Exploration of the Molecular Mechanism of Curcuma aromatica Salisb's Anticolorectal Cancer Activity via the Integrative Approach of Network Pharmacology and Experimental Validation

Curcuma aromatica Salisb (Cur), a well-known herbal medicine, has a wide spectrum of anti-inflammatory, anticarcinogenic, and antioxidant activities. However, the roles of its active compounds and potential mechanisms in colorectal cancer remain unknown. This research utilized network pharmacology and experimental validation to explore the possible mechanisms by which Cur protects against colorectal cancer. The active compounds of Cur and related genes for colorectal cancer were obtained from public databases. The DrugBank database was used to search for anticolorectal cancer drugs licensed through the FDA and their targets, and a "drug-component-target" relationship network was created using the Cytoscape program. The String database produced the PPI network. The ability of these active ingredients to bind to core targets was confirmed by molecular docking using AutoDock Vina. Cell and animal experiments were then carried out. A total of 274 targets were obtained from Cur, 49 of which were potential therapeutic targets. Four key targets, PTGS2, AKT1, TP53, and estrogen receptor 1 (ESR1), were screened via the PPI network and the FDA drug-target network. Molecular docking results revealed that Cur had strong binding abilities to these targets. In vivo and in vitro experiments demonstrated that Cur suppressed the development of colorectal cancer by regulating its targets (PTGS2, AKT1, TP53, and ESR1), which play crucial roles in promoting apoptosis and suppressing cell proliferation, migration, and invasion. Collectively, Cur protects against colorectal cancer by regulating the AKT1/PTGS2/ESR1 and P53 pathways, which lays the groundwork for further research and clinical applications of Cur in colorectal cancer therapy.

Liver Transplantation for Nonresectable Colorectal Liver Metastases (CRLM)

Transplantation represents the most radical locoregional therapy through removal of the liver, associated vasculature and locoregional lymph nodes, and replacing it with an allograft. Recent evidence has demonstrated that transplantation for unresectable CRLM is feasible with acceptable post-transplant outcomes in a highly selected cohort of patients. Controversy exists regarding whether transplantation is an appropriate treatment for such patients, due to concerns regarding disease recurrence in the transplanted graft in an immunosuppressed recipient along with utilising a donor liver which are in short supply. Expanding the indications for liver transplantation may also limit access for other patients with end-stage liver disease having ethical implications due to the effect of increasing the waiting list. In this review, we summarise the current evidence for liver transplantation in patients with nonresectable CRLM and highlight unresolved controversies and future directions for this type of treatment.

Liver transplantation as an alternative for the treatment of non-resectable liver colorectal cancer: Advancing the therapeutic algorithm

Colorectal cancer is a leading cause of cancer-related mortality, with nearly half of the affected patients developing liver metastases. For three decades, liver resection (LR) has been the primary curative strategy, yet its applicability is limited to about 20% of cases. Liver transplantation (LT) for unresectable metastases was attempted unsuccessfully in the 1990s, with high rates of perioperative death and recurrence. There is now more interest in this strategy due to improvements in systemic therapies and surgical techniques. A significant study conducted by the Oslo group showed that patients receiving liver transplants had a 60% chance of survival after five years. Significantly better results have been achieved by using advanced imaging for risk stratification and further refining selection criteria, especially in the Norvegian SECA trials. This review carefully charts the development and history of LT as a treatment option for colorectal cancer liver metastases. The revolutionary path from the early days of exploratory surgery to the current situation of cautious optimism is traced, highlighting the critical clinical developments and improved patient selection standards that have made LT a potentially curative treatment for such challenging very well selected cases.

Molecular Mechanism of Salvia miltiorrhiza in the Treatment of Colorectal Cancer Based on Network Pharmacology and Molecular Docking Technology

Purpose

This study aimed to investigate the effect of Salvia miltiorrhiza on colorectal cancer, as well as the mechanisms involved.

Methods

The active compounds of Salvia miltiorrhiza and the associated genes in colorectal cancer were sourced from publicly available databases. Targets associated with colorectal cancer were identified by searching the GeneCards and OMIM databases. Subsequently, the Cytoscape 3.6.0 software was employed to create a regulatory network that illustrates the relationships among active ingredients, colorectal cancer, and their corresponding targets. The String database was utilized to generate a PPI network. Molecular docking studies, conducted with AutoDock Vina, verified the binding capabilities of these active components to core targets. The findings from network pharmacology analysis were corroborated through in vitro experiments.

Results

In this study, we identified 39 active components derived from Salvia miltiorrhiza that are predicted to target 544 genes associated with colorectal cancer through network pharmacology. Through a combined analysis of network pharmacology, we isolated three key targets: SRC, IL6, and INS. Molecular docking results convincingly demonstrated Salvia miltiorrhiza's strong binding affinity to these targets. Additionally, in vitro experiments confirmed that Salvia miltiorrhiza effectively inhibited the progression of colorectal cancer via regulating the INS/SRC/IL6 pathway.

Conclusion

Salvia miltiorrhiza emerges as a compelling herbal intervention for colorectal cancer. This study lays the foundation for potential future clinical trials assessing the efficacy of Salvia miltiorrhiza in the management of colorectal cancer.

