Performance of prognostic scores in predicting long-term outcome following resection of colorectal liver metastases

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.

Current landscape of preoperative neoadjuvant therapies for initial resectable colorectal cancer liver metastasis

Colorectal cancer liver metastasis (CRLM) presents a clinical challenge, and optimizing treatment strategies is crucial for improving patient outcomes. Surgical resection, a key element in achieving prolonged survival, is often linked to a heightened risk of recurrence. Acknowledging the potential benefits of preoperative neoadjuvant chemotherapy in managing resectable liver metastases, this approach has gained attention for its role in tumor downsizing, assessing biological behavior, and reducing the risk of postoperative recurrence. However, the use of neoadjuvant chemotherapy in initially resectable CRLM sparks ongoing debates. The balance between tumor reduction and the risk of hepatic injury, coupled with concerns about delaying surgery, necessitates a nuanced approach. This article explores recent research insights and draws upon the practical experiences at our center to address critical issues regarding considerations for initially resectable cases. Examining the criteria for patient selection and the judicious choice of neoadjuvant regimens are pivotal areas of discussion. Striking the right balance between maximizing treatment efficacy and minimizing adverse effects is imperative. The dynamic landscape of precision medicine is also reflected in the evolving role of gene testing, such as RAS/BRAF and PIK3CA, in tailoring neoadjuvant regimens. Furthermore, the review emphasizes the need for a multidisciplinary approach to navigate the complexities of CRLM. Integrating technical expertise and biological insights is crucial in refining neoadjuvant strategies. The management of progression following neoadjuvant chemotherapy requires a tailored approach, acknowledging the diverse biological behaviors that may emerge. In conclusion, this review aims to provide a comprehensive perspective on the considerations, challenges, and advancements in the use of neoadjuvant chemotherapy for initially resectable CRLM. By combining evidence-based insights with practical experiences, we aspire to contribute to the ongoing discourse on refining treatment paradigms for improved outcomes in patients with CRLM.

Local interventions for colorectal cancer metastases to liver and lung

BACKGROUND

Colorectal cancer is a common cause of cancer-related deaths. About 1/3 of all cases present with distant metastasis, with the liver as the leading site and the lung as the most common extra-abdominal site.

AIMS

It was aimed to evaluate the clinical characteristics and the outcomes of colorectal cancer patients with liver or lung metastasis who had received local treatments.

METHODS

This is a retrospective, cross-sectional, and descriptive study. The study was performed with colorectal cancer patients that referred to the medical oncology clinic of a university hospital between December 2013 and August 2021.

RESULTS

A total number of 122 patients who have received local treatments were included. Radiofrequency ablation was applied in 32 patients (26.2%), metastasis was surgically resected in 84 patients (68.9%), and stereotactic body radiotherapy was preferred in six patients (4.9%). At the first follow-up control after completion of local or multimodal treatment, no residual tumor was determined with radiological assessment in 88 patients (72.1%). The median progression-free survival (16.7 months vs 9.7 months) (p = .000) and the median overall survival (37.3 months vs 25.5 months) (p = .004) of these patients were significantly better than the patients with residual disease.

CONCLUSIONS

Local interventions that are applied to highly selected patients may improve the survival of metastatic colorectal cancer patients. A close follow-up after local therapies is important to diagnose recurrent disease because repeated local interventions may be possible to achieve better outcomes.

Randomised, placebo-controlled, phase 3 trial of the effect of the omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) on colorectal cancer recurrence and survival after surgery for resectable liver metastases: EPA for Metastasis Trial 2 (EMT2) study protocol

INTRODUCTION

There remains an unmet need for safe and cost-effective adjunctive treatment of advanced colorectal cancer (CRC). The omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) is safe, well-tolerated and has anti-inflammatory as well as antineoplastic properties. A phase 2 randomised trial of preoperative EPA free fatty acid 2 g daily in patients undergoing surgery for CRC liver metastasis showed no difference in the primary endpoint (histological tumour proliferation index) compared with placebo. However, the trial demonstrated possible benefit for the prespecified exploratory endpoint of postoperative disease-free survival. Therefore, we tested the hypothesis that EPA treatment, started before liver resection surgery (and continued postoperatively), improves CRC outcomes in patients with CRC liver metastasis.

METHODS AND ANALYSIS

The EPA for Metastasis Trial 2 trial is a randomised, double-blind, placebo-controlled, phase 3 trial of 4 g EPA ethyl ester (icosapent ethyl (IPE; Vascepa)) daily in patients undergoing liver resection surgery for CRC liver metastasis with curative intent. Trial treatment continues for a minimum of 2 years and maximum of 4 years, with 6 monthly assessments, including quality of life outcomes, as well as annual clinical record review after the trial intervention. The primary endpoint is CRC progression-free survival. Key secondary endpoints are overall survival, as well as the safety and tolerability of IPE. A minimum 388 participants are estimated to provide 247 CRC progression events during minimum 2-year follow-up, allowing detection of an HR of 0.7 in favour of IPE, with a power of 80% at the 5% (two sided) level of significance, assuming drop-out of 15%.

ETHICS AND DISSEMINATION

Ethical and health research authority approval was obtained in January 2018. All data will be collected by 2025. Full trial results will be published in 2026. Secondary analyses of health economic data, biomarker studies and other translational work will be published subsequently.

TRIAL REGISTRATION NUMBER

NCT03428477.

Microsatellite instability is associated with worse overall survival in resectable colorectal liver metastases

BACKGROUND

Microsatellite instability (MSI) has been associated with improved overall survival (OS) in locoregional colorectal cancer; however, the effects on colorectal liver metastases (CRLM) have not been studied.

METHODS

The National Cancer Database (NCDB) was queried for patients with CRLM that underwent metastasectomy. Patients with microsatellite stable tumors (MSS) (n = 2,316, 84.4%) were compared those with MSI (n = 427, 15.6%).

RESULTS

Baseline characteristics, including sex, race, and underlying comorbidities, were similar between groups. MSS patients had lower rates of high-risk pathologic features and higher rates of receiving multi-agent chemotherapy. On Kaplan-Meier analysis, median OS in the MSS group was improved compared with the MSI group (41.1 mo vs. 33.2 mo, p < 0.01). On multivariate analysis MSI status remained associated with worse OS (HR: 1.21 95% CI: 1.01-1.46, p = 0.04).

CONCLUSIONS

This national analysis of CRLM validates MSI status as a biomarker to guide clinical decision-making due to the associated poor prognosis.

Prediction of survival in patients with colorectal liver metastases- development and validation of a prognostic score model

BACKGROUND

Metastatic spread of colorectal cancer to the liver impacts prognosis. Advances in chemotherapy have resulted in increased resectability rates and thereby improved survival in patients with colorectal liver metastases (CRLM). However, criteria are needed to ensure that patients selected for hepatic resection benefit from the invasive therapy. The study aimed to construct a predictive model for overall survival (OS) in patients with CRLM, based on preoperatively available information.

