R1 Resection by Necessity for Colorectal Liver Metastases: Is It Still a Contraindication to Surgery?

A dosimetric comparison of different radiotherapy modalities for Non-Resected oligometastatic liver Disease

Purpose

The role of radiotherapy in the context of limited liver metastases is emerging rapidly with a variety of available technical approaches. Here, we provide a dosimetric comparison of three different radiotherapy modalities for non-resected liver metastases.

Methods

This multicentric study included 30 patients previously treated for solitary liver metastases. Interstitial high dose-rate brachytherapy (HDR), stereotactic body radiation therapy (SBRT), and kilovoltage electronic brachytherapy (eBT) with a single dwelling point, as an in this context novel modality, were planned with a 25-Gy single fraction and dosimetrically compared. The primary endpoint was difference in healthy liver tissue exposure. Secondary endpoints included target volume coverage, dose to the surrounding organs at risk (OARs), and radiation treatment time.

Results

The median (range) lesion volume was 9.3 (2.5 - 29.7) cm3. Electronic BT yielded a significantly better OAR dose sparing compared to SBRT. Radiation exposure to the healthy liver was significantly lower with eBT (V9.1 Gy 13.8 [3.4-41.6] cm3) and HDR (49.2 [12.7-116.8] cm3) when compared with SBRT (98.8 [54.3-303.7] cm3; p < 0.001 for both). Mean treatment time was shortest for SBRT (6.1 min vs. 7.8 min for HDR [p = 0.003] vs. 16.1 min for eBT [p < 0.001]). Equally, CTV D90% and D95% were superior for SBRT (p < 0.001 vs. HDR and eBT).

Conclusion

Minimally invasive single-catheter eBT provides a new potential approach in the context of unresectable liver metastases, with optimal OAR dose sparing, yet suboptimal target volume coverage. Combining the advantages of both modalities, a multi-dwelling eBT approach as in HDR might ease applicability in clinical routine with optimized target coverage while maintaining excellent OAR doses. Future prospective investigations are required to further define its role within well-established liver-directed therapies.

On-site recurrence risk after parenchymal R1 liver resection for colorectal metastases

BACKGROUND

Histologic microscopic positive resection margin is a debated prognostic factor in patients resected for colorectal liver metastases. This study aimed to assess whether patients with R1 resection experience recurrence at the site of the resection (on-site recurrence) and to identify predictive factors for recurrence profiles in patients with R1 margins after resection of colorectal liver metastases.

METHODS

All surgical colorectal liver metastasis resection cases with R1 parenchymal margin from September 2014 to March 2020 in our center were retrospectively included. Imaging was reviewed for each metastasis. All the analyses were performed per metastasis. Recurrence location was examined for each metastasis according to the site of the R1 margin and defined as on-site when recurrence was at the same place of the resected lesion. Prognostic factors for recurrence type were assessed using logistic regression.

RESULTS

Of 700 patients who underwent liver resection for colorectal liver metastases, 105 (15%) had at least 1 metastasis with R1 resection margin, representing 6.8% per metastasis. The median follow-up was 34 months. Overall recurrence occurred in 130 metastases (83.3%) with intrahepatic recurrence in 106 metastases (80.9%). On-site recurrence was observed for 49 metastases (31.4%) and isolated (without an additional recurrence site) for 20 metastases (12.8%). The on-site recurrence did not impact overall survival. Three predictive factors for on-site recurrence were found in the multivariate logistic regression: synchronous metastases, nonanatomic resection, and pathologic response tumor regression grade 4-5.

CONCLUSION

Intrahepatic localization of recurrence is more frequent than on-site recurrence after R1 parenchymal resection. Synchronous metastases, nonanatomic resection, and tumor regression grade 4-5 may impact the risk of on-site recurrence.

Efficacy of laparoscopic parenchyma-sparing hepatectomy using augmented reality navigation combined with fluorescence imaging for colorectal liver metastases: a retrospective cohort study using inverse probability treatment weighting analysis

BACKGROUND

Laparoscopic parenchyma-sparing hepatectomy (PSH) is an effective treatment for colorectal liver metastases (CRLMs), but ensuring the safety and radicality of the procedure, particularly for deep-seated tumors, remains challenging. Surgical navigation technologies such as augmented reality navigation (ARN) and indocyanine green fluorescence imaging (ICG-FI) are increasingly utilized to guide surgery, yet their efficacy for CRLMs is unclear. This study aims to evaluate the short-term and long-term outcomes of ARN combined with ICG-FI-guided (ARN-FI) laparoscopic PSH for CRLMs.

METHODS

Between January 2020 and December 2022, 89 consecutive patients who underwent laparoscopic PSH for CRLMs were included in the study. Patients were divided into an ARN-FI group ( n = 38) and a non-ARN-FI group ( n = 51) based on the use of ARN-FI. Inverse probability treatment weighting (IPTW) was used to balance baseline characteristics and minimize potential selection bias. Short-term and long-term outcomes were compared between the two groups. Cox regression analysis was conducted to identify risk factors associated with recurrence-free survival (RFS) and hepatic RFS.

RESULTS

After IPTW, there were 87 patients in the ARN-FI group and 89 patients in the non-ARN-FI group. Shorter parenchymal transection time, postoperative hospital stays, and wider margins were observed in the ARN-FI group. There was no significant difference in RFS or hepatic RFS between the groups. Mutant KRAS status was an independent risk factor for both RFS and hepatic RFS, while tumor diameter ≥ 5 cm and deep-seated location were risk factors for hepatic RFS. In the subgroup analysis of deep-seated tumors, the ARN-FI group also showed less intraoperative blood loss, a lower rate of strategy change, shorter postoperative recovery times, a higher R0 resection rate, and improved RFS and hepatic RFS.

CONCLUSIONS

In laparoscopic PSH for CRLMs, ARN-FI may improve surgical efficiency and accuracy. Especially for deep-seated tumors, it has the potential to reduce blood loss and attain higher R0 resection rates.

The Current State of Perioperative Chemotherapy in Resectable Colorectal Liver Metastases: A Narrative Review

Perioperative chemotherapy has emerged as a critical component in managing resectable colorectal liver metastases (CRLM), aiming to improve long-term survival, although data supporting its use remains controversial. This narrative review explores the current state of perioperative chemotherapy in patients with resectable CRLM, focusing on its role in different oncological risk categories. The review highlights ongoing controversies, such as optimal patient selection and the role of post- versus preoperative treatment in specific scenarios.

Orosomucoid 2 upregulation mediates liver injury-induced colorectal cancer liver metastasis by promoting EMT and cell migration

The relationship between drug-induced liver injury and liver metastasis of colorectal cancer and the underlying mechanisms are not well understood. In this study, we used carbon tetrachloride to construct a classic mouse liver injury model and injected CT26 colorectal cancer cells into the mouse spleen to simulate the natural route of colorectal cancer liver metastasis. Liver injury significantly increased the number of colorectal cancer liver metastases. Transcriptome sequencing and data-independent acquisition protein quantification identified proteins that were significantly differentially expressed in injured livers, and orosomucoid (ORM) 2 was identified as a target protein for tumor liver metastasis. In vitro experiments showed that exogenous ORM2 protein increased the expression of EMT markers such as Twist, Zeb1, Vim, Snail1 and Snail2 and chemokine ligands to promote CT26 cell migration. In addition, liver-specific overexpression of the ORM2 protein in the mouse model significantly promoted tumor cell liver metastasis without inducing liver injury. Our results indicate that drug-induced liver injury can promote colorectal cancer liver metastasis and that ORM2 can promote cell migration by inducing EMT in tumor cells.

