Dangerous halo after neoadjuvant chemotherapy and two-step hepatectomy for colorectal liver metastases

Prediction of transformation in the histopathological growth pattern of colorectal liver metastases after chemotherapy using CT-based radiomics

Chemotherapy alters the prognostic biomarker histopathological growth pattern (HGP) phenotype in colorectal liver metastases (CRLMs) patients. We aimed to develop a CT-based radiomics model to predict the transformation of the HGP phenotype after chemotherapy. This study included 181 patients with 298 CRLMs who underwent preoperative contrast-enhanced CT followed by partial hepatectomy between January 2007 and July 2022 at two institutions. HGPs were categorized as pure desmoplastic HGP (pdHGP) or non-pdHGP. The samples were allocated to training, internal validation, and external validation cohorts comprising 153, 65, and 29 CRLMs, respectively. Radiomics analysis was performed on pre-enhanced, arterial phase, portal venous phase (PVP), and fused images. The model was used to predict prechemotherapy HGPs in 112 CRLMs, and HGP transformation was analysed by comparing these findings with postchemotherapy HGPs determined pathologically. The prevalence of pdHGP was 19.8% (23/116) and 45.8% (70/153) in chemonaïve and postchemotherapy patients, respectively (P < 0.001). The PVP radiomics signature showed good performance in distinguishing pdHGP from non-pdHGPs (AUCs of 0.906, 0.877, and 0.805 in the training, internal validation, and external validation cohorts, respectively). The prevalence of prechemotherapy pdHGP predicted by the radiomics model was 33.0% (37/112), and the prevalence of postchemotherapy pdHGP according to the pathological analysis was 47.3% (53/112; P = 0.029). The transformation of HGP was bidirectional, with 15.2% (17/112) of CRLMs transforming from prechemotherapy pdHGP to postchemotherapy non-pdHGP and 30.4% (34/112) transforming from prechemotherapy non-pdHGP to postchemotherapy pdHGP (P = 0.005). CT-based radiomics method can be used to effectively predict the HGP transformation in chemotherapy-treated CRLM patients, thereby providing a basis for treatment decisions.

Histopathological growth patterns and tumor-infiltrating lymphocytes in breast cancer liver metastases

Liver is the third most common organ for breast cancer (BC) metastasis. Two main histopathological growth patterns (HGP) exist in liver metastases (LM): desmoplastic and replacement. Although a reduced immunotherapy efficacy is reported in patients with LM, tumor-infiltrating lymphocytes (TIL) have not yet been investigated in BCLM. Here, we evaluate the distribution of the HGP and TIL in BCLM, and their association with clinicopathological variables and survival. We collect samples from surgically resected BCLM (n = 133 patients, 568 H&E sections) and post-mortem derived BCLM (n = 23 patients, 97 H&E sections). HGP is assessed as the proportion of tumor liver interface and categorized as pure-replacement ('pure r-HGP') or any-desmoplastic ('any d-HGP'). We score the TIL according to LM-specific guidelines. Associations with progression-free (PFS) and overall survival (OS) are assessed using Cox regressions. We observe a higher prevalence of 'any d-HGP' (56%) in the surgical samples and a higher prevalence of 'pure r-HGP' (83%) in the post-mortem samples. In the surgical cohort, no evidence of the association between HGP and clinicopathological characteristics is observed except with the laterality of the primary tumor (p value = 0.049) and the systemic preoperative treatment before liver surgery (p value = .039). TIL is less prevalent in 'pure r-HGP' as compared to 'any d-HGP' (p value = 0.001). 'Pure r-HGP' predicts worse PFS (HR: 2.65; CI: (1.45-4.82); p value = 0.001) and OS (HR: 3.10; CI: (1.29-7.46); p value = 0.011) in the multivariable analyses. To conclude, we demonstrate that BCLM with a 'pure r-HGP' is associated with less TIL and with the worse outcome when compared with BCLM with 'any d-HGP'. These findings suggest that HGP could be considered to refine treatment approaches.

Mapping Tumor Heterogeneity via Local Entropy Assessment: Making Biomarkers Visible

Advanced imaging and analysis improve prediction of pathology data and outcomes in several tumors, with entropy-based measures being among the most promising biomarkers. However, entropy is often perceived as statistical data lacking clinical significance. We aimed to generate a voxel-by-voxel visual map of local tumor entropy, thus allowing to (1) make entropy explainable and accessible to clinicians; (2) disclose and quantitively characterize any intra-tumoral entropy heterogeneity; (3) evaluate associations between entropy and pathology data. We analyzed the portal phase of preoperative CT of 20 patients undergoing liver surgery for colorectal metastases. A three-dimensional core kernel (5 × 5 × 5 voxels) was created and used to compute the local entropy value for each voxel of the tumor. The map was encoded with a color palette. We performed two analyses: (a) qualitative assessment of tumors' detectability and pattern of entropy distribution; (b) quantitative analysis of the entropy values distribution. The latter data were compared with standard Hounsfield data as predictors of post-chemotherapy tumor regression grade (TRG). Entropy maps were successfully built for all tumors. Metastases were qualitatively hyper-entropic compared to surrounding parenchyma. In four cases hyper-entropic areas exceeded the tumor margin visible at CT. We identified four "entropic" patterns: homogeneous, inhomogeneous, peripheral rim, and mixed. At quantitative analysis, entropy-derived data (percentiles/mean/median/root mean square) predicted TRG (p < 0.05) better than Hounsfield-derived ones (p = n.s.). We present a standardized imaging technique to visualize tumor heterogeneity built on a voxel-by-voxel entropy assessment. The association of local entropy with pathology data supports its role as a biomarker.

Correlation between magnetic resonance images of peritumor margin enhancement and prognosis in hepatocellular carcinoma after drug-eluting bead transcatheter arterial chemoembolization

Purpose

The aim of this study is to investigate the morphological characteristics and clinical significance of magnetic resonance (MR) images of peritumor margin enhancement in hepatocellular carcinoma (HCC) after drug-eluting bead transcatheter arterial chemoembolization (DEB-TACE).

Methods

From January 2017 to December 2020, a total of 162 patients who received a diagnosis of HCC were included in our study. We began the follow-up with magnetic resonance imaging (MRI) for complete response assessment, and peritumor margin enhancements were classified as sharp and rough types according to morphology. During the follow-up, data such as progression or remission of the two enhancement modalities, morphological changes in terms of margin enhancements observed in MR images, and alpha-fetoprotein (AFP) levels were recorded.

Results

In the follow-up period of 36 months, 70 and 92 patients with sharp- and rough-type peritumor margins, respectively, were observed. At the end of the follow-up, patients with sharp-type margins had lower AFP levels and longer progression-free survival than those with rough-type margins (P &lt; 0.05). Furthermore, the sharp-type margin was thinner than the rough-type margin (all P &lt; 0.05). Moreover, the sharp-type group had a high incidence of tumors with a diameter of &lt; 5 cm, whereas the rough-type group had a high incidence of tumors with a diameter of ≥ 5 cm. Continuous enhancements of peritumor margins in MRI were greater in the sharp-type group than in the rough-type group. Most of the patients with a sharp-type margin achieved disease remission (94.3%, P &lt; 0.05), whereas most of those with a rough-type margin experienced disease progression (84.8%, P &lt; 0.05).

Conclusions

Patients with HCC with a sharp-type margin enhancement on MRI after DEB-TACE mostly demonstrated benign lesions with a good prognosis, whereas those with a rough-type margin mostly demonstrated malignant growth.

