Outcome of microscopic incomplete resection (R1) of colorectal liver metastases in the era of neoadjuvant chemotherapy

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.

Evaluation of two-stage hepatectomy using portal vein embolization for colorectal liver metastasis: a retrospective nationwide cohort survey in Japan

INTRODUCTION

Two-stage hepatectomy (TSH) enables patients to undergo surgery for colorectal liver metastasis (CRLM), which one-stage hepatectomy cannot remove. Although the outcome of TSH has been reported, there is no original report from Japan. The aim of this retrospective study was to evaluate the outcome of TSH in Japanese patients with CRLM.

METHODS

The authors conducted a retrospective cohort study using the nationwide database that included clinical information of 12 519 patients treated with CRLM between 2005 and 2017 in Japan. The primary outcome measure was overall survival. The second outcome measure was progression-free survival. Fisher's exact test, χ 2 test and Mann-Whitney U test were conducted to examine an intergroup difference. Univariate and multivariate analyses were performed using Cox regression model. Survival analysis was performed by Kaplan-Meier method and log-rank test.

RESULTS

Of the database, 53 patients undergoing TSH using portal vein embolization (PVE) were identified and analyzed. Their morbidity and in-hospital mortality rates at the second hepatectomy were 26.4% and 0.0%. The mean observation period was 21.8 months. The estimated 1-, 3- and 5-year overall survival rate were 92.5%, 70.8% and 34.7%. Multivariate analyses showed that more than 10 liver nodules significantly increased the mortality risk by 4.2-fold (95% CI 1.224-14.99, P = 0.023). Survival analysis revealed that repeat hepatectomy for disease progression after TSH was superior to chemotherapy in overall survival (mean: 49.6 vs. 18.7, months, P = 0.004).

CONCLUSION

In the Japanese cohort, TSH was confirmed to be a safety procedure with an acceptable survival outcome. More than 10 liver nodules may be a predictor for unfavorable outcomes of patients with CRLM undergoing TSH. Furthermore, repeat hepatectomy can be a salvage treatment for resectable intrahepatic recurrence after TSH.

Radiomic Gradient in Peritumoural Tissue of Liver Metastases: A Biomarker for Clinical Practice? Analysing Density, Entropy, and Uniformity Variations with Distance from the Tumour

The radiomic analysis of the tissue surrounding colorectal liver metastases (CRLM) enhances the prediction accuracy of pathology data and survival. We explored the variation of the textural features in the peritumoural tissue as the distance from CRLM increases. We considered patients with hypodense CRLMs >10 mm and high-quality computed tomography (CT). In the portal phase, we segmented (1) the tumour, (2) a series of concentric rims at a progressively increasing distance from CRLM (from one to ten millimetres), and (3) a cylinder of normal parenchyma (Liver-VOI). Sixty-three CRLMs in 51 patients were analysed. Median peritumoural HU values were similar to Liver-VOI, except for the first millimetre around the CRLM. Entropy progressively decreased (from 3.11 of CRLM to 2.54 of Liver-VOI), while uniformity increased (from 0.135 to 0.199, p < 0.001). At 10 mm from CRLM, entropy was similar to the Liver-VOI in 62% of cases and uniformity in 46%. In small CRLMs (≤30 mm) and responders to chemotherapy, normalisation of entropy and uniformity values occurred in a higher proportion of cases and at a shorter distance. The radiomic analysis of the parenchyma surrounding CRLMs unveiled a wide halo of progressively decreasing entropy and increasing uniformity despite a normal radiological aspect. Underlying pathology data should be investigated.

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.

ICG-Fluorescence Imaging for Margin Assessment During Minimally Invasive Colorectal Liver Metastasis Resection

Importance

Unintended tumor-positive resection margins occur frequently during minimally invasive surgery for colorectal liver metastases and potentially negatively influence oncologic outcomes.

Objective

To assess whether indocyanine green (ICG)-fluorescence-guided surgery is associated with achieving a higher radical resection rate in minimally invasive colorectal liver metastasis surgery and to assess the accuracy of ICG fluorescence for predicting the resection margin status.

Design, Setting, and Participants

The MIMIC (Minimally Invasive, Indocyanine-Guided Metastasectomy in Patients With Colorectal Liver Metastases) trial was designed as a prospective single-arm multicenter cohort study in 8 Dutch liver surgery centers. Patients were scheduled to undergo minimally invasive (laparoscopic or robot-assisted) resections of colorectal liver metastases between September 1, 2018, and June 30, 2021.

Exposures

All patients received a single intravenous bolus of 10 mg of ICG 24 hours prior to surgery. During surgery, ICG-fluorescence imaging was used as an adjunct to ultrasonography and regular laparoscopy to guide and assess the resection margin in real time. The ICG-fluorescence imaging was performed during and after liver parenchymal transection to enable real-time assessment of the tumor margin. Absence of ICG fluorescence was favorable both during transection and in the tumor bed directly after resection.

Main Outcomes and Measures

The primary outcome measure was the radical (R0) resection rate, defined by the percentage of colorectal liver metastases resected with at least a 1 mm distance between the tumor and resection plane. Secondary outcomes were the accuracy of ICG fluorescence in detecting margin-positive (R1; <1 mm margin) resections and the change in surgical management.

Results

In total, 225 patients were enrolled, of whom 201 (116 [57.7%] male; median age, 65 [IQR, 57-72] years) with 316 histologically proven colorectal liver metastases were included in the final analysis. The overall R0 resection rate was 92.4%. Re-resection of ICG-fluorescent tissue in the resection cavity was associated with a 5.0% increase in the R0 percentage (from 87.4% to 92.4%; P < .001). The sensitivity and specificity for real-time resection margin assessment were 60% and 90%, respectively (area under the receiver operating characteristic curve, 0.751; 95% CI, 0.668-0.833), with a positive predictive value of 54% and a negative predictive value of 92%. After training and proctoring of the first procedures, participating centers that were new to the technique had a comparable false-positive rate for predicting R1 resections during the first 10 procedures (odds ratio, 1.36; 95% CI, 0.44-4.24). The ICG-fluorescence imaging was associated with changes in intraoperative surgical management in 56 (27.9%) of the patients.