METHODS

The retrospective cohort study reviewed all patients with CRLM discussed at multidisciplinary team conference at Karolinska University Hospital, Stockholm, Sweden, 2013-2018. Independent prognostic factors for OS were identified, based on which a score model was generated. The model was validated on patients treated for CRLM at Hôpital Universitaire Paul Brousse, Villejuif, France, 2007-2018. Calibration and discrimination methods were used for internal and external validation.

RESULTS

The Swedish development cohort included 1013 patients, the French validation cohort 391 patients. Poor OS was significantly associated with age>60years (hazard ratio (HR) 3.57 (95%CI 2.18-9.94)), number of CRLM (HR 4.59 (2.83-12.20)), diameter of largest CRLM>5 cm (HR 2.59 (1.74-5.03)), right-sided primary tumour (HR 2.98 (2.00-5.80)), extrahepatic disease (HR 4.14 (2.38-15.87)) and non-resectability (HR 0.77 (0.66-0.90)). The C-statistic for prediction of OS was .74, in the development cohort and 0.69 in the validation cohort.

CONCLUSION

The presented predictive score model can adequately predict OS for patients at the initial diagnosis of CRLM. The prognostic model could be of clinical value in the management of all patients with CRLM, by predicting individualized survival and thereby facilitating treatment recommendations.

Survival after liver resection and liver transplantation for colorectal liver metastases: a comparative analysis stratified by metabolic tumor volume assessed by 18F-FDG PET/CT

BACKGROUND

Many patients undergoing resection for colorectal liver metastases (CRLM) recur with poor survival. Overall survival (OS) following liver transplantation (LT) for CRLM is reported to be about 80% at 5 years. In this study, survival following resection versus transplantation for CRLM in patients with moderate (6-70 cm³) metabolic tumor volume (MTV) from the preoperative positron emission tomography (PET) was compared.

METHODS

Disease-free survival (DFS), OS and post recurrence survival (PRS) following resection (n = 18) and LT (n = 12) was compared by using the Kaplan Meier method and log rank test for patients with moderate MTV.

RESULTS

Patients undergoing LT had unresectable metastases, significantly lower age, higher tumor burden score and number of liver metastases, longer time from diagnosis to surgery, and more patients received neoadjuvant chemotherapy. OS at 5 years was 39% in the resection group and 83% in the LT group (P = 0.012). PRS was significantly improved in patients treated with LT compared to resection with 71% alive at 5 years from recurrence compared to 17% in the resection group (P = 0.017).

CONCLUSION

LT for selected patients seems to be superior to resection as treatment for CRLM for patients with moderate MTV.

Predicting 10-year survival after resection of colorectal liver metastases; an international study including biomarkers and perioperative treatment

BACKGROUND

The aim of this study was to develop a prediction model for 10-year overall survival (OS) after resection of colorectal liver metastasis (CRLM) based on patient, tumour and treatment characteristics.

METHODS

Consecutive patients after complete resection of CRLM were included from two centres (1992-2019). A prediction model providing 10-year OS probabilities was developed using Cox regression analysis, including KRAS, BRAF and histopathological growth patterns. Discrimination and calibration were assessed using cross-validation. A web-based calculator was built to predict individual 10-year OS probabilities.

RESULTS

A total of 4112 patients were included. The estimated 10-year OS was 30% (95% CI 29-32). Fifteen patient, tumour and treatment characteristics were independent prognostic factors for 10-year OS; age, gender, location and nodal status of the primary tumour, disease-free interval, number and diameter of CRLM, preoperative CEA, resection margin, extrahepatic disease, KRAS and BRAF mutation status, histopathological growth patterns, perioperative systemic chemotherapy and hepatic arterial infusion pump chemotherapy. The discrimination at 10-years was 0.73 for both centres. A simplified risk score identified four risk groups with a 10-year OS of 57%, 38%, 24%, and 12%.

CONCLUSIONS

Ten-year OS after resection of CRLM is best predicted with a model including 15 patient, tumour, and treatment characteristics. The web-based calculator can be used to inform patients. This model serves as a benchmark to determine the prognostic value of novel biomarkers.

Low skeletal muscle mass and post-operative complications after surgery for liver malignancies: a meta-analysis

Purpose

To assess the influence of low skeletal muscle mass (LSMM) on post-operative complications in patients with hepatic malignancies grade (Clavien Dindo ≥ 3) undergoing resection.

Methods

MEDLINE, Cochrane, and SCOPUS databases were screened for associations between sarcopenia and major post-operative complications (≥ grade 3 according to Clavien-Dindo classification) after resection of different malignant liver tumors. RevMan 5.3 software was used to perform the meta-analysis. The methodological quality of the included studies was assessed according to the QUIPS instrument.

Results

The analysis included 17 studies comprising 3157 patients. Subgroup analyses were performed for cholangiocarcinoma (CCC), colorectal cancer (CRC) liver metastases, and hepatocellular carcinoma (HCC). LSMM as identified on CT was present in 1260 patients (39.9%). Analysis of the overall sample showed that LSMM was associated with higher post-operative complications grade Clavien Dindo ≥ 3 (OR 1.56, 95% CI 1.25–1.95, p < 0.001). In the subgroup analysis, LSMM was associated with post-operative complications in CRC metastases (OR 1.60, 95% CI 1.11–2.32, p = 0.01). In HCC and CCC sub-analyses, LSMM was not associated with post-operative complications in simple regression analysis.

Conclusion

LSMM is associated with major post-operative complications in patients undergoing surgery for hepatic metastases and it does not influence major post-operative complications in patients with HCC and CCC.

Machine Learning Approach to Stratifying Prognosis Relative to Tumor Burden after Resection of Colorectal Liver Metastases: An International Cohort Analysis

BACKGROUND

Assessing overall tumor burden on the basis of tumor number and size may assist in prognostic stratification of patients after resection of colorectal liver metastases (CRLM). We sought to define the prognostic accuracy of tumor burden by using machine learning (ML) algorithms compared with other commonly used prognostic scoring systems.

STUDY DESIGN

Patients who underwent hepatectomy for CRLM between 2001 and 2018 were identified from a multi-institutional database and split into training and validation cohorts. ML was used to define tumor burden (ML-TB) based on CRLM tumor number and size thresholds associated with 5-year overall survival. Prognostic ability of ML-TB was compared with the Fong and Genetic and Morphological Evaluation scores using Cohen's d.

RESULTS

Among 1,344 patients who underwent resection of CRLM, median tumor number (2, interquartile range 1 to 3) and size (3 cm, interquartile range 2.0 to 5.0) were comparable in the training (n = 672) vs validation (n = 672) cohorts; patient age (training 60.8 vs validation 61.0) and preoperative CEA (training 10.2 ng/mL vs validation 8.3 ng/mL) was also similar (p > 0.05). ML empirically derived optimal cutoff thresholds for number of lesions (3) and size of the largest lesion (1.3 cm) in the training cohort, which were then used to categorize patients in the validation cohort into 3 prognostic groups. Patients with low, average, or high ML-TB had markedly different 5-year overall survival (51.6%, 40.9%, and 23.1%, respectively; p < 0.001). ML-TB was more effective at stratifying patients relative to 5-year overall survival (low vs high ML-TB, d = 2.73) vs the Fong clinical (d = 1.61) or Genetic and Morphological Evaluation (d = 0.84) scores.