Comprehensive data of 5085 patients newly diagnosed with colorectal liver metastasis between 2013 and 2017: Fourth report of a nationwide survey in Japan

The Joint Committee for Nationwide Survey on colorectal liver metastasis (CRLM) was established to improve treatment outcomes in patients with CRLM. The aim of this study was to evaluate the transition in the characteristics and treatment strategies of patients with CRLM and to analyze the prognostic factors. The data of 5085 patients newly diagnosed between 2013 and 2017 were compared with those of 3820 patients from 2005 and 2007. In patients who underwent hepatectomy (n = 2759 and 2163), the number of CRLMs was significantly higher and in the 2013-2017 data than in the 2005-2007 data (median 2 vs. 1; p = .005). Overall survival (OS) rates after diagnosis of CRLM after hepatectomy were better in the 2013-2017 data than that in the 2005-2007 data (5-year OS, 62.4% vs. 56.7%, p < .001). Recurrence-free survival (RFS) after hepatectomy was comparable between the groups (5-year RFS, 30.5% vs. 30.7%; p = .068). Multivariate analyses identified age at diagnosis of CRLM ≥70 years, lymph node metastasis of primary lesion, preoperative carbohydrate antigen (CA) 19-9 value >100 U/mL, number of CRLM 2-4, and R2 resection as independent predictors of OS. Synchronous CRLM, concomitant extrahepatic metastasis, lymphatic invasion, lymph node metastasis of primary lesion, preoperative CA19-9 value >100 U/mL, number of CRLM 5-, and nonlaparoscopic approach were selected as that of RFS. Despite having a higher prevalence of advanced stage CRLM in the 2013-2017 patient population compared to the 2005-2007 cohort, prognostic outcomes demonstrably improved in the later period.

Optimal treatment strategies for borderline resectable liver metastases from colorectal cancer

BACKGROUND

Traditionally, colorectal liver metastases (CRLMs) are divided into "initially resectable" and "initially unresectable." The terminology "borderline resectable" continues to be elusive without any common consensus or definition. This narrative review aims to decode the conundrum of "borderline resectable CRLM (BR-CRLM)" and to discuss optimal treatment strategies.

METHODS

A comprehensive review was performed using Medline/PubMed and Web of Science databases with a search period ending on January 1, 2024. Using PubMed, the terms "CRLM," "BR-CRLM," and "management of BR-CRLM" were searched.

RESULTS

The 2016 European Society for Medical Oncology guidelines defined the term "resectability" in CRLM using the "technical (surgical) criteria" and the "oncologically criteria." These 2 criteria form the basis of defining BR-CRLM. Thus, BR-CRLM can be either technically easy but with unfavorable oncologically criteria or technically difficult with favorable oncologically criteria. Although defining BR-CRLM by incorporating both these criteria seems to be the most logical way forward, there is currently a lot of heterogeneity in the literature. It is generally agreed upon that some form of chemotherapy needs to be administered in BR-CRLM before embarking on surgery. Conversion chemotherapy is used in patients with BR-CRLM in which there is a possibility of resection after effective downsizing. Along with improved effective chemotherapy, great strides have been made in pushing the limits of surgery to achieve resectability in this subset of patients.

CONCLUSION

Advanced surgical techniques and locoregional liver-directed therapies coupled with perioperative chemotherapy with or without targeted therapy have made long-term survival benefit, a reality in patients with BR-CRLM. Thus, the time has come to recognize "BR-CRLM" as a distinct entity.

The Effect of Hepatic Surgical Margins of Colorectal Liver Metastases on Prognosis: A Systematic Review and Meta-Analysis

Introduction: Colorectal cancer is the third most common malignancy, with around half of patients developing liver metastases. Hepatectomy is the preferred treatment, but its success depends on several factors, including surgical margins. Various surgical margins have been suggested to achieve optimal results. This systematic review and meta-analysis aim to explore the impact of negative surgical margins ranging from 1 to 10 mm, and >10 mm on survival, with the objective of identifying optimal surgical margins. Methods: A systematic literature search was conducted on the MEDLINE, Scopus, and Cochrane databases. The six included studies that examined the effect of surgical margins at the aforementioned distances on patient survival. Studies were assessed for risk of bias using the Quality in Prognosis Studies tool. Statistical analysis was performed using SPSS software. Results: The results of the meta-analysis revealed the superiority of wider surgical margins (>10) on overall survival compared to smaller margins (1-10 mm), as the HR was calculated to be 1.38 [1.10; 1.73]. Specifically, negative margins between 1 and 10 mm are linked to a 38% increased risk of mortality compared to margins larger than 10 mm. The low heterogeneity indicates consistent findings across studies, and the statistically significant hazard ratio underscores the importance of aiming for larger surgical margins to enhance patient outcomes. In the subgroup that included only studies in which patients received neoadjuvant therapy, the HR was 1.48 [1.06; 2.07], further emphasizing the importance of ensuring negative surgical margins in today's era. Conclusions: In summary, this systematic review and meta-analysis highlights the impact of surgical margin width on the survival of patients with colorectal liver metastases, as well as the importance of margin optimization in surgical management strategies.

Resection of colorectal liver metastases with second-line aflibercept plus FOLFIRI: Results from the RESECTION prospective French cohort

AIM

To evaluate R0/R1 resection rate in patients with colorectal liver metastases (CLM) treated with aflibercept plus FOLFIRI after failure of a prior oxaliplatin-based regimen in daily clinical practice.

METHODS

This French, multicentre, prospective, observational cohort (NCT05178745) included patients with CLM (alone or predominant; up to 5 lung nodules <2 cm allowed) initiating aflibercept plus FOLFIRI every 2 weeks per physician choice. Primary endpoint was R0/R1 resection rate. Secondary endpoints included overall survival (OS), progression-free survival (PFS), radiological and pathological responses, and safety.

RESULTS

A total of 137 patients (median age 65 years, RAS/BRAF mutant 57 %/9 %) were enrolled at 22 French sites. CLM (median 4) were synchronous in 82 %, bilobar in 71 % and located in liver only in 54 %. Overall, 17 % of patients had R0/R1 resection (21 % for patients with liver-only disease). A major pathological response per Blazer score was observed in 55 % of resected patients, along with significantly longer OS (median 34.8 vs 9.1 months, p < 0.0001) and PFS (median 11.4 vs 4.9 months, p < 0.0001) compared to non-resected patients. Post-operative complications occurred in 17 % of patients (all Dindo-Clavien grade I-II) and there was no post-operative deaths. Overall, 34 % had grade ≥ 3 adverse events, mainly general health deterioration and diarrhea.

CONCLUSIONS

Results suggest that aflibercept plus FOLFIRI, after failure of a prior oxaliplatin-based regimen, allows R0/R1 resection of CLM in almost 20 % of patients with a major pathological response in most cases and a median OS prolonged by more than 3-fold versus non-resected patients.

Prognostic implications of margin status in association with systemic treatment in a cohort study of patients with resection of colorectal liver metastases

BACKGROUND

This study investigates the impact of margin status after colorectal liver metastasis (CLM) resection on outcomes of patients after neoadjuvant treatment versus those who underwent upfront resection.

METHODS

An international collaborative database of CLM patients who underwent surgical resection was used. Proportional hazard regression models were created for single and multivariable models to assess the relationship between independent measures and median overall survival (mOS).

RESULTS

R1 was associated with worse OS in the neoadjuvant group (mOS: 51.8 m for R0 vs. 26.0 m for R1; HR: 2.18). In the patients who underwent upfront surgery, R1 was not associated with OS. (mOS: 46.7 m for R0 vs. 42.6 m for R1). When patients with R1 in each group were stratified by adjuvant treatment, there was no significant difference in the neoadjuvant group, while in the upfront surgery group with R1, adjuvant treatment was associated with significant improvement in OS (mOS: 42.6 m for adjuvant vs. 25.0 m for no adjuvant treatment; HR: 0.21).

CONCLUSION

R1 is associated with worse outcomes in the patients who receive neoadjuvant treatment with no significant improvement with the addition of adjuvant therapy, likely representing an aggressive tumor biology. R1 did not impact OS in patients with upfront surgery who received postoperative chemotherapy.

New trends in surgery for colorectal liver metastasis

By presenting the most up-to-date findings and incorporating the latest evidence, this article seeks to present a comprehensive guide for navigating the complexities inherent in the management of colorectal liver metastasis. It aims to serve as a valuable resource offering clinicians and healthcare professionals an understanding of the diverse modalities and approaches available for treating this challenging and multifaceted disease. In an era of rapidly evolving medical knowledge, this article examines the latest insights to make informed decisions in the realm of colorectal liver metastasis management. The article does not only highlight the up-to-date knowledge but also provides the evidence for existing therapeutic strategies. This practical tool provides evidence-based recommendations to clinicians, thereby contributing to the ongoing advancement of effective treatment strategies for this challenging disease.