Precision Surgery of Colorectal Liver Metastases in the Current Era: A Systematic Review

Liver resection for colorectal liver metastases (CRLM) is widely considered the treatment with the highest curative potential. However, not all patients derive the same oncological benefit, underlining the need for better patient stratification and treatment allocation. In this context, we performed a systematic review of the literature to determine the role of RAS status in selecting the optimal surgical strategy. Evidence comparing anatomical with non-anatomical resections depending on RAS mutational status was scarce and conflicting, with two studies reporting superiority in mutated RAS (mutRAS) patients and two studies reporting equivalent outcomes. The rate of incomplete microscopic resection (R1) was found to be increased among mutRAS patients, possibly due to higher micrometastatic spread lateral to the primary lesion. The impact of R1 resection margins was evaluated separately for mutRAS and wild-type patients in three studies, of which, two indicated an additive detriment to long-term survival in the former group. In the current era of precision surgery, RAS status can be utilized to predict the efficacy of liver resection in the treatment of CRLM, avoiding a potentially morbid operation in patients with adverse tumor profiles.

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

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

Histopathological growth patterns of liver metastasis: updated consensus guidelines for pattern scoring, perspectives and recent mechanistic insights

The first consensus guidelines for scoring the histopathological growth patterns (HGPs) of liver metastases were established in 2017. Since then, numerous studies have applied these guidelines, have further substantiated the potential clinical value of the HGPs in patients with liver metastases from various tumour types and are starting to shed light on the biology of the distinct HGPs. In the present guidelines, we give an overview of these studies, discuss novel strategies for predicting the HGPs of liver metastases, such as deep-learning algorithms for whole-slide histopathology images and medical imaging, and highlight liver metastasis animal models that exhibit features of the different HGPs. Based on a pooled analysis of large cohorts of patients with liver-metastatic colorectal cancer, we propose a new cut-off to categorise patients according to the HGPs. An up-to-date standard method for HGP assessment within liver metastases is also presented with the aim of incorporating HGPs into the decision-making processes surrounding the treatment of patients with liver-metastatic cancer. Finally, we propose hypotheses on the cellular and molecular mechanisms that drive the biology of the different HGPs, opening some exciting preclinical and clinical research perspectives.

CT, MRI, and radiomics studies of liver metastasis histopathological growth patterns: an up-to-date review

The histopathological growth patterns (HGPs) of liver metastases (LMs) are independently associated with the long-term prognosis of the primary tumor, with different HGPs predicting different patient outcomes and clinical treatment decisions. Non-invasive imaging biomarkers for stratification of HGPs are beneficial for treatment monitoring, evaluation of efficacy, and prognosis prediction of LMs. This review describes the state of research regarding computed tomography (CT), magnetic resonance imaging (MRI), and radiomics imaging biomarkers for LM-HGPs; discusses the advantages of CT, MRI, and radiomics for classification of LM-HGPs; and provides a reference for the stratification of LM-HGPs. Finally, the difficulties and deficiencies of CT, MRI, and radiomics in LM-HGP research are summarized along with the proposed directions for future research.

Pathological Evaluation of Resected Colorectal Liver Metastases: mFOLFOX6 Plus Bevacizumab versus mFOLFOX6 Plus Cetuximab in the Phase II ATOM Trial

We compared the preplanned histopathological responses of resected liver metastases from patients who received modified FOLFOX6 plus bevacizumab or modified FOLFOX6 plus cetuximab for liver-limited colorectal metastases in the ATOM trial. Fibrosis and viable tumor cells in tumor regression grade (TRG), infarct-like necrosis in modified TRG (mTRG), and dangerous halo (DH) were assessed. Fifty-five patients (28 and 27 patients in the bevacizumab and cetuximab arms, respectively) were divided into the low (viable tumor cells ≤ 50%) and high (>50%) TRG or mTRG groups. DH was characterized as absent/rare or focal/diffuse. Compared to the bevacizumab arm, the cetuximab arm was more effective, with respect to low TRG (13 vs. 23 patients) and absent/rare DH (14 vs. 19 patients), respectively. Low mTRG was similarly observed in both arms. Low TRG/mTRG and absent/rare DH showed better relapse-free survival (RFS) than high TRG/mTRG and focal/diffuse DH. In the bevacizumab arm, a significant difference in RFS existed between the low and high TRG groups, while in the cetuximab arm, for TRG, mTRG, and DH, the low and absent/rare groups demonstrated significantly longer RFS than the high and focal/diffuse groups, respectively. TRG could estimate RFS in patients who underwent liver metastasectomy after bevacizumab or cetuximab chemotherapy.

The desmoplastic growth pattern is associated with second-stage completion and longer survival in 2-stage hepatectomy for colorectal cancer liver metastases

BACKGROUND

Two-stage hepatectomy for bilobar colorectal cancer liver metastases is potentially curative for selected patients. Histological growth patterns of colorectal liver metastases (desmoplastic, replacement, and pushing) have prognostic value. Our aim was to evaluate their association with pathologic response to preoperative treatment, second-stage hepatectomy completion, and survival in patients treated with a curative-intent 2-stage hepatectomy.

METHODS

In 67 patients planned for 2-stage hepatectomy, colorectal liver metastases resected from the first-stage hepatectomy were retrospectively evaluated for growth patterns and pathologic response according to Tumor Regression Grading, modified Tumor Regression Grading, and Blazer grading. Tumor Regression Grading 1 to 3, modified Tumor Regression Grading 1 to 3, and Blazer 0 and 1 defined good responders.

RESULTS

Desmoplastic growth patterns (GP) were more frequent among good responders (P < .001). Second-stage hepatectomy completion was associated with desmoplastic growth patterns and pathologic response on univariate analysis and multivariable analyses (P = .017 and P = .041, respectively). Median follow-up was 84 months (95% confidence interval: 53.4 [not reached]). Nondesmoplastic GP patients and nonresponders had a poorer overall survival (hazard ratio = 3.86, 95% confidence interval: 2.11-7.07, P < .001 and hazard ratio = 2.14, 95% confidence interval: 1.19-3.83, P = .009, respectively) on univariate analysis. Nondesmoplastic growth pattern was the only factor associated with a poorer overall survival on multivariable analysis (hazard ratio = 4.17, 95% confidence interval: 1.79-9.74, P < .001). Nondesmoplastic GP was also associated with a poorer recurrence-free survival (hazard ratio = 2.05, 95% confidence interval: 1.13-3.70, P = .017).

CONCLUSION

Desmoplastic GP could represent a useful morphological marker for early identification of patients who might benefit from 2-stage hepatectomy completion.

A Comprehensive Prognostic Model for Colorectal Cancer Liver Metastasis Recurrence After Neoadjuvant Chemotherapy

Background

For patients with colorectal cancer liver metastases (CRLMs), it is important to stratify patients according to the risk of recurrence. This study aimed to validate the predictive value of some clinical, imaging, and pathology biomarkers and develop an operational prognostic model for patients with CRLMs with neoadjuvant chemotherapy (NACT) before the liver resection.

Methods

Patients with CRLMs accompanied with primary lesion and liver metastases lesion resection were enrolled into this study. A nomogram based on independent risk factors was identified by Kaplan–Meier analysis and multivariate Cox proportional hazard analysis. The predictive ability was evaluated by receiver operating characteristic (ROC) curves and decision curve analysis (DCA). Calibration plot were also used to explore the consistency between prediction and reality.