CONCLUSIONS

Using a large international cohort, ML was able to stratify patients into 3 distinct prognostic categories based on overall tumor burden. ML-TB was noted to be superior to other CRLM prognostic scoring systems.

Anaesthesia for Hepatic Resection Surgery

This article will focus on the perioperative management of hepatic resection for colorectal cancer (CRC) liver metastases (CLRMs) (the liver is the dominant metastatic site for CRC) within the context of the Enhanced Recovery After Surgery (ERAS) paradigm. It discusses the epidemiology and outcomes along with the history of hepatic resection surgery and pertinent anatomy. The discussion of the preoperative phase includes patient selection, assessment of liver functional status, and new developments in prehabilitation. The intraoperative phase details developments in surgical and anesthetic techniques to minimize liver hemorrhage and reduce the risk of postoperative hepatic failure. Newer analgesic options are included. Management of potential complications is outlined in the postoperative section followed by a description of current evidence for ERAS and future directions.

Nontumor related risk score: A new tool to improve prediction of prognosis after hepatectomy for colorectal liver metastases

BACKGROUND

Prognostic stratification of patients with colorectal cancer liver metastasis based solely on tumor-related factors has only moderate discriminatory ability. We hypothesized that the inclusion of nontumor related factors can improve prediction of long-term prognosis of patients with colorectal cancer liver metastasis.

METHODS

Nontumor related laboratory markers were assessed utilizing a training cohort from 2 U.S. institutions (n = 1,205). Factors independently associated with prognosis were used to develop a nontumor related prognostic score. The discriminatory ability, assessed by Harrell's C-statistics (C-index) and net reclassification improvement, was validated and compared with 3 commonly used tumor-related clinical risk scores: Fong clinical risk scores, m-clinical risk scores, and Genetic and Morphological Evaluation (GAME) score in an external validation cohort from 5 Asian (n = 1,307) and 3 European (n = 1,058) institutions. The discriminatory ability of nontumor related prognostic score combined with each of these 3 tumor-related prognostic scores was also estimated.

RESULTS

Alkaline phosphatase (hazard ratio 1.43; 95% confidence interval, 1.11-1.84), albumin (hazard ratio 0.71; 95% confidence interval, 0.57-0.89), and mean corpuscular volume (hazard ratio 19.0, per log unit; 95% confidence interval, 4.79-75.0) were each independently associated with increased risk of death after resection of colorectal cancer liver metastasis (all P < .05). In turn, alkaline phosphatase, albumin, and mean corpuscular volume were combined to form a nontumor related prognostic score (2.942 × mean corpuscular volume + 0.399 × alkaline phosphatase-0.339 × albumin-12) × 10 (median, 16; range, 1-30). The nontumor related prognostic score had good-to-modest discriminatory ability in the external cohort (C-index = 0.58), which was comparable to the 3 established tumor-related prognostic scores (C-index: Fong clinical risk scores, 0.53, m-clinical risk scores, 0.55, GAME, 0.58). The addition of the nontumor related prognostic score to the tumor-related prognostic scores enhanced the discriminatory ability in the entire study cohort (C-index: nontumor related score+Fong, 0.60, nontumor related score+m-clinical risk scores, 0.61, nontumor related score+GAME, 0.64), as well reclassification improvement (42.5, 42.7%, and 21.2%, respectively).

CONCLUSION

Nontumor related prognostic information may help improve the prognostic stratification of patients after resection of colorectal cancer liver metastasis. The nontumor related prognostic score may be combined with tumor-related prognostic tools to enhance prognostic stratification of patients with colorectal cancer liver metastasis.

Which surgical strategy for colorectal cancer with synchronous hepatic metastases provides the best outcome? A comparison between primary first, liver first and simultaneous approach

BACKGROUND

There is no clear consensus about the best surgical strategy for patients with colorectal cancer (CRC) and synchronous liver metastases (SCRLM).

METHODS

Between 2009 and 2019, patients with CRC and SCRLM considered for curative treatment were included. Perioperative and follow-up data were analysed to examine the safety and survival outcomes of primary first (PF), liver first (LF) and simultaneous resection (SR) strategies.

RESULTS

204 patients were identified, consisting of PF (n = 129), LF (n = 26) and SR (n = 49). Forty-five patients (22.1%) failed to have either the primary or the liver metastases resected following initial LF (n = 11, 42.3%) or PF (n = 34, 26.4%), respectively (p < 0.001). The postoperative morbidity rates were 31.0%, 38.4% and 40.8% in PF, LF and SR group, respectively (p = 0.409); the mortality rates were 2.3%, 0% and 4.1%, respectively (p = 0.547). The 1-, 3- and 5-year overall survival (OS) were 94%, 72%, 53% in the PF group, 74%, 54%, 36% in the LF group, and 91%, 74%, 63% in the SR group. LF group had the worst OS compared to PF and SR (p = 0.040, p = 0.052). The 1-, 3- and 5-year disease-free survival (DFS) were 31%, 15%, 10% in PF, 21%, 9% and 9% in LF and 45%, 28% and 28% in SR group, respectively. SR group had a better DFS compared to PF and LF (p = 0.005, p = 0.008). At the multivariate analysis, there was no difference between the three strategies in terms of OS (PF vs SR OS-HR 1.090, p = 0.808; LF vs SR OS-HR 1.582, p = 0.365) and the PF had a worse DFS compared to the SR approach (PF vs SR DFS-HR 1.803, p = 0.007; LF vs SR DFS-HR 1.252, p = 0.492).

CONCLUSIONS

PF, LF and SR had comparable postoperative morbidity and mortality. The three surgical strategies had similar OS outcomes. The PF strategy was associated with a worse DFS than SR, while the LF approach was associated with a high failure rate to progress to the second stage (primary tumour resection).

Sarcopenia and long-term survival outcomes after local therapy for colorectal liver metastasis: a meta-analysis

BACKGROUND

Sarcopenia is defined as either low pre-operative muscle mass or low muscle density on abdominal CT imaging. It has been associated with worse short-term outcomes after surgery for colorectal liver metastases. This study aimed to evaluate whether sarcopenia also impacts long-term survival outcomes in these patients.

METHODS

A random-effects meta-analysis was conducted following the PRISMA guidelines. Overall survival (OS) and disease-free survival (DFS) outcomes were evaluated.

RESULTS

Eleven studies were included, ten reporting on the impact of low muscle mass and four on low muscle density. Sample sizes ranged between 47 and 539 (2124 patients in total). Altogether, 897 (42%) patients were considered sarcopenic, although definitions varied between studies. Median follow-up was 21-74 months. Low muscle mass (hazard ration (HR) 1.35, 95%CI 1.08-1.68) and low muscle density (HR 1.97, 95%CI 1.07-3.62) were associated with impaired OS. Low muscle mass (pooled HR 1.17, 95%CI 0.94-1.46) and low muscle density (pooled HR 1.13, 95%CI 0.85-1.50) were not associated with impaired RFS.