Challenges and Opportunities for Precision Surgery for Colorectal Liver Metastases

The incidence of colorectal cancer and colorectal liver metastases (CRLM) is increasing globally due to an interaction of environmental and genetic factors. A minority of patients with CRLM have surgically resectable disease, but for those who have resection as part of multimodal therapy for their disease, long-term survival has been shown. Precision surgery-the idea of careful patient selection and targeting of surgical intervention, such that treatments shown to be proven to benefit on a population level are the optimal treatment for each individual patient-is the new paradigm of care. Key to this is the understanding of tumour molecular biology and clinically relevant mutations, such as KRAS, BRAF, and microsatellite instability (MSI), which can predict poorer overall outcomes and a poorer response to systemic therapy. The emergence of immunotherapy and hepatic artery infusion (HAI) pumps show potential to convert previously unresectable disease to resectable disease, in addition to established systemic and locoregional therapies, but the surgeon must be wary of poor-quality livers and the spectre of post-hepatectomy liver failure (PHLF). Volume modulation, a cornerstone of hepatic surgery for a generation, has been given a shot in the arm with the advent of liver venous depletion (LVD) ensuring significantly more hypertrophy of the future liver remnant (FLR). The optimal timing of liver resection for those patients with synchronous disease is yet to be truly established, but evidence would suggest that those patients requiring complex colorectal surgery and major liver resection are best served with a staged approach. In the operating room, parenchyma-preserving minimally invasive surgery (MIS) can dramatically reduce the surgical insult to the patient and lead to better perioperative outcomes, with quicker return to function.

Safety and feasibility of chemotherapy followed by liver transplantation for patients with definitely unresectable colorectal liver metastases: insights from the TransMet randomised clinical trial

BACKGROUND

Despite the increasing efficacy of chemotherapy (C), the 5-year survival rate for patients with unresectable colorectal liver metastases (CLM) remains around 10%. Liver transplantation (LT) might offer a curative approach for patients with liver-only disease, yet its superior efficacy compared to C alone remains to be demonstrated.

METHODS

The TransMet randomised multicentre clinical trial (NCT02597348) compares the curative potential of C followed by LT versus C alone in patients with unresectable CLM despite stable or responding disease on C. Patient eligibility criteria proposed by local tumour boards had to be validated by an independent committee via monthly videoconferences. Outcomes reported here are from a non-specified interim analysis. These include the eligibility of patients to be transplanted for non resectable colorectal liver metastases, as well as the feasibility and the safety of liver transplantation in this indication.

FINDINGS

From February 2016 to July 2021, 94 (60%) of 157 patients from 20 centres in 3 countries submitted to the validation committee, were randomised. Reasons for ineligibility were mainly tumour progression in 50 (32%) or potential resectability in 13 (8%). The median delay to LT after randomisation was 51 (IQR 30-65) days. Nine of 47 patients (19%, 95% CI: 9-33) allocated to the LT arm failed to undergo transplantation because of intercurrent disease progression. Three of the 38 transplanted patients (8%) were re-transplanted, one of whom (3%) died post-operatively from multi-organ failure.

INTERPRETATION

The selection process of potential candidates for curative intent LT for unresectable CLM in the TransMet trial highlighted the critical role of an independent multidisciplinary validation committee. After stringent selection, the feasibility of LT was 81%, as 19% had disease progression while on the waiting list. These patients should be given high priority for organ allocation to avoid dropout from the transplant strategy.

FUNDING

No source of support or funding from any author to disclose for this work. The trial was supported by the Assistance Publique - Hôpitaux de Paris (AP-HP).

Importance of resection margin after resection of colorectal liver metastases in the era of modern chemotherapy: population-based cohort study

BACKGROUND

Resection margin has been associated with overall survival following liver resection for colorectal liver metastasis. The aim of this study was to examine how resection margins of 0.0 mm, 0.1-0.9 mm and ≥1 mm influence overall survival in patients resected for colorectal liver metastasis in a time of modern perioperative chemotherapy and surgery.

METHODS

Using data from the national registries Swedish Colorectal Cancer Registry and Swedish National Quality Registry for Liver, Bile Duct and Gallbladder Cancer, patients that had liver resections for colorectal liver metastasis between 2009 and 2013 were included. In patients with a narrow or unknown surgical margin the original pathological reports were re-reviewed. Factors influencing overall survival were analysed using a Cox proportional hazard model.

RESULTS

A total of 754 patients had a known margin status, of which 133 (17.6%) patients had a resection margin <1 mm. The overall survival in patients with a margin of 0 mm or 0.1-0.9 mm was 42 (95% c.i. 31 to 53) and 48 (95% c.i. 35 to 62) months respectively, compared with 75 (95% c.i. 65 to 85) for patients with ≥1 mm margin, P < 0.001. Margins of 0 mm or 0.1-0.9 mm were associated with poor overall survival in the multivariable analysis, HR 1.413 (95% c.i. 1.030 to 1.939), P = 0.032, and 1.399 (95% c.i. 1.025 to 1.910), P = 0.034, respectively.

CONCLUSIONS

Despite modern chemotherapy the resection margin is still an important factor for the survival of patients resected for colorectal liver metastasis, and a margin of ≥1 mm is needed to achieve the best possible outcome.

The association between KRAS and histopathological growth patterns and the impact on resection margins around vasculature and bile ducts in colorectal liver metastases

The liver is the most frequent and often the only site of distant disease in colorectal cancer and, of all treatment protocols currently in use, resection is the most likely to result in long-term cure. Within the liver, tumour proximity to major vasculature and biliary structures poses a resection challenge, requiring a balance of achieving negative margins while preserving adequate vascular circulation and biliary drainage. The focus on parenchymal sparing resections are important but just as important may be the 'biological' behaviour of the tumour. In colorectal liver metastases (CRLM), biomarkers such as the Kirsten rat sarcoma oncogene homologue (KRAS) gene and histological growth patterns (HGPs) further improve the prognostication after resection. However, to date, the association between the KRAS status and HGPs in CRLM and their impact on resection margins around major vasculature or biliary structures in terms of overall survival and recurrence rates are unclear. The aim of this review was to explore the available evidence for the association between KRAS and HGPs in CRLM and attempt to define their impact on resection margins near major structures.

The significance of resection margins on R0 results in intrahepatic cholangiocarcinoma

BACKGROUND

Intrahepatic cholangiocarcinoma is the second most common primary liver cancer after hepatocellular carcinoma with an increasing incidence worldwide. Surgical resection is still the only potential cure, and survival rates are dismal due to disease relapse after resection and/or metastatic disease. Positive resection margins are associated with recurrence, with conflicting studies regarding the benefits of wide resection margins to reduce recurrence rates.

METHODS

126 patients with an R0 resection treated with hepatic surgery for intrahepatic cholangiocarcinoma at the Surgical Department at the Medical University Centre Essen, Germany were identified in a database and retrospectively analysed. Patients were grouped into three groups according to margin width, <1 mm (very narrow margin width) 1-5 mm (narrow margin width) and >5 mm (wide margin width). Epidemiological as well as perioperative data was analysed, and a univariate analysis as well as Kaplan-Meier plots carried out to investigate recurrence-free and overall survival.

RESULTS

Wider resection margins did not lead to better recurrence-free survival. A wider resection margin >5 mm was not significantly associated with improved overall survival. Positive lymph nodes (HR 2.50, 95% CI 1.11-5.61, p=0.027) and non-anatomic resections (HR 2.06, 95% CI 1.13-3.75, p=0.019) are significantly associated with poorer overall survival. Regarding recurrence-free survival, V2 vascular invasion was the only risk factor statistically significantly associated with poorer recurrence-free survival (HR 8.83, 95% CI 0.85-2.83, p=0.005).

CONCLUSION

Resection margins did not have a significant impact on disease free survival or overall survival following hepatic resection for intrahepatic cholangiocarcinoma. Non-anatomical resections, lymph node and vascular invasion all significantly impacted oncological outcomes.

Is Precision Surgery Applicable to Colorectal Liver Metastases? A Systematic Review and Meta-analysis of Studies that Investigate the Association of Surgical Technique with Outcomes in the Context of Distinct Tumor Biology

BACKGROUND

Although some data suggest that patients with mutRAS colorectal liver metastases (CRLM) may benefit from anatomic hepatectomy, this topic remains controversial. We performed a systematic review and meta-analysis to determine whether RAS mutation status was associated with prognosis relative to surgical technique [anatomic resection (AR) vs. nonanatomic resection (NAR)] among patients with CRLM.