Results

A total of 118 patients were enrolled into the study. Multivariable Cox analysis found that histopathological growth patterns (HGPs) [Hazard Rate (HR) = 2.130], radiology response (stable disease vs. partial response, HR = 2.207; progressive disease vs. partial response, HR = 3.824), lymph node status (HR = 1.442), and age (HR = 0.576) were independent risk factors for disease-free survival (DFS) (p < 0.05). Corresponding nomogram was constructed on the basis of the above factors, demonstrating that scores ranging from 5 to 11 presented better prognosis than the scores of 0–4 (median DFS = 14.3 vs. 4.9 months, p < 0.0001). The area under ROC curves of the model for 1-, 2-, and 3-year DFS were 0.754, 0.705, and 0.666, respectively, and DCA confirmed that the risk model showed more clinical benefits than clinical risk score. Calibration plot for the probability of DFS at 1 or 3 years verified an optimal agreement between prediction and actual observation. In the course of our research, compared with pure NACT, a higher proportion of desmoplastic HGP (dHGP) was detected in patients treated with NACT plus cetuximab (p = 0.030), and the use of cetuximab was an independent factor for decreased replacement HGP (rHGP) and increased dHGP (p = 0.049).

Conclusion

Our model is concise, comprehensive, and high efficient, which may contribute to better predicting the prognosis of patients with CRLMs with NACT before the liver resection. In addition, we observed an unbalanced distribution of HGPs as well.

The Histopathological Growth Pattern of Colorectal Liver Metastases Impacts Local Recurrence Risk and the Adequate Width of the Surgical Margin

BACKGROUND

The histopathological growth pattern (HGP) of colorectal liver metastases (CLM) has been associated with prognosis. This study was designed to elucidate if the HGP is associated with local recurrence risk and impacts the adequate width of surgical margin.

METHODS

All consecutive patients resected for CLM in 2018-2019 were considered. HGP was prospectively classified as follows: desmoplastic, pushing, and replacement. Surgical margin was classified as follows: R0 (margin ≥ 1 mm), R1vasc (0-mm margin, tumor detachment from intrahepatic vessels), and R1par (tumor exposure along transection plane). R0 resections were further distinguished in R0min (1-mm margin) and R0wide (> 1-mm margin).

RESULTS

A total of 340 resection areas in 136 patients were analyzed (70 R0min, 143 R0wide, 31 R1vasc, 96 R1par). HGP was desmoplastic in 26 cases, pushing in 221, and replacement in 93. Thirty-six local recurrences occurred (11%, median follow-up 21 months): 1 after R0wide, 4 after R0min, 3 after R1vasc, and 28 after R1par resection. In R1par group, local recurrence rate was high independently of HGP (29%). In R1vasc and R0min groups, local recurrence risk was higher in the replacement group (R1vasc: 29% vs. 4% if pushing/desmoplastic; R0min: 11% vs. 4%). In R0wide group, local recurrence risk was low for all HGP ( < 1%). Independent predictors of local recurrence were replacement HGP (odds ratio = 1.654, P = 0.036), and R1par resection (odds ratio = 57.209, P < 0.001 vs. R0).

CONCLUSIONS

Replacement HGP is associated with an increased risk of local recurrence. In these patients, a wide surgical margin should be pursued, because R1vasc and R0min resections could be insufficient. R1par resection is inadequate, independently of the HGP.

Is precision medicine for colorectal liver metastases still a utopia? New perspectives by modern biomarkers, radiomics, and artificial intelligence

The management of patients with liver metastases from colorectal cancer is still debated. Several therapeutic options and treatment strategies are available for an extremely heterogeneous clinical scenario. Adequate prediction of patients’ outcomes and of the effectiveness of chemotherapy and loco-regional treatments are crucial to reach a precision medicine approach. This has been an unmet need for a long time, but recent studies have opened new perspectives. New morphological biomarkers have been identified. The dynamic evaluation of the metastases across a time interval, with or without chemotherapy, provided a reliable assessment of the tumor biology. Genetics have been explored and, thanks to their strong association with prognosis, have the potential to drive treatment planning. The liver-tumor interface has been identified as one of the main determinants of tumor progression, and its components, in particular the immune infiltrate, are the focus of major research. Image mining and analyses provided new insights on tumor biology and are expected to have a relevant impact on clinical practice. Artificial intelligence is a further step forward. The present paper depicts the evolution of clinical decision-making for patients affected by colorectal liver metastases, facing modern biomarkers and innovative opportunities that will characterize the evolution of clinical research and practice in the next few years.

Liver-First Approach for Synchronous Colorectal Metastases: Analysis of 7360 Patients from the LiverMetSurvey Registry

Background

The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to elucidate the outcome of the liver-first approach and to identify patients who benefit at most from this approach.

Methods

Patients with synchronous CRLM included in the LiverMetSurvey registry between 2000 and 2017 were considered. Three strategies were analyzed, i.e. liver-first approach, colorectal resection followed by liver resection (primary-first), and simultaneous resection, and three groups of patients were analyzed, i.e. solitary metastasis, multiple unilobar CRLM, and multiple bilobar CRLM. In each group, patients from the three strategy groups were matched by propensity score analysis.

Results

Overall, 7360 patients were analyzed: 4415 primary-first, 552 liver-first, and 2393 simultaneous resections. Compared with the other groups, the liver-first group had more rectal tumors (58.0% vs. 31.2%) and higher hepatic tumor burden (more than three CRLMs: 34.8% vs. 24.0%; size > 50 mm: 35.6% vs. 22.8%; p < 0.001). In patients with solitary and multiple unilobar CRLM, survival was similar regardless of treatment strategy, whereas in patients with multiple bilobar metastases, the liver-first approach was an independent positive prognostic factor, both in unmatched patients (3-year survival 65.9% vs. primary-first 60.4%: hazard ratio [HR] 1.321, p = 0.031; vs. simultaneous resections 54.4%: HR 1.624, p < 0.001) and after propensity score matching (vs. primary-first: HR 1.667, p = 0.017; vs. simultaneous resections: HR 2.278, p = 0.003).

Conclusion

In patients with synchronous CRLM, the surgical strategy should be decided according to the hepatic tumor burden. In the presence of multiple bilobar CRLM, the liver-first approach is associated with longer survival than the alternative approaches and should be evaluated as standard.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-10220-w.

Infiltrative tumour growth pattern correlates with poor outcome in oesophageal cancer

Objective

Oesophageal cancer (OEC) is an aggressive disease with a poor survival rate. Prognostic markers are thus urgently needed. Due to the demonstrated prognostic value of histopathological growth pattern (HGP) in other cancers, we performed a retrospective assessment of HGP in patients suffering from invasive OEC.

Design

A first cohort composed of 89 treatment-naïve operated patients with OEC from The Cancer Genome Atlas (TCGA) public database was constituted, from which H&E images and RNA-sequencing data were retrieved. Next, a second cohort composed of 99 patients with OEC treated and operated in a Belgian hospital was established. H&E-stained sections and extracted tumorous RNA were obtained from the samples. HGP were assessed on H&E slides as infiltrative (IGP) or expansive (EGP). TCGA RNA-sequencing data were analysed through the gene set enrichment analysis and Cytoscape softwares. Real-time quantitative PCR (qPCR) experiments were performed to assess gene expression in the Belgian cohort.