DISCUSSION

Sarcopenia is associated with poorer OS, but not RFS, in patients with CRLM. Additional studies with standardized sarcopenia definitions are needed to better assess the impact of sarcopenia in patients with CRLM.

The prognostic value of preoperative serum lactate dehydrogenase levels in patients underwent curative-intent hepatectomy for colorectal liver metastases: A two-center cohort study

Background

The prognostic value of lactate dehydrogenase (LDH) in colorectal cancer patients has remained inconsistent between nonmetastatic and metastatic settings. So far, very few studies have included LDH in the prognostic analysis of curative‐intent surgery for colorectal liver metastases (CRLM).

Patients and Methods

Five hundred and eighty consecutive metastatic colorectal cancer patients who underwent curative‐intent CRLM resection from Sun Yat‐sen University Cancer Center (434 patients) and Sun Yat‐sen University Sixth Affiliated Hospital (146 patients) in 2000–2019 were retrospectively collected. Overall survival (OS) was the primary end point. Cox regression model was performed to identify the prognostic values of preoperative serum LDH levels and other clinicopathology variables. A modification of the established Fong CRS scoring system comprising LDH was developed within this Chinese population.

Results

At the median follow‐up time of 60.5 months, median OS was 59.5 months in the pooled cohort. In the multivariate analysis, preoperative LDH >upper limit of normal (250 U/L) was the strongest independent prognostic factor for OS (HR 1.73, 95% confidence interval [CI], 1.22–2.44; p < 0.001). Patients with elevated LDH levels showed impaired OS than patients with normal LDH levels (27.6 months vs. 68.8 months). Five‐year survival rates were 53.7% and 22.5% in the LDH‐normal group and LDH‐high group, respectively. Similar results were also confirmed in each cohort. In the subgroup analysis, LDH could distinguish the survival regardless of most established prognostic factors (number and size of CRLM, surgical margin, extrahepatic metastases, CEA, and CA19‐9 levels, etc.). Integrating LDH into the Fong score contributed to an improvement in the predictive value.

Conclusion

Our study implicates serum LDH as a reliable and independent laboratory biomarker to predict the clinical outcome of curative‐intent surgery for CRLM. Composite of LDH and Fong score is a potential stratification tool for CRLM resection. Prospective, international studies are needed to validate these results across diverse populations.

Incidence and Risk Factors of Venous Thromboembolism Following Hepatectomy for Colorectal Metastases: A Population-Based Retrospective Cohort Study

BACKGROUND

Incidence of venous thromboembolism (VTE) following hepatectomy for colorectal cancer (CRC) metastases is unclear. These patients may represent a vulnerable population due to increased tumour burden. We aim to identify the risk of VTE development in routine clinical practice among patients with resected CRC liver metastases, the associated risk factors, and its impact on survival.

METHODS

We conducted a population-based retrospective cohort study of Ontario patients undergoing hepatectomy for CRC metastases between 2002 and 2009 using linked universal healthcare databases. Multivariable logistic regression was used to estimate the association between patient characteristics and VTE risk at 30 and 90-days after surgery. Cox proportional-hazards regression was used to estimate the association between VTE and adjusted cancer specific (CSS) and overall survival (OS).

RESULTS

1310 patients were included with a mean age of 63 ± 11. 62% were male. 51% had one metastatic deposit. Major hepatectomy occurred in 64%. VTE occurred in 4% within 90 days of liver resection. Only longer length of stay was associated with VTE development (OR 6.88 (2.57-18.43), p <0.001 for 15-21 days versus 0-7 days). 38% of VTEs were diagnosed after discharge, comprising 1.52% of the total cohort. VTE was not associated with inferior CSS or OS.

CONCLUSIONS

Risk of VTE development in this population is similar to those undergoing hepatectomy for other indications, and to the risk following other cancer site resections where post-operative extended VTE prophylaxis is currently recommended. The number of VTEs occurring after discharge suggests there may be a role for extended VTE prophylaxis.

Neoadjuvant chemotherapy for colorectal liver metastases: A contemporary review of the literature

Colorectal carcinoma (CRC) is one of the leading causes of cancer-related deaths worldwide, and up to 50% of patients with CRC develop colorectal liver metastases (CRLM). For these patients, surgical resection remains the only opportunity for cure and long-term survival. Over the past few decades, outcomes of patients with metastatic CRC have improved significantly due to advances in systemic therapy, as well as improvements in operative technique and perioperative care. Chemotherapy in the modern era of oxaliplatin- and irinotecan-containing regimens has been augmented by the introduction of targeted biologics and immunotherapeutic agents. The increasing efficacy of contemporary systemic therapies has led to an expansion in the proportion of patients eligible for curative-intent surgery. Consequently, the use of neoadjuvant strategies is becoming progressively more established. For patients with CRLM, the primary advantage of neoadjuvant chemotherapy (NCT) is the potential to down-stage metastatic disease in order to facilitate hepatic resection. On the other hand, the routine use of NCT for patients with resectable metastases remains controversial, especially given the potential risk of inducing chemotherapy-associated liver injury prior to hepatectomy. Current guidelines recommend upfront surgery in patients with initially resectable disease and low operative risk, reserving NCT for patients with borderline resectable or unresectable disease and high operative risk. Patients undergoing NCT require close monitoring for tumor response and conversion of CRLM to resectability. In light of the growing number of treatment options available to patients with metastatic CRC, it is generally agreed that these patients are best served at tertiary centers with an expert multidisciplinary team.

Molecular Determinants and Other Factors to Guide Selection of Patients for Hepatic Resection of Metastatic Colorectal Cancer

OPINION STATEMENT

Treatment for metastatic colorectal cancer (CRC) has changed significantly over the last few decades as cytotoxic and targeted chemotherapies have evolved and resection of (technically feasible) colorectal liver metastases (CRLM) has become standard of care for eligible patients. Overall, survival for metastatic CRC has considerably improved, but recurrences are common. Numerous clinical risk scores have been suggested to guide patient selection for CRLM resection, but none perfectly predict outcomes; therefore, a personalized approach to metastatic CRC treatment using genetic profiles for risk stratification and prognostication is a critically important advancement. All patients with suspected metastatic CRC should undergo genetic testing for common oncogene mutations (e.g., KRAS, BRAF, and NRAS) in addition to a triphasic CT scan of the chest, abdomen, and pelvis; if hepatectomy may be entertained and there is concern about the future liver remnant (FLR), liver volumetrics should also be performed. MRI and PET are useful adjuncts for cases in which diagnosis or extent of disease is unclear. The decision to operate should be individualized and based on each patient's condition, tumor biology, and technical resectability. Genetic profiles should be used to inform multidisciplinary meetings surrounding topics of chemotherapy and surgical resection, as well as patient discussions concerning the risks and benefits of surgery. In the end, most patients with technically resectable colorectal cancers and adequate cardiopulmonary fitness benefit from surgical resection, as it remains the only chance of long-term survival.