Conclusions and Relevance

In this multicenter prospective cohort study, ICG-fluorescence imaging was associated with an increased rate of tumor margin-negative resection and changes in surgical management in more than one-quarter of the patients. The absence of ICG fluorescence during liver parenchymal transection predicted an R0 resection with 92% accuracy. These results suggest that use of ICG fluorescence may provide real-time feedback of the tumor margin and a higher rate of complete oncologic resection.

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.

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.

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.

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.

Label-free multiphoton microscopy enables histopathological assessment of colorectal liver metastases and supports automated classification of neoplastic tissue

As the state of resection margins is an important prognostic factor after extirpation of colorectal liver metastases, surgeons aim to obtain negative margins, sometimes elaborated by resections of the positive resection plane after intraoperative frozen sections. However, this is time consuming and results sometimes remain unclear during surgery. Label-free multimodal multiphoton microscopy (MPM) is an optical technique that retrieves morpho-chemical information avoiding all staining and that can potentially be performed in real-time. Here, we investigated colorectal liver metastases and hepatic tissue using a combination of three endogenous nonlinear signals, namely: coherent anti-Stokes Raman scattering (CARS) to visualize lipids, two-photon excited fluorescence (TPEF) to visualize cellular patterns, and second harmonic generation (SHG) to visualize collagen fibers. We acquired and analyzed over forty thousand MPM images of metastatic and normal liver tissue of 106 patients. The morphological information with biochemical specificity produced by MPM allowed discriminating normal liver from metastatic tissue and discerning the tumor borders on cryosections as well as formalin-fixed bulk tissue. Furthermore, automated tissue type classification with a correct rate close to 95% was possible using a simple approach based on discriminant analysis of texture parameters. Therefore, MPM has the potential to increase the precision of resection margins in hepatic surgery of metastases without prolonging surgical intervention.

Defining a textbook outcome for the resection of colorectal liver metastases

INTRODUCTION

Textbook outcomes (TBO) are composite measures of care which may be superior in assessing quality compared to traditional methods. We aim to define TBO which are specific to surgical resection of colorectal liver metastases, and investigate their impact on survival.

METHODS

Single center analysis of all liver resections performed at our center from 2009 to 2020. A Cox model was used to identify perioperative outcomes which impacted on overall survival. These were retained with important postoperative outcomes to form a "TBO." The impact of a TBO on overall survival was investigated using Kaplan-Meier curve analysis.

RESULTS

TBO was achieved in 72.2% (197/273) of resections. Major morbidity (Clavien-Dindo ≥3) at 19.4% was the major limiting factor in not achieving a TBO. TBO was associated with improved 3-year (77% vs. 55%), 5-year (60.7% vs. 42.5%), and median (93 vs. 44 months) overall survival (log-rank test, p = 0.006). Multivariable analysis revealed age >65 years, American Society of Anaesthesiologists Grade III-IV, and resection of >2 segments as factors predictive of not achieving a TBO.

CONCLUSION

TBO is a useful composite measure in surgery for colorectal liver metastases. It can highlight areas which may be targeted for quality improvement and be useful as a tool to examine variation between centers. Achieving a TBO is associated with a significant improvement in survival.

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.

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.

Defining Textbook Outcome in liver surgery and assessment of hospital variation: A nationwide population-based study

INTRODUCTION

Textbook outcome (TO) is a composite outcome measure covering the surgical care process in a single outcome measure. TO has an advantage over single outcome parameters with low event rates, which have less discriminating impact to detect differences between hospitals. This study aimed to assess factors associated with TO, and evaluate hospital and network variation after case-mix correction in TO rates for liver surgery.

METHODS

This was a population-based retrospective study of all patients who underwent liver resection for malignancy in the Netherlands in 2019 and 2020. TO was defined as absence of severe postoperative complications, mortality, prolonged length of hospital stay, and readmission, and obtaining adequate resection margins. Multivariable logistic regression was used for case-mix adjustment.

RESULTS

2376 patients were included. TO was accomplished in 1380 (80%) patients with colorectal liver metastases, in 192 (76%) patients with other liver metastases, in 183 (74%) patients with hepatocellular carcinoma and 86 (51%) patients with biliary cancers. Factors associated with lower TO rates for CRLM included ASA score ≥3 (aOR 0.70, CI 0.51-0.95 p = 0.02), extrahepatic disease (aOR 0.64, CI 0.44-0.95, p = 0.02), tumour size >55 mm on preoperative imaging (aOR 0.56, CI 0.34-0.94, p = 0.02), Charlson Comorbidity Index ≥2 (aOR 0.73, CI 0.54-0.98, p = 0.04), and major liver resection (aOR 0.50, CI 0.36-0.69, p < 0.001). After case-mix correction, no significant hospital or oncological network variation was observed.

CONCLUSION

TO differs between indications for liver resection and can be used to assess between hospital and network differences.

Long-Term Outcomes of Perioperative Versus Neoadjuvant Chemotherapy for Resectable Colorectal Liver Metastases: An International Multicentre Propensity-Score Matched Analysis with Stratification by Contemporary Risk-Scoring

BACKGROUND

There is still debate regarding the principal role and ideal timing of perioperative chemotherapy (CTx) for patients with upfront resectable colorectal liver metastases (CRLM). This study assesses long-term oncological outcomes in patients receiving neoadjuvant CTx only versus those receiving neoadjuvant combined with adjuvant therapy (perioperative CTx).

METHODS

International multicentre retrospective analysis of patients with CRLM undergoing liver resection between 2010 and 2015. Characteristics and outcomes were compared before and after propensity score matching (PSM). Primary endpoints were long-term oncological outcomes, such as recurrence-free survival (RFS) and overall survival (OS). Furthermore, stratification by the tumour burden score (TBS) was applied.

RESULTS

Of 967 patients undergoing hepatectomy, 252 were analysed, with a median follow-up of 45 months. The unmatched comparison revealed a bias towards patients with neoadjuvant CTx presenting with more high-risk patients (p = 0.045) and experiencing increased postoperative complications ≥Clavien-Dindo III (20.9% vs. 8%, p = 0.003). Multivariable analysis showed that perioperative CTx was associated with significantly improved RFS (hazard ratio [HR] 0.579, 95% confidence interval [CI] 0.420-0.800, p = 0.001) and OS (HR 0.579, 95% CI 0.403-0.834, p = 0.003). After PSM (n = 180 patients), the two groups were comparable regarding baseline characteristics. The perioperative CTx group presented with a significantly prolonged RFS (HR 0.53, 95% CI 0.37-0.76, p = 0.007) and OS (HR 0.58, 95% CI 0.38-0.87, p = 0.010) in both low and high TBS patients.