Results

IGP patients displayed a grim prognosis compared with EGP patients, while IGP was found as associated with numerous lymphovascular emboli and perinervous infiltrations. Analyses of the TCGA expression data showed that angiogenesis, epithelial-to-mesenchymal transition (EMT) and inflammation were significantly upregulated in IGP compared with EGP samples. qPCR experiments of three genes appearing as highly upregulated in each pathway showed no difference in expression according to the HGP.

Conclusion

The current study demonstrates the poor prognostic value carried by IGP in OC and suggests angiogenesis, EMT and inflammation as key carcinogenetic pathways upregulated in this pattern.

Breast cancer liver metastasis: current and future treatment approaches

Nearly all fatalities arising from breast tumors are attributable to distant metastases. Breast cancer liver metastasis (BCLM) is associated with poor prognoses, with the median survival time being 2 to 3 years. Tumor intrinsic subtype directs preferential metastasis to specific organs, with HER2-enriched tumors demonstrating the highest rates of metastasis to the liver, though all subtypes can grow in the liver. There is no singular established standard-of-care for BCLM; therapeutic selection is driven by histologic and molecular hallmarks of the primary tumor or biopsied metastasis samples. Given the poor prognosis of patients with hepatic spread, pre-clinical studies are necessary to identify and evaluate promising new treatment strategies. It is critical that these laboratory studies accurately recapitulate the BCLM disease process, standard progression, and histological attributes. In this review, we summarize the histologic and molecular characteristics of BCLM, evaluate the efficacy of existing surgical and medical treatment strategies, and discuss future approaches to preclinical study of BCLM.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

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

Colorectal liver metastases: radiopathological correlation

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

Can medical imaging identify the histopathological growth patterns of liver metastases?

The histopathological growth patterns (HGPs) of liver metastases of colorectal cancer and of several other tumor types predict outcome of patients in multiple studies. The HGPs of liver metastases have a prognostic but also a predictive value with one of the growth patterns, the replacement growth pattern, related to resistance to systemic treatment. Given that the HGP can only be assessed in a reliable manner when a surgical resection of the metastasis has been performed, this biomarker cannot be exploited to the full. For example, HGPs can at this moment, not be used to decide whether patients with liver metastatic breast or colorectal cancer will benefit or not from locoregional treatment, such as surgery or radiotherapy, and from peri-operative systemic treatment. In this review we highlight studies that suggest that the HGPs of liver metastases can be identified by medical imaging. Although still to be confirmed by a prospective multicenter approach, some studies indeed achieve a high accuracy in predicting the HGPs by applying radiomic algorithms on CT- or MR-images of liver metastases. This is an important step towards a treatment planning of patients with liver metastatic cancer that takes into account the biology and the progression kinetics of the metastases.

Radio-Pathological Correlations in Patients with Liver Metastases for Colorectal Cancer

BACKGROUND

Colorectal cancer (CRC) is the most frequent gastrointestinal cancer. The liver is the organ most commonly affected by CRC metastases. Synchronous CRC liver metastases (CRCLM) are present in 15-25% at diagnosis, and metastases are confined to the liver in 70-80% of these cases. The aim of the present study was to investigate the existence of significant correlations between the pathological features and computed tomography scan morpho-densitometric findings.

SUMMARY

A retrospective study of prospectively collected data has been performed; all patients underwent curative-intent hepatic resection from January 2004 to December 2012 and had histologically confirmed CRCLM. Key Messages: Thirty-four (57%) patients were males; the mean age was 64.4 (±10.2) years. Statistically significant differences have been found with the percentages of intra-tumoral fibrosis (p = 0.038) and necrosis (p = 0.007); the values of fibrosis are higher in the absence of a peri-lesional ring, while those of necrosis are higher in the presence of a peri-lesional ring.There was a correlation between the histopathological response to treatments and the global attenuation levels observed in the computed tomography scan of CRCLM. Furthermore, the presence of a radiologically evidenced peripheral ring was associated with the amount of viable tumor cells in the periphery of the tumor, and with responses predominated by necrosis. More studies are needed to clarify the radiological and histological correlation and to be able to better select patients who are going to undergo surgery.

Current state of the art imaging approaches for colorectal liver metastasis

One of the most common cancers worldwide, colorectal cancer (CRC) has been associated with significant morbidity and mortality and therefore represents an enormous burden to the health care system. Recent advances in CRC treatments have provided patients with primary and metastatic CRC a better long-term prognosis. The presence of synchronous or metachronous metastasis has been associated, however, with worse survival. The most common site of metastatic disease is the liver. A variety of treatment modalities aimed at targeting colorectal liver metastases (CRLM) has been demonstrated to improve the prognosis of these patients. Loco-regional approaches such as surgical resection and tumor ablation (operative and percutaneous) can provide patients with a chance at long-term disease control and even cure in select populations. Patient selection is important in defining the most suitable treatment option for CRLM in order to provide the best possible survival benefit while avoiding unnecessary interventions and adverse events. Medical imaging plays a crucial role in evaluating the characteristics of CRLMs and disease resectability. Size of tumors, proximity to adjacent anatomical structures, and volume of the unaffected liver are among the most important imaging parameters to determine the suitability of patients for surgical management or other appropriate treatment approaches. We herein provide a comprehensive overview of current-state-of-the-art imaging in the management of CRLM, including staging, treatment planning, response and survival assessment, and post-treatment surveillance. Computed tomography (CT) scan and magnetic resonance imaging (MRI) are two most commonly used techniques, which can be used solely or in combination with functional imaging modalities such as positron emission tomography (PET) and diffusion weighted imaging (DWI). Providing up-to-date evidence on advantages and disadvantages of imaging modalities and tumor assessment criteria, the current review offers a practice guide to assist providers in choosing the most suitable imaging approach for patients with CRLM.

Prognostic value of ADC measurements in predicting overall survival in patients undergoing 90Y radioembolization for colorectal cancer liver metastases

AIM

To assess the ability of diffusion-weighted imaging (DWI) in predicting the overall survival in patients who underwent Yttrium 90 radioembolization (⁹⁰Y-RE) for colorectal liver metastases (CLM) with other well-established clinical and imaging parameters by comparing the pre- and post-treatment apparent diffusion coefficient (ADC) values of the lesions.

METHODS

A total of 81 metastatic lesions of 27 consecutive patients who underwent DWI before and after the ⁹⁰Y-RE session were enrolled in the study. ADC values were calculated from the entire (ADC_e) and peripheral (ADC_p) tumor on pre- and post-treatment DWI, and any relative increase in ADC >0% accepted as a functional imaging response. The impact of functional imaging response in addition to other well-known parameters including Response Evaluation Criteria in Solid Tumors (RECIST), hepatic tumor burden, Eastern Cooperative Oncology Group performance status (ECOG-PS) and the presence of extrahepatic metastases in predicting overall survival (OS) was assessed using Kaplan-Meier curves and Cox-regression analyses.

RESULTS

The median OS of the patients was 10 months (range, 6-20 months) while the median OS of the responders being significantly longer than the non-responders for ADC_e and ADC_p (median 11 vs 7 months, P = 0.003; median 12 vs. 7 months, P < 0.0001, respectively). The RECIST score was also significantly affected the OS (progressive or stable disease median 8 months vs. partial response 15 indent months, P = 0.019). The other parameters including hepatic tumor burden, gender, ECOG score, the involvement of the liver lobes, and the presence of extrahepatic metastases were not associated with the OS. In multivariate analysis, only ADC_p remained as an independent predictor of OS (P = 0.003, HR = 19.878).