Risk scoring system for recurrence after simultaneous resection of colorectal cancer liver metastasis

Background

The simultaneous resection of synchronous colorectal cancer liver metastasis (SCRLM) has been widely applied. It is necessary to establish a risk scoring system to predict post-operative recurrence, especially in patients with neoadjuvant treatment.

Methods

The medical records of 221 patients undergoing simultaneous resection of CRLM were assessed in this study with a further 128 patients allocated to a validation group. All patients in the study group were classified according to their history of neoadjuvant treatment and univariate and multivariate analyses were applied to study independent risk factors. A score model was then generated according to the factors included. Our data set were also applied to validate three other existing scoring models [Fong clinical recurrence score (CRS), Konopke, and Zakaria disease-free survival (DFS) score], and the concordance index was calculated for comparison among these models.

Results

CRLM involving more than three nodes positive for a primary tumor was considered an independent risk factor for progression in patients without neoadjuvant treatment and all score models could discretely stratify patients according to disease free survival. In patients receiving neoadjuvant treatment, CRLM involving more than one node and transfusion invasion were major determinants in patients after treatment. However, only our scoring system and Fong’s CRS score could discretely discriminate patients. In the validation group, patients were significantly classified with the score system.

Conclusions

Existing score models had better values for determining prognosis in patients with SCRLM, especially in those undertaking neoadjuvant treatment. Larger cohorts, along with more detailed clinical features and multicenter validation should be undertaken before utilization.

Performance of two prognostic scores that incorporate genetic information to predict long-term outcomes following resection of colorectal cancer liver metastases: An external validation of the MD Anderson and JHH-MSK scores

INTRODUCTION

Two novel clinical risk scores (CRS) that incorporate KRAS mutation status were developed: modified CRS (mCRS) and GAME score. However, they have not been tested in large national and international cohorts. The aim of this study was to validate the prognostic discrimination utility and determine the clinical usefulness of the two novel CRS.

METHODS

Patients undergoing hepatectomy for CRLM (2000-2018) in 10 centers were included. The discriminatory abilities of mCRS, GAME, and Fong CRS were evaluated using Harrell's C-index and Akaike's Information Criterion.

RESULTS

In the entire cohort, the C-index of the GAME score (0.61) was significantly higher than those of Fong score (0.57) and mCRS (0.54), while the C-Index of mCRS was significantly lower than that of Fong score. When we compared the models in the various geographical regions, the C-index of GAME score was significantly higher than that of mCRS in North America, Europe, and South America. The AIC of Fong score, mCRS, and GAME score were 14 405, 14 447, and 14 319, respectively.

CONCLUSION

In conclusion, using the largest and most heterogenous population of CRLM patients with known KRAS status, this independent, external validation demonstrated that the GAME score outperforms both the traditional Fong score and mCRS.

Genomic and prognostic heterogeneity among RAS/BRAFV600E /TP53 co-mutated resectable colorectal liver metastases

Hepatic resection is potentially curative for patients with colorectal liver metastases, but the treatment benefit varies. KRAS/NRAS (RAS)/TP53 co‐mutations are associated with a poor prognosis after resection, but there is large variation in patient outcome within the mutation groups, and genetic testing is currently not used to evaluate benefit from surgery. We have investigated the potential for improved prognostic stratification by combined biomarker analysis with DNA copy number aberrations (CNAs), and taking tumor heterogeneity into account. We determined the mutation status of RAS, BRAF^V600, and TP53 in 441 liver lesions from 171 patients treated by partial hepatectomy for metastatic colorectal cancer. CNAs were profiled in 232 tumors from 67 of the patients. Mutations and high‐level amplifications of cancer‐critical genes, the latter including ERBB2 and EGFR, were predominantly homogeneous within patients. RAS/BRAF^V600E and TP53 co‐mutations were associated with a poor patient outcome (hazard ratio, HR, 3.9, 95% confidence interval, CI, 1.3–11.1, P = 0.012) in multivariable analyses with clinicopathological variables. The genome‐wide CNA burden and intrapatient intermetastatic CNA heterogeneity varied within the mutation groups, and the CNA burden had prognostic associations in univariable analysis. Combined prognostic analyses of RAS/BRAF^V600E/TP53 mutations and CNAs, either as a high CNA burden or high intermetastatic CNA heterogeneity, identified patients with a particularly poor outcome (co‐mutation/high CNA burden: HR 2.7, 95% CI 1.2–5.9, P = 0.013; co‐mutation/high CNA heterogeneity: HR 2.5, 95% CI 1.1–5.6, P = 0.022). In conclusion, DNA copy number profiling identified genomic and prognostic heterogeneity among patients with resectable colorectal liver metastases with co‐mutated RAS/BRAF^V600E/TP53.

Surgical Management of Colorectal Cancer Liver Metastases

Approximately 50% of colorectal cancer patients develop liver metastases. Hepatic metastases represent the most common cause of colorectal cancer-related mortality. Metastasectomy, if possible, represents the most effective treatment strategy; 20% of patients will be cured and more than 50% survive at least 5 years. Nuances to treatment planning hinge on whether patients present with resectable disease upfront, whether the future liver remnant is adequate, and whether the primary tumor, if present, is colon versus rectal in origin. This article discusses considerations impacting our approach to patients with colorectal liver metastases and the role for various multimodal treatment options.

Prognostic Impact of Pedicle Clamping during Liver Resection for Colorectal Metastases

Pedicle clamping (PC) during liver resection for colorectal metastases (CRLM) is used to reduce blood loss and allogeneic blood transfusion (ABT). The effect on long-term oncologic outcomes is still under debate. A retrospective analysis of the impact of PC on ABT-demand regarding overall (OS) and recurrence-free survival (RFS) in 336 patients undergoing curative resection for CRLM was carried out. Survival analysis was performed by both univariate and multivariate methods and propensity-score (PS) matching. PC was employed in 75 patients (22%). No increased postoperative morbidity was monitored. While the overall ABT-rate was comparable (35% vs. 37%, p = 0.786), a reduced demand for more than two ABT-units was observed (p = 0.046). PC-patients had better median OS (78 vs. 47 months, p = 0.005) and RFS (36 vs. 23 months, p = 0.006). Multivariate analysis revealed PC as an independent prognostic factor for OS (HR = 0.60; p = 0.009) and RFS (HR = 0.67; p = 0.017). For PC-patients, 1:2 PS-matching (N = 174) showed no differences in the overall ABT-rate compared to no-PC-patients (35% vs. 40%, p = 0.619), but a trend towards reduced transfusion requirement (>2 ABT-units: 9% vs. 21%, p = 0.052; >4 ABT-units: 2% vs. 11%, p = 0.037) and better survival (OS: 78 vs. 44 months, p = 0.088; RFS: 36 vs. 24 months; p = 0.029). Favorable long-term outcomes and lower rates of increased transfusion demand were observed in patients with PC undergoing resection for CRLM. Further prospective evaluation of potential oncologic benefits of PC in these patients may be meaningful.