CONCLUSIONS

When patients after resection of CRLM are able to tolerate additional postoperative CTx, a perioperative strategy demonstrates increased RFS and OS in comparison with neoadjuvant CTx only in both low and high-risk situations.

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.

Reevaluating the Evidence for Intensive Postoperative Extracolonic Surveillance for Nonmetastatic Colorectal Cancer

OBJECTIVES

The FACS, GILDA, and COLOFOL trials have cast doubt on the value of intensive extracolonic surveillance for resected nonmetastatic colorectal cancer and by extension metastasectomy. We reexamined this pessimistic interpretation. We evaluate an alternative explanation: insufficient power to detect a realistically sized survival benefit that may be clinically meaningful.

METHODS

A microsimulation model of postdiagnosis colorectal cancer was constructed assuming an empirically plausible efficacy for metastasectomy and thus surveillance. The model was used to predict the large-sample mortality reduction expected for each trial and the implied statistical power. A potential recurrence imbalance in the FACS trial was investigated. Goodness of fit between model predictions and trial results were evaluated. Downstream life expectancy was estimated and power calculations performed for future trials evaluating surveillance and metastasectomy.

RESULTS

For all 3 trials, the model predicted a mortality reduction of ≤5% and power of <10%. The FACS recurrence imbalance likely led to a large relative bias (>2.5) in the hazard ratio for overall survival favoring control. After adjustment, both COLOFOL and FACS results were consistent with model predictions (P>.5). A 2.6 (95% credible interval 0.5-5.1) and 3.6 (95% credible interval 0.8-7.0) month increase in life expectancy is predicted comparing intensive extracolonic surveillance-routine computed tomography scans and carcinoembryonic antigen assays-with 1 computed tomography scan at 12 months or no surveillance, respectively. An adequately sized surveillance trial is not feasible. A metastasectomy trial should randomize at least 200 to 300 patients.

CONCLUSIONS

Recent trial results do not warrant de novo skepticism of metastasectomy nor targeted extracolonic surveillance. Given the potential for clinically meaningful life-expectancy gain and significant uncertainty, a trial of metastasectomy is needed.

[Results of redo liver resections for metastatic colorectal cancer]

OBJECTIVE

To analyze patients undergoing redo liver resections for metastatic colorectal cancer.

MATERIAL AND METHODS

The study included 14 patients with colorectal cancer who underwent several redo liver resections for metastatic lesions between September 2011 and June 2021. Mean age of patients was 63.5 years. Left-sided colonic G2 adenocarcinoma T4N1-2 prevailed (wild-type KRAS).

RESULTS

Fourteen patients (100%) underwent two liver resections, 7 (50%) - three resections, 1 (7.1%) - four resections. Mean period between the first and the second liver resections was 16.2 months, between the second and the third resections - 9.9 months, between the third and the fourth resections - 5 months. Maximum follow-up period after primary surgery was 9 years and 9 months. Seventy-five percent of patients were alive after 34.2 months, 50% - after 58.9 months. N+ status of colorectal tumor decreased survival while KRAS mutation and synchronous metastatic liver lesions increased survival.

CONCLUSION

Redo liver resections for metastatic colorectal cancer are safe and ensure favorable long-term survival in certain patients.

The prognostic significance of a histological response to preoperative chemotherapy in patients with synchronous colorectal liver metastases

Objective: Preoperative chemotherapy (PC) for colorectal liver metastasis (CRLM) is widely used to improve prognosis, but its clinical benefit has not been fully established. This study aimed to assess the effectiveness of PC for synchronous CRLM and the correlation between the histological response to PC and survival. Summary of Background Data: We enrolled 69 patients who underwent initial hepatectomy for synchronous CRLM between 2004 and 2018 at Gifu University Hospital. Methods: We retrospectively analyzed the clinicopathological factors and outcomes of 69 patients who underwent hepatectomy after receiving PC (PC group: n = 43) or who underwent upfront hepatectomy (non-PC group: n = 26). In the PC group, the patients were divided into the Grade 1 (n = 27) and Grade 2/3 (n = 16) groups according to their histological responses to PC. Results: The median survival and 5-year overall survival (OS) rates were 80.9 months and 61.5%, respectively, in the PC group and 71.7 months and 61.5%, respectively, in the non-PC group ( P = 0.867). Regarding recurrence-free survival (RFS) and remnant liver-RFS, there were no significant differences between the two groups ( P = 0.087 and 0.291). However, in a subgroup analysis, the median 5-year OS, RFS, and remnant liver RFS were significantly longer in the Grade 2/3 than Grade 1 group ( P = 0.008, P = 0.002, and P &lt; 0.001, respectively). Conclusions: Some patients benefit from PC, and the histological response to PC had prognostic significance for patients with synchronous CRLM.

Neoadjuvant chemotherapy for patients with resectable colorectal cancer liver metastases: A systematic review and meta-analysis

BACKGROUND

In recent years, neoadjuvant chemotherapy (NAC) has been increasingly used in patients with resectable colorectal liver metastases. However, the efficacy and safety of NAC in the treatment of resectable colorectal liver metastases (CRLM) are still controversial.

AIM

To assess the efficacy and application value of NAC in patients with resectable CRLM.

METHODS

We searched PubMed, Embase, Web of Science, and the Cochrane Library from inception to December 2020 to collect clinical studies comparing NAC with non-NAC. Data processing and statistical analyses were performed using Stata V.15.0 and Review Manager 5.0 software.

RESULTS

In total, 32 studies involving 11236 patients were included in this analysis. We divided the patients into two groups, the NAC group (that received neoadjuvant chemotherapy) and the non-NAC group (that received no neoadjuvant chemotherapy). The meta-analysis outcome showed a statistically significant difference in the 5-year overall survival and 5-year disease-free survival between the two groups. The hazard ratio (HR) and 95% confidence interval (CI) were HR = 0.49, 95%CI: 0.39-0.61, P = 0.000 and HR = 0.48 95%CI: 0.36-0.63, P = 0.000. The duration of surgery in the NAC group was longer than that of the non-NAC group [standardized mean difference (SMD) = 0.41, 95%CI: 0.01-0.82, P = 0.044)]. The meta-analysis showed that the number of liver metastases in the NAC group was significantly higher than that in the non-NAC group (SMD = 0.73, 95%CI: 0.02-1.43, P = 0.043). The lymph node metastasis in the NAC group was significantly higher than that in the non-NAC group (SMD = 1.24, 95%CI: 1.07-1.43, P = 0.004).