CONCLUSION

Any increase in relative ADC_p or ADC_e values after Y90-RE treatment was associated with longer OS in CLM patients, and DWI seems to be valuable imaging biomarker in predicting OS in CLM patients during the early post-interventional period after ⁹⁰Y-RE.

Correlation between CT morphologic appearance and histologic findings in colorectal liver metastasis after preoperative chemotherapy

PURPOSE

Radiological evaluation of the efficacy of preoperative chemotherapy for colorectal liver metastasis (CRLM) is the most important tool for determining treatment strategies. The aim of this study was to identify a correlation between morphologic appearance on computed tomography (CT) and histologic findings of CRLM after preoperative chemotherapy.

METHODS

We examined 47 patients who had undergone a first hepatic resection for CRLM after preoperative chemotherapy and had received contrast-enhanced CT scans. We assessed the morphologic appearance of the overall attenuation based on metastases changing from heterogeneous to mixed and homogenous lesions, the tumor-liver interface, and the peripheral rim enhancement on CT. Histologic parameters included usual necrosis (UN), infarct-like necrosis (ILN), three-zonal change, dangerous halo, mucous lake, shape of ILN, dominant type of necrosis, and presence of viable tumor cells. The relationship between morphologic appearance and histologic findings was evaluated.

RESULTS

CT overall attenuation revealed that UN predominance was more common in the heterogeneous group than in the mixed and homogeneous groups (P = 0.011). The frequency of ILN increased sequentially from ill-defined to variable and sharp at the tumor-liver interface (P = 0.038), and the frequency of UN decreased sequentially from present to partially resolved and completely resolved in the peripheral rim enhancement (P = 0.023). The histologic presence of viable tumor cells was closely associated with the tumor-liver interface (P = 0.0003) and the peripheral rim enhancement (P = 0.004).

CONCLUSIONS

CT morphologic appearance of CRLM after preoperative chemotherapy is correlated with histologic findings regarding necrosis.

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

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Impact of homogeneous pathologic response to preoperative chemotherapy in patients with multiple colorectal liver metastases

AIM

To analyze the homogeneity of pathologic response to preoperative chemotherapy (PRPC) after chemotherapy in patients with multiple liver metastases (LM).

METHODS

From September 2011 to August 2014, patients with at least two LM undergoing preoperative chemotherapy prior to resection were included in this retrospective, single-center study. The endpoints were PRPC homogeneity (according to both the Rubbia-Brandt and MD Anderson classifications), the impact of PRPC on the MDT decision, factors associated with homogeneous PRPC and overall survival of patients with vs. without homogeneous PRPC.

RESULTS

seventy-three patients with a total of 88 liver resections (including 15 two-stage procedures) were included in the study. The homogeneous PRPC rate was 55% according to the Rubbia-Brandt classification and 53% according to the MD Anderson classification. The MDT decision was modified by the PRPC in only 2.7% of patients (n = 2).

CONCLUSION

The PRPC was homogeneous in only one half of patients and had very little influence on the MDT decision.

An Overview of the Current Management of Bilobar Colorectal Liver Metastases

Bilobar colorectal liver metastases (BCRLM) present a challenging scenario for liver surgeons globally. The following article aims to provide an overview of the different strategies which may be utilised in order to successfully manage advanced BCRLM.

International consensus guidelines for scoring the histopathological growth patterns of liver metastasis

Background:

Liver metastases present with distinct histopathological growth patterns (HGPs), including the desmoplastic, pushing and replacement HGPs and two rarer HGPs. The HGPs are defined owing to the distinct interface between the cancer cells and the adjacent normal liver parenchyma that is present in each pattern and can be scored from standard haematoxylin-and-eosin-stained (H&E) tissue sections. The current study provides consensus guidelines for scoring these HGPs.

Methods:

Guidelines for defining the HGPs were established by a large international team. To assess the validity of these guidelines, 12 independent observers scored a set of 159 liver metastases and interobserver variability was measured. In an independent cohort of 374 patients with colorectal liver metastases (CRCLM), the impact of HGPs on overall survival after hepatectomy was determined.

Results:

Good-to-excellent correlations (intraclass correlation coefficient >0.5) with the gold standard were obtained for the assessment of the replacement HGP and desmoplastic HGP. Overall survival was significantly superior in the desmoplastic HGP subgroup compared with the replacement or pushing HGP subgroup (P=0.006).

Conclusions:

The current guidelines allow for reproducible determination of liver metastasis HGPs. As HGPs impact overall survival after surgery for CRCLM, they may serve as a novel biomarker for individualised therapies.

Reversibility of chemotherapy-related liver injury

BACKGROUND & AIMS

Chemotherapy-associated liver injury (CALI) increases the risk of liver resection and may prejudice further surgery and chemotherapy. The reversibility of CALI is therefore important; however, no data concerning this are available. This study aimed to retrospectively analyze the reversibility of CALI in patients undergoing liver resection for colorectal metastases.

METHODS

All resections of colorectal liver metastases after oxaliplatin and/or irinotecan-based chemotherapy were included. First, liver resections were stratified by time between end of chemotherapy and hepatectomy and several possible cut-off values tested. CALI prevalence in various groups was compared. Second, CALI in the two specimens from each patient who had undergone repeat liver resections without interval chemotherapy were compared.

RESULTS

Overall, 524 liver resections in 429 patients were analyzed. The median interval chemotherapy-surgery was 56days (15-1264). CALI prevalence did not differ significantly between groups with a chemotherapy-surgery interval <270days. Grade 2-3 sinusoidal dilatation (SOS, 19.4% vs. 40.0%, p=0.022) and nodular regenerative hyperplasia (NRH, 6.5% vs. 20.1%, p=0.063) occurred less frequently in patients with an interval >270days (n=31); prevalence of steatosis and steatohepatitis was similar in all groups. A chemotherapy-surgery interval >270days was an independent protector against Grade 2-3 SOS (p=0.009). Forty-seven patients had repeat liver resection without interval chemotherapy. CALI differed between surgeries only for a chemotherapy-surgery interval >270days (n=15), Grade 2-3 SOS having regressed in 4/5 patients and NRH in 7/8; whereas steatosis and steatohepatitis had persisted.

CONCLUSIONS

CALI persists for a long time after chemotherapy. SOS and NRH regress only after nine months without chemotherapy, whereas steatosis and steatohepatitis persist.

LAY SUMMARY

The patients affected by colorectal liver metastases often receive chemotherapy before liver resection, but chemotherapy causes liver injuries that may increase operative risks and reduce tolerance to further chemotherapy. The authors analyzed the reversibility of the liver injuries after the chemotherapy interruption. Liver injuries persist for a long time after chemotherapy. Sinusoidal dilatation and nodular regenerative hyperplasia regress only nine months after the end of chemotherapy, whereas steatosis and steatohepatitis persist even after this long interval.

3T diffusion-weighted MRI in the response assessment of colorectal liver metastases after chemotherapy: Correlation between ADC value and histological tumour regression grading

PURPOSE

The purpose of the study was to correlate the apparent diffusion coefficient (ADC) values of diffusion-weighted MR imaging (DW-MRI) by 3T device with the histological tumour regression grading (TRG) analysis of colorectal liver metastases after preoperative chemotherapy.