PATIENTS AND METHODS

A systematic review and meta-analysis of studies were performed to investigate the association of AR versus NAR with overall and liver-specific disease-free survival (DFS and liver-specific DFS, respectively) in the context of RAS mutation status.

RESULTS

Overall, 2018 patients (831 mutRAS vs. 1187 wtRAS) were included from five eligible studies. AR was associated with a 40% improvement in liver-specific DFS [hazard ratio (HR) = 0.6, 95% confidence interval (CI) 0.44-0.81, p = 0.01] and a 28% improvement in overall DFS (HR = 0.72, 95% CI 0.54-0.95, p = 0.02) among patients with mutRAS tumors; in contrast, AR was not associated with any improvement in liver-specific DFS or overall DFS among wtRAS patients. These differences may have been mediated by the 40% decreased incidence in R1 resection among patients with mutRAS tumors who underwent AR versus NAR [relative risk (RR): 0.6, 95% CI 0.40-0.91, p = 0.02]. In contrast, the probability of an R1 resection was not decreased among wtRAS patients who underwent AR versus NAR (RR: 0.93, 95% CI 0.69-1.25, p = 0.62).

CONCLUSIONS

The data suggest that precision surgery may be relevant to CRLM. Specifically, rather than a parenchymal sparing dogma for all patients, AR may have a role in individuals with mutRAS tumors.

Contemporary Surgical Management of Colorectal Liver Metastases

Colorectal cancer is the third most common cancer in the United States and the second most common cause of cancer-related death. Approximately 20-30% of patients will develop hepatic metastasis in the form of synchronous or metachronous disease. The treatment of colorectal liver metastasis (CRLM) has evolved into a multidisciplinary approach, with chemotherapy and a variety of locoregional treatments, such as ablation and portal vein embolization, playing a crucial role. However, resection remains a core tenet of management, serving as the gold standard for a curative-intent therapy. As such, the input of a dedicated hepatobiliary surgeon is paramount for appropriate patient selection and choice of surgical approach, as significant advances in the field have made management decisions extremely nuanced and complex. We herein aim to review the contemporary surgical management of colorectal liver metastasis with respect to both perioperative and operative considerations.

Relationship between hepatic surgical margins of colorectal cancer liver metastases and prognosis: A review

Colorectal cancer (CRC) remains a significant global health concern, as characterized by its high mortality rate ranking second among all the leading causes of death. The liver serves as the primary site of CRC metastasis, and the occurrence of liver metastasis is a significant contributor to mortality among patients diagnosed with CRC. The survival rate of patients with colorectal liver metastasis has significantly increased with the advancement of comprehensive tumor therapy. However, radical surgery remains the key factor. Since there are frequently multiple liver metastases, which are prone to recurrence after surgery, it is crucial to preserve as much liver parenchyma as possible without affecting the prognosis. The issue of surgical margins plays a crucial role in this regard. In this review, we begin by examining the occurrence of positive surgical margins in liver metastases of patients diagnosed with CRC. We aim to define positive margins in hepatic surgery, examine the relationship between margins and prognosis and establish a foundation for future research in this field.

[Videofluorescence navigation during parenchymal-sparing liver resections using a domestic fluorescence imaging system]

Parenchyma- sparing liver resections are aimed at maximizing the possible preservation of parenchyma not affected by the tumor - a current trend in hepatopancreatobiliary surgery. On the other hand, a prerequisite for operations is to ensure their radicality. To effectively solve this problem, all diagnostic imaging methods available in the arsenal are used, which make it possible to comprehensively solve the issues of perioperative planning of the volume and technical features of the planned operation. Diagnostic imaging methods that allow intraoperative navigation through intraoperative, instrumentally based determination of the tumor border and resection plane have additional value. One of the methods of such mapping is ICG video fluorescence intraoperative navigation. An analysis of the clinical use of the domestic video fluorescent navigation system "MARS" for parenchymal-sparing resections of focal liver lesions is presented. An assessment was made of the dynamics of the distribution of the contrast agent during ICG videofluorescent mapping during parenchymal-sparing resection interventions on the liver, with the analysis of materials from histological examination of tissues taking into account three-zonal videofluorescent marking of the resection edge, performed using the domestic videofluorescence imaging system «MARS».

The Use of Hepatic Artery Infusion Chemotherapy for Unresectable Colorectal Cancer Liver Metastases

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in men and women (Siegel et al. in CA Cancer J Clin 72(1):7-33). Over one-half of newly diagnosed individuals will develop liver metastases. Among those with liver-only metastatic disease, only about one in five will be candidates for potentially curable resection.

Tata Memorial Centre Evidence Based Management of Colorectal cancer

This review article examines the evidence-based management of colorectal cancers, focusing on topics characterized by ongoing debates and evolving evidence. To contribute to the scientific discourse, we intentionally exclude subjects with established guidelines, concentrating instead on areas where the current understanding is dynamic. Our analysis encompasses a thorough exploration of critical themes, including the evidence surrounding complete mesocolic excision and D3 lymphadenectomy in colon cancers. Additionally, we delve into the evolving landscape of perioperative chemotherapy in both colon and rectal cancers, considering its nuanced role in the context of contemporary treatment strategies. Advancements in surgical techniques are a pivotal aspect of our discussion, with an emphasis on the utilization of minimally invasive approaches such as laparoscopy and robotic surgery in both colon and rectal cancers, including advanced rectal cases. Moving beyond conventional radical procedures, we scrutinize the feasibility and implications of endoscopic resections for small tumors, explore the paradigm of organ preservation in locally advanced rectal cancers, and assess the utility of total neoadjuvant therapy in the current treatment landscape. Our final segment reviews pivotal trials that have significantly influenced the management of colorectal liver and peritoneal metastasis.

Vessel-Guided Mesohepatectomy for Liver Partition and Staged Major Parenchyma-Sparing Hepatectomies with Super-Selective Portal Vein Embolization or Enhanced ALPPS to Achieve R0 Resection for Colorectal Liver Metastases at the Hepatocaval Confluence

Background. R0 minor parenchyma-sparing hepatectomy (PSH) is feasible for colorectal liver metastases (CRLM) in contact with hepatic veins (HV) at hepatocaval confluence since HV can be reconstructed, but in the case of contact with the first-order glissonean pedicle (GP), major hepatectomy is mandatory. To pursue an R0 parenchyma-sparing policy, we proposed vessel-guided mesohepatectomy for liver partition (MLP) and eventually combination with liver augmentation techniques for staged major PSH. Methods. We analyzed 15 consecutive vessel-guided MLPs for CRLM at the hepatocaval confluence. Patients had a median of 11 (range: 0-67) lesions with a median diameter of 3.5 cm (range: 0.0-8.0), bilateral in 73% of cases. Results. Grade IIIb or more complications occurred in 13%, median hospital stay was 14 (range: 6-62) days, 90-day mortality was 0%. After a median follow-up of 17.5 months, 1-year OS and RFS were 92% and 62%. In nine (64%) patients, MLP was combined with portal vein embolization (PVE) or ALPPS to perform staged R0 major PSH. Future liver remnant (FLR) volume increased from a median of 15% (range: 7-20%) up to 41% (range: 37-69%). Super-selective PVE was performed in three (33%) patients and enhanced ALPPS (e-ALPPS) in six (66%). In two e-ALPPS an intermediate stage of deportalized liver PSH was necessary to achieve adequate FLR volume. Conclusions. Vessel-guided MLP may transform the liver in a paired organ. In selected cases of multiple bilobar CRLM, to guarantee oncological radicality (R0), major PSH is feasible combining advanced surgical parenchyma sparing with liver augmentation techniques when FLR volume is insufficient.

Development and validation of a novel risk score to predict overall survival following surgical clearance of bilobar colorectal liver metastases

BACKGROUND

Bilobar liver metastases from colorectal cancer pose a challenge for obtaining a satisfactory oncological outcome with an adequate future liver remnant. This study aimed to assess the clinical and pathological determinants of overall survival and recurrence-free survival among patients undergoing surgical clearance of bilobar liver metastases from colorectal cancer.

