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

Radiomics and machine learning analysis by computed tomography and magnetic resonance imaging in colorectal liver metastases prognostic assessment

OBJECTIVE

The aim of this study was the evaluation radiomics analysis efficacy performed using computed tomography (CT) and magnetic resonance imaging in the prediction of colorectal liver metastases patterns linked to patient prognosis: tumor growth front; grade; tumor budding; mucinous type. Moreover, the prediction of liver recurrence was also evaluated.

METHODS

The retrospective study included an internal and validation dataset; the first was composed by 119 liver metastases from 49 patients while the second consisted to 28 patients with single lesion. Radiomic features were extracted using PyRadiomics. Univariate and multivariate approaches including machine learning algorithms were employed.

RESULTS

The best predictor to identify tumor growth was the Wavelet_HLH_glcm_MaximumProbability with an accuracy of 84% and to detect recurrence the best predictor was wavelet_HLH_ngtdm_Complexity with an accuracy of 90%, both extracted by T1-weigthed arterial phase sequence. The best predictor to detect tumor budding was the wavelet_LLH_glcm_Imc1 with an accuracy of 88% and to identify mucinous type was wavelet_LLH_glcm_JointEntropy with an accuracy of 92%, both calculated on T2-weigthed sequence. An increase statistically significant of accuracy (90%) was obtained using a linear weighted combination of 15 predictors extracted by T2-weigthed images to detect tumor front growth. An increase statistically significant of accuracy at 93% was obtained using a linear weighted combination of 11 predictors by the T1-weigthed arterial phase sequence to classify tumor budding. An increase statistically significant of accuracy at 97% was obtained using a linear weighted combination of 16 predictors extracted on CT to detect recurrence. An increase statistically significant of accuracy was obtained in the tumor budding identification considering a K-nearest neighbors and the 11 significant features extracted T1-weigthed arterial phase sequence.

CONCLUSIONS

The results confirmed the Radiomics capacity to recognize clinical and histopathological prognostic features that should influence the choice of treatments in colorectal liver metastases patients to obtain a more personalized therapy.

Colorectal liver metastases patients prognostic assessment: prospects and limits of radiomics and radiogenomics

In this narrative review, we reported un up-to-date on the role of radiomics to assess prognostic features, which can impact on the liver metastases patient treatment choice. In the liver metastases patients, the possibility to assess mutational status (RAS or MSI), the tumor growth pattern and the histological subtype (NOS or mucinous) allows a better treatment selection to avoid unnecessary therapies. However, today, the detection of these features require an invasive approach. Recently, radiomics analysis application has improved rapidly, with a consequent growing interest in the oncological field. Radiomics analysis allows the textural characteristics assessment, which are correlated to biological data. This approach is captivating since it should allow to extract biological data from the radiological images, without invasive approach, so that to reduce costs and time, avoiding any risk for the patients. Several studies showed the ability of Radiomics to identify mutational status, tumor growth pattern and histological type in colorectal liver metastases. Although, radiomics analysis in a non-invasive and repeatable way, however features as the poor standardization and generalization of clinical studies results limit the translation of this analysis into clinical practice. Clear limits are data-quality control, reproducibility, repeatability, generalizability of results, and issues related to model overfitting.

Dynamic radiomics for predicting the efficacy of antiangiogenic therapy in colorectal liver metastases

Background and objective

For patients with advanced colorectal liver metastases (CRLMs) receiving first-line anti-angiogenic therapy, an accurate, rapid and noninvasive indicator is urgently needed to predict its efficacy. In previous studies, dynamic radiomics predicted more accurately than conventional radiomics. Therefore, it is necessary to establish a dynamic radiomics efficacy prediction model for antiangiogenic therapy to provide more accurate guidance for clinical diagnosis and treatment decisions.