Colorectal liver metastases: Current management and future perspectives

The liver is the commonest site of metastatic disease for patients with colorectal cancer, with at least 25% developing colorectal liver metastases (CRLM) during the course of their illness. The management of CRLM has evolved into a complex field requiring input from experienced members of a multi-disciplinary team involving radiology (cross sectional, nuclear medicine and interventional), Oncology, Liver surgery, Colorectal surgery, and Histopathology. Patient management is based on assessment of sophisticated clinical, radiological and biomarker information. Despite incomplete evidence in this very heterogeneous patient group, maximising resection of CRLM using all available techniques remains a key objective and provides the best chance of long-term survival and cure. To this end, liver resection is maximised by the use of downsizing chemotherapy, optimisation of liver remnant by portal vein embolization, associating liver partition and portal vein ligation for staged hepatectomy, and combining resection with ablation, in the context of improvements in the functional assessment of the future remnant liver. Liver resection may safely be carried out laparoscopically or open, and synchronously with, or before, colorectal surgery in selected patients. For unresectable patients, treatment options including systemic chemotherapy, targeted biological agents, intra-arterial infusion or bead delivered chemotherapy, tumour ablation, stereotactic radiotherapy, and selective internal radiotherapy contribute to improve survival and may convert initially unresectable patients to operability. Currently evolving areas include biomarker characterisation of tumours, the development of novel systemic agents targeting specific oncogenic pathways, and the potential re-emergence of radical surgical options such as liver transplantation.

Impact of multidisciplinary tumour boards (MTB) on the clinicopathological characteristics and outcomes of resected colorectal liver metastases across time

BACKGROUND

Resection of colorectal liver metastases (CLM) has been established as the standard of care. This study aims to compare the change in clinicopathological characteristics of patients who underwent curative resection of CLM across two time periods-2000 to 2010 (P1) and 2011 to 2016 (P2) and evaluate the prognostic impact of these characteristics on survival outcomes.

METHODS

Patients who undergo liver resection for CLM at Singapore General Hospital from January 2000 to December 2016 were identified from a prospectively maintained database. The primary end point was overall survival.

RESULTS

There were 183/318 (57.5%) patients and 135/318 (42.5%) patients in P1 and P2, respectively. There was a lower proportion of patients who had nodal metastases from primary colorectal cancer and clinical risk score (CRS) less than 3 in P2 when compared to P1. There was no difference in survival between both time periods. Independent predictors of survival for the cohort were CEA levels ≥ 200 ng/ml, primary tumour grade and lymph nodal status. Independent predictors of poor survival in P1 were poorly differentiated colorectal cancer and nodal metastases while in P2, independent predictors of poor survival were multiple liver metastases and nodal metastases.

CONCLUSION

Nodal metastases from primary colorectal cancer are an independent predictor of poor survival across time for resectable CLM. Although there is no difference in survival between the two time periods, patients with multiple liver metastases should be carefully considered prior to surgery as it is also an independent predictor of overall survival.

Distant Metastasis in Colorectal Cancer Patients-Do We Have New Predicting Clinicopathological and Molecular Biomarkers? A Comprehensive Review

Colorectal cancer (CRC) remains a serious health problem worldwide. Approximately half of patients will develop distant metastasis after CRC resection, usually with very poor prognosis afterwards. Because patient performance after distant metastasis surgery remains very heterogeneous, ranging from death within 2 years to a long-term cure, there is a clinical need for a precise risk stratification of patients to aid pre- and post-operative decisions. Furthermore, around 20% of identified CRC cases are at IV stage disease, known as a metastatic CRC (mCRC). In this review, we overview possible molecular and clinicopathological biomarkers that may provide prognostic and predictive information for patients with distant metastasis. These may comprise sidedness of the tumor, molecular profile and epigenetic characteristics of the primary tumor and arising metastatic CRC, and early markers reflecting cancer cell resistance in mCRC and biomarkers identified from transcriptome. This review discusses current stage in employment of these biomarkers in clinical practice as well as summarizes current experience in identifying predictive biomarkers in mCRC treatment.

Early T Stage Is Associated With Poor Prognosis in Patients With Metastatic Liver Colorectal Cancer

Clinically, a considerable portion of patients with early T stage who were supposed to have a low distant metastatic probability were diagnosed with metastatic liver colorectal cancer (CRLM). Our study aims to evaluate the prognostic value of the T stage for metastatic patients and establish a convenient individual assessment model for clinicians to explore preoperative predictors. The mRNA profiles of colorectal tumors (N = 19) were obtained by microarray at our clinical center. A total of 5,618 patients with CRLM from 2010 to 2015 were enrolled for the Surveillance, Epidemiology, and End Results (SEER) database. The cDNA microarray analyses showed that gene expression pattern in the T2N0M1 subgroup was significantly different from the T3/4N0M0 subgroup. In the survival analysis, metastatic patients with T1 stage surprisingly had much poorer prognosis than those with T3/T4 stage. Specifically, metastatic patients with early T stage were observed with higher frequency occurring at the rectum, better differentiation, less metastases in the lymph nodes, and a higher CEA level. Further survival analysis indicated that early T classification was an independent prognostic factor for a poor survival. When the lymph node (N) status was taken into consideration, patients with T1/2N+ had better survival than T1/2N0 patients. A clinical nomogram was constructed based on preoperative factors. The calibration curves showed a good concordance between nomogram prediction and actual observation. In conclusion, CRLM with early T stage had a different biological background. The prognosis of patients at T1/2M1 was poorer than at T3/4M1. More attention should be paid to the surveillance of high-risk factors and the screening of early T stage.

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.

Meta-analysis of the association between primary tumour location and prognosis after surgical resection of colorectal liver metastases

BACKGROUND

Primary tumour location is emerging as an important prognostic factor in localized and metastatic colorectal cancers. However, its prognostic role in colorectal liver metastasis (CRLM) after hepatectomy remains controversial. A systematic review and meta-analysis was undertaken to evaluate its prognostic value.

METHODS

References were identified through searches of PubMed, Embase, Web of Science and the Cochrane Library comparing overall or disease-free survival after hepatic resection between patients with CRLM originating from right- or left-sided colorectal cancers. Data were pooled using hazard ratios (HRs) and 95 per cent confidence intervals according to a random-effects model. Meta-regression and subgroup analyses were conducted to assess the effect of underlying confounding factors on HR estimates and to adjust for this.

RESULTS

The final analysis included 21 953 patients from 45 study cohorts. Compared with left-sided primary tumour location, right-sided location was associated with worse overall survival (HR 1·39, 95 per cent c.i. 1·28 to 1·51; P < 0·001; prediction interval 1·00 to 1·93), and also tended to have a negative impact on disease-free survival (HR 1·18, 1·06 to 1·32; P = 0·004; prediction interval 0·79 to 1·75). Subgroup analysis showed that the negative effect of right-sided primary tumour location on overall survival was more prominent in the non-Asian population (HR 1·47, 1·33 to 1·62) than the Asian population (HR 1·18, 1·05 to 1·32) (P for interaction <0·01).

CONCLUSION

This study demonstrated a prognostic role for primary tumour location in patients with CRLM receiving hepatectomy, especially regarding overall survival. Adding primary tumour location may provide important optimization of prognosis prediction models for CRLM in current use.