MATERIALS AND METHODS

Our study included thirty-five patients with colorectal liver metastases who had undergone MRI by 3T device (GE DISCOVERY MR750; GE Healthcare) after preoperative chemotherapy. DW-MRI was performed using a single-shot spin-echo echo-planar sequence with multiple b-values (0, 150, 500, 1000, 1500s/mm²), thus obtaining an ADC map. For each liver lesion (more than 1cm in diameter) the fitted ADC values were calculated by two radiologists in conference and three ROIs were drawn: around the entire tumour (ADC_e), at the tumour periphery (ADC_p) and at the tumour center (ADC_c). All ADC values were correlated with histopathological findings after surgery. Hepatic metastases were pathologically classified into five groups on the basis of TRG. Statistical analysis was performed on a per-lesion basis utilizing the one-way analysis of variance (ANOVA). This retrospective study was approved by our institutional review board; written informed consent was obtained from all patients.

RESULTS

A total of 106 colorectal liver metastases were included for image analysis. TRG1, TRG2, TRG3, TRG4 and TRG5 were observed in 4, 14, 36, 35 and 17 lesions, respectively. ADC_e and ADC_p values were significantly higher in lesions classified as TRG1 (2.40±0.12×10^-9m²/s and 2.28±0.26×10^-9m²/s, respectively) and as TRG2 (1.40±0.31×10^-9m²/s and 1.44±0.35×10^-9m²/s), compared to TRG3 (1.16±0.13×10^-9m²/s and 1.01±0.18×10^-9m²/s), TRG4 (1.10±0.26×10^-9m²/s and 0.97±0.24×10^-9m²/s), and TRG5 (0.93±0.17×10^-9m²/s and 0.82±0.28×10^-9m²/s). ADC_e, ADC_p and ADC_c values were significantly different in TRG classes (p<0.0001). Statistical correlations were found between the ADC_e, ADC_p, ADC_c values and the TRG classes (Spearman correlation coefficient were -0.568, -0.542 and -0.554, respectively).

CONCLUSION

Our study showed a significant correlation between ADC values of 3T DW-MRI and histological TRG of colorectal liver metastases after preoperative chemotherapy.

Significance of R1 Resection for Advanced Colorectal Liver Metastases in the Era of Modern Effective Chemotherapy

BACKGROUND

The prognosis impact of positive margins after resection of colorectal liver metastases (CLM) in patients treated with modern effective chemotherapy has not been elucidated. The objective was to compare oncologic outcomes after R0 and R1 resections in the era of modern effective chemotherapy.

METHODS

Between 1999 and 2010, all consecutive patients undergoing liver resection for CLM were analyzed retrospectively. Patients with extrahepatic metastases, macroscopic residual tumor, treated with combined radiofrequency, or not treated with chemotherapy were excluded. Survival and recurrence after R0 (tumor-free margin >0 mm) and R1 resections were analyzed.

RESULTS

Among 466 patients undergoing hepatectomy for CLM, 191 were eligible. Of them, 164 (86 %) received preoperative chemotherapy and 105 (55 %) received postoperative chemotherapy. R1 resection (10 %) was comparable in patients treated or not by preoperative chemotherapy. R1 status was associated with more intrahepatic recurrences. Overall survival (OS) (44 vs. 61 %; p = 0.047) and disease-free survival (DFS) (8 vs. 26 %; p = 0.082) were lower in patients after R1 compared to R0 resection (32 months of median follow-up). Preoperative chemotherapy and major hepatectomy were prognostic factors of survival, whereas postoperative chemotherapy was a protective factor from recurrences. In patients treated with preoperative chemotherapy, OS and DFS were similar between R1 and R0 resections (40 vs. 55 %, p = 0.104 and 9 vs. 22 %, p = 0.174, respectively).

CONCLUSION

In the era of modern effective chemotherapy, R1 resection leads to more intrahepatic recurrences but did not affect OS in selected patient responders to neoadjuvant chemotherapy. Postoperative chemotherapy protects from recurrences whatever the margin resection status.

Management of patients with colorectal liver metastasis in eleven questions and answers

INTRODUCTION

Colorectal liver metastasis (CRLM) is the most frequent indication for liver resection in many centers. Recent improvements in oncology, surgery, interventional radiology, pathology and anesthesiology allow curative treatment in a larger proportion of patients with CRLM. Areas covered: We illustrate the various aspects of the management of CRLM through 11 questions that summarize the topic, from the current obtained survival to future perspectives such as transplantation. The limits of a curative treatment are also presented from different angles, such as the benefits of pathology, the surgical options for extreme resections, the available chemotherapies and their efficacy, or the non-surgical ablative treatments. Expert commentary: Given the increasing therapeutic possibilities, we strengthen the importance to analyze the situation of each patient with CRLM in a dedicated multidisciplinary team, in order to offer the best individualized treatment combination.

Clinical risk scores in the current era of neoadjuvant chemotherapy for colorectal liver metastases

BACKGROUND

Clinical risk scores (CRS) within the context of neoadjuvant chemotherapy for colorectal liver metastases (CRLM) has not been validated. The predictive value of clinical risk scoring in patients administered neoadjuvant chemotherapy prior to liver surgery for CRLM is evaluated.

METHODS

A prospective database over a 15-year period (April 1999 to March 2014) was analysed. We identified two groups: A, neoadjuvant chemotherapy prior to CRLM surgery; and B, no neoadjuvant chemotherapy.

RESULTS

Overall median survival in groups A and B were 36 (2-137) months and 33 (2-137) months. In group A, nodal status, size, number of metastases and carcinoembryonic antigen levels were not found to be independent predictors of overall survival (OS). However, patients with a shorter disease-free interval of less than 12 months had an increased OS (P = 0.0001). Multivariate analysis of high- and low-risk scores compared against survival in group B (P < 0.05) confirms the applicability of the scoring system in traditional settings.

CONCLUSION

Traditional CRS are not a prognostic predictive tool when applied to patients receiving neoadjuvant chemotherapy for CRLM. Disease-free interval may be one independent variable for use in future risk score systems specifically developed for the neoadjuvant chemotherapy era.

Parenchymal-sparing liver surgery in patients with colorectal carcinoma liver metastases

Liver resection is the treatment of choice for patients with colorectal liver metastases (CLM). However, major resections are often required to achieve R0 resection, which are associated with substantial rates of morbidity and mortality. Maximizing the amount of residual liver gained increasing significance in modern liver surgery due to the high incidence of chemotherapy-associated parenchymal injury. This fact, along with the progressive expansion of resectability criteria, has led to the development of a surgical philosophy known as "parenchymal-sparing liver surgery" (PSLS). This philosophy includes a variety of resection strategies, either performed alone or in combination with ablative therapies. A profound knowledge of liver anatomy and expert intraoperative ultrasound skills are required to perform PSLS appropriately and safely. There is a clear trend toward PSLS in hepatobiliary centers worldwide as current evidence indicates that tumor biology is the most important predictor of intrahepatic recurrence and survival, rather than the extent of a negative resection margin. Tumor removal avoiding the unnecessary sacrifice of functional parenchyma has been associated with less surgical stress, fewer postoperative complications, uncompromised cancer-related outcomes and higher feasibility of future resections. The increasing evidence supporting PSLS prompts its consideration as the gold-standard surgical approach for CLM.