Methods

In this study, we use dynamic radiomics feature extraction method that extracts static features using tomographic images of different sequences of the same patient and then quantifies them into new dynamic features for the prediction of treatmentefficacy. In this retrospective study, we collected 76 patients who were diagnosed with unresectable CRLM between June 2016 and June 2021 in the First Hospital of China Medical University. All patients received standard treatment regimen of bevacizumab combined with chemotherapy in the first-line treatment, and contrast-enhanced abdominal CT (CECT) scans were performed before treatment. Patients with multiple primary lesions as well as missing clinical or imaging information were excluded. Area Under Curve (AUC) and accuracy were used to evaluate model performance. Regions of interest (ROIs) were independently delineated by two radiologists to extract radiomics features. Three machine learning algorithms were used to construct two scores based on the best response and progression-free survival (PFS).

Results

For the task that predict the best response patients will achieve after treatment, by using ROC curve analysis, it can be seen that the relative change rate (RCR) feature performed best among all features and best in linear discriminantanalysis (AUC: 0.945 and accuracy: 0.855). In terms of predicting PFS, the Kaplan-Meier plots suggested that the score constructed using the RCR features could significantly distinguish patients with good response from those with poor response (Two-sided P<0.0001 for survival analysis).

Conclusions

This study demonstrates that the application of dynamic radiomics features can better predict the efficacy of CRLM patients receiving antiangiogenic therapy compared with conventional radiomics features. It allows patients to have a more accurate assessment of the effect of medical treatment before receiving treatment, and this assessment method is noninvasive, rapid, and less expensive. Dynamic radiomics model provides stronger guidance for the selection of treatment options and precision medicine.

The prognostic significance of clinicopathological characteristics in early-onset versus late-onset colorectal cancer liver metastases

PURPOSE

This study aimed to explore the prognostic significance of clinicopathological characteristics in early-onset versus late-onset colorectal liver metastases (CRLM).

METHODS

The data of CRLM patients who underwent hepatectomy from September 2010 to September 2020 were retrospectively analyzed. According to the age of primary cancer diagnosis, patients were divided into early-onset CRLM (EOCRLM) and late-onset CRLM (LOCRLM) groups. Clinicopathological parameters were compared between the two groups. Cox regression model and Kaplan-Meier method were used to analyze the effect of clinicopathological parameters on overall survival (OS) and recurrence-free survival (RFS).

RESULTS

In total, 431 CRLM patients were identified, 130 with EOCRLM and 301 with LOCRLM. Compared with LOCRLM patients, EOCRLM patients had lower American Society of Anesthesia (ASA) grade and longer operation time (204 vs. 179 min). More aggressive features were presented in EOCRLM patients including synchronous liver metastases (76.9% vs. 61.1%) and bilobar involvement (43.8% vs. 33.2%). No significant difference in OS or RFS was found between the two groups. Multivariate analysis of EOCRLM group showed that preoperative CA19-9 level and RAS/BRAF status were predictive of OS, while bilobar involvement and preoperative CEA level were associated with RFS. In LOCRLM group, the number of CRLM, preoperative CA19-9 level, and BRAF status were associated with OS, while the number of CRLM was associated with RFS.

CONCLUSIONS

The preoperative CA19-9 level, RAS/BRAF status, bilobar involvement, and preoperative CEA level were predictive of EOCRLM patient prognosis, while the number of CRLM, preoperative CA19-9 level, and BRAF status were predictive of LOCRLM patient prognosis.

Potential for cure and predictors of long-term survival after radiofrequency ablation for colorectal liver metastases: A 20-years single-center experience

BACKGROUND

Additional radiofrequency ablation (RFA) of liver-limited colorectal liver metastases (CRLM) improves overall (OS) and recurrence-free survival (RFS) over systemic therapy alone. We aimed to assess the potential and predictive factors of long-term survival and cure to optimize patient selection for RFA application.