Total circulating cell-free DNA as a prognostic biomarker in metastatic colorectal cancer before first-line oxaliplatin-based chemotherapy

BACKGROUND

Metastatic colorectal cancer (mCRC) is a heterogeneous disease where prognosis is dependent both on tumor biology and host factors. Total circulating cell-free DNA (cfDNA) has shown to harbor prognostic information in mCRC, although less is known about the biological correlates of cfDNA levels in this patient group. The primary objective was to evaluate the prognostic value of pretreatment cfDNA in patients receiving the first-line oxaliplatin-based chemotherapy for mCRC, by using a predefined upper limit of normal (ULN) from a cohort of presumed healthy individuals. The secondary objective was to model cfDNA levels as a function of predefined tumor and host factors.

PATIENTS AND METHODS

This was a retrospective post hoc study based on a prospective multicenter phase III trial, the NORDIC-VII study. DNA was purified from 547 plasma samples and cfDNA quantified by a droplet digital PCR assay (B2M, PPIA) with controls for lymphocyte contamination. Main clinical end point was overall survival (OS).

RESULTS

cfDNA was quantified in 493 patients, 54 were excluded mainly due to lymphocyte contamination. Median cfDNA level was 7673 alleles/ml (1050-1 645 000) for B2M and 5959 alleles/ml (555-854 167) for PPIA. High cfDNA levels were associated with impaired outcome; median OS of 16.6 months for levels above ULN and 25.9 months for levels below ULN (hazard ratio = 1.83, 95% confidence interval 1.51-2.21, P < 0.001). The result was confirmed in multivariate OS analysis adjusting for established clinicopathological characteristics. A linear regression model predicted cfDNA levels from sum of longest tumor diameters by RECIST, the presence of liver metastases and systemic inflammatory response as measured by interleukin 6 (F(6, 357) = 62.7, P < 0.001).

CONCLUSION

cfDNA holds promise as a minimally invasive and clinically relevant prognostic biomarker in mCRC before initiating first-line oxaliplatin-based chemotherapy and may be a complex entity associated with tumor burden, liver metastases and systemic inflammatory response.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT00145314.

Colorectal liver metastases: An update on multidisciplinary approach

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

Stereotactic Radiotherapy for Oligometastasis

Oligometastatic disease is defined as “a condition with a few metastases arising from tumors that have not acquired a potential for widespread metastases.” Its behavior suggests a transitional malignant state somewhere between localized and metastatic cancer. Treatment of oligometastatic disease is expected to achieve long-term local control and to improve survival. Historically, patients with oligometastases have often undergone surgical resection since it was anecdotally believed that surgical resection could result in progression-free or overall survival benefits. To date, no prospective randomized trials have demonstrated surgery-related survival benefits. Short courses of highly focused, extremely high-dose radiotherapies (e.g., stereotactic radiosurgery and stereotactic ablative body radiotherapy (SABR)) have frequently been used as alternatives to surgery for treatment of oligometastasis. A randomized study has demonstrated the overall survival benefits of stereotactic radiosurgery for solitary brain metastasis. Following the success of stereotactic radiosurgery, SABR has been widely accepted for treating extracranial metastases, considering its efficacy and minimum invasiveness. In this review, we discuss the history of and rationale for the local treatment of oligometastases and probe into the implementation of SABR for oligometastatic disease.

Proposal of Two Prognostic Models for the Prediction of 10-Year Survival after Liver Resection for Colorectal Metastases

Background

One-third of 5-year survivors after liver resection for colorectal liver metastases (CLM) develop recurrence or tumor-related death. Therefore 10-year survival appears more adequate in defining permanent cure. The aim of this study was to develop prognostic models for the prediction of 10-year survival after liver resection for colorectal liver metastases.

Methods

N=965 cases of liver resection for CLM were retrospectively analyzed using univariable and multivariable regression analyses. Receiver operating curve analyses were used to assess the sensitivity and specificity of developed prognostic models and their potential clinical usefulness.

Results

The 10-year survival rate was 15.2%. Age at liver resection, application of chemotherapies of the primary tumor, preoperative Quick's value, hemoglobin level, and grading of the primary colorectal tumor were independent significant predictors for 10-year patient survival. The generated formula to predict 10-year survival based on these preoperative factors displayed an area under the receiver operating curve (AUROC) of 0.716. In regard to perioperative variables, the distance of resection margins and performance of right segmental liver resection were additional independent predictors for 10-year survival. The logit link formula generated with pre- and perioperative variables showed an AUROC of 0.761.

Conclusion

Both prognostic models are potentially clinically useful (AUROCs >0.700) for the prediction of 10-year survival. External validation is required prior to the introduction of these models in clinical patient counselling.

Genetic And Morphological Evaluation (GAME) score for patients with colorectal liver metastases

BACKGROUND

This study sought to develop a clinical risk score for resectable colorectal liver metastasis (CRLM) by combining clinicopathological and clinically available biological indicators, including KRAS.

METHODS

A cohort of patients who underwent resection for CRLM at the Johns Hopkins Hospital (JHH) was analysed to identify independent predictors of overall survival (OS) that can be assessed before operation; these factors were combined into the Genetic And Morphological Evaluation (GAME) score. The score was compared with the current standard (Fong score) and validated in an external cohort of patients from the Memorial Sloan Kettering Cancer Center (MSKCC).

RESULTS

Six preoperative predictors of worse OS were identified on multivariable Cox regression analysis in the JHH cohort (502 patients). The GAME score was calculated by allocating points to each patient according to the presence of these predictive factors: KRAS-mutated tumours (1 point); carcinoembryonic antigen level 20 ng/ml or more (1 point), primary tumour lymph node metastasis (1 point); Tumour Burden Score between 3 and 8 (1 point) or 9 and over (2 points); and extrahepatic disease (2 points). The high-risk group in the JHH cohort (GAME score at least 4 points) had a 5-year OS rate of 11 per cent, compared with 73·4 per cent for those in the low-risk group (score 0-1 point). Importantly, in cohorts from both the JHH and MSKCC (747 patients), the discriminatory capacity of the GAME score was superior to that of the Fong score, as demonstrated by the C-index and the Akaike information criterion.

CONCLUSION

The GAME score is a preoperative prognostic tool that can be used to inform treatment selection.

Histopathological growth patterns as a candidate biomarker for immunomodulatory therapy

The encroachment of a growing tumor upon the cells and structures of surrounding normal tissue results in a series of histopathological growth patterns (HGPs). These morphological changes can be assessed in hematoxylin-and-eosin (H&E) stained tissue sections from primary and metastatic tumors and have been characterized in a range of tissue types including liver, lung, lymph node and skin. HGPs in different tissues share certain general characteristics like the extent of angiogenesis, but also appropriate tissue-specific mechanisms which ultimately determine differences in the biology of HGP subtypes. For instance, in the well-characterized HGPs of liver metastases, the two main subtypes, replacement and desmoplastic, recapitulate two responses of the normal liver to injury: regeneration and fibrosis. HGP subtypes have distinct cytokine profiles and differing levels of lymphocytic infiltration which suggests that they are indicative of immune status in the tumor microenvironment. HGPs predict response to bevacizumab and are associated with overall survival (OS) after surgery for liver metastases in colorectal cancer (CRC). In addition, HGPs can change over time in response to therapy. With standard scoring methods being developed, HGPs represent an easily accessible, dynamic biomarker to consider when determining strategies for treatment using anti-VEGF and immunomodulatory drugs.