CONCLUSION

We found that NAC could improve the long-term prognosis of patients with resectable CRLM. At the same time, the NAC group did not increase the risk of any adverse event compared to the non-NAC group.

Recurrence patterns and their effects on clinical outcomes after R1 resection of colorectal liver metastases: a propensity score-matched analysis

PURPOSE

The prognostic significance of the surgical margin status remains controversial for patients who undergo hepatectomy for colorectal liver metastases. This study evaluated the influence of R1 resection on recurrence patterns and prognosis in these patients.

METHODS

Between January 2001 and December 2016, 232 consecutive Japanese patients underwent initial hepatic resection for colorectal liver metastases. Their medical records were reviewed to evaluate recurrence and survival outcomes.

RESULTS

Relative to patients with R0 resection, patients with R1 resection had significantly poorer recurrence-free survival (RFS) and overall survival (OS). However, after propensity score matching, there were no significant differences in RFS and OS associated with the margin status. Nevertheless, R1 resection was associated with a significantly higher incidence of intrahepatic recurrence and early recurrence, while R0 resection was associated with a significantly higher re-resection rate for hepatic recurrence. Only eight of 55 patients with R1 resection developed recurrence at the R1 resection margin, whereas 36 patients developed recurrence at other sites/organs.

CONCLUSION

Among patients with similar characteristics, R1 resection does not affect long-term outcomes. This suggests that R1 resection itself is not a cause of a poor prognosis, but rather a potent indicator of aggressive tumor biology.

Relevance of chemotherapy and margin status in colorectal liver metastasis

PURPOSE

This retrospective, single-center study aimed to investigate the importance of chemotherapy and to come up with the optimal liver resection margin length for patients with resectable colorectal liver metastasis (CRLM).

METHODS

Patients who had undergone any form of liver resection for CRLM were reviewed and analyzed. The analyses were broken down into three parts: (1) overall effect of chemotherapy, (2) effect of chemotherapy with positive/negative resection margin, and (3) result of discriminative analysis with optimal margin length analysis.

RESULTS

In total, 381 patients were studied. Among them, 279 received chemotherapy whereas 102 did not. Survival was significantly better in patients with chemotherapy (5-year, 43.6% vs. 25.8%) (p < 0.001). Patients who received chemotherapy (n = 93) with negative margins had better survival than patients (n = 8) with positive margins (5-year, 28.1% vs. 0%) (p = 0.019). On multivariate analysis, margin involvement was the poor prognostic factor for survival. Patients who had chemotherapy (n = 238) with negative margin showed a trend of better survival than patients (n = 41) with positive margins (5-year, 45.7% vs. 29.3%) (p = 0.085). Patients (n = 93) with negative margin and no chemotherapy and patients (n = 41) with positive margin and chemotherapy had comparable survival at 5 years (p = 0.422). On multivariate analysis, tumor number was the prognostic factor for survival. By the discriminant method, 1.09 cm (sensitivity 0.242, specificity 0.718) was determined as the cut-off for optimal margin length. Patients who had margin ≥ 1.09 cm (n = 81) enjoyed significantly better survival (5-year, 54.3% vs. 33.5%) (p = 0.041). On multivariate analysis, margin length ≥ 1.09 cm was the prognostic factor for favorable survival.

CONCLUSION

The results demonstrated the important effect of perioperative chemotherapy and negative margin liver resection in management of patients suffered from CRLM.

Prospective Non-Randomized Study of Intraoperative Assessment of Surgical Resection Margin of Colo-Rectal Liver Metastases

Introduction: More than 50% of patients with colorectal cancer (CRC) develop liver metastases during the natural course of disease. Surgical resection is currently the most potentially curative method in the treatment of colorectal liver metastases (CRLM). The goal of surgery is to achieve a negative resection margin (RM) of at least 1 mm, which provides the best prognosis for patients. The RM can be assessed by the pathologist of the resected liver specimen (RLS) and by the surgeon intraoperatively. The aim of this research paper is to determine the degree of agreement on intraoperative assessment of the RM by the surgeon and histopathological RM assessment by the pathologist.

Material and methods: This prospective non-randomized double-blind study was approved by the Ethics Committee of the Oncology Institute of Vojvodina and registered on ClinicalTrials.gov #NCT04634526. The study was conducted at the Oncology Institute of Vojvodina, Sremska Kamenica, Serbia. An experienced hepatobiliary surgeon assessed RM for every specimen intra-operatively, immediately after CRLM resection. Resected CRLM lesions were analyzed by two experienced pathologists. These data were compared with pathological RM assessment as a “gold standard”. RM of 1 mm or more was rated as negative RM (RM-). Disease-free survival (DFS) and recurrence rate was calculated by RM status defined by surgeon and by pathologist.

Results: From 01 January 2015 to 31 August 2019, 98 patients were enrolled in the study. There were 219 RLS with 245 CRLM. The surgeon registered positive RM (RM+) of <1mm in 41 (18.7%) RLS. Taking the result of the histopathological assessment (HPA) as the “gold standard”, it was determined that RM was true positive in 32 (14.6%) cases. False positive RM was found in 9 (4.1%) cases. False negative RM was found in 20 (9.1%) cases. True negative RM was found in 158 (72.2%) cases. Sensitivity of surgical assessment (SA) of RM+ was 61.5% (32/52). Specificity of SA of RM+ was 94.6% (158/167). The positive predictive value (PPV) was 78.0% (32/41), while the negative predictive value (NPV) was 88.8% (158/178). The overall accuracy of the RM+ SA was 86.8% (190/219). There was no statistically significant difference in the assessment of RM+ per RLS by surgeon and pathologists (p=0.061), but it was significant when analyses per patients was performed (p=0.017). Recurrence rate for RM+ patients was 48.1% (13/27, p=0.05) for SA and 35.0% (14/40, p=0.17) for HPA. Three year DFS for RM- and RM+ was 66.5% and 27.9% (p=0.04), respectively, by SA, and 64.8% and 42.1% (p=0.106), respectively, by HPA.