Clinical practice guidelines for the management of metastatic colorectal cancer: a consensus statement of the Hellenic Society of Medical Oncologists (HeSMO)

There is discrepancy and failure to adhere to current international guidelines for the management of metastatic colorectal cancer (CRC) in hospitals in Greece and Cyprus. The aim of the present document is to provide a consensus on the multidisciplinary management of metastastic CRC, considering both special characteristics of our Healthcare System and international guidelines. Following discussion and online communication among the members of an executive team chosen by the Hellenic Society of Medical Oncology (HeSMO), a consensus for metastastic CRC disease was developed. Statements were subjected to the Delphi methodology on two voting rounds by invited multidisciplinary international experts on CRC. Statements reaching level of agreement by ≥80% were considered as having achieved large consensus, whereas statements reaching 60-80% moderate consensus. One hundred and nine statements were developed. Ninety experts voted for those statements. The median rate of abstain per statement was 18.5% (range: 0-54%). In the end of the process, all statements achieved a large consensus. The importance of centralization, care by a multidisciplinary team, adherence to guidelines, and personalization is emphasized. R0 resection is the only intervention that may offer substantial improvement in the oncological outcomes.

RAS Mutation Predicts Positive Resection Margins and Narrower Resection Margins in Patients Undergoing Resection of Colorectal Liver Metastases

BACKGROUND

In patients undergoing resection of colorectal liver metastases (CLM), resection margin status is a significant predictor of survival, particularly in patients with suboptimal response to preoperative therapy. RAS mutations have been linked to more invasive and migratory tumor biology and poor response to modern chemotherapy.

OBJECTIVE

The aim of this study was to evaluate the relationship between RAS mutation and resection margin status in patients undergoing resection of CLM.

METHODS

Patients who underwent curative resection of CLM from 2005 to 2013 with known RAS mutation status were identified from a prospectively maintained database. A positive margin was defined as tumor cells <1 mm from the parenchymal transection line.

RESULTS

The study included 633 patients, of whom 229 (36.2 %) had mutant RAS. The positive margin rate was 11.4 % (26/229) for mutant RAS and 5.4 % (22/404) for wild-type RAS (p = 0.007). In multivariate analysis, the only factors associated with a positive margin were RAS mutation (hazard ratio [HR] 2.439; p = 0.005) and carcinoembryonic antigen level 4.5 ng/mL or greater (HR 2.060; p = 0.026). Among patients presenting with liver-first recurrence during follow-up, those with mutant RAS had narrower margins at initial CLM resection (median 4 mm vs. 7 mm; p = 0.031). A positive margin (HR 3.360; p < 0.001) and RAS mutation (HR 1.629; p = 0.044) were independently associated with worse overall survival.

CONCLUSION

RAS mutations are associated with positive margins in patients undergoing resection of CLM. Tumors with RAS mutation should prompt careful efforts to achieve negative resection margins.

Treatment strategies for colorectal carcinoma with synchronous liver metastases: Which way to go?

AIM: To offer an up-to-date review of all available treatment strategies for patients with synchronous colorectal liver metastases (CLM).

METHODS: A comprehensive literature search was performed to identify articles related to the management of patients with synchronous CLM. A search of the electronic databases PubMed, MEDLINE, and Google Scholar was conducted in September 2014. The following search terms were used: synchronous colorectal liver metastases, surgery, stage IV colorectal cancer, liver-first approach, and up-front hepatectomy. These terms were employed in various combinations to maximize the search. Only articles written in English were included. Particular attention was devoted to studies and review articles that were published within the last six years (2009-2014). Additional searches of the cited references from primary articles were performed to further improve the review. The full texts of all relevant articles were accessed by two independent reviewers.

RESULTS: Poor long-term outcomes of patients with synchronous CLM managed by a traditional treatment strategy have led to questions about the timing and sequence of possible therapeutic interventions. Thus, alternative paradigms called reverse strategies have been proposed. Presently, there are four treatment strategies available: (1) primary first approach (or traditional approach) comprises resection of the primary colorectal tumor followed by chemotherapy; subsequent liver resection is performed 3-6 mo after colorectal resection (provided that CLM are still resectable); (2) simultaneous resection of the primary colorectal tumor and CLM during a single operation presents intriguing options for a highly select group of patients, which can be associated with significant postoperative morbidity; (3) liver-first (or chemotherapy-first) approach comprises preoperative chemotherapy (3-6 cycles) followed by liver resection, adjuvant chemotherapy, and resection of the primary colorectal tumor (it is best suited for patients with asymptomatic primary tumors and initially unresectable or marginally resectable CLM); and (4) up-front hepatectomy (or “true” liver-first approach) includes liver resection followed by adjuvant chemotherapy, colorectal resection, and adjuvant chemotherapy (strategy can be offered to patients with asymptomatic primary tumors and initially resectable CLM).

CONCLUSION: None of the aforementioned strategies appears inferior. It is necessary to establish individual treatment plans in multidisciplinary team meetings through careful appraisal of all strategies.

Proposal for novel histological findings of colorectal liver metastases with preoperative chemotherapy

This study aimed to clarify the histological characteristics related to preoperative chemotherapy for colorectal liver metastases (CRLM). Sixty-three patients with CRLM were divided into two groups: CRLM with chemotherapy (41 cases, group A) and CRLM without chemotherapy (22 cases; surgical treatment alone, group S) to identify the histological differences associated with chemotherapy. In addition, we investigated the effects of combination chemotherapy on the histology of metastatic lesions. Infarct-like necrosis (ILN), three-zonal changes, and cholesterol clefts were more frequent in group A than in group S (P < 0.05). ILN and three-zonal changes were more common in the 5-FU with leucovorin and oxaliplatin (FOLFOX), or 5-FU with leucovorin and irinotecan (FOLFIRI) with or without additional bevacizumab groups than in group S (P < 0.05). Cholesterol clefts in the FOLFOX or FOLFIRI with bevacizumab group and foamy macrophages in the FOLFOX or FOLFIRI group were more common than in group S (P < 0.05). Cases with more than three of the four histological findings--i.e. ILN, three-zonal changes, cholesterol clefts, and foamy macrophages--were more frequent in the FOLFOX or FOLFIRI with or without additional bevacizumab groups than in group S (P < 0.05). We showed histological findings for every representative chemotherapy regimen for CRLM to clarify the effects of preoperative chemotherapy.

Characteristics suggestive of focal Fatty sparing from liver malignancy on ultrasound in liver screening

OBJECTIVE

The objective of this study was to determine whether there are ultrasound characteristics that can be used to differentiate focal fatty sparing (FFS) from hepatocellular carcinoma and other liver malignancies in liver screening.

METHODS

Data of patients with FFS found at ultrasound were reviewed, 136 patients with FFS were included, and 112 patients with hepatocellular carcinoma and 65 patients with liver metastatic tumor (173 tumors) were selected as control group. Ultrasound and color Doppler characteristics of FFS and liver malignancies were studied. Some characteristics drawn from this study were used as reference to validate the liver malignancies and FFS, and sensitivity, specificity, and positive and negative predictive values were calculated.

RESULTS

Hyperechogenicity, isoechogenicity, heterogeneous echotexture, posterior acoustic shadowing, halo, hypervasculature presented exclusively in liver malignancies, posterior acoustic enhancement presented predominantly in liver malignancies, irregularly shaped morphology presented exclusively in FFS, arterial velocity, and maximal size of liver malignancies were significantly higher than those of FFS (P < 0.001). Halo presented in 109 of 285 liver malignancies (38.2%), but was absent in FFS (P < 0.001). The overall sensitivity, specificity, and positive and negative predictive values were 94.38%, 90.44%, and 95.39% and 88.49%, respectively.

CONCLUSIONS

Combination of hyperechogenicity, isoechogenicity, heterogeneous echotexture, posterior acoustic shadowing, posterior acoustic enhancement, halo appearance, and hypervascularity with high-speed artery has high sensitivity, specificity, and positive and negative predictive values for distinguishing liver malignancy and FFS.