METHODS

A retrospective international multicentre study of patients who underwent surgery for bilobar liver metastases from colorectal cancer between January 2012 and December 2018 was conducted. Overall survival and recurrence-free survival at 1, 2, 3 and 5 years after surgery were the primary outcomes evaluated. The secondary outcomes were duration of postoperative hospital stay, and 90-day major morbidity and mortality rates. A prognostic nomogram was developed using covariates selected from a Cox proportional hazards regression model, and internally validated using a 3:1 random partition into derivation and validation cohorts.

RESULTS

A total of 1236 patients were included from 70 centres. The majority (88 per cent) of the patients had synchronous liver metastases. Overall survival at 1, 2, 3 and 5 years was 86.4 per cent, 67.5 per cent, 52.6 per cent and 33.8 per cent, and the recurrence-free survival rates were 48.7 per cent, 26.6 per cent, 19.2 per cent and 10.5 per cent respectively. A total of 25 per cent of patients had recurrent disease within 6 months. Margin positivity and progressive disease at liver resection were poor prognostic factors, while adjuvant chemotherapy in margin-positive resections improved overall survival. The bilobar liver metastases from colorectal cancer-overall survival nomogram was developed from the derivation cohort based on pre- and postoperative factors. The nomogram's ability to forecast overall survival at 1, 2, 3 and 5 years was subsequently validated on the validation cohort and showed high accuracy (overall C-index = 0.742).

CONCLUSION

Despite the high recurrence rates, overall survival of patients undergoing surgical resection for bilobar liver metastases from colorectal cancer is encouraging. The novel bilobar liver metastases from colorectal cancer-overall survival nomogram helps in counselling and informed decision-making of patients planned for treatment of bilobar liver metastases from colorectal cancer.

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.

Survival outcomes for patients with colorectal cancer with synchronous liver only metastasis

BACKGROUND

Colorectal cancer with synchronous liver-only metastasis is managed with a multimodal approach, however, optimal sequencing of modalities remains unclear.

METHODS

A retrospective review of all consecutive rectal or colon cancer cases with synchronous liver-only metastasis was conducted from the South Australian Colorectal Cancer Registry from 2006 to 2021. This study aimed to investigate how order and type of treatment modality affects overall survival.

RESULTS

Data of over 5000 cases were analysed (n = 5244), 1420 cases had liver-only metastasis. There were a greater number of colon than rectal primaries (N = 1056 versus 364). Colonic resection was the preferred initial treatment for the colon cohort (60%). In the rectal cohort, 30% had upfront resection followed by 27% that had chemo-radiotherapy as 1st line therapy. For the colon cohort, there was an improved 5-year survival with surgical resection as initial treatment compared to chemotherapy (25% versus 9%, P < 0.001). In the rectal cohort, chemo-radiotherapy as the initial treatment was associated with an improved 5-year survival compared to surgery or chemotherapy (40% versus 26% versus 19%, P = 0.0015). Patients who were able to have liver resection had improved survival, with 50% surviving over 5 years compared to 12 months in the non-resected group (P < 0.001). Primary rectal KRAS wildtype patients who underwent liver resection and received Cetuximab had significantly worse outcomes compared to KRAS wildtype patients who did not (P = 0.0007).

CONCLUSIONS

Where surgery is possible, resection of liver metastasis and primary tumour improved overall survival. Further research is required on the use of targeted treatments in patients undergoing liver resection.

Prognostic Impact of Surgical Margin Width in Hepatectomy for Colorectal Liver Metastasis

As for resection for colorectal liver metastasis (CRLM), securing an adequate surgical margin is important for achieving a better prognosis. However, it is often difficult to achieve adequate margins for the resection of CRLM. So the current survival impact of sub-centi/millimeter surgical margins in hepatectomy for CRLM should be evaluated. In the current era of multidisciplinary treatment options, this review focused on the prognostic impact of a sub-centi/millimeter surgical margin width in hepatectomy for CRLM. We systematically reviewed retrospective studies that clearly described the surgical margin width for hepatectomy for CRLM. We selected studies conducted since 2000 that involved patients diagnosed as having CRLM. We focused on studies that investigated not only surgical margins, but also microscopic surgical curability such as R0 (microscopically complete resection) or R1 (microscopically incomplete resection), which clearly describe their definitions. Based on our literature review, 1, 2, or 5 mm was considered the minimum surgical margin width for hepatectomy for CRLM. Although a surgical margin width of 1 mm is acceptable for hepatectomy for CRLM, submillimeter margins, which are defined as R1 in many reports, are only acceptable for limited patients such as those who have undergone preoperative chemotherapy. Zero-mm margins are also acceptable in limited patients such as those who show a good response to preoperative chemotherapy. New chemotherapy agents have been reported to reduce the prognostic impact of a narrow surgical margin width. The incidence of margin recurrence, which is a major concern regarding R1 resection of CRLM, is about 20-30% according to the majority of earlier reports. As evaluations of the actual prognostic impact of the surgical margin remain difficult, further study is warranted.

Tumor attachment to Major intrahepatic vascular for Colorectal liver metastases

BACKGROUND

Colorectal liver metastases attached major intrahepatic vessels has been considered to be a risk factor for survival outcome after liver resection. The present study aimed to clarify the outcomes of R1 surgery (margin < 1 mm) in CRLM patients, distinguishing parenchymal margin R1 and attached to major intrahepatic vessels R1.

METHODS

In present study, 283 CRLM patients who were evaluated to be attached to major intrahepatic vessels initially and underwent liver resection following preoperative chemotherapy. They were assigned to two following groups: R0 (n = 167), R1 parenchymal (n = 58) and R1 vascular (n = 58). The survival outcomes and local recurrence rates were analyzed in each group.

RESULTS

Overall, 3- and 5-year overall survival rates after liver resection were 53.0% and 38.2% (median overall survival 37 months). Five-year overall survival was higher in patients with R0 than parenchymal R1 (44.9%% vs. 26.3%, p = 0.009), whereas there was no significant difference from patients with vascular R1 (34.3%, p = 0.752). In the multivariable analysis, preoperative chemotherapy > 4 cycles, clinical risk score 3-5, RAS mutation, parenchymal R1 and CA199 > 100 IU/ml were identified as independent predictive factors of overall survival (p < 0.05). There was no significant difference for local recurrence among three groups.

CONCLUSION

Parenchymal R1 resection was independent risk factor for CRLM. Vascular R1 surgery achieved survival outcomes equivalent to R0 resection. Non-anatomic liver resection for CRLM attached to intrahepatic vessels might be pursued to increase patient resectability by preoperative chemotherapy.

Prognostic impact of R1 resection margin in synchronous and simultaneous colorectal liver metastasis resection: a retrospective cohort study

BACKGROUND

A margin ≥ 1 mm is considered a standard resection margin for colorectal liver metastasis (CRLM). However, microscopic incomplete resection (R1) is not rare since aggressive surgical resection has been attempted in multiple and bilobar CRLM. This study aimed to investigate the prognostic impact of resection margins and perioperative chemotherapy in patients with CRLM.

METHODS

A total of 368 of 371 patients who underwent simultaneous colorectal and liver resection for synchronous CRLM between 2006 and June 2017, excluding three R2 resections, were included in this study. R1 resection was defined as either abutting tumor on the resection line or involved margin in the pathological report. The patients were divided into R0 (n = 304) and R1 (n = 64) groups. The clinicopathological characteristics, overall survival, and intrahepatic recurrence-free survival were compared between the two groups using propensity score matching.

RESULTS

The R1 group had more patients with ≥ 4 liver lesions (27.3 vs. 50.0%, P < 0.001), higher mean tumor burden score (4.4 vs. 5.8%, P = 0.003), and more bilobar disease (38.8 vs. 67.2%, P < 0.001) than the R0 group. Both R0 and R1 groups showed similar long-term outcomes in the total cohort (OS, P = 0.149; RFS, P = 0.414) and after matching (OS, P = 0.097, RFS: P = 0.924). However, the marginal recurrence rate was higher in the R1 group than in the R0 group (26.6 vs. 16.1%, P = 0.048). Furthermore, the resection margin did not have a significant impact on OS and RFS, regardless of preoperative chemotherapy. Poorly differentiated, N-positive stage colorectal cancer, liver lesion number ≥ 4, and size ≥ 5 cm were poor prognostic factors, and adjuvant chemotherapy had a positive impact on survival.