Conclusion: Intraoperative assessment of RM- by surgeon of RLS is clinically meaningful. There is not a statistically significant difference in the assessment of RM+ by surgeon and pathologists per RLS, but it was statically significant on a per patient basis. RM determined by surgeon has better prognostic impact on recurrence rate and 1- and 3-year DFS than standard histopathological assessment.

The effects of resection margin and KRAS status on outcomes after resection of colorectal liver metastases

BACKGROUND

The aim of this study was to investigate the influence of resection margin status in patients with KRAS mutations (mt-KRAS) when compared to those with wild-type KRAS (wt-KRAS) on long-term outcomes in patients with resected CRLM.

METHODS

All patients who underwent resection of CRLM with curative intent between January 2011 and December 2016 and had a KRAS type recorded were included in the study. Overall survival (OS), as well as death-censored overall (RFS) and liver-specific (LS-RFS) recurrence-free survival between KRAS types and the margin status within KRAS subgroups were compared using Cox regression models.

RESULTS

Data were available for N = 500 patients (30.4% mt-KRAS). mt-KRAS status was independently associated with significantly shorter OS. Within the wt-KRAS subgroup, smaller margins were found to be associated with significantly shorter death-censored LS-RFS (p < 0.001), with HRs of 1.93 (p = 0.005) for 1-4 mm margins and 2.83 (p < 0.001) for <1 mm margins, relative to those with clear margins. No such association was observed in the mt-KRAS subgroup (p = 0.721).

CONCLUSION

The resection margin status is of greater importance in patients with wt-KRAS. Such information could be useful in the operative planning, especially for those with multiple metastatic deposits, and also in the post-operative counselling and surveillance based on the margin and KRAS status.

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

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

Size of the Largest Colorectal Liver Metastasis Is an Independent Prognostic Factor in the Neoadjuvant Setting

BACKGROUND

Up to 50% of patients diagnosed with colorectal cancer develop metastases during the course of their disease. Surgical resection remains the only curative treatment option for colorectal liver metastases (CRLM), frequently in conjunction with neoadjuvant chemotherapy. This study sought to determine if the pathologic size of the largest CRLM impacted disease-free survival (DFS) and disease-specific survival (DSS) in the setting of neoadjuvant chemotherapy.

METHODS

All patients diagnosed with CRLM who underwent neoadjuvant chemotherapy for liver resection at the Massachusetts General Hospital between 2004 and 2016 were reviewed. The median size of the largest liver lesion was used as the cutoff for grouped evaluation.

RESULTS

A total of 214 patients were included. Median follow-up was 100.0 mo (interquartile range 68.9-133.8 mo). The median size of the largest lesion was 21 mm. Patients with lesions ≥21 mm exhibited significantly worse median DFS (12.5 mo versus 16.6 mo; P = 0.033) and median DSS (71.3 mo versus 103.5 mo; P = 0.038). CRLM lesions ≥21 mm were associated with poorer DFS on univariate analysis (hazard ratio (HR) = 1.42, 95% confidence interval (CI) 1.03-1.95 P = 0.033) and multivariable analysis (HR = 1.58, 95% CI 1.07-2.35, P = 0.023). CRLM lesions ≥21 mm were also independently associated with poorer DSS after liver resection on univariate analysis (HR = 1.51, 95% CI 1.02-2.24; P = 0.037) and multivariable analysis (HR = 1.98, 95% CI: 1.27-3.07; P = 0.002).

CONCLUSIONS

The size of the largest CRLM is an important prognostic factor for both DFS and DSS after neoadjuvant therapy and serves as a useful indicator of tumor biology.

Microscopic resection margins adversely influence survival rates after surgery for colorectal liver metastases: An open ambidirectional Cohort Study

BACKGROUND

Liver resection is the most effective treatment for patients with colorectal liver metastases (CRLMs). Patients with tumour at the resection margin (R1) are reported to have worse survival compared to those with an uninvolved resection margin (R0). Recent data has questioned this finding. This study investigates whether R1 resections adversely influence survival when compared to R0 resections.

MATERIAL AND METHODS

Patients undergoing surgery for CRLM, identified from a prospectively maintained database, from January 2007 to January 2017, were included. Univariate and multivariate survival analyses were performed. p < 0.05 was significant.

RESULTS

282 patients were included. Median age 72 (32-90) years. 236 patients (83.7%) had chemotherapy and surgery, whilst 46 (16.3%) had surgery alone. 149 patients (52.8%) were alive at the end of the study period. R1 resection on univariate survival analysis was associated with better survival (HR 2.12, 95%CI 1.60-4.61, p = 0.0002). Multivariate analysis controlling for age and gender, identified presence of extrahepatic disease (HR 2.03, 95%CI 1.17-3.52, p < 0.001), R0 resection (HR 0.33, 95%CI 0.19-0.59, p = 0.003), primary tumour stage (HR 1.57, 95%CI 1.04-2.40, p = 0.034) and primary tumour differentiation (HR 2.56, 95%CI 1.01-6.46, p = 0.047), as prognostic factors for poorer survival. Five-year and 10-year survival were 54.3% and 41.7% respectively in patients with an R0 resection and, 25.8% and 17.2% in those with an R1 resection.

CONCLUSION

The presence of extrahepatic disease, an R1 resection margin, advanced T-stage and poorer tumour differentiation were associated with worse survival in CRLM surgery and R0 resection is recommended.

Colorectal liver metastases: radiopathological correlation

With the development of chemotherapy regimens, targeted therapies, and hepatic surgery, the survival of patients with colorectal liver metastases (CRLM) has dramatically improved. Imaging plays a central role for the diagnosis, staging, and treatment allocation in these patients. To interpret CRLM on imaging, radiologists must be familiar with the main imaging features of untreated tumors as well as the modifications induced by systemic therapies, and their meaning in relation to pathological tumor response and tumor biology. CRLM have the same histological features as the primary tumor. Most are “non-otherwise specified” (NOS) adenocarcinomas. The mucinous tumor is the most common of the rare subtypes. In NOS tumors, imaging usually differentiates central areas of necrosis from peripheral proliferating tumors and desmoplastic reaction. Areas of mucin mixed with fibrosis are seen in mucinous subtypes to help differentiate the metastases from other tumors cysts or hemangiomas. After treatment, the viable tumor is gradually replaced by ischemic-like necrosis and fibrosis, and remnants cells are mainly located on the periphery of tumors. Imaging can help predict the degree of tumor response, but changes can be difficult to differentiate from the pretherapeutic appearance. When chemotherapy is interrupted or in case of resistance to treatment, a peripheral infiltrating halo of tumor growth may appear. The purpose of the article is to illustrate the significance of the imaging features of colorectal liver metastases during systemic therapy, using radiopathological correlations.