METHODS

Retrospective review of a prospectively maintained single-center database of consecutive patients undergoing RFA for liver-limited CRLM after systemic therapy between 2002 and 2020. Clinicopathologic characteristics and KRAS/BRAF-genotype data (tested routinely since 2010) were correlated to RFS and OS. Cure was defined as ≥10-years RFS (long-term survival as ≥5-years OS) following RFA.

RESULTS

For the entire cohort of 158 patients (median follow-up 13.6 years), co-occurrence of three factors, RECIST-defined response, number of ≤3 CRLM, and ≤3 cm maximum size determined a survival plateau that distinguished cured from non-cured patients (10-years RFS: 15.5% vs 0%, p < 0.0001). Among 59 patients (37.3%) being tested, 4(6.8%) were BRAF-mt, 15(25.4%) KRAS-mt, and 40(67.8%) KRAS/BRAF-wt. OS (median follow-up 8.3 years) was estimated to be higher with KRAS/BRAF-wt compared to a mutant KRAS or BRAF status (5-years OS: 22.8% vs 3.4%, p = 0.0018).

CONCLUSION

This study indicates about 15% chance of cure following RFA of low-volume liver-limited CRLM after downsizing by systemic therapy and a negative effect of KRAS or BRAF mutation on long-term survival after CRLM ablation. These findings may improve clinical decision-making in patients potentially candidate to RFA of CRLM and encourage further investigations on molecular factors determining an oligometastatic state of CRLM curable with focal ablative therapy.

Development and external validation of a radiomics combined with clinical nomogram for preoperative prediction prognosis of resectable pancreatic ductal adenocarcinoma patients

PURPOSE

To develop and externally validate a prognosis nomogram based on contrast-enhanced computed tomography (CECT) combined clinical for preoperative prognosis prediction of patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

184 patients from Center A with histopathologically confirmed PDAC who underwent CECT were included and allocated to training cohort (n=111) and internal validation cohort (n=28). The radiomic score (Rad - score) for predicting overall survival (OS) was constructed by using the least absolute shrinkage and selection operator (LASSO). Univariate and multivariable Cox regression analysis was used to construct clinic-pathologic features. Finally, a radiomics nomogram incorporating the Rad - score and clinical features was established. External validation was performed using Center B dataset (n = 45). The validation of nomogram was evaluated by calibration curve, Harrell's concordance index (C-index) and decision curve analysis (DCA). The Kaplan-Meier (K-M) method was used for OS analysis.

RESULTS

Univariate and multivariate analysis indicated that Rad - score, preoperative CA 19-9 and postoperative American Joint Committee on Cancer (AJCC) TNM stage were significant prognostic factors. The nomogram based on Rad - score and preoperative CA19-9 was found to exhibit excellent prediction ability: in the training cohort, C-index was superior to that of the preoperative CA19-9 (0.713 vs 0.616, P< 0.001) and AJCC TNM stage (0.713 vs 0.614, P< 0.001); the C-index was also had good performance in the validation cohort compared with CA19-9 (internal validation cohort: 0.694 vs 0.555, P< 0.001; external validation cohort: 0.684 vs 0.607, P< 0.001) and AJCC TNM stage (internal validation cohort: 0.694 vs 0.563, P< 0.001; external validation cohort: 0.684 vs 0.596, P< 0.001). The calibration plot and DCA showed excellent predictive accuracy in the validation cohort.

CONCLUSION

We established a well-designed nomogram to accurately predict OS of PDAC preoperatively. The nomogram showed a satisfactory prediction effect and was worthy of further evaluation in the future.

Implications of RAS Mutations on Oncological Outcomes of Surgical Resection and Thermal Ablation Techniques in the Treatment of Colorectal Liver Metastases

Simple Summary

Modern management of colorectal liver metastases (CRLM) requires a thorough knowledge of tumor biology and oncogenes mutations. RAS mutations are of paramount interest for the indication of targeted therapies and is increasingly considered as a negative prognostic factor for patients undergoing surgical resection or ablation for CRLM. Several studies discussed the results of specific technical considerations according to RAS mutational status on the oncological outcomes after surgical resection/ablation for CRLM. We reviewed the available data on the real impact of RAS mutations on the prognosis with special regard to the need of a tailored surgical (ablation) approach according to tumoral biology.