CONCLUSIONS

The R1 group was associated with aggressive tumor characteristics; however, no effect on the OS and intrahepatic RFS with or without preoperative chemotherapy was observed in this study. Tumor biological characteristics, rather than resection margin status, determine long-term prognosis. Therefore, aggressive surgical resection should be considered in patients with CRLM expected to undergo R1 resection in this multidisciplinary approach era.

Comprehensive data of 4502 patients newly diagnosed with colorectal liver metastasis between 2015 and 2017, and prognostic data of 2427 patients newly diagnosed with colorectal liver metastasis in 2013 and 2014: Third report of a nationwide survey in Japan

To improve treatment outcomes in patients with colorectal liver metastasis (CRLM), the Joint Committee for Nationwide Survey on CRLM was established by the Japanese Society for Cancer of the Colon and Rectum and the Japanese Society of Hepato-Biliary-Pancreatic Surgery. The aim of the study was to evaluate transition in the characteristics and treatment strategy in CRLM patients and analyze prognostic factors using large-scale data. The present study summarizes the data of patients newly diagnosed between 2015 and 2017 and presents prognostic data of patients newly diagnosed in 2013 and 2014. Survival curves were generated by the Kaplan-Meier method and compared by log-rank test. Multivariate analyses were carried out using Cox proportional hazard modeling. The data of 4502 patients newly diagnosed with CRLM between 2015 and 2017 and the prognostic data of 2427 patients diagnosed in 2013 and 2014 are included. Regarding the 2013 and 2014 prognostic data, the 5-year overall survival (OS) rates of patients who underwent hepatectomy alone was 59.8%. Multivariate analyses identified age at diagnosis of CRLM ≥70 years, concomitant extrahepatic metastasis at diagnosis of CRLM, tumor depth of primary lesion ≥subserosa/pericolic or perirectal tissue, mutant KRAS status, number of CRLM ≥5, maximum diameter of CRLM >5 cm, and surgical curability R1/R2 as independent predictors of OS. Analysis of the latest nationwide database of patients diagnosed with CRLM revealed changes in patients and oncological characteristics, a transition in treatment strategy, and different independent prognosticators to those reported previously.

Pushing the Limits of Surgical Resection in Colorectal Liver Metastasis: How Far Can We Go?

Colorectal cancer is the third most common cancer worldwide, and up to 50% of all patients diagnosed will develop metastatic disease. Management of colorectal liver metastases (CRLM) has been constantly improving, aided by newer and more effective chemotherapy agents and the use of multidisciplinary teams. However, the only curative treatment remains surgical resection of the CRLM. Although survival for surgically resected patients has shown modest improvement, this is mostly because of the fact that what is constantly evolving is the indication for resection. Surgeons are constantly pushing the limits of what is considered resectable or not, thus enhancing and enlarging the pool of patients who can be potentially benefited and even cured with aggressive surgical procedures. There are a variety of procedures that have been developed, which range from procedures to stimulate hepatic growth, such as portal vein embolization, two-staged hepatectomy, or the association of both, to technically challenging procedures such as simultaneous approaches for synchronous metastasis, ex-vivo or in-situ perfusion with total vascular exclusion, or even liver transplant. This article reviewed the major breakthroughs in liver surgery for CRLM, showing how much has changed and what has been achieved in the field of CRLM.

Does Using Indocyanine Green Fluorescence Imaging for Tumors Help in Determining the Safe Surgical Margin in Real-Time Navigation of Laparoscopic Hepatectomy? A Retrospective Study

BACKGROUND

This study aims to investigate whether indocyanine green (ICG) tumor imaging helps determine the safe surgical margin in laparoscopic hepatectomy.

PATIENTS AND METHODS

Eighty-six patients with hepatic malignancies [including hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM)] were included in this study. ICG-R15 testing was performed 5-7 days before surgery. Fluorescence staining of the tumor was detected by a fluorescent laparoscope, and the width of fluorescence band surrounding tumor was measured by an electronic vernier caliper.

RESULTS

The positive rate of hepatic malignant lesions successfully stained by ICG fluorescence was 96.0% (95/99). HCC with better differentiation demonstrated non-rim fluorescence patterns, while cases with poor differentiation demonstrated rim patterns. CRLM uniformly demonstrated rim pattern. The width of fluorescence surrounding tumors was 0 in HCC with non-rim patterns. The minimum width of fluorescence surrounding tumors in poor differentiated HCC and CRLM were 2.4 ± 1.9 mm and 2.8 ± 2.5 mm, respectively, with no significant difference (P > 0.05). ICG fluorescence imaging revealed eight small lesions, which were not detected preoperatively in seven patients, of which five lesions were confirmed as malignancies by pathology.

CONCLUSIONS

Resection along the ICG fluorescence edge can supply a safe surgical margin only for CRLM, but not for HCC. Otherwise, ICG fluorescence tumor imaging can preliminarily determine the pathological type of hepatic malignancies and histological differentiation of HCC and help detect small lesions that cannot be detected preoperatively.

Multiple colorectal liver metastases resection can offer long-term survival: The concept of a chronic neoplastic disease

BACKGROUND

Resection for colorectal liver metastases has evolved significantly and, currently, there are no limits to the number of resected nodules. This study aimed to evaluate the outcomes and prognostic factors after liver resection for patients with ≥4 colorectal liver metastases, emphasizing long-term survival.

METHODS

The study population consisted of 137 patients with ≥4 colorectal liver metastases out of a total of 597 patients with colorectal liver metastases who underwent curative intent liver resection from January 2010 to July 2019 in a single hepatobiliary center.

RESULTS

The probability of overall and disease-free survival at 1, 3, and 5 years was 90.8%, 64.5%, 40.6%, and 37.7%, 19.3%, 18.1%, respectively. In a multivariate analysis for overall survival, the size of the largest metastatic nodule was the only unfavorable factor (P = .001). For disease-free survival, complete pathological response was a favorable factor (P = .04), and the following were negative factors: number of nodules ≥7 (P = .034), radiofrequency ablation during surgery (P = .04), positive primary tumor lymph nodes (P = .034), R1 resection (P = .011), and preoperative carcinoembryonic antigen >20 ng/mL (P = .015). After the first and second years of follow-up, 59 patients (45.3%) and 45 patients (34.6%), respectively, were not receiving chemotherapy. After 5 years of follow-up, 21 (16.1%) multimetastatic patients were chemotherapy-free.

CONCLUSION

A significant number of patients with multiple colorectal liver metastases will present long-term survival and should not be denied surgery. The long-term survival rates, even in the presence of recurrence, characterize a chronic neoplastic disease.

Imaging Features of Main Hepatic Resections: The Radiologist Challenging

Liver resection is still the most effective treatment of primary liver malignancies, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), and of metastatic disease, such as colorectal liver metastases. The type of liver resection (anatomic versus non anatomic resection) depends on different features, mainly on the type of malignancy (primary liver neoplasm versus metastatic lesion), size of tumor, its relation with blood and biliary vessels, and the volume of future liver remnant (FLT). Imaging plays a critical role in postoperative assessment, offering the possibility to recognize normal postoperative findings and potential complications. Ultrasonography (US) is the first-line diagnostic tool to use in post-surgical phase. However, computed tomography (CT), due to its comprehensive assessment, allows for a more accurate evaluation and more normal findings than the possible postoperative complications. Magnetic resonance imaging (MRI) with cholangiopancreatography (MRCP) and/or hepatospecific contrast agents remains the best tool for bile duct injuries diagnosis and for ischemic cholangitis evaluation. Consequently, radiologists should be familiar with the surgical approaches for a better comprehension of normal postoperative findings and of postoperative complications.

Analysis of survival factors after hepatic resection for colorectal cancer liver metastases: Does the R1 margin matter?

Introduction

The effect of liver margin on colorectal cancer liver metastases (CRLM) after hepatectomy has been controversial. In this study, we conducted a postoperative follow-up study of 205 patients with CRLM to clarify whether a positive margin is significant and to define the risk factors affecting CRLM survival.

Methods

The data of 205 patients with CRLM who underwent surgical treatment at the Third Hospital of Peking University in the Department of General Surgery from January 2009 to December 2020 were retrospectively analyzed. The general data, surgical data and postoperative follow-up of the patients were statistically analyzed.