Primary tumour location is an important prognostic factor in colorectal cancer liver metastases following radiofrequency ablation

AIM

To examine the outcomes and different prognoses for colorectal cancer patients with liver metastases (CRCLM) treated with radiofrequency ablation (RFA) based on the origin of the primary tumour (rectum versus colon).

MATERIALS AND METHODS

Patients diagnosed with CRCLM from July 2011 to June 2018 were assessed in the study. The study included 114 patients with 176 lesions. All of the patients underwent RFA of their CRCLM. The overall survival (OS) and progression-free survival (PFS) were assessed with Kaplan-Meier survival function estimate curves and Cox regression analysis between the group of patients with rectal cancer liver metastases (RCLM) and colon cancer liver metastases (CCLM).

RESULTS

Patients with RCLM exhibited worse OS and PFS than those with CCLM. The 1-, 2-, and 3-year OS rates were 87.5%, 75%, and 54.2% in the RCLM group and 93.9%, 87.8%, and 81.8% in the CCLM group (p=0.001), respectively. The 1-, 2-, and 3-year PFS rates were 43.7%, 22.9%, and 20.8% in the RCLM group and 57.6%, 45.4%, and 36.5% in the CCLM group (p=0.001), respectively. Multivariate analysis showed that primary tumour location, carcinoembryonic antigen (CEA), and response to pre-ablation chemotherapy were independent variables for OS and PFS. The N state of the primary tumour also had a significant impact on OS.

CONCLUSION

This study showed that patients with CCLM had better prognoses than those with RCLM following RFA treatment. If patients intend to undergo RFA for CRCLM, the location of the primary tumour should be considered in the assessment of long-term therapeutic effects.

Histopathological growth patterns and positive margins after resection of colorectal liver metastases

BACKGROUND

Histopathological growth patterns (HGPs) of colorectal liver metastases (CRLM) may be an expression of biological tumour behaviour impacting the risk of positive resection margins. The current study aimed to investigate whether the non-desmoplastic growth pattern (non-dHGP) is associated with a higher risk of positive resection margins after resection of CRLM.

METHODS

All patients treated surgically for CRLM between January 2000 and March 2015 at the Erasmus MC Cancer Institute and between January 2000 and December 2012 at the Memorial Sloan Kettering Cancer Center were considered for inclusion.

RESULTS

Of all patients (n = 1302) included for analysis, 13% (n = 170) had positive resection margins. Factors independently associated with positive resection margins were the non-dHGP (odds ratio (OR): 1.79, 95% confidence interval (CI): 1.11-2.87, p = 0.016) and a greater number of CRLM (OR: 1.15, 95% CI: 1.08-1.23 p < 0.001). Both positive resection margins (HR: 1.41, 95% CI: 1.13-1.76, p = 0.002) and non-dHGP (HR: 1.57, 95% CI: 1.26-1.95, p < 0.001) were independently associated with worse overall survival.

CONCLUSION

Patients with non-dHGP are at higher risk of positive resection margins. Despite this association, both positive resection margins and non-dHGP are independent prognostic indicators of worse overall survival.

Oncological outcome of R1 vascular margin for mass-forming cholangiocarcinoma. A single center observational cohort analysis

BACKGROUND

Recent studies validated the possibility to detach colorectal liver metastases from vessels (R1vasc) featuring R1vasc equivalent to R0 and superior to tumor exposure along the transection plane (R1par). To clarify the outcome of R1 surgery (margin <1 mm) in patients with intrahepatic cholangiocarcinoma (MFCCC), distinguishing R1par and R1vasc resections.

METHODS

Patients undergoing resection for MFCCC between 2008 and 2016 were considered. Tumor detachment from 1st/2nd-order Glissonean pedicles or hepatic veins was performed in advanced diseases. R0, R1par, and R1vasc were compared.

RESULTS

The study included 84 resection areas in 59 patients (17 R1vasc). R1vasc group had local recurrence risk similar to R1par group (per-patient analysis 29% vs. 36%; per-resection area analysis 29% vs. 32%), higher than R0 group (3% and 2%, p = 0.003 and p = 0.0003). R1vasc and R1par groups had similar overall and recurrence-free survival (median OS 30 vs. 30 months; RFS 10 vs. 8 months), lower than R0 group (70 and 39 months, p = 0.066 and p = 0.007).

CONCLUSION

In MFCCC patients, R1vasc resection is not an adequate treatment. Local disease control and survival after R1vasc resection are lower than after R0 resection and similar to R1par resection. R1vasc resection could be exclusively considered to achieve resectability in otherwise unresectable patients.

Impact of resection margins for colorectal liver metastases in laparoscopic and open liver resection: a propensity score analysis

BACKGROUND

There is no clear consensus over the optimal width of resection margin for colorectal liver metastases (CRLM), with evolving definitions alongside the advances on the management of the disease. In addition, data on the impact of resection margin after laparoscopic liver resection are still scarce.

METHODS

Prospectively maintained databases of patients undergoing open or laparoscopic CRLM resection in 7 European tertiary hepatobiliary referral centres were reviewed. After propensity score matching (PSM), the influence of 1 mm and wider margins on OS and DFS were evaluated in open and laparoscopic cohorts.

RESULTS

After PSM, 648 patients were comparable in each group. The incidence of positive margins (< 1 mm) was similar in open and laparoscopic groups (17% vs 13%, p = 0,142). Margins < 1 mm were associated with shorter RFS in open (12 vs 26 months, p = 0.042) and in laparoscopic group (13 vs 23, p = 0,002). Margins < 1 mm were associated with shorter OS in open (36 vs 57 months, p = 0.027), but not in laparoscopic group (49 vs 60, p = 0,177). Subgroups with margins ≥ 1 mm (1-4 mm, 5-9 mm, ≥ 10 mm) presented similar RFS in open (p = 0,251) or laparoscopic cohorts (p = 0.117), as well as similar OS in open (p = 0.295) or laparoscopic cohorts (p = 0.908). In the presence of liver recurrence, repeat liver resection was performed in 70 (30%) patients in the open group and 88 (48%) in the laparoscopic group (p < 0.001).

