Improving resectability of hepatic colorectal metastases: expert consensus statement

Improved performance and consistency of deep learning 3D liver segmentation with heterogeneous cancer stages in magnetic resonance imaging

PURPOSE

Accurate liver segmentation is key for volumetry assessment to guide treatment decisions. Moreover, it is an important pre-processing step for cancer detection algorithms. Liver segmentation can be especially challenging in patients with cancer-related tissue changes and shape deformation. The aim of this study was to assess the ability of state-of-the-art deep learning 3D liver segmentation algorithms to generalize across all different Barcelona Clinic Liver Cancer (BCLC) liver cancer stages.

METHODS

This retrospective study, included patients from an institutional database that had arterial-phase T1-weighted magnetic resonance images with corresponding manual liver segmentations. The data was split into 70/15/15% for training/validation/testing each proportionally equal across BCLC stages. Two 3D convolutional neural networks were trained using identical U-net-derived architectures with equal sized training datasets: one spanning all BCLC stages ("All-Stage-Net": AS-Net), and one limited to early and intermediate BCLC stages ("Early-Intermediate-Stage-Net": EIS-Net). Segmentation accuracy was evaluated by the Dice Similarity Coefficient (DSC) on a dataset spanning all BCLC stages and a Wilcoxon signed-rank test was used for pairwise comparisons.

RESULTS

219 subjects met the inclusion criteria (170 males, 49 females, 62.8±9.1 years) from all BCLC stages. Both networks were trained using 129 subjects: AS-Net training comprised 19, 74, 18, 8, and 10 BCLC 0, A, B, C, and D patients, respectively; EIS-Net training comprised 21, 86, and 22 BCLC 0, A, and B patients, respectively. DSCs (mean±SD) were 0.954±0.018 and 0.946±0.032 for AS-Net and EIS-Net (p<0.001), respectively. The AS-Net 0.956±0.014 significantly outperformed the EIS-Net 0.941±0.038 on advanced BCLC stages (p<0.001) and yielded similarly good segmentation performance on early and intermediate stages (AS-Net: 0.952±0.021; EIS-Net: 0.949±0.027; p = 0.107).

CONCLUSION

To ensure robust segmentation performance across cancer stages that is independent of liver shape deformation and tumor burden, it is critical to train deep learning models on heterogeneous imaging data spanning all BCLC stages.

Hepatectomy Followed by mFOLFOX6 Versus Hepatectomy Alone for Liver-Only Metastatic Colorectal Cancer (JCOG0603): A Phase II or III Randomized Controlled Trial

PURPOSE

Adjuvant chemotherapy after hepatectomy is controversial in liver-only metastatic colorectal cancer (CRC). We conducted a randomized controlled trial to examine if adjuvant modified infusional fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) is superior to hepatectomy alone for liver-only metastasis from CRC.

PATIENTS AND METHODS

In this phase II or III trial (JCOG0603), patients age 20-75 years with confirmed CRC and an unlimited number of liver metastatic lesions were randomly assigned to hepatectomy alone or 12 courses of adjuvant mFOLFOX6 after hepatectomy. The primary end point of phase III was disease-free survival (DFS) in intention-to-treat analysis.

RESULTS

Between March 2007 and January 2019, 300 patients were randomly assigned to hepatectomy alone (149 patients) or hepatectomy followed by chemotherapy (151 patients). At the third interim analysis of phase III with median follow-up of 53.6 months, the trial was terminated early according to the protocol because DFS was significantly longer in patients treated with hepatectomy followed by chemotherapy. With median follow-up of 59.2 months, the updated 5-year DFS was 38.7% (95% CI, 30.4 to 46.8) for hepatectomy alone compared with 49.8% (95% CI, 41.0 to 58.0) for chemotherapy (hazard ratio, 0.67; 95% CI, 0.50 to 0.92; one-sided P = .006). However, the updated 5-year overall survival (OS) was 83.1% (95% CI, 74.9 to 88.9) with hepatectomy alone and 71.2% (95% CI, 61.7 to 78.8) with hepatectomy followed by chemotherapy. In the chemotherapy arm, the most common grade 3 or higher severe adverse event was neutropenia (50% of patients), followed by sensory neuropathy (10%) and allergic reaction (4%). One patient died of unknown cause after three courses of mFOLFOX6 administration.