Abstract

Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cause of cancer-related death. More than 50% of patients with CRC will develop liver metastases (CRLM) during their disease. In the era of precision surgery for CRLM, several advances have been made in the multimodal management of this disease. Surgical treatment, combined with a modern chemotherapy regimen and targeted therapies, is the only potential curative treatment. Unfortunately, 70% of patients treated for CRLM experience recurrence. RAS mutations are associated with worse overall and recurrence-free survival. Other mutations such as BRAF, associated RAS /TP53 and APC/PIK3CA mutations are important genetic markers to evaluate tumor biology. Somatic mutations are of paramount interest for tailoring preoperative treatment, defining a surgical resection strategy and the indication for ablation techniques. Herein, the most relevant studies dealing with RAS mutations and the management of CRLM were reviewed. Controversies about the implication of this mutation in surgical and ablative treatments were also discussed.

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.

Discordance of KRAS Mutational Status between Primary Tumors and Liver Metastases in Colorectal Cancer: Impact on Long-Term Survival Following Radical Resection

Simple Summary

KRAS mutational heterogeneity between primary colorectal cancer and liver metastases may present a challenge in assessing prognostic information prior to the multimodal treatment. Aim of our study is to assess the incidence of KRAS discordance in a single-center series by comparing primary colorectal tumor specimens with the corresponding liver metastasis. Mutation analyses in all patients were performed at the same institution. Impact of discordance on overall survival and risk factors associated with discordance were analyzed. Our study showed that KRAS discordance was observed in 15.9% of patients. In patients with wild-type colorectal primary tumors, subsequent acquisition of mutation in the corresponding liver metastasis was associated with worse overall survival and was significantly more frequently found in patients with multiple liver metastases. These results suggested that, in the era of precision medicine, the possibility of KRAS discordance should be taken into account within the multidisciplinary management of patients with metastatic colorectal cancer.

Abstract

If KRAS mutation status of primary colorectal tumor is representative of corresponding colorectal liver metastases (CRLM) mutational pattern, is controversial. Several studies have reported different rates of KRAS discordance, ranging from 4 to 32%. Aim of this study is to assess the incidence of discordance and its impact on overall survival (OS) in a homogenous group of patients. KRAS mutation status was evaluated in 107 patients resected for both primary colorectal tumor and corresponding CRLM at the same institution, between 2007 and 2018. Discordance rate was 15.9%. Its incidence varied according to the time interval between the two mutation analyses (p = 0.025; Pearson correlation = 0.2) and it was significantly higher during the first 6 months from the time of primary tumor evaluation. On multivariable analysis, type of discordance (wild-type in primary tumor, mutation in CRLM) was the strongest predictor of poor OS (p < 0.001). At multivariable logistic regression analysis, the number of CRLM >3 was an independent risk factor for the risk of KRAS discordance associated with the worst prognosis (OR = 4.600; p = 0.047). Results of our study suggested that, in the era of precision medicine, possibility of KRAS discordance should be taken into account within multidisciplinary management of patients with metastatic colorectal cancer.

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.

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.

Development and assessment of an individualized nomogram to predict colorectal cancer liver metastases

Background

This article aims to develop and assess the radiomics paradigm for predicting colorectal cancer liver metastasis (CRLM) from the primary tumor.

Methods

This retrospective study included 100 patients from the First Hospital of Jilin University from June 2017 to December 2017. The 100 patients comprised 50 patients with and 50 without CRLM. The maximum-level enhanced computed tomography (CT) image of primary cancer in the portal venous phase of each patient was selected as the original image data. To automatically implement radiomics-related paradigms, we developed a toolkit called Radiomics Intelligent Analysis Toolkit (RIAT).