Results

There were 130 cases (63.4%) of R0 resection and 75 cases (36.6%) of R1 resection. There were 136 males and 69 females, age 61 ± 11 years, and body mass index (BMI 24.5 ± 3.3 kg/m²). The overall survival rates at 1, 3, and 5 years for the entire cohort were 93.4%, 68.4%, and 45.5% in the R0 resection group vs. 93.2%, 53.7%, and 42% in the R1 resection group, respectively, which were not statistically significant (P = 0.520). The 1-, 3-, and 5-year disease-free survival rates of 63.2%, 33.3%, and 29.7% were significantly better in the R0 resection group than in the R1 resection group of 47.9%, 22.7%, and 17.7% (P = 0.016), respectively. After multivariable analysis, carbohydrate antigen 19-9 (CA19-9) > 39 U/ml (HR = 2.29, 95% CI: 1.39-3.79, P = 0.001), primary tumor perineural invasion (HR = 1.78, 95% CI: 1.01-3.13, P = 0.047), and BMI > 24 kg/m2 (HR = 1.75, 95% CI: 1.05-2.93, P = 0.033) were independently associated with poorer overall patient survival. The number of liver metastases >2 (HR = 1.65, 95% CI: 1.10-2.47, P = 0.016), the maximum diameter of metastases ≥50 mm (HR = 1.67, 95% CI: 1.06-2.64, P = 0.026), and vascular invasion of the primary tumor (HR = 1.65, 95% CI: 1.03-2.64, P = 0.038) were also independently associated with poorer disease-free survival.

Conclusion

In patients undergoing hepatectomy for CRLM, the negative effect of the R1 margin should be downplayed, and although the disease-free survival of the R1 margin is shorter than that of the R0 margin, it has no impact on overall survival. To improve overall survival, extra attention should be given to the factors of preoperative BMI, preoperative CA19-9, and the presence of perineural invasion of the primary tumor.

Tumor biology reflected by histological growth pattern is more important than surgical margin for the prognosis of patients undergoing resection of colorectal liver metastases

INTRODUCTION

The histological growth pattern (HGP) of colorectal liver metastases (CRLMs) reflects tumor biology and local infiltrating behavior. In patients undergoing surgery for CRLMs, we investigated whether HGP and surgical margin status interact when influencing prognosis.

METHODS

Clinicopathological data, margin status, and HGP were reviewed in patients who underwent resection of CRLMs. R1 margin was defined when cancer cells were present at any point along the margin. HGPs were scored according to international guidelines, identifying patients with desmoplastic (DHGP) or non-desmoplastic (non-DHGP) CRLMs.

RESULTS

Among 299 patients, 16% had R1 resection and 81% had non-DHGP CRLMs. Non-DHGP was the only predictive factor for R1 resection (18.7% versus 7.4% in DHGP, p = 0.04). Poorer 5-year overall survival was observed in both R1 and non-DHGP groups in univariate analysis (27.6% in R1 versus 45.6% in R0, p = 0.026, and 37.2% in non-DHGP versus 59.2% in DHGP, p = 0.013), whereas non-DHGP but not R1 remained associated with worse prognosis in multivariate analysis. In patients with non-DHGP, R1 margin has no prognostic impact.

CONCLUSIONS

In patients undergoing resection of CRLMs, the prognostic value of poor tumor biology, such as in patients with non-DHGP, exceeds that of surgical radicality.

Colorectal Cancer Liver Metastases: Is an R1 Hepatic Resection Accepted?

Metastatic colorectal cancer is associated with a rather dismal 5-year overall survival. The liver is the most commonly affected organ. Improved 5-year survival rates after successful hepatic resections for metastases confined to the liver have been reported. Certainly, a hepatectomy that results in an incomplete tumor resection, in terms of leaving macroscopic residual tumor in the future liver remnant, is not associated with survival benefits. However, the prognostic implications of a microscopically positive surgical margin or a clear margin of less than 1 mm (R1) on pathology are debatable. Although it has been a field of extensive research, the relevant literature often reports contradictory results. The purpose of the present study was to define, assess the risk factors for, and, ultimately, analyze the effect that an R1 hepatic resection for colorectal cancer liver metastases might have on local recurrence rates and long-term prognosis by reviewing the relevant literature. Achieving an R0 hepatic resection, optimally with more than 1 mm of clear margin, should always be the goal. However, in the era of the aggressive multimodality treatment of liver metastatic colorectal cancer, an R1 resection might be the cost of increasing the pool of patients finally eligible for resection. The majority of literature reports have highlighted the detrimental effect of R1 resections on local recurrence and overall survival. However, there are indeed studies that degraded the prognostic handicap as a consequence of an R1 resection in selected patients and highlighted the presence of RAS mutations, the response to chemotherapy, and, in general, factors that reflect the biology of the disease as important, if not the determinant, prognostic factors. In these patients, the aggressive disease biology seems to outperform the resection margin status as a prognostic factor, and the recorded differences between R1 and R0 resections are equalized. Properly and accurately defining this patient group is a future challenge in the field of the surgical treatment of colorectal cancer liver metastases.

Oncologic aspects of the decision-making process for surgical approach for colorectal liver metastases progressing during chemotherapy

Colorectal cancer represents the third most diagnosed malignancy in the world. The liver is the main site of metastatic disease, affected in 30% of patients with newly diagnosed disease. Complete resection is considered the only potentially curative treatment for colorectal liver metastasis (CRLM), with a 5-year survival rate ranging from 35% to 58%. However, up to 80% of patients have initially unresectable disease, due to extrahepatic disease or bilobar multiple liver nodules. The availability of increasingly effective systemic chemotherapy has contributed to converting patients with initially unresectable liver metastases to resectable disease, improving long-term outcomes, and accessing tumor biology. In recent years, response to preoperative systemic chemotherapy before liver resection has been established as a major prognostic factor. Some studies have demonstrated that patients with regression of hepatic metastases while on chemotherapy have improved outcomes when compared to patients with stabilization or progression of the disease. Even if disease progression during chemotherapy represents an independent negative prognostic factor, some patients may still benefit from surgery, given the role of this modality as the main treatment with curative intent for patients with CRLM. In selected cases, based on size, the number of lesions, and tumor markers, surgery may be offered despite the less favorable prognosis and as an option for non-chemo responders.

Precision surgery for colorectal liver metastases: Current knowledge and future perspectives

Precision surgery for colorectal liver metastases (CRLM) includes optimal selection of both the patient and surgery. Initial attempts of using clinical risk scores to identify patients for whom technically feasible surgery is oncologically futile failed. Since then, patient selection for single-stage hepatectomy followed three distinct approaches, all of which incorporated biomarkers. The BRAF V600E mutation, the G12V KRAS variant, and the triple mutation of RAS, TP53, and SMAD4 appear to be the most promising, but none can be used in isolation to deny surgery in otherwise resectable cases. Combining biomarkers with clinicopathologic factors that predict poor prognosis may be used to select patients for surgery, but external validation and matched analyses with medically treated counterparts are needed. Patient selection for special surgical procedures (two-stage hepatectomy [TSH], Associating Liver Partition and Portal vein Ligation for staged hepatectomy [ALPPS], and liver transplant [LT]) has been recently refined. Specifically, BRAF mutations and right-sided laterality have been proposed as separate contraindications to LT. A similar association of right-sided laterality, particularly when combined with RAS mutations, with very poor outcomes has been observed for ALPPS and has been suggested as a biologic contraindication. Data are scarce for TSH but RAS mutations may portend very poor survival following TSH completion. The selection of the best single-stage hepatectomy (optimal margin and type of resection) based on biomarkers remains debated, although there is some evidence that RAS may play a significant role. Lastly, although there are currently no criteria to select among the three special techniques based on their efficacy or appropriateness in different settings, RAS mutational status may be used to select patients for TSH, while right-sided tumor in conjunction with a RAS mutation may be a contraindication to LT and ALPPS.