Feasibility and survival of 2-stage hepatectomy for colorectal metastases: definition of a simple and early clinicopathologic predicting score

INTRODUCTION

Bilobar colorectal metastases may be treated by a 2-stage surgical strategy. The risk of drop out after the first stage hepatectomy remains high and is associated with a nearly zero survival rate at 3 years. Our goal was to evaluate the factors predictive of the feasibility of the strategy and long-term survival, based on simple clinical and histologic features obtained from the first stage specimen.

PATIENTS AND METHODS

Patients who underwent a first stage hepatectomy with curative intent were included. Preoperative clinical parameters and histologic features of the primary neoplasm and metastases obtained at the first stage hepatectomy were analyzed and compared between patients who did or did not undergo the second stage operation. A group of comparable patients treated only by chemotherapy was used as a control group.

RESULTS

The feasibility rate of this 2-stage resection was 76% (38/50 patients). Median survival was greater in patients treated with chemotherapy alone than for those who failed the second stage. A clinicopathologic score including male sex, segment 1 metastasis, need for >3 resection(s)/radiofrequency ablation(s), vascular invasion in the primary, need for change in type of chemotherapy, and microscopic biliary invasion by the metastasis was predictive of feasibility of the second stage and disease-free survival in patients achieving the second stage.

CONCLUSION

Combining preoperative clinical parameters with pathologic features of the primary and the metastatic lesions obtained during first stage hepatectomy predicted accurately patients who failed the second stage, and the long-term outcomes. Considering both clinical and pathologic parameters may help to define the best oncologic strategy by choosing between an exclusive chemotherapeutic or a surgical strategy.

Reversal of attachment to or invasion of major intrahepatic vessels by colorectal liver metastases according to prehepatectomy chemotherapy regimen

BACKGROUND

Tumor reduction by present-day prehepatectomy chemotherapy can render initially unresectable disease resectable. However, little is known about whether effects on liver metastases with radiologically defined "attachment to or invasion of" major intrahepatic vessels differ between chemotherapy regimens with or without monoclonal antibodies. We compared histologically the relationships between liver tumors and major intrahepatic vessels after chemotherapy according to regimens used to treat colorectal liver metastasis.

METHODS

In 38 patients who underwent chemotherapy and hepatectomy with pretreatment images showing metastases attached to or invading major intrahepatic vessels, 62 metastases showed attachment to or invasion of 88 vessels. After resection, attachment, invasion, and separation were determined histopathologically in resected specimens.

RESULTS

Thirteen patients received cytotoxic drug combinations alone, whereas 25 were treated with regimens including a monoclonal antibody (bevacizumab in 15 and cetuximab in 10). By imaging, 16% (5/32) of vessels in patients receiving cytotoxic drugs alone, 23% (8/35) of vessels in those also receiving bevacizumab, and 48% (10/21) of vessels in those also receiving cetuximab showed detachment after chemotherapy (P = .015 for cetuximab versus cytotoxic and P = .039 for cetuximab versus bevacizumab). Excluding 8 vessels not evaluated histologically, 23 of 31 vessels in the cytotoxic group remained attached or invaded, as did 16 of 29 in the bevacizumab group and 8 of 20 vessels in the cetuximab group (P = .05 versus cytotoxic).

CONCLUSION

Prehepatectomy chemotherapy regimens including monoclonal antibodies, particularly anti-epidermal growth factor receptor antibodies, eradicated attachment or invasion between vessels and metastases more frequently. Individualized strategies for prehepatectomy chemotherapy based on intrahepatic location of metastases may offer advantages according to proximity of the metastases to the major intrahepatic vessels.

Early recurrence after liver resection for colorectal metastases: risk factors, prognosis, and treatment. A LiverMetSurvey-based study of 6,025 patients

PURPOSE

The aims of this study were to assess the risk of early recurrence after liver resection for colorectal metastases (CRLM) and its prognostic value; identify early recurrence predictive factors; clarify the effect of perioperative chemotherapy on its occurrence; and elucidate the best early recurrence management.

METHODS

Patients of the LiverMetSurvey registry who underwent complete liver resection (R0/R1) between 1998 and 2009 were reviewed. Early recurrence was defined as any recurrence that occurred within 6 months after resection.

RESULTS

A total of 6,025 patients were included; 2,734 (45.4 %) had recurrence, including 639 (10.6 %) early recurrences. Early recurrence was mainly hepatic (59.5 vs. 54.4 % for late recurrences; p = 0.023). Independent risk factors of early recurrence were: T3-4 primary tumor (p = 0.0002); synchronous CRLM (p = 0.0001); >3 CRLM (p < 0.0001); 0-mm margin liver resection (p = 0.003); and associated intraoperative radiofrequency ablation (p = 0.0005). Response to preoperative chemotherapy (complete/partial) and administration of adjuvant chemotherapy reduced early recurrence risk (p = 0.003 and p < 0.0001, respectively). Intraoperative ultrasonography reduced hepatic early recurrence rate (p = 0.025). Early recurrence negatively affected prognosis: 5-year survival 26.9 versus 49.4 % for the late recurrence group (p < 0.0001, median follow-up 34.4 months). Overall, 234 (36.6 %) patients with early recurrence underwent re-resection. These patients had survival rates higher than non-re-resected patients (5-year survival 47.2 vs. 8.9 %; p < 0.0001) and similar to re-resected patients for late recurrence (48.7 %). Chemotherapy before early recurrence resection improved later survival (5-year survival 61.5 vs. 43.7 %; p = 0.028).

CONCLUSIONS

Early recurrence risk is enhanced for extensive disease after poor preoperative disease control and inadequate surgical treatment, but is reduced after adjuvant chemotherapy. Although early recurrence negatively affects prognosis, re-resection may restore better survival. Chemotherapy before early recurrence resection is advocated.

Locoregional surgical and interventional therapies for advanced colorectal cancer liver metastases: expert consensus statements

Selection of the optimal surgical and interventional therapies for advanced colorectal cancer liver metastases (CRLM) requires multidisciplinary discussion of treatment strategies early in the trajectory of the individual patient's care. This paper reports on expert consensus on locoregional and interventional therapies for the treatment of advanced CRLM. Resection remains the reference treatment for patients with bilateral CRLM and synchronous presentation of primary and metastatic cancer. Patients with oligonodular bilateral CRLM may be candidates for one-stage multiple segmentectomies; two-stage resection with or without portal vein embolization may allow complete resection in patients with more advanced disease. After downsizing with preoperative systemic and/or regional therapy, curative-intent hepatectomy requires resection of all initial and currently known sites of disease; debulking procedures are not recommended. Many patients with synchronous primary disease and CRLM can safely undergo simultaneous resection of all disease. Staged resections should be considered for patients in whom the volume of the future liver remnant is anticipated to be marginal or inadequate, who have significant medical comorbid condition(s), or in whom extensive resections are required for the primary cancer and/or CRLM. Priority for liver-first or primary-first resection should depend on primary tumour-related symptoms or concern for the progression of marginally resectable CRLM during treatment of the primary disease. Chemotherapy delivered by hepatic arterial infusion represents a valid option in patients with liver-only disease, although it is best delivered in experienced centres. Ablation strategies are not recommended as first-line treatments for resectable CRLM alone or in combination with resection because of high local failure rates and limitations related to tumour size, multiplicity and intrahepatic location.