Results

With RIAT, the model based on logistic regression (LR) using both the radiomics and clinical information signatures showed the maximum net benefit. The area under the curve (AUC) value was 0.90±0.02 (sensitivity =0.85±0.02, specificity =0.79±0.04) for the training set, 0.86±0.11 (sensitivity =0.85±0.09, specificity =0.75±0.19) for the verification set, 0.906 (95% CI, 0.840-0.971; sensitivity =0.81, specificity =0.84) for the cross-validation set, and 0.899 (95% CI, 0.761-1.000; sensitivity =0.78, specificity =0.91) for the test set.

Conclusions

The radiomics nomogram-based LR with clinical risk and radiomics features allows for a more accurate classification of CRLM using CT images with RIAT.

Prognostic impact of K-RAS mutational status and primary tumor location in patients undergoing resection for colorectal cancer liver metastases: an update

Aim: To determine the impact of KRAS mutation status on survival in patients undergoing surgery for colorectal liver metastases (CLM). Patients & methods: Patients with resected CLM and KRAS mutations. Survival was compared between mt-KRAS and wt-KRAS. Results: Of 662 patients, 174 (26.3%) were mt-KRAS and 488 (73.7%) wt-KRAS. mt-KRAS patients had significantly lower recurrence-free survival (HR: 1.42; 95% CI: 1.10-1.84). There were no differences between the groups for sidedness. Poorer survival was associated with mt-KRAS with positive lymph nodes, >1 metastases, tumors >5 cm, synchronous tumors and R1-R2. Conclusion: KRAS mutation status can help predict recurrence-free survival. Primary tumor location was not a prognostic factor after resection. KRAS mutation status can help design a multidisciplinary approach after curative resection of CLM.

Circulating cell-free long DNA fragments predict post-hepatectomy recurrence of colorectal liver metastases

INTRODUCTION

Most patients with colorectal liver metastases, who undergo hepatectomy, experience recurrence. Although the prognosis is poorer for patients with early recurrence (within 6 months after hepatectomy) compared with later recurrence, no biomarker has been identified to predict early recurrence. Minimal residual disease (MRD) in patients who undergo curative surgery is the main cause of recurrence. In cancer patients, long fragment cell-free DNA is detected, and the presence of long fragments of cell-free DNA after surgery can indicate MRD. In this study, we developed a novel biomarker to predict early recurrence of colorectal liver metastases using cell-free DNA.

MATERIALS AND METHODS

Forty-one patients with colorectal liver metastases were enrolled. Peripheral blood samples were collected before and at 1 month after hepatectomy. Cell-free DNA was extracted from 1 ml plasma, and the long fragment/β-globin ratio, which can indicate MRD, was measured by real-time polymerase chain reaction.

RESULTS

Three of 21 patients (14.3%) with decreases in the long cell-free DNA fragment/β-globin ratio after hepatectomy developed early recurrence compared with twelve of 20 patients (60.0%) with an increased ratio (P = 0.002). Patients with a decreased long fragment/β-globin ratio after hepatectomy had significantly longer recurrence-free survival compared with patients with an increased ratio (366 vs 102 days, P < 0.001).

CONCLUSION

The cell-free DNA long fragment/β-globin ratio may serve as an effective biomarker of early recurrence in patients with colorectal liver metastases, who undergo hepatectomy.

Preoperative Leucocyte-Based Inflammatory Scores in Patients with Colorectal Liver Metastases: Can We Count on Them?

BACKGROUND

Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR) have been identified as potential prognostic factors for overall survival (OS) in primary colorectal cancer, and there is a growing interest in their use in colorectal liver metastases (CLMs). However, optimal cut-off values for these ratios have not been defined by making comparison between series difficult. This study aimed to confirm the prognostic value of inflammatory scores in patients undergoing resection for CLM.