Transplant oncology - Current indications and strategies to advance the field

Liver transplantation (LT) was originally described by Starzl as a promising strategy to treat primary malignancies of the liver. Confronted with high recurrence rates, indications drifted towards non-oncologic liver diseases with LT finally evolving from a high-risk surgery to an almost routine surgical procedure. Continuously improving outcomes following LT and evolving oncological treatment strategies have driven renewed interest in transplant oncology. This is not only reflected by constant refinements to the criteria for LT in patients with HCC, but especially by efforts to expand indications to other primary and secondary liver malignancies. With new patient-centred oncological treatments on the rise and new technologies to expand the donor pool, the field has the chance to come full circle. In this review, we focus on the concept of transplant oncology, current indications, as well as technical and ethical aspects in the context of donor organs as precious resources.

The High Incidence of Occult Carcinoma in Total Hepatectomy Specimens of Patients Treated for Unresectable Colorectal Liver Metastases With Liver Transplant

OBJECTIVE

To describe the rate of occult carcinoma deposits in total hepatectomy specimens from patients treated with liver transplant (LT) for colorectal liver metastases (CRLM).

BACKGROUND

Previous studies have shown that patients with CRLM treated with systemic therapy demonstrate a high rate of complete radiographic response or may have disappearing liver metastases. However, this does not necessarily translate into a complete pathologic response, and residual invasive cancer may be found in up to 80% of the disappearing tumors after resection.

METHODS

Retrospective review of 14 patients who underwent LT for CRLM, at 2 centers. Radiographic and pathologic correlation of the number of tumors and their viability before and after LT was performed.

RESULTS

The median (interquartile range) number of tumors at diagnosis was 11 (4-23). The median number of chemotherapy cycles was 24 (16-37). Hepatic artery infusion was used in 5 patients (35.7%); 6 (42.9%) underwent surgical resection, and 5 (35.7%) received locoregional therapy. The indication for LT was unresectability in 8 patients (57.1%) and liver failure secondary to oncologic treatment in the remaining 6 (42.9%). Before LT, 7 patients (50%) demonstrated fluorodeoxyglucose-avid tumors and 7 (50%) had a complete radiographic response. Histopathologically, 11 patients (78.6%) had a viable tumor. Nine (64.2%) of the 14 patients were found to have undiagnosed metastases on explant pathology, with at least 22 unaccounted viable tumors before LT. Furthermore, 4 (57.1%) of the 7 patients who demonstrated complete radiographic response harbored viable carcinoma on explant pathology.

CONCLUSIONS

A complete radiographic response does not reliably predict a complete pathologic response. In patients with unresectable CRLM, total hepatectomy and LT represent a promising treatment options to prevent indolent disease progression from disappearing CRLM.

Synergistic Enzyme-Mimetic Catalysis-Based Non-Thermal Sonocavitation and Sonodynamic Therapy for Efficient Hypoxia Relief and Cancer Ablation

Non-invasive cancer treatment strategies that enable local non-thermal ablation, hypoxia relief, and reactive oxygen species (ROS) production to achieve transiently destroying tumor tissue and long-term killing tumor cells would greatly facilitate their clinical applications. However, continuously generating oxygen cavitation nuclei, reducing the transient cavitation sound intensity threshold, relieving hypoxia, and improving its controllability in the ablation area still remains a significant challenge. Here, in this work, an Mn-coordinated polyphthalocyanine sonocavitation agent (Mn-SCA) with large d-π-conjugated network and atomic Mn-N sites is identified for the non-thermal sonocavitation and sonodynamic therapy in the liver cancer ablation. In the tumor microenvironment, the catalytical generation of oxygen assists cavitation formation and generates microjets to ablate liver cancer tissue and relieve hypoxia, this work reports for the first time to utilize the enzymatic properties of Mn-SCA to lower the cavitation threshold in situ. Moreover, under pHIFU irradiation, high reactive oxygen species (ROS) production can be achieved. The two merits in liver cancer ablation are demonstrated by cell destruction and high tumor inhibition efficiency. This work will help deepen the understanding of cavitation ablation and the sonodynamic mechanisms related to the nanostructures and guide the design of sonocavitation agents with high ROS production for solid tumor ablation.

Effects of chronic liver disease on the outcomes of simultaneous resection of colorectal cancer with synchronous liver metastases: a propensity score matching study

Introduction

Given the rising prevalence of chronic liver disease (CLD), it is increasingly important to understand its impact on surgical outcomes. Our aim was to evaluate the impact of CLD on short-term outcomes in patients with colorectal cancer and synchronous liver metastases undergoing simultaneous surgery.

Methods

We retrospectively reviewed patients with colorectal cancer and liver metastases who underwent simultaneous resection between January 2013 and June 2022. Patients were divided into the CLD and non-CLD groups. Data regarding short-term surgical outcomes were compared between the two groups.