CONCLUSION

DFS did not correlate with OS for liver-only metastatic CRC. Adjuvant chemotherapy with mFOLFOX6 improves DFS among patients treated with hepatectomy for CRC liver metastasis. It remains unclear whether chemotherapy improves OS.

Radiation Lobectomy: An Overview of Concept and Applications, Technical Considerations, Outcomes

Surgical resection has long been considered curative for patients with early-stage hepatocellular carcinoma (HCC). However, inadequate future liver remnant (FLR) renders many patients not amenable to surgery. Recently, lobar administration of yttrium-90 (Y90) radioembolization has been utilized to induce FLR hypertrophy while providing disease control, eventually facilitating resection in patients with hepatic malignancy. This has been termed "radiation lobectomy (RL)." The concept is evolving, with modified approaches combining RL and high-dose curative-intent radioembolization (radiation segmentectomy) to achieve tumor ablation. This article provides an overview of the concept and applications of RL, including technical considerations and outcomes in patients with hepatic malignancies.

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

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

Pragmatic use of short-course radiotherapy, chemotherapy and surgery for stage IV rectal cancer with locally advanced or symptomatic primary tumours

INTRODUCTION

We assessed management of patients with de novo metastatic rectal cancer, referred for radiotherapy to the rectum, who were candidates for short-course radiotherapy (SCRT) and chemotherapy, followed by resection of all disease. We assessed surgical outcomes, overall survival (OS) and progression-free survival (PFS).

METHODS

Retrospective review of patients meeting criteria: (i) treatment with SCRT to rectum; (ii) locally advanced primary rectal cancer; and (iii) resectable distant metastases at diagnosis. Data were collected from charts, correspondence and electronic patient records. OS and PFS were calculated using the Kaplan-Meier method.

RESULTS

Between 2016 and 2020, 48 patients with stage IV rectal cancer at diagnosis were treated with SCRT. Only 15 patients (31%) had resectable metastatic disease and were intended for SCRT (25 Gy/5#), then chemotherapy, followed by resection of all sites of disease and are included in our study. 12 of the 15 surgical candidates (80%) had rectal surgery as planned, and 11 of the 15 (73%) had resection of the rectal primary and all metastatic disease. One patient had a pathological complete response (pCR), and 50% of surgical patients had a Mandard TRG of 1 or 2. Median PFS and OS for the 15 surgical candidates were 12.6 and 25.2 months, respectively, with a median FU of 21.2 months.

CONCLUSION

For this cohort of patients, our treatment paradigm is pragmatic and results in excellent pathological response. However, the effectiveness of this approach should be the subject of future prospective studies.

Biomarkers associated with survival and favourable outcome of radioembolization with yttrium-90 glass microspheres for colon cancer liver metastases: Single centre experience

OBJECTIVE

To determine the therapeutic effectiveness and safety of transarterial radioembolization (TARE) with Yttrium-90 in patients with colorectal cancer (CRC) liver metastases and to evaluate the prognostic value of different biomarkers.

MATERIAL AND METHODS

This prospective longitudinal study enrolled consecutive patients with CRC liver metastases treated with TARE between November 2015 and june 2020. The therapeutic response at three and six months (RECIST1.1 criteria) and the relationship of biomarkers with therapeutic response, by calculating objective tumor response rates (ORR) and disease control (DCR), and overall survival (OS) and progression-free (PFS).

RESULTS

Thirty TAREs were performed in 23 patients (mean age, 61.61 ± 9.13 years; 56.5% male). At three months, the objective response rate (ORR) was 16.7% and the disease control rate (DCR) 53.3%. At six months, the disease progressed in 80%. The ORR and DCR were significantly associated with age at diagnosis (P = 0.047), previous bevacizumab treatment (P = 0.008), pre-TARE haemoglobin (P = 0.008), NLR (P = 0.040), pre-TARE albumin (P = 0.012), pre-TARE ALT (P = 0.023) and tumour-absorbed dose > 115 Gy (P = 0.033). Median overall survival (OS) was 12 months (95% CI, 4.75-19.25 months) and median progression-free survival (PFS) 3 months (95% CI, 2.41-3.59). OS was significantly associated with primary tumour resection (P = 0.019), KRAS mutation (HR: 5.15; P = 0.024), pre-TARE haemoglobin (HR: 0.50; p = 0.009), pre-TARE NLR (HR: 1.65; P = 0.005) and PLR (HR: 1.01; P = 0.042).