METHODS

We retrospectively analysed data from 376 consecutive patients who underwent liver surgery for CLM between June 2010 and August 2015. We assessed the reproducibility of previously published ratios and determined new cut-off values using the Cut-off Finder web-based tool. Relations between cut-off values and OS were analysed with Kaplan-Meier log-rank survival analysis and multivariate Cox models.

RESULTS

Three hundred and forty-three patients had full preoperative blood tests for calculation of NLR, PLR and LMR. The number of cut-off values which showed a significant discrimination for OS was 49/249 (19.7%) for NLR, 28/316 (8.9%) for PLR and 22/214 (10.3%) for LMR, all with a scattered nonlinear distribution.

CONCLUSIONS

This study showed that inflammatory scores expressed as ratios do not seem to be consistently reliable prognostic markers in patients with resectable CLM.

Prognostic and predictive markers in liver limited stage IV colorectal cancer

Colorectal cancer is the third most commonly diagnosed cancer among both men and women. Personalised treatment options remain complex, although there is broad agreement over which patients with colorectal liver metastases (CRLM) should and should not be offered resection. Decisions on an optimal management strategy involves careful assessment of both technical and oncological factors. In this review we aim to summarise current prognostic biomarkers for metastatic colorectal cancers, specifically patients considered for resection. A number of clinico-pathological factors have been identified as prognostically important with good internal validity, but limited external validity. Furthermore, these prognostic scoring systems do not take factor in modern chemotherapeutic agents and the disease modification these agents produce. Histopathological response to chemotherapy is of significant prognostic importance. Molecular markers can help predict the efficacy of a biological agent. An important prognostic factor of liver metastasis is the recognition that location of the primary colorectal cancer impacts on metastatic phenotype and represents difference in genotype, i.e. proximal tumours are more aggressive than distal tumours with an increased likelihood of disease progression. Several mutational molecular markers identified include microsatellite instability, BRAF, and KRAS/NRAS and combination mutations, which confer poorer outcomes. Accurate prognostication in patients with liver limited colorectal metastases remains crucial, as this allows tailoring treatment options to each disease and improving outcomes. Access to tissue before treatment remains a limitation although advances in ability to assess tumour biology by non-invasive methods are promising.

Nomogram predicted disease free survival for colorectal liver metastasis patients with preoperative chemotherapy followed by hepatic resection

BACKGROUND

Hepatic resection is regarded to as a potentially curative option for colorectal cancer liver metastases (CRLM), but it is associated with a high rate of recurrence. The present study intended to establish an effective nomogram to predict disease free survival (DFS) and select candidates of hepatic resection.

METHODS

The nomogram was based on a retrospective study on 447 CRLM patients treated with preoperative chemotherapy followed by hepatic resection using a multicentric database between January 1st, 2010 and December 31st, 2017. Results were validated using bootstrap resampling on 117 patients. The predictive accuracy and discriminative ability of the nomogram were determined by concordance index (C-index) and calibration curve. Overall survival, disease free survival, and local recurrence rate for patients with colorectal cancer were measured.

RESULTS

Based on multivariate analysis of the primary cohort, independent factors for DFS included tumor size larger than 5 cm, multiple liver metastases(>1), RAS mutation, primary lymph node metastasis and tumor size increase after preoperative chemotherapy. These five factors were all considered in the nomogram. The C-index of the nomogram for predicting survival was 0.675. With external validation, the C-index of the nomogram for the prediction of the DFS was 0.77, which demonstrated that this model has a good level of discriminative ability. For the 382 patients (66.7%) who developed recurrence, the optimal cutoff point for early recurrence was determined to be 12 months after hepatic resection.

CONCLUSIONS

The proposed nomogram demonstrated accurate prognostic prediction of DFS for CRLM patients with preoperative chemotherapy followed by hepatic resection.

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.