CONCLUSIONS

Our study suggests that a positive resection margin (less than 1 mm) width does not impact OS after laparoscopic resection of CRLMs as it does in open liver resection. However, a positive margin continues to affect RFS in open and laparoscopic resection. Wider margins than 1 mm do not seem to improve oncological results in open or laparoscopic surgery.

Shanghai international consensus on diagnosis and comprehensive treatment of colorectal liver metastases (version 2019)

The liver is the most common anatomical site for hematogenous metastases from colorectal cancer. Therefore effective treatment of liver metastases is one of the most challenging elements in the management of colorectal cancer. However, there is rare available clinical consensus or guideline only focusing on colorectal liver metastases. After six rounds of discussion by 195 clinical experts of the Shanghai International Consensus Expert Group on Colorectal Liver Metastases (SINCE) from 29 countries or regions, the Shanghai Consensus has been finally completed, based on current research and expert experience. The consensus emphasized the principle of multidisciplinary team, provided detailed diagnosis approaches, and guided precise local and systemic treatments. This Shanghai Consensus might be of great significance to standardized diagnosis and treatment of colorectal liver metastases all over the world.

Does KRAS mutation status impact the risk of local recurrence after R1 vascular resection for colorectal liver metastasis? An observational cohort study

INTRODUCTION

R0 margin is the standard in the surgical treatment of colorectal liver metastases (CLM). Recently R1 surgery, at least that enabling CLM vessel-detachment (R1vasc), seems comparable to R0. As a possible background of that biologic factors could play some role. Among them, KRAS has been investigated in the present study.

METHODS

Patients who underwent curative surgery for CLM between 2008 and 2016 were identified. R0, R1vasc and parenchymal R1 (R1par; tumor exposure once dissected from the parenchyma) resections with known KRAS status were analyzed.

RESULTS

Of 1000 resection areas in 340 patients, 654 (65%) R0, 98 (10%) R1vasc and 248 (25%) R1par. In mutated KRAS (mKRAS), local recurrence (LR) was similar between R0 and R1vasc (per-patient 4,8% vs. 2%, p = 0.628; per-area 2,1% vs. 1,9%, p = 0.940), while higher in R1par (per-patient 25,4% and per-area 19,5%; p < 0.001 for both). In wild-type KRAS (wtKRAS), R0 had less LR compared to R1vasc (per-patient 7,6% vs 14,6%, p = 0.335; per-area 3,1% vs 13,3%, p = 0.012) and R1par (per-patient 18,3%, p = 0.060; per-area 9,9%, p = 0.013). KRAS did not impact LR in R0 (per-patient 7,6% vs. 4,8%, p = 0.491; per-area 3,1% vs. 2,1%, p = 0.555), while wtKRAS R1par had less LR compared to mKRAS R1par (per-patient 18,3% vs 25,4%, p = 0.404; per-area 9,9% vs 19,5%, p = 0.048). Inversely, LR was increased in wtKRAS R1vasc compared to mKRAS R1vasc (per-patient 14,6% vs 2%, p = 0.043; per-area 13,3% vs 1,9%, p = 0.046).

CONCLUSION

KRAS status does not impact LR risk in R0 resection. Inversely, R1vasc vs R1par LR risk is reduced in mKRAS, and increased in wtKRAS. If confirmed these results are of note.

Hepatic resection after neoadjuvant chemotherapy for patients with liver metastases from colorectal cancer: need for cautious planning

Purpose

Current neoadjuvant chemotherapy (NAC) may enable therapies such as surgical resection and local ablation of metastases in patients with colorectal liver metastasis (CLM). We evaluated outcomes in CLM patients who underwent resection and/or local treatment after NAC and identified prognostic factors for oncologic outcomes.

Methods

Patients who received NAC followed by resection and/or local treatment of hepatic metastasis from 2013 to 2015 were included. Treatment and tumor-related variables were tabulated. Recurrence-free survival (RFS) and overall survival (OS) were analyzed using the Kaplan-Meier method. Cox regression analysis was used to identify factors associated with RFS and OS.

Results

Sixty-eight patients received NAC followed by resection and/or local treatment of hepatic metastases. Targeted therapy was administered in 50% of the patients. RFS was 35.8% at 1 year and 19.4% at 2 years postoperatively. OS was 95.6% at 1 year and 88.2% at 2 years postoperatively. In the multivariable analysis, R1 resection margin (hazard ratio [HR], 3.95; P = 0.008) of the liver metastases and ypN1/ypN2 (HR, 2.356 and 1.983, respectively; P = 0.041) were associated with poor RFS. Both factors were also significantly related to OS.

Conclusion

Resection margin of the metastatic tumor and ypN status are the only relevant factors for RFS and OS in CLM patients treated with NAC. Despite early and high rates of recurrence, CLM patients treated with NAC who undergo resection and/or local treatment have acceptable OS. Multidisciplinary review of candidates for surgery and cautious planning are crucial for achieving optimal outcomes.

Recent advances in liver transplantation for cancer: The future of transplant oncology

Liver transplantation is widely indicated as a curative treatment for selected patients with hepatocellular carcinoma. However, with recent therapeutic advances, as well as efforts to increase the donor pool, liver transplantation has been carefully expanded to patients with other primary or secondary malignancies in the liver. Cholangiocarcinoma, colorectal and neuroendocrine liver metastases, and hepatic epithelioid haemangioendothelioma are amongst the most relevant new indications. In this review we discuss the fundamental concepts of this ambitious undertaking, as well as the newest indications for liver transplantation, with a special focus on future perspectives within the recently established concept of transplant oncology.

Preoperative Chemotherapy and Resection Margin Status in Colorectal Liver Metastasis Patients: A Propensity Score–Matched Analysis

In this article, we compared the early and long-term outcomes of patients with metastatic colorectal cancer treated with chemotherapy followed by resection with those of patients undergoing surgery first, focusing our analysis on resection margin status. Patients who underwent liver resection with curative intent for colorectal liver metastases from July 2001 to January 2018 were included in the analysis. Propensity score matching was used to reduce treatment allocation bias. The cohort comprised 164 patients; 117 (71.3%) underwent liver resection first, whereas the remaining 47 (28.7%) had preoperative chemotherapy. After a 1:1 ratio of propensity score matching, 47 patients per group were evaluated. A positive resection margin was found in 13 patients in the surgery-first group (25.5%) versus 4 (8.5%) in the preoperative chemotherapy group ( P = 0.029). Postmatched logistic regression analysis showed that only preoperative chemotherapy was significantly associated with the rate of positive resection margin (odds ratio 0.24, 95% confidence interval 0.07–0.81; P = 0.022). Median follow-up was 41 months (interquartile range 8–69). Cox proportional hazard regression analysis revealed that only positive resection margin was a significant negative prognostic factor (hazard ratio 2.2, 95% CI 1.18–4.11; P = 0.014). Within the preoperative chemotherapy group, median overall survival was 40 months in R0 patients and 10 months in R1 patients ( P = 0.016). Although preoperative chemotherapy in colorectal liver metastasis patients may affect the rate of positive resection margin, its impact on survival seems to be limited. In the present study, the most important prognostic factor was the resection margin status.