CONCLUSION

TARE prognosis and therapeutic response were predicted by different biomarkers, ranging from biochemical parameters to tumour dosimetrics.

Comparison of nuclear imaging techniques and volumetric imaging for the prediction of postoperative mortality and liver failure in patients undergoing localized liver-directed treatments: a systematic review

Background/aims

Although volumetric imaging by computed tomography (CT) is the gold standard for preoperative assessment of the future liver remnant, nuclear imaging studies have shown promising data. This systematic review summarized the results from trials investigating volumetric and nuclear medicine imaging for the prediction of postoperative mortality and liver failure (LF).

Methods

MEDLINE and Web of Science were searched for papers investigating nuclear imaging methods for the prediction of postoperative clinical outcomes in patients undergoing local, liver-directed treatments. Only papers investigating both preoperative nuclear imaging and CT or magnetic resonance imaging (MR) for the prediction of postoperative mortality and/or LF were included.

Results

Twenty-five trials were qualified for this review. All trials but two used technetium-based tracers for the nuclear imaging examination. Four papers used MR imaging and the remaining used CT for the volumetric evaluation. Overall, the studies were heterogeneous both in terms of methodology and imaging technique. Of the thirteen studies reporting on postoperative mortality, most were descriptive without detailed diagnostic data. A few with detailed data found that nuclear imaging had better predictive value than volumetric imaging. Nineteen studies investigated the prediction of postoperative LF of which seven papers investigated the predictive value of both modalities in multivariable regression analysis. Two papers found that only nuclear imaging parameters were predictive of LF, one paper found that the CT parameter was predictive, and four papers found that combined nuclear and CT/MR imaging parameters were predictive of LF.

Conclusion

Both methodologies were useful in the preoperative assessment of patients scheduled for liver interventions, especially in combination, but nuclear imaging demonstrated better predictive value for postoperative mortality and LF in a few trials. The overall technical and methodological heterogeneity of the included studies complicates the ability to directly compare the clinical utility of the two imaging techniques.

Biomarkers associated with survival and favourable outcome of radioembolization with yttrium-90 glass microspheres for colon cancer liver metastases: Single centre experience

OBJETIVE

To determine the therapeutic effectiveness and safety of transarterial radioembolization (TARE) with Yttrium-90 in patients with colorectal cancer (CRC) liver metastases and to evaluate the prognostic value of different biomarkers.

MATERIAL AND METHODS

This prospective longitudinal study enrolled consecutive patients with CRC liver metastases treated with TARE between November 2015 and june 2020. The therapeutic response at three and six months (RECIST1.1 criteria) and the relationship of biomarkers with therapeutic response, by calculating objective tumor response rates (ORR) and disease control (DCR), and overall survival (OS) and progression-free (PFS).

RESULTS

Thirty TAREs were performed in 23 patients (mean age, 61,61±9,13 years; 56,5% male). At three months, the objective response rate (ORR) was 16,7% and the disease control rate (DCR) 53,3%. At six months, the disease progressed in 80%. The ORR and DCR were significantly associated with age at diagnosis (P=.047), previous bevacizumab treatment (P=.008), pre-TARE haemoglobin (P=.008), NLR (P=.040), pre-TARE albumin (P=.012), pre-TARE ALT (P=.023) and tumour-absorbed dose>115Gy (P=.033). Median overall survival (OS) was 12 months (95% CI, 4.75-19.25 months) and median progression-free survival (PFS) 3 months (95% CI, 2.41-3.59). OS was significantly associated with primary tumour resection (P=.019), KRAS mutation (HR: 5.15; P=.024), pre-TARE haemoglobin (HR: .50; p=.009), pre-TARE NLR (HR: 1.65; P=.005) and PLR (HR: 1.01; P=.042).

CONCLUSION

TARE prognosis and therapeutic response were predicted by different biomarkers, ranging from biochemical parameters to tumour dosimetrics.