Results

A total of 187 patients were included. After propensity score matching, there were 42 patients in each group, and the basic characteristics of the two groups were similar. Patients with CLD had a significantly greater incidence of postoperative complications (47.6% vs. 26.2%; P = 0.042). The operation times of the CLD and non-CLD groups were similar (297 vs. 307.5 min, P = 0.537), and the blood loss was comparable between the two groups (250 vs. 155 ml, P = 0.066). No significant differences were observed between the two groups in pneumonia (P > 0.999), urinary infection rate (P > 0.999), ileus rate (P = 0.474), wound infection rates (P > 0.999), abdominal infection rate (P = 0.533), anastomotic leakage rate (P > 0.999), digestive hemorrhage rate (P > 0.999), bile leakage rate (P > 0.999), hepatic hemorrhage rate (P > 0.999), reoperation rate (P > 0.999), intensive care rate (P > 0.999), or severe liver failure (P > 0.999). There were no deaths in the two groups. CLD significantly prolonged the length of hospital stay (P = 0.011).

Discussion

CLD is an important factor affecting postoperative complications in patients with colorectal cancer liver metastases undergoing simultaneous surgery. Considering the large number of patients with CLD in China, more attention and medical care should be provided to patients with CLD who require simultaneous resection of colorectal cancer with synchronous liver metastases.

Liver Transplantation for Colorectal Liver Metastases: Is It Appropriate?

Colorectal cancer with liver metastases is a condition with significant morbidity and mortality that affects many people around the world. Many treatments exist to target liver metastases, including surgical resection, chemotherapy, nonsurgical liver-directed therapies, and liver transplantation. The field of transplant oncology is emerging as a promising alternative to palliative chemotherapy alone in appropriately selected patients. Though few clinical trials have been completed to evaluate safety of liver transplant for colorectal cancer metastases, there are several ongoing trials to hopefully make transplant a viable option for more patients with limited options.

PR, Bhoyar A, Desouza A, Saklani A, Goel M. Outcomes of Patients With Colorectal Liver Metastasis in the Developing World: Is Liver Transplantation for Unresectable Liver Metastasis, the Next Logical Step?

Background

While half of the patients with colorectal cancer develop metastasis, some 20% develop liver-only disease, and 10% of patients with unresectable liver disease live for 5 years. This study audits the outcomes of patients with colorectal liver metastasis to identify patients with unresectable liver metastasis eligible for a liver transplant.

Method

All patients with colorectal liver metastasis, irrespective of the presence of metastasis at other sites, registered between January 1, 2018, and December 31, 2019, were included in this retrospective audit. Patients in whom R0 Resection with adequate future liver remnant was not possible even after downstaging with chemotherapy were deemed unresectable. Overall survival was calculated using the Kaplan-Meier analysis. Patients eligible for a liver transplant were identified using the International Hepato-Pancreatico-Biliary Association (IHBPA) consensus guidelines and Oslo and Fong clinical risk scores.

Results

Out of 284 patients, 80 were treated with curative intent and 185 with palliative intent. At a median follow-up of 36 months, the median and 3-year OS were 37 months and 55% for the curative intent group and 9 months and 4% for the palliative intent group, respectively. Among 173 patients with liver-only metastasis, 13 patients (7%) satisfied the IHBPA consensus guidelines and had both Oslo and Fong scores of 2 or less. Transplant-eligible patients with unresectable liver metastasis had median and 3-year OS of 24 months and 25% against 9 months and 5% for ineligible patients, respectively.

Conclusion

Liver transplant has the potential to benefit a small but significant portion of patients with unresectable liver metastasis.

Long-Term Survival, Prognostic Factors, and Selection of Patients With Colorectal Cancer for Liver Transplant: A Nonrandomized Controlled Trial

Importance

Liver transplant for colorectal cancer with liver metastases was abandoned in the 1990s due to poor overall survival. From 2006, liver transplant for in nonresectable colorectal liver metastases has been reexamined through different prospective trials.

Objective

To determine predictive factors for transplant long-term survival and cure after liver transplant.

Design, Setting, and Participants

This was a prospective, nonrandomized controlled cohort study derived from different clinical trials on liver transplant for colorectal liver metastases from 2006 to 2020 at Oslo University Hospital. The trials differed in prognostic inclusion criteria, but the design was otherwise identical regarding follow-up scheme to determine disease recurrence, overall survival, and survival after relapse. Final data analysis was performed on December 31, 2021. All patients with colorectal liver metastases from comparable prospective liver transplant studies were included.

Exposure

Liver transplant.

Main outcomes and measures

Disease-free survival, overall survival, and survival time after recurrence were determined in all participants.