Molecular and Immunohistochemical Markers with Prognostic and Predictive Significance in Liver Metastases from Colorectal Carcinoma

Despite the significant recent achievements in the diagnosis and treatment of colorectal cancer (CRC), the prognosis of these patients has currently plateaued. During the past few years, the opportunity to consider multiple treatment modalities (including surgery and other locoregional treatments, systemic therapy, and targeted therapy) led to the research of novel prognostic and predictive biomarkers in CRC liver metastases (CRCLM) patients. In this review, we seek to describe the current state of knowledge of CRCLM biomarkers and to outline impending clinical perspectives, in particular focusing on the cutting-edge tools available for their characterization.

Inflammation and cancer: What a surgical oncologist should know

Chronic inflammation is an aberrantly prolonged form of a protective response to a loss of tissue homeostasis and it is involved in several steps of the carcinogenesis process. As a result, many cancers are inflammation-related. The systemic inflammatory response is associated with survival in advanced and localized cancers. Two categories of scores have been proposed to monitor the systemic inflammatory response, those derived from protein measurement and those based on counting inflammatory cells. This review aims to provide a critical appraisal of these 2 categories of surrogate markers. The 3 scale modified Glasgow prognostic score (mGPS) is based on the combination of C-reactive protein and albumin and is graded 0 to 2. It has been validated worldwide showing an independent prognostic value in patients with cancer in a variety of tumour types and tumour stages. Leukocytes-based scores are mainly neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR). Elevated NLR and/or PLR and lower LMR seem to be associated with decreased survival, but the studies about these markers are very heterogeneous. The main limit is the variety of thresholds used to dichotomize patients, so that reproducibility and reliability of leukocytes-based scores can be questioned. Hence, there is no sufficient evidence to support their use in clinical practice. Comprehensive management of patients with operable and advanced cancer should integrate the host systemic inflammatory response by calculating the mGPS. It could be a helpful tool to tailor patients' management.

Colorectal cancer liver metastases - a population-based study on incidence, management and survival

BACKGROUND

Colorectal cancer (CRC) is a leading cause of cancer-associated deaths with liver metastases developing in 25-30% of those affected. Previous data suggest a survival difference between right- and left-sided liver metastatic CRC, even though left-sided cancer has a higher incidence of liver metastases. The aim of the study was to describe the liver metastatic patterns and survival as a function of the characteristics of the primary tumour and different combinations of metastatic disease.

METHODS

A retrospective population-based study was performed on a cohort of patients diagnosed with CRC in the region of Stockholm, Sweden during 2008. Patients were identified through the Swedish National Quality Registry for Colorectal Cancer Treatment (SCRCR) and additional information on intra- and extra-hepatic metastatic pattern and treatment were retrieved from electronic patient records. Patients were followed for 5 years or until death. Factors influencing overall survival (OS) were investigated by means of Cox regression. OS was compared using Kaplan-Meier estimations and the log-rank test.

RESULTS

Liver metastases were diagnosed in 272/1026 (26.5%) patients within five years of diagnosis of the primary. Liver and lung metastases were more often diagnosed in left-sided colon cancer compared to right-sided cancer (28.4% versus 22.1%, p = 0.029 and 19.7% versus 13.2%, p = 0.010, respectively) but the extent of liver metastases were more extensive for right-sided cancer as compared to left-sided (p = 0.001). Liver metastatic left-sided cancer, including rectal cancer, was associated with a 44% decreased mortality risk compared to right-sided cancer (HR = 0.56, 95% CI: 0.39-0.79) with a 5-year OS of 16.6% versus 4.3% (p < 0.001). In liver metastatic CRC, the presence of lung metastases did not significantly influence OS as assessed by multivariate analysis (HR = 1.11, 95% CI: 0.80-1.53).

CONCLUSION

The worse survival in liver metastatic right-sided colon cancer could possibly be explained by the higher number of metastases, as well as more extensive segmental involvement compared with left-sided colon and rectal cancer, even though the latter had a higher incidence of liver metastases. Detailed population-based data on the metastatic pattern of CRC and survival could assist in more structured and individualized guidelines for follow-up of patients with CRC.