Validation of the IMM classification in laparoscopic repeat liver resections for colorectal liver metastases

BACKGROUND

To validate the Institut Mutualiste Montsouris classification as a difficulty scoring system applicable to laparoscopic repeat liver resections and identify risk-factors of unexpected difficulty.

METHODS

From a prospectively collected database between 2000 and 2019, patients undergoing laparoscopic repeat liver resections were classified according to the Institut Mutualiste Montsouris classification. Doubly robust estimators (weighted regressions) were used to assess the effect of factors on intra- and postoperative outcomes and allowed for strong adjustment on age, body mass index, American Society of Anesthesiologists, carcinoembryonic antigen, number, and size of lesions. Unexpected difficulty was defined as a composite indicator which included substantial blood loss and/or substantial operative time and/or conversion.

RESULTS

Of 205 laparoscopic repeat liver resections patients, 87, 25, and 93 procedures were classified as grade 1, 2, and 3 laparoscopic repeat liver resections, respectively. After doubly robust adjustment, the IMM classification was associated with blood loss (Cohen f² 0.12; P = 0.001), operative time (Cohen f² 0.07; P = .001), and length of stay (Cohen f² 0.13; P = .001), as well as with the risk of both minor and severe complications (odd ratio = 2.94; 95% confidence interval: 2.06-4.20) and the chances of achieving textbook outcome (relative risk = 0.57; 95% confidence interval: 0.41-0.81). Independently from the Institut Mutualiste Montsouris classification, a first major hepatectomy (relative risk = 1.15, 95% confidence interval: 1.03-1.29) as well as sinusoidal obstruction syndrome (relative risk = 1.24, 95% confidence interval: 1.09-1.41) were independent risk factors of unexpected difficulty. A first major resection was associated with decreased chances of textbook outcome (relative risk = 0.53; 95% confidence interval: 0.33-0.85).

CONCLUSION

The Institut Mutualiste Montsouris classification is a valuable difficulty scoring system for laparoscopic repeat liver resections procedures, while previous major resection and presence of sinusoidal obstruction syndrome are likely to jeopardize the outcomes.

Optimization of the future remnant liver: review of the current strategies in Europe

Liver resection still represent the treatment of choice for liver malignancies, but in some cases inadequate future remnant liver (FRL) can lead to post hepatectomy liver failure (PHLF) that still represents the most common cause of death after hepatectomy. Several strategies in recent era have been developed in order to generate a compensatory hypertrophy of the FRL, reducing the risk of post hepatectomy liver failure. Portal vein embolization, portal vein ligation, and ALLPS are the most popular techniques historically adopted up to now. The liver venous deprivation and the radio-embolization are the most recent promising techniques. Despite even more precise tools to calculate the relationship among volume and function, such as scintigraphy with ^99mTc-mebrofenin (HBS), no consensus is still available to define which of the above mentioned augmentation strategy is more adequate in terms of kind of surgery, complexity of the pathology and quality of liver parenchyma. The aim of this article is to analyse these different strategies to achieve sufficient FRL.

The prognostic value of C-reactive protein and albumin in patients undergoing resection of colorectal liver metastases. A retrospective cohort study

BACKGROUND

The systemic inflammation-based Glasgow Prognostic Score (GPS) and modified GPS (mGPS), as measured by preoperative C-reactive protein (CRP) and albumin, correlate with poor survival in several cancers. This study evaluates the prognostic value of these scores in patients with colorectal liver metastases (CRLM).

METHODS

This retrospective study assessed the prognostic role of preoperatively measured GPS and mGPS in patients undergoing liver resection because of CRLM. Clinicopathological data were retrieved from local databases. The prognostic value of GPS and mGPS were compared and a Cox regression model was used to find independent predictors of overall survival.

RESULTS

In total, 849 consecutive patients between January 2005 and December 2015 were included. Patients with GPS 0 had a median survival of 70 months compared to 49 months in patients with GPS 1, and 27 months in patients with GPS 2. Multivariable analyses showed that GPS 1 (HR = 1.51, 95%CI [1.14-2.01]) and GPS 2 (HR = 2.78, 95%CI [1.79-4.31]), after correction for age >70 years (HR = 1.75 [1.36-2.26]), and extended resection (HR = 2.53, 95%CI[1.79-3.58]), were associated with poor overall survival.

CONCLUSION

A preoperative GPS is an independent prognostic factor in patients with CRLM, and appears to be a better prognostic tool than mGPS.

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) in colorectal liver metastases: review of the literature

The liver is considered as one of the most common sites of metastasis and a key determining factor of survival in patients with isolated colorectal liver metastasis (CRLM). For longer survival of patients, surgical resection is the only available option. Especially in CRLM bilobar patients, to achieve R0 resection, maintaining an adequate volume of the future liver remnant (FLR) is the main technical challenge to avoid post-hepatectomy liver failure (PHLF). As standard procedures in the treatment of patients with severe metastatic liver disease, techniques such as portal vein embolization/portal vein ligation (PVE/PVL) accompanied by two-stage hepatectomy (TSH) have been introduced. These methods, however, have drawbacks depending on the severity of the disease and the capacity of the patient to expand the liver remnant. Eventually, implementation of the novel ALPPS technique ignited excitement among the community of hepatobiliary surgeons because ALPPS challenged the idea of unrespectability and extended the limit of liver surgery and it was reported that FLR hypertrophy of up to 80% was induced in a shorter time than PVL or PVE. Nonetheless, ALPPS techniques caused serious concerns due to the associated high morbidity and mortality levels of up to 40% and 15% respectively, and PHLF and bile leak are critical morbidity- and mortality-related factors. Carefully establishing the associated risk factors of ALPPS has opened up a new dimension in the field of ALPPS technique for improved surgical outcome by carefully choosing patients. The benefit of ALPPS technique is enhanced when performed for young patients with very borderline remnant volume. Adopting ALPPS technical modifications such as middle hepatic vein preservation, surgical management of the hepatoduodenal ligament, the anterior approach and partial ALPPS may lead to the improvement of ALPPS surgical performance. Research findings to validate the translatability of ALPPS’ theoretical advantages into real survival benefits are scarce.

Pilot Clinical Trial of Perioperative Durvalumab and Tremelimumab in the Treatment of Resectable Colorectal Cancer Liver Metastases

PURPOSE

Despite the prognostic importance of immune infiltrate in colorectal cancer, immunotherapy has demonstrated limited clinical activity in refractory metastatic proficient mismatch-repair (pMMR) colorectal cancer. This study explores combining anti-CTLA-4 and an anti-PD-L1 therapy in the preoperative management of resectable colorectal cancer liver metastases with the intent to improve immune responses in this disease setting.

PATIENTS AND METHODS

Patients with resectable colorectal cancer liver-only metastases received one dose of tremelimumab and durvalumab preoperatively followed by single-agent durvalumab postoperatively. Primary objectives were to determine feasibility and safety.

RESULTS

A total of 24 patients were enrolled between November 2016 and November 2019. Twenty-three patients received treatment [21 pMMR and 2 deficient mismatch-repair (dMMR)] and subsequently 17 (74%; 95% CI: 53%-88%) underwent surgical resection. Grade 3/4 treatment-related immune toxicity and postoperative grade 3/4 toxicity were seen in 5/23 (22%; 95% CI: 10%-44%) and 2/17 (12%; 95% CI: 2%-38%) patients. The median relapse-free survival (RFS) was 9.7 (95% CI: 8.1-17.8) months, and overall survival was 24.5 (95% CI: 16.5-28.4) months. Four patients demonstrated complete pathologic response, two dMMR patients and two POLE mutation patients. Pre- and post-tumor tissue analysis by flow cytometry, immunofluorescence, and RNA sequencing revealed similar levels of T-cell infiltration, but did demonstrate evidence of CD8⁺ and CD4⁺ activation posttreatment. An increase in B-cell transcriptome signature and B-cell density was present in posttreatment samples from patients with prolonged RFS.

CONCLUSIONS

This study demonstrates the safety of neoadjuvant combination tremelimumab and durvalumab prior to colorectal cancer liver resection. Evidence for T- and B-cell activation following this therapy was seen in pMMR metastatic colorectal cancer.

Circular RNA in colorectal cancer

Circular RNA (circRNA) is a highly abundant type of single-stranded non-coding RNA. Novel research has discovered many roles of circRNA in colorectal cancer (CRC) including proliferation, metastasis and apoptosis. Furthermore, circRNAs also play a role in the development of drug resistance and have unique associations with tumour size, staging and overall survival in CRC that lend circRNAs the potential to serve as diagnostic and prognostic biomarkers. Among cancers worldwide, CRC ranks second in mortality and third in incidence. In order to have a better understanding of the influence of circRNA on CRC development and progression, this review summarizes the role of specific circRNAs in CRC and evaluates their potential value as therapeutic targets and biomarkers for CRC. We aim to provide insight in the development of therapy and clinical decision-making.

Yttrium-90 Hepatic Radioembolization for Advanced Chemorefractory Metastatic Colorectal Cancer: Survival Outcomes Based on Right- Versus Left-Sided Primary Tumor Location

BACKGROUND. Primary colon cancer location affects survival of patients with metastatic colorectal cancer (mCRC). Outcomes based on primary tumor location after salvage hepatic radioembolization with ⁹⁰Y resin microspheres are not well studied. OBJECTIVE. The objectives of this study are to assess the survival outcomes of patients with advanced chemorefractory mCRC treated with ⁹⁰Y radioembolization, as stratified by primary tumor location, and to explore potential factors that are predictive of survival. METHODS. A total of 99 patients who had progressive mCRC liver metastases while receiving systemic therapy and who were treated with ⁹⁰Y radioembolization at a single center were retrospectively analyzed. For 89 patients, tumor response on the first imaging follow-up examination (CT or MRI performed at a mean [± SD] of 1.9 ± 0.9 months after ⁹⁰Y radioembolization) was evaluated using RECIST. Overall survival (OS), OS after ⁹⁰Y radioembolization, and hepatic progression-free survival (PFS) were calculated using the Kaplan-Meier method. Outcomes and associations of outcomes with tumor response were compared between patients with left- and right-sided tumors. RESULTS. A total of 74 patients had left-sided colon cancer, and 25 patients had right-sided colon cancer. Median OS from the time of mCRC diagnosis was 37.2 months, median OS after ⁹⁰Y radioembolization was 5.8 months, and median hepatic PFS was 3.3 months. Based on RECIST, progressive disease on first imaging follow-up was observed in 38 patients (43%) after ⁹⁰Y radioembolization and was associated with shorter OS after ⁹⁰Y radioembolization compared with observation of disease control on first imaging follow-up (4.0 vs 10.5 months; p < .001). Patients with right-sided primary tumors showed decreased median OS after ⁹⁰Y radioembolization compared with patients with left-sided primary tumors (5.4 vs 6.2 months; p = .03). Right- and left-sided primary tumors showed no significant difference in RECIST tumor response, hepatic PFS, or extrahepatic disease progression (p > .05). Median survival after ⁹⁰Y radioembolization was significantly lower among patients with progressive disease than among those with disease control in the group with left-sided primary tumors (4.2 vs 13.9 months; p < .001); however, this finding was not observed in the group with right-sided primary tumors (3.3 vs 7.2 months; p = .05). CONCLUSION. Right-sided primary tumors were independently associated with decreased survival among patients with chemorefractory mCRC after ⁹⁰Y radioembolization, despite these patients having a similar RECIST tumor response, hepatic PFS, and extrahepatic disease progression compared with patients with left-sided primary tumors. CLINICAL IMPACT. Primary colon cancer location impacts outcomes after salvage ⁹⁰Y radioembolization and may help guide patient selection.

AMIGO2 as a novel indicator of liver metastasis in patients with colorectal cancer

Our previous study showed that adhesion molecule with immunoglobulin like domain 2 (AMIGO2) is a pivotal driver gene of liver metastasis via regulating tumor cell adhesion to liver endothelial cells in mouse models. The aim of the present study was to clarify the role of AMIGO2 in liver metastasis in patients the colorectal cancer (CRC). Two human CRC cell lines, Caco-2 (AMIGO2-low) and HCT116 (AMIGO2-high), were used in this study. AMIGO2-overexpressing Caco-2 and AMIGO2-knockdown HCT116 cells were generated by transfection with an AMIGO2 expression vector or AMIGO2 small interfering RNA, respectively. Cell