Role of stereotactic body radiotherapy in multidisciplinary management of liver metastases in patients with colorectal cancer

In the treatment of colorectal cancer patients with distant metastases, the development of new anticancer agents has considerably prolonged progression-free survival. Such survival benefits attributed to chemotherapy have increased the relative significance of local therapy in patients with limited metastases. The liver is recognized as the most common site of metastasis of colorectal cancer because of the intestinal mesenteric drainage to the portal veins. Hepatic resection of isolated liver metastases of colorectal cancer is the only option for a potential cure. However, hepatic metastases are resectable in only approximately 20% of the patients. For remaining patients with high-risk resectable liver metastases or those who are unfit for surgery, less invasive, local therapies including radiation therapy (stereotactic body radiation therapy, SBRT) may have a potential role in treatment. Although the local control rate of SBRT for colorectal liver metastases has room for improvement, its less-invasive nature and broad indications deserve consideration. Future research should include SBRT dose escalation or the selection of patients who benefit from local ablative therapies. SBRT may offer an alternative, non-invasive approach for the treatment of colorectal liver metastases in a multidisciplinary treatment strategy.

Brazilian Society of Surgical Oncology surgical standards for resectable colorectal cancer liver metastases

The management of colorectal cancer liver metastasis (CRLM) has become complex because of the increasing availability of medical, radiological, and surgical treatment options applied either alone or in combination. However, resection remains the only evidence-based curative therapy. These Brazilian Society of Surgical Oncology surgical standards are intended to guide clinicians in the decision-making process for modern surgical management of CRLM within a multidisciplinary team in an evidence-based framework, focusing on resectable disease.

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.

Efficacy and Safety of mFOLFOX6 as Perioperative Chemotherapy for Resectable Liver Metastases from Colorectal Cancer: A Case-Control Study

BACKGROUND/AIM

Although resection is effective for managing resectable liver metastases from colorectal cancer, the clinical significance of chemotherapy for such metastases has remained undetermined. Therefore, we conducted a phase II trial of perioperative chemotherapy with mFOLFOX6 to examine its efficacy.

PATIENTS AND METHODS

A total of 41 patients were examined. The liver resection rate was the primary endpoint, whereas the response rate, adverse events, completion rate, liver injury rate, R0 resection rate, and histological results were the secondary endpoints.

RESULTS

Overall, 34 (82.9%) patients underwent liver resection, and 77.4% and 100% had synchronous and metachronous liver metastases, respectively. The seven remaining patients did not undergo resection because of progressive disease. Moreover, 2, 15, 17, and 7 patients had a complete response, partial response, stable disease, and progressive disease, respectively, which indicated that the response rate was 41.5%. Regarding adverse events, three patients exhibited Grade 3 myelosuppression and one patient had gastrointestinal symptoms. On the basis of histopathological examination, 27, 5, and 2 patients belonged to grades 1a:1b, 2, and 3, respectively. Regarding liver injury, 29.4% had liver sinusoidal injury, whereas 11.7% had steatohepatitis. Meanwhile, all patients underwent postoperative chemotherapy.

CONCLUSION

mFOLFOX6 is safe and yields favorable therapeutic effects. The indication for liver resection after a certain waiting period is clinically significant.

The management of colorectal liver metastases amenable of surgical resection: How to shape treatment strategies according to clinical, radiological, pathological and molecular features

Metastatic colorectal cancer (mCRC) patients have poor chances of long term survival, being < 15% of them still alive after 5 years from diagnosis. Nonetheless, patients with colorectal liver metastases (CRLM) may be eligible for metastases resection thus being able to achieve long-term disease remission and survival. The likelihood for patients with CRLM of being or becoming eligible for liver metastasectomy is increasing, thanks to the evolution of surgical techniques, the availability of active systemic treatments and the widespread diffusion of experienced multidisciplinary boards to manage these patients. However, disease relapse after liver surgery is common and occurs in two-thirds of resected patients. Therefore, adequate radiological staging and risk stratification is crucial for the optimal selection of patients candidate to surgery in order to maximize the benefit-risk ratio of liver metastasectomy and to individualize the treatment strategy. Based on the multidimensional assessment, three possible approaches are available: upfront liver surgery followed by adjuvant chemotherapy, perioperative chemotherapy preceding and following liver surgery, and an upfront systemic treatment including chemotherapy plus a targeted agent, both chosen according to patients' and tumours' characteristics, then followed by liver surgery if indicated. In this review, we describe the most important factors impacting the therapeutic choices in patients with resectable and potentially resectable CRLM, and we discuss the most promising factors that may reshape the future decision-making process of these patients.

Histopathological factors versus margin size in single colorectal liver metastases: Does a 1-cm margin size matter?

Background and objective:

The ideal margin width for surgical resection of colorectal liver metastases has been extensively studied, but not sufficiently in accordance with other pathological factors. The aim of this study was to assess for the first time the prognostic impact of margin widths according to different prognostic pathological factors in colorectal liver metastasis.

Methods:

We evaluated 101 patients with a single resected metastasis. Slides stained by HE were assessed for the presence of poorly differentiated clusters, peritumoral inflammatory infiltrate, tumor pseudocapsule, and tumor borders pattern. Overall survival, disease-free survival, and hepatic recurrence were evaluated. The pathologic factors prognostic impact was evaluated according to a (< or ⩾) 10-mm margin size.

Results:

Factors independently associated with a shorter overall survival were absence of tumor pseudocapsule ( p < 0.001) and infiltrative tumor border pattern ( p = 0.019). The absence of tumor pseudocapsule was the only factor independently associated with shorter disease-free survival ( p < 0.001). Hepatic recurrence was associated with infiltrative tumor border and absence of pseudocapsule. Margin width ⩾10 mm did not impact overall survival independently of the studied histological prognostic factors.

Conclusions:

In colorectal liver metastasis resection, the absence of tumor pseudocapsule was significantly associated with shorter overall survival and disease-free survival and hepatic recurrence. However, margins larger than 10 mm did not offer survival benefit when other pathologic negative prognostic factors were concomitantly analyzed, reinforcing the idea that biology, rather than margin size, is crucial for prognosis.

Upper transversal hepatectomy with double hepatic vein resection and reconstruction to treat colorectal cancer liver metastases at the hepatocaval confluence: a strategy to achieve R0 liver-sparing resection

BACKGROUND

Repeated hepatectomies in the therapeutic route of patients with colorectal liver metastases (CRLM) may improve their long term survival. Hepatic vein (HV) resection and reconstruction allows parenchyma-sparing hepatectomy (PSH) and R0 resections for CRLM in contact with one HV. We aimed at verifying the feasibility of PSH with double HV resection and direct reconstruction for CRLM in contact with two HVs at the hepatocaval confluence.

METHODS

Out of 106 consecutive PSH performed for CRLM deep-located in segments I-IVa-VII-VIII, four (3.7%) PSH were performed with resection of CRLM en bloc with two adjacent HVs which were both reconstructed with double direct HV anastomosis: 3 cases between right-HV and middle-HV and 1 case between middle-HV and left-HV. Two patients had previously undergone liver resection. Three patients had one single lesion and one had 5 CRLMs.

RESULTS

Median size of CRLMs in contact with HVs was 25 mm (range 22-30 mm). At histological examination, all resections were R0 except one R1-vascular (detachment from glissonean pedicle): in all cases at least one HV and in 1 case both HVs were infiltrated by the tumor cells. After median follow-up of 18 (range 3.5-41.2) months, all HVs were patent. All patients were alive and in good general conditions, and 3 patients were disease free (one of them following a liver re-resection). One patient experienced a grade IIIa complication. Median hospital-stay was 11 (range 9-13) days.

CONCLUSION

In patients with CRLMs involving two adjacent HVs at the hepatocaval confluence, liver resection with double HV resection and direct reconstruction is feasible and may be considered to guarantee oncological radicality (R0) and spare health parenchyma.

Shifting concepts in the management of colorectal liver metastases

Management of patients with colorectal liver metastases has evolved considerably due to a better understanding of the biology of the disease with concurrent improvements in surgical techniques, oncological strategies and radiological interventions. This review article examines the factors that have contributed to this radical change. Management will be discussed in relation to chemotherapy, surgery and interventional radiology. The addition of chemotherapy and biological agents has greatly extended the reach and scope of surgery. Parenchymal sparing resections, repeat resections, two stage hepatectomy and Associating Liver Partition and Portal Vein ligation are all available to the hepatobiliary surgeon who deals with colorectal liver metastases. Interventional radiology techniques like liver venous deprivation may also replace established surgical practice. Whilst traditionally it was thought that only a few liver metastases could be treated effectively, nowadays tumour number is no longer a limiting factor provided enough functioning liver can be spared and the patient can tolerate the operation.