Results

A total of 61 patients (median [range] age, 57.8 [28.7-71.1] years; 35 male [57.4%]) underwent liver transplant at Oslo University Hospital. Posttransplant observation time ranged from 16 to 165 months, and no patient was lost to follow-up. Median disease-free period, overall survival, and survival after relapse were 11.8 (95% CI, 9.3-14.2) months, 60.3 (95% CI, 44.3-76.4) months, and 37.1 (95% CI, 4.6-69.5) months, respectively. Negative predictive factors for overall survival included the following: largest tumor size greater than 5.5 cm (median OS, 25.3 months; 95% CI, 15.8-34.8 months; P <.001), progressive disease while receiving chemotherapy (median OS, 39.8 months; 95% CI, 28.8-50.7 months; P = .02), plasma carcinoembryonic antigen values greater than 80 μg/L (median OS, 26.6 months; 95% CI, 22.7-30.6 months; P <.001), liver metabolic tumor volume on positron emission tomography of greater than 70 cm3 (26.6 months; 95% CI, 11.8-41.5 months; P <.001), primary tumor in the ascending colon (17.9 months; 95% CI, 0-37.5 months; P <.001), tumor burden score of 9 or higher (23.3 months; 95% CI, 19.2-27.4 months; P = .02), and 9 or more liver lesions (42.5 months; 95% CI, 17.2-67.8 months; P = .02). An Oslo score of 0 or Fong Clinical Risk Score of 1 yielded 10-year survival of 88.9% and 80.0%, respectively.

Conclusions and relevance

Results of this nonrandomized controlled trial suggest that selected patients with liver-only metastases and favorable pretransplant prognostic scoring had long-term survival comparable with conventional indications for liver transplant, thus providing a potential curative treatment option in patients otherwise offered only palliative care.

Surgical approach to achieve R0 resections in primary and metastatic liver tumors: a literature review

Background and Objective

Primary and metastatic liver tumors are a significant cause of mortality worldwide. Regardless of the etiology of the tumor, macro- and microscopically clear margins (R0) while preserving adequate function of the remaining organ are the main goals after liver resections. However, technically challenging procedures are required to achieve R0 resection. Currently, there is no consensus of which should be the ideal minimal safety margin for liver tumor resections, with contrasting reports in regards of safety, tumor recurrence and overall outcomes following R0. Therefore, we aim to review current worldwide surgical practices to achieve R0 resections for primary and metastatic liver tumors in challenging surgical techniques and their reported outcomes.

Methods

PubMed database, Google Scholar, and OVID Medline were searched for peer-reviewed original articles related to surgical techniques performed to achieve R0 resections in the setting of primary and/or metastatic liver tumors. An up-to-date review of English-language articles published between 2015 to July 2022 was performed.

Key Content and Findings

Primary and metastatic liver tumors can be effectively treated using hepatic resection. Current literature highlights that tumors involving major vascular structures are not uncommon. Surgical advances have allowed for vascular control techniques, as well as vascular resections to be performed in a feasible and safe manner to achieve R0 resections. Complex resections combining surgical techniques can be performed in certain population after a detailed evaluation. Liver transplantation (LT) have been used with varying degrees of success for treatment of patients with hepatocellular carcinoma, cholangiocarcinoma (CCA), colorectal liver metastases (CRLM), non-resectable CRLM and metastatic neuroendocrine tumors.

Conclusions

Safety and feasibility of R0 resections have been reported for multiple techniques. Technical complexity should not be a limitation to achieve or pursue R0 tumor resection. However, there has to be a balance between patient risk/benefit in attempting R0 resections. Adequate training of surgeons on implementation of complex techniques, as well as transplant oncology techniques applied to hepato-pancreato-biliary (HPB) surgery represents as a promising path to improve short and long-term outcomes for liver-related oncology patients.

Liver transplantation for unresectable colorectal liver metastasis

PURPOSE OF REVIEW

To summarize the current state of liver transplantation (LT) for unresectable colorectal liver metastases (uCRLM), and to address future directions.

RECENT FINDINGS

The Norwegian secondary cancer (SECA) I and SECA II studies demonstrated that after LT the 5-year survival of a highly selected group of patients with uCRLM could be as high as 60% and 83%, respectively. After long-term follow-up, the 5- and 10-year survival was shown to be 43% and 26%, respectively. Furthermore, data has accumulated in other countries and a North American study reported a 1.5-year survival of 100%. In addition, steady growth has been demonstrated in the US, with 46 patients transplanted to date and 19 centers enrolling patients for this indication. Lastly, although recurrence is almost universal in patients with a high tumor burden, it has not been an accurate surrogate for survival, reflecting the relatively indolent nature of recurrence after LT.

SUMMARY

Growing evidence has shown that excellent survival and even cure can be achieved in highly selected patients with uCRLM, with survival rates far superior than in patients treated with chemotherapy. The next step is to create national registries to standardize selection criteria and establish the optimal approach and best practices for incorporating LT for uCRLM into the treatment armamentarium.

Updates and Expert Opinions on Liver Transplantation for Gastrointestinal Malignancies

Transplant oncology is a relatively new field in which transplantation is used to treat patients who would otherwise be unresectable. New anticancer treatment paradigms using tumor and transplant immunology and cancer immunogenomics are emerging. In turn, liver transplantation (LT) has become a potential therapy for certain patients with colorectal cancer (CRC) with liver metastasis, hepatocellular (HCC), cholangiocarcinoma (CCA), and metastatic neuroendocrine tumor (NET) of the liver. Although there are established criteria for LT in HCC, evidence regarding LT as a treatment modality for certain gastrointestinal malignancies is still debated. The aim of this review is to highlight updates in the role of LT for certain malignancies, including HCC, metastatic CRC, hilar CCA, and neuroendocrine tumor (NET), as well as contextualize LT use and discuss controversies in transplant oncology.

Interventional radiological therapies in colorectal hepatic metastases

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

New Insights in the Setting of Transplant Oncology

Background and Objectives: Liver transplantation (LT) is the best strategy for curing several primary and secondary hepatic malignancies. In recent years, growing interest has been observed in the enlargement of the transplant oncology indications. This paper aims to review the most recent developments in the setting of LT oncology, with particular attention to LT for unresectable colorectal liver metastases (CRLM) and cholangiocellular carcinoma (CCA). Materials and Methods: A review of the recently published literature was conducted. Results: Growing evidence exists on the efficacy of LT in curing CRLM and peri-hilar and intrahepatic CCA in well-selected patients when integrating this strategy with (neo)-adjuvant chemotherapy, radiotherapy, or locoregional treatments. Conclusion: For unresectable CCA and CRLM management, several prospective protocols are forthcoming to elucidate LT’s impact relative to alternative therapies. Advances in diagnosis, treatment protocols, and donor-to-recipient matching are needed to better define the oncological indications for transplantation. Prospective, multicenter trials studying these advances and their impact on outcomes are still required.

Intentional R1 resection of liver metastases: A new treatment paradigm for patients with advanced colorectal cancer based on a propensity score-Matched case-control analysis

BACKGROUND

Clinical outcomes of colorectal cancer (CRC) patients after an incomplete microscopic (R1) resection of liver metastases may not differ from those following a microscopically margin negative (R0) resection, when the latest is not feasible because of anatomic issues. We aimed at comparing the clinical outcomes of CRC patients with an intentional R1 or with a R0 resection of liver metastases.

METHODS

All patients with advanced in CRC and liver metastases consecutively treated by liver resection between February 2005 and January 2019 at in the department of Digestive and Hepatobiliary Surgery of Henri Mondor University Hospital (Créteil, France) were included in this retrospective case-control study. Overall survival (OS) and event-free survival (EFS) were compared between patients who underwent an intentional (pre-operative decision) R1 resection (iR1) to those who had a R0 resection of liver metastases. To account for confounding, comparison between the 2 groups was performed after adjustment using propensity score analysis.

RESULTS

Twenty-six CRC patients treated by iR1 resection of liver metastases were compared to 98 patients treated by R0 resection. Median OS reached 39 months [95% confidence interval (CI): 25-67] and 63 months [95% CI: 52-76] in the iR1 and R0 groups, respectively. After adjustment by inverse probability of treatment weighting, patients' OS and EFS did not differ significantly between the iR1 and R0 groups (hazard ratio (HR): 1.19 [0.54-2.62] and 1.67 [0.93-3.03]), respectively.

CONCLUSION

iR1 resection of liver metastases in advanced CRC patients is an acceptable therapeutic strategy, when R0 resection is not feasible.

Liver Transplantation for Hepatic Metastases from Colorectal Cancer: Current Knowledge and Open Issues

More than 40% of patients with colorectal cancer present liver metastases (CRLM) during the course of their disease and up to 50% present with unresectable disease. Without surgical interventions, survival for patients treated with systemic therapies alone is dismal. In the past, liver transplantation (LT) for patients with unresectable CRLM failed to show any survival benefit due to poor selection, ineffective chemotherapeutic regimens, unbalanced immunosuppression and high perioperative mortality. Since then and for many years LT for CRLM was abandoned. The turning point occurred in 2013, when the results from the Secondary Cancer (SECA I) pilot study performed at Oslo University were published reporting a 60% 5-year overall survival after LT in patients with unresectable CRLM. These results effectively reignited the interest in LT as a potential therapy for CRLM, and several trials are undergoing. The aims of this article are to give a comprehensive overview of the available evidence on LT for CRLM, discuss the open issues in this rapidly evolving field, and highlight possible ways to address the future of this fascinating therapeutic alternative for selected patients with CRLM.

Colorectal Cancer Liver Metastases: Multimodal Therapy

Despite a steady decline in incidence and mortality rates, colorectal cancer (CRC) remains the second most common cancer diagnosis in women and the third most common in men worldwide. Notably, the liver is recognized as the most common site of CRC metastasis, and metastases to the liver remain the primary driver of disease-specific mortality for patients with CRC. Although hepatic resection is the backbone of curative-intent treatment, management of CRLM has become increasingly multimodal during the last decade and includes the use of downstaging chemotherapy, ablation techniques, and locoregional therapy, each of which are reviewed herein.

PET-Uptake in Liver Metastases as Method to Predict Tumor Biological Behavior in Patients Transplanted for Colorectal Liver Metastases Developing Lung Recurrence

The objective of the study was to determine the impact of PET uptake on liver metastases on overall survival (OS) after resection of pulmonary metastases in patients who had received liver transplantation (LT) due to unresectable colorectal liver-only metastases. Resection of pulmonary colorectal metastases is controversial. Some hospitals offer this treatment to selected patients, whereas other hospitals do not perform the procedure in colorectal cancer patients who develop pulmonary metastases. All patients included in the LT studies who developed pulmonary metastases as first site of relapse, and had resection of these as first treatment, were included in this report. Metabolic tumor volume (MTV) in liver was derived from the pre-transplant PET examinations. OS from time of resection was calculated by the Kaplan−Meier method. Patients with low MTV (<70 cm3) had significantly longer OS from time of resection of pulmonary metastases compared to patients with high MTV (>70 cm3). Patients with low MTV in the liver had 10-year OS from time of pulmonary resections of 86%. Liver MTV values from pre-transplant PET examinations may predict long OS in colorectal cancer patients with a resection of pulmonary metastases developing after LT. Thus, in selected colorectal cancer patients developing pulmonary metastases resection of these metastases should be the treatment of choice.

Tumors located in the central column of the liver are associated with increased surgical difficulty and postoperative complications following open liver resection for colorectal metastases

BACKGROUND

To assess the impact of difficult location (based on preoperative computed tomography) of liver metastases from colorectal cancer (LMCRC) on surgical difficulty, and occurrence of severe postoperative complications (POCs).

METHODS

A retrospective single-centre study of 911 consecutive patients with LMCRC who underwent hepatectomy by the open approach between 1998 and 2011, before implementation of laparoscopic surgery to obviate approach selection bias. LMCRC with at least one of the following four features on preoperative imaging: tumor invading the hepatocaval confluence or retro-hepatic inferior vena cava, centrally located (Segments 4,5,8) and >10 cm in diameter, abutting the supra-hilar area, or involving the paracaval portion or caudate process of Segment 1; were considered as topographically difficult (top-diff). Independent predictors of surgical difficulty assessed by number of blood units transfused, duration of ischemia, and number of sessions of pedicle clamping during surgery and of severe POCs were identified by multivariate analysis before, and after propensity score matching.

RESULTS

Top-diff tumor location independently predicted surgical difficulty. Severe POCs were associated with the tumor location [top-diff vs. topographically non difficult (non top-diff)], preoperative portal vein embolization, and variables related to surgical difficulty.

CONCLUSION

LMCRC in difficult location independently predicts surgical difficulty and severe POCs.

Liver transplantation in patients with post-hepatectomy liver failure - A Northern European multicenter cohort study

BACKGROUND

Liver transplantation (LTX) has been described as a rescue treatment option in severe, intractable post-hepatectomy liver failure (PHLF), but is not considered to be indicated for this condition by many hepatobiliary and transplant surgeons. In this article we describe the clinical experience of five northern European tertiary centers in using LTX to treat selected patients with severe PHLF.

METHODS

All patients subjected to LTX due to PHLF at the participating centers were identified from prospective clinical databases. Preoperative variables, surgical outcome (both resection surgery and LTX) and follow-up data were assessed.

RESULTS

A total of 10 patients treated with LTX due to severe PHLF from September 2008 to May 2020 were identified and included in the study. All patients but one were male and the median age was 70 years (range 49-72). In all patients the indication for liver resection was suspected malignancy, but in six patients post-resection pathology revealed benign or pre-malignant disease. There was no 90-day mortality after LTX. Patients were followed for a median of 49 months (13-153) and eight patients were alive without recurrence at last follow-up.

DISCUSSION

In selected patients with PHLF LTX can be a life-saving procedure with low short-term risk.

A contemporary systematic review on liver transplantation for unresectable liver metastases of colorectal cancer

The 5-year overall survival rate of a patient with unresectable metastatic colorectal cancer is poor at approximately 14%. Similarly, historical data on liver transplantation (LT) in those with colorectal liver metastases (CRLM) showed poor outcomes, with 5-year survival rates between 12% and 21%. More recently, limited data have shown improved outcomes in select patients with 5-year overall survival rates of approximately 60%. Despite these reported survival improvements, there is no significant improvement in disease-free survival. Given the uncertain benefit with this therapeutic approach and a renewed investigational interest, we aimed to conduct a contemporary systematic review on LT for CRLM. A systematic review of the literature was performed according to the preferred reporting items for systematic reviews and meta-analysis statement. English articles reporting on data regarding LT for CRLM were identified through the MEDLINE (via PubMed), Cochrane Library, and ClinicalTrials.gov databases (last search date: December 16th, 2021) by 2 researchers independently. A total of 58 studies (45 published and 13 ongoing) were included. Although early retrospective studies suggest the possibility that some carefully selected patients may benefit from LT, there is minimal prospective data on the topic and LT remains exploratory in the setting of CRLM. Additionally, several other challenges, such as the limited availability of deceased donor organs and defining appropriate selection criteria, remain when considering the implementation of LT for these patients. Further evidence from ongoing prospective trials is needed to determine if and to what extent there is a role for LT in patients with surgically unresectable CRLM.

Liver Transplantation as a Curative Approach for Patients With Nonresectable Colorectal Liver Metastases

OBJECTIVES

Liver transplant is emerging as a potential treatment option for patients with isolated colorectal liver metastasis. In this review article, we analyzed the published literature on liver transplant outcomes in such patients.

MATERIALS AND METHODS

Four prospective studies documenting the clinical outcomes in patients with colorectal liver metastasis who underwent liver transplant were analyzed to study the feasibility of liver transplant in such patients.

RESULTS

The SECA-II trial demonstrated the highest overall survival of 100%, 83%, and 83% at 1, 3, and 5 years, respectively, and disease-free survival of 53%, 44%, and 35%, respectively, with a narrow inclusion criterion. Conversely, extended criteria for selection and donors in arm D of the same trial resulted in median overall survival and disease-free survival of 18 and 4 months, respectively.

CONCLUSIONS

Liver transplant provided more prolonged overall survival compared with other therapeutic modalities. Patients with isolated colorectal liver metastasis of less aggressive biology, good performance status, at least 6 weeks of chemotherapy, low clinical risk scores, and negative nodal disease should be considered for patient selection. Moreover, exclusion criteria consisting of patients with the right-sided primary tumor, less than 3 years to liver transplant after diagnosis, and elevation of carbohydrate antigen (CA19-9) in the presence of BRAF mutation should be explored.

Current Surgical Management Strategies for Colorectal Cancer Liver Metastases

Simple Summary

Colorectal cancer is one of the most common cancer diagnoses in the world. At least half of patients diagnosed with colorectal cancer will develop metastatic disease, with most being identified in the liver. Surgical resection of colorectal liver metastases (CRLM) is potentially curative. Surgical resection of CRLM, however, remains underutilized despite the continued expansion of operative strategies available. This is likely due to differing views on resectability. Resectability is a surgical assessment, and the classification of CRLM as unresectable should only be made by an experienced hepatobiliary surgeon. Obtaining a surgical evaluation at the time of liver metastasis discovery may help mitigate the challenge of assessing resectability and the determination of potential operative time windows within current multimodal management strategies. The aim of this review is to help facilitate discussions surrounding resectability as well as the timing and sequencing of both surgical and non-surgical therapies.

Abstract

Colorectal cancer is the third most common cancer diagnosis in the world, and the second most common cause of cancer-related deaths. Despite significant progress in management strategies for colorectal cancer over the last several decades, metastatic disease remains difficult to treat and is often considered incurable. However, for patients with colorectal liver metastases (CRLM), surgical resection offers the best opportunity for survival, can be curative, and remains the gold standard. Unfortunately, surgical treatment options are underutilized. Misperceptions regarding resectable and unresectable CRLM likely play a role in this. The assessment of factors that impact resectability status like medical fitness, technical considerations, and disease biology can be difficult, necessitating careful multidisciplinary input and discussion. The identification of ideal operative time windows that align with the multimodal management of these patients can also be perplexing. For all patients with CRLM it may therefore be advantageous to obtain surgical evaluation at the time of discovering liver metastases to mitigate these challenges and minimize the risk of undertreatment. In this review we summarize current surgical management strategies for CRLM and discuss factors to be considered when determining resectability.

Role of liver transplantation in the management of colorectal liver metastases: Challenges and opportunities

The liver is the most common site of colorectal cancer metastasis. Complete resection of the metastatic tumor is currently the only treatment modality available with a potential for cure. However, only 20% of colorectal liver metastases (CRLM) are considered resectable at the time of presentation. Liver transplantation (LT) has been proposed as an alternative oncologic treatment for patients with unresectable CRLM. This review summarizes the published experiences of LT in the setting of unresectable CRLM from the previous decades and discusses the challenges and future horizons in the field. Contemporary experiences that come mostly from countries with broader access to liver grafts are also explored and their promising findings in terms of overall survival (OS) and disease-free survival (DFS) are outlined along with their study design and methods. The rationale of establishing specific patient selection criteria and the dilemmas around immunosuppressive regimens in patients undergoing LT for CRLM are also highlighted. Additionally, this review describes the findings of studies comparing LT vs chemotherapy alone and LT vs portal vein embolization plus resection for CRLM in terms of OS and DFS. Last but not least, we present current perspectives and ongoing prospective trials that try to elucidate the role of LT for CRLM.

Treatment of relapse and survival outcomes after liver transplantation in patients with colorectal liver metastases

Liver transplantation (LT) in selected colorectal cancer (CRC) patients with nonresectable liver-only metastases may result in 5-year overall survival of up to about 70-100%. However, the majority will have recurrent disease. All patients included in this report were included in prospective studies. Forty-four out of 56 patients had a relapse, and all 44 patients received treatment for recurrent disease. The organ of the first relapse was lung metastases in 23 of the 44 patients. The first treatment modality of the relapse was the treatment with curative intent in 55.8% of the patients, and chemotherapy was the first treatment administered to 25.6% of the patients. Patients receiving surgery of lung metastases had a 5-year overall survival of 66.5% from the time of metastasectomy. Patients receiving treatment with curative intent for metastases to other organs had a 5-year overall survival of 24.8%. Nine of the 44 patients had no evidence of disease (NED) at the end of the follow-up. Median time of NED in these patients was 54.3 months, and median overall survival from the time of LT was 8.4 years. Because of the high incidence of recurrent disease, these patients should have a systematic long-term follow-up since many of the relapses may be treated with curative intent.

Portal vein embolization: rationale, techniques, outcomes and novel strategies

The incidence of liver cancer has grown in the past decade, with 905,677 new cases and 830,180 deaths in 2020. According to the highest annual fatality ratio, liver cancer is the third-leading cause of cancer-related deaths worldwide. Surgical resection is the mainstay treatment for long-term survival. However, only 25% of patients are surgical candidates. Recent surgical concepts, techniques and multidisciplinary management were developed, including interventional radiology procedures that improve the management algorithm, expand the indications and limit dropouts from curative treatment. This review summarizes up-to-date information on interventional radiology in the management of liver tumors.

Liver Transplantation for Non-Resectable Liver Metastases from Colorectal Cancer: A Systematic Review and Meta-Analysis

BACKGROUNDS

Colorectal liver metastases were historically considered a contraindication to liver transplantation, but dismal outcomes for those with metastatic colorectal cancer and advancements in liver transplantation (LT) have led to a renewed interest in the topic. We aim to compare the current evidence for liver transplantation for non-resectable colorectal liver metastases (NRCLM) with the current standard treatment of palliative chemotherapy.

METHODS

A systematic review and meta-analysis of proportions was conducted following screening of MEDLINE, EMBASE, SCOPUS and CENTRAL for studies reporting liver transplantation for colorectal liver metastases. Post-operative outcomes measured included one-, three- and five-year survival, overall survival, disease-free survival and complication rate.

RESULTS

Three non-randomised studies met the inclusion criteria, reporting a total of 48 patients receiving LT for NRCLM. Survival at one-, three- and five-years was 83.3-100%, 58.3-80% and 50-80%, respectively, with no significant difference detected (p = 0.22, p = 0.48, p = 0.26). Disease-free survival was 35-56% with the most common site of recurrence being lung. Thirteen out of fourteen deaths were due to disease recurrence.

CONCLUSION

Although current evidence suggests a survival benefit conferred by LT in NRCLM compared to palliative chemotherapy, the ethical implications of organ availability and allocation demand rigorous justification. Concomitant improvements in the management of patients following liver resection and of palliative chemotherapy regimens is paramount.

Liver transplantation versus liver resection for colorectal liver metastasis: a survival benefit analysis in patients stratified according to tumor burden score

Liver transplantation (LT) for colorectal liver metastasis (CRLM) may provide excellent survival rates in patients with unresectable disease. High tumor load is a risk factor for recurrence and low overall survival (OS) after liver resection (LR). We tested the hypothesis that LT could offer better survival than LR in patients with high tumor load. LR performed at Padua University Hospital for CRLM was compared with LT for unresectable CRLM performed both at Oslo and Padua. High tumor load was defined as tumor burden score (TBS) ≥ 9, and inclusion criteria were as in the SECA-I transplant study. 184 patients were eligible: 128 LRs and 56 LTs. 5-year OS after LR and LT was 40.5% and 54.7% (P = 0.102). In the high TBS cohort, 5-year OS after LR and LT was 22.7% and 52.2% (P = 0.055). In patients with Oslo score ≤ 2 and TBS ≥ 9 (13 LR; 24 LT) the 5-year OS after LR and LT was 14.6% and 69.1% (P = 0.002). The corresponding disease-free survival (DFS) was 0% and 22.9% (P = 0.005). Selected CRLM patients with low Oslo score and high TBS could benefit from LT with survival outcomes that are far better than what is achieved by LR.

Liver transplantation in malignant disease

Liver transplantation for malignant disease has gained increasing attention as part of transplant oncology. Following the implementation of the Milan criteria, hepatocellular carcinoma (HCC) was the first generally accepted indication for transplantation in patients with cancer. Subsequently, more liberal criteria for HCC have been developed, and research on this topic is still ongoing. The evident success of liver transplantation for HCC has led to the attempt to extend its indication to other malignancies. Regarding perihilar cholangiocarcinoma, more and more evidence supports the use of liver transplantation, especially after neoadjuvant therapy. In addition, some data also show a benefit for selected patients with very early stage intrahepatic cholangiocarcinoma. Hepatic epithelioid hemangioendothelioma is a very rare but nonetheless established indication for liver transplantation in primary liver cancer. In contrast, patients with hepatic angiosarcoma are currently not considered to be optimal candidates. In secondary liver tumors, neuroendocrine cancer liver metastases are an accepted but comparability rare indication for liver transplantation. Recently, some evidence has been published supporting the use of liver transplantation even for colorectal liver metastases. This review summarizes the current evidence for liver transplantation for primary and secondary liver cancer.

Colon Rectal Liver Metastases: The Role of the Liver Transplantation in the Era of the Transplant Oncology and Precision Medicine

The development of liver metastases in colon rectal cancer has a strong impact on the overall survival (OS) of the patient, with a 5-year survival rate of 5% with palliative treatment. Surgical resection combined with pharmacological treatment can achieve a 5-year OS rate of 31-58%. However, in only 20% of patients with colon rectal liver metastases (CRLMs), liver resection is feasible. In highly selected patients, recent trials and studies proved that liver transplantation (LT) for non-resectable CRLM is a surgical option with an excellent long-term OS. The paper aims to review the indications and outcome of LT for CRLMs, with a special focus on immunosuppressive therapy and the management of local and extrahepatic recurrence after LT.