Personalizing prognosis in colorectal cancer: A systematic review of the quality and nature of clinical prognostic tools for survival outcomes

Integrating diverse types of prognostic information into accurate, individualized estimates of outcome in colorectal cancer is challenging. Significant heterogeneity in colorectal cancer prognostication tool quality exists. Methodology is incompletely or inadequately reported. Evaluations of the internal or external validity of the prognostic model are rarely performed. Prognostication tools are important devices for patient management, but tool reliability is compromised by poor quality. Guidance for future development of prognostication tools in colorectal cancer is needed.

Case-controlled study comparing peri-operative and cancer-related outcomes after major hepatectomy and parenchymal sparing hepatectomy for metastatic colorectal cancer

INTRODUCTION

Liver resection is potentially curative in selected patients with colorectal liver metastases (CLM). There has been a trend towards parenchyma sparing hepatectomy (PSH) rather than major hepatectomy (MH) due to lower perioperative morbidity. Although data from retrospective series suggest that long-term survival after PSM are similar to MH, these reports may be subject to selection bias. The aim of this study was to compare outcomes of PSH and MH in a case-controlled study.

PATIENTS AND METHODS

917 consecutive patients who underwent liver resection for CLM during 2000-2010 were identified from a prospective database. 238 patients who underwent PSH were case-matched with 238 patients who had MH, for age, gender, tumour number, maximum tumour diameter, primary Dukes' stage, synchronicity and chemotherapy status using a propensity scoring system. Peri-operative outcomes, recurrence and long-term survival were compared.

RESULTS

Fewer PSH patients received peri-operative blood transfusions (p < 0.0001). MH patients had greater incidence of complications (p = 0.04), grade III/IV complications (p = 0.01) and 90-day mortality (p = 0.03). Hospital stay was greater in the MH group (p = 0.04). There was no difference in overall/disease-free survival.

CONCLUSION

Patients with resectable CLM should be offered PSH if technically feasible. PSH is safer than MH without compromising long-term survival.

If a picture is worth a thousand words, take a good look at the picture: Survival after liver metastasectomy for colorectal cancer

INTRODUCTION

An analysis of NHS data published in by Morris et al. in 2010 is widely used as evidence in support of liver metastasectomy for colorectal cancer and its wider application. Recent evidence concerning better overall survival for patients with metastatic colorectal cancer challenges the notional assumptions about what survival would be without metastasectomy. Earlier detection of metastases for local treatments has not resulted in a survival benefit.

MATERIALS AND METHODS

The interpretation of its central graphical display is critically reviewed and the common the limitations of the analysis of registry data and resulting immortal time bias are explored.

RESULTS AND DISCUSSION

Recent evidence, including the 2017 CLOCC trial report make the original interpretation of the analysis suspect. Randomised trials are essential to detect a treatment effect of specific interventions among variable disease progression, selection bias, and multiple and repeated treatments that are inherent in the management of advanced cancer.

Precision surgery for colorectal liver metastases: Opportunities and challenges of omics-based decision making

Precision surgery involves improving patient selection to ensure that surgical intervention that is proven to benefit on a population level is the optimal treatment for each individual patient. For patients with colorectal liver metastases (CRLM), existing prognostic scoring systems rely on well-recognised histopathological features such as size and number of lesions. Advances in preoperative imaging algorithms mean that increasingly low volume disease can be detected, improving assessment of these factors. In addition, novel imaging modalities mean that underlying tumour biology and metabolic behaviour during therapy can be assessed. Molecular analysis of tumours can provide crucial prognostic information, with the critical role of RAS/RAF mutations in prognosis well recognised. The optimal source of tissue for this level of analysis is debated, with good concordance between primary and metastatic lesions for some recognised prognostic factors but marked discrepancies for a variety of other relevant mutations. As well as mutational heterogeneity between primary and metastatic lesions, heterogeneity within tumours and dynamic changes in tumour biology over time present a significant challenge in assessing tumour for prognostic biomarkers. Circulating tumour cells offer one potential method of longitudinal tumour analysis, but are limited by current technologies. This review article summarises some of the key advances in prognostication for patients with resectable colorectal liver metastases, as well as highlighting the potential limitations of such an approach.

The expanding role of stereotactic body radiation therapy in oligometastatic solid tumors: What do we know and where are we going?

The spectrum hypothesis posits that there are distinct clinical states of metastatic progression. Early data suggest that aggressive treatment of more biologically indolent metastatic disease, characterized by metastases limited in number and destination organ, may offer an opportunity to alter the disease course, potentially allowing for longer survival, delay of systemic therapy, or even cure. The development of stereotactic body radiation therapy (SBRT) has opened new avenues for the treatment of oligometastatic disease. Early data support the use of SBRT for treating oligometastases in a number of organs, with promising rates of treated metastasis control and overall survival. Ongoing investigation is required to definitively establish benefit, determine the appropriate treatment regimen, refine patient selection, and incorporate SBRT with systemic therapies.

Resection of Liver Metastases in Colorectal Cancer in the Era of Expanding Systemic Therapy

About 25% of patients with colorectal cancer develop liver metastases after resection of the primary tumor, and surgical resection of the metastases offers the only opportunity for long-term survival. However, only 20% of patients present with resectable disease. Deciding which patients should be offered surgery, and which should receive additional treatment in the form of perioperative chemotherapy, is complex. For the majority of patients who present with technically irresectable liver-limited disease, systemic downsizing chemotherapy offers the only opportunity to reach surgery and potential cure. Molecular analysis of tumor tissue is improving patient stratification, allowing more appropriate treatment selection, but is not yet a regular part of clinical practice. Decision making is limited by a lack of clear prospective evidence, and so multidisciplinary team assessment is essential to optimize outcomes.

Imaging oligometastatic cancer before local treatment

With the advent of novel treatment strategies to help widen the therapeutic window for patients with oligometastatic cancer, improved biomarkers are needed to reliably define patients who can benefit from these treatments. Multimodal imaging is one such option and should be optimised to comprehensively assess metastatic sites, disease burden, and response to neoadjuvant treatment in each disease setting. These features will probably remain important prognostic biomarkers, and are crucial in planning multidisciplinary treatment. There are opportunities to extract additional phenotypic information from conventional imaging, while novel imaging techniques can also reveal specific aspects of tumour biology. Imaging can both characterise and localise the phenotypic heterogeneity of multiple tumour sites. Novel approaches to existing imaging datasets and correlation with tumour biology will be important in realising the potential of imaging to guide treatment in the oligometastatic setting. In this Personal View, we discuss the current status and future directions of imaging before treatment in patients with extracranial oligometastases.