Sub-millimeter surgical margin is acceptable in patients with good tumor biology after liver resection for colorectal liver metastases

BACKGROUND

The definition of R1 resection in colorectal cancer liver metastases (CRLM) remains debatable. This retrospective study was conducted to clarify the impact of R1 margin on patient survival after liver resection for CRLM, taking into consideration tumor biology, including RAS status and chemotherapy response.

METHODS

We retrospectively analysed the clinical and survival data of 214 CRLM patients with initially resectable liver metastases who underwent liver resection after receiving neoadjuvant chemotherapy between January 2006 and December 2016.

RESULTS

R1 resection significantly impacted patients' overall survival (OS) and disease-free survival (DFS) in the overall patient cohort (5-year OS: 53.2% for R0 vs 38.2% for R1, P = 0.001; 5-year DFS: 26.5% for R0 vs 10.5% for R1, P = 0.002). In the RAS wild-type subgroup and respond to chemotherapy (RC) subgroup, R1 reached a similar OS to those who underwent R0 resection (RAS wild-type, P = 0.223; RC, P = 0.088). For the RAS mutated subgroup and no response to chemotherapy (NRC) subgroup, OS was significantly worse underwent R1 resection (RAS mutant, P = 0.002; NRC, P = 0.022). When considering tumor biology combining RAS and chemotherapy response status, R1 resection was only acceptable in patients with both RAS wild-type and RC (5-year OS: 66.4% for R0 vs 65.2% for R1, p = 0.884), but was significantly worse in those with either RAS mutation or NRC.

CONCLUSIONS

Tumor biology plays an important role in deciding the appropriate resection margin in patients with CRLM undergoing radical surgery. R1 resection margin is only acceptable in RAS wild-type patients who respond to chemotherapy.

The impact of R1 resection for colorectal liver metastases on local recurrence and overall survival in the era of modern chemotherapy: An analysis of 1,428 resection areas

BACKGROUND

It is still unclear whether a positive surgical margin after resection of colorectal liver metastases remains a poor prognostic factor in the era of modern perioperative chemotherapy. The aim of this study was to evaluate whether preoperative chemotherapy has an impact on reducing local recurrence after R1 resection, and the impact of local recurrence on overall survival.

METHODS

Between 2000 and 2014, a total of 421 patients underwent resection for colorectal liver metastases at our unit after preoperative chemotherapy. The overall number of analyzed resection areas was 1,428.

RESULTS

The local recurrence rate was 12.8%, significantly higher after R1 resection than after R0 (24.5% vs 8.7%; P < .001). These results were also confirmed in patients with response to preoperative chemotherapy (23.1% after R1 vs 11.2% after R0; P < .001). At multivariate analysis, R1 resection was the only independent risk factor for local recurrence (P < .001). At the analysis of the 1,428 resection areas, local recurrence significantly decreased according to the increase of the surgical margin width (from 19.1% in 0 mm margin to 2.4% in ≥10 mm). At multivariable logistic regression analysis for overall survival, the presence of local recurrence showed a significant negative impact on 5-year overall survival (P < .001).

CONCLUSION

Surgical margin recurrence after modern preoperative chemotherapy for colorectal liver metastases was still significantly higher after R1 resection than it was after R0 resection. Local recurrence showed a negative prognostic impact on overall survival. R0 resection should be recommended whenever technically achievable, as well as in patients treated by modern preoperative chemotherapy.

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

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

R1 Resection for Colorectal Liver Metastases: a Survey Questioning Surgeons about Its Incidence, Clinical Impact, and Management

BACKGROUND

A ≥ 1-mm margin is standard for resection of colorectal liver metastases (CLM). However, R1 resection is not rare (10-30%), and chemotherapy could mitigate its impact. The possibility of detaching CLM from vessels (R1 vascular margin) has been described. A reappraisal of R1 resection is needed.

METHODS

A 19-question survey regarding R1 resection for CLM was sent to hepatobiliary surgeons worldwide. Seven clinical cases were included.

RESULTS

In total, 276 surgeons from 52 countries completed the survey. Ninety percent reported a negative impact of R1 resection (74% local recurrence, 31% hepatic recurrence, and 36% survival), but 50% considered it sometimes required for resectability. Ninety-one percent of responders suggested that the impact of R1 resection is modulated by the response to chemotherapy and/or CLM characteristics. Half considered the risk of R1 resection to be an indication for preoperative chemotherapy in patients who otherwise underwent upfront resection, and 40% modified the chemotherapy regimen when the tumor response did not guarantee R0 resection. Nevertheless, 80% scheduled R1 resection for multiple bilobar CLM that responded to chemotherapy. Forty-five percent considered the vascular margin equivalent to R0 resection. However, for lesions in contact with the right hepatic vein, right hepatectomy remained the standard. Detachment from the vein was rarely considered (10%), but 27% considered detachment in the presence of multiple bilobar CLM.

CONCLUSIONS

A negative margin is still standard for CLM, but R1 resection is no longer just a technical error. R1 resection should be part of the modern multidisciplinary, aggressive approach to CLM.

Transplantation for colorectal metastases: on the edge of a revolution

Liver transplantation (LT) has become the standard of care for selected primary and secondary malignancies. Considered a contra-indication to transplantation until recently, unresectable colorectal liver metastases (CRLM) have gained interest since the publication of the SECA trial by the University of Oslo. It showed a 5-year overall survival of 60%, comparable to the one of standard transplant indication. This report generated multiple questions about the place of LT for CRLM and gave raise to several trials aiming at answering them. The present review is exploring this topic, defining the current state of the field, and extrapolating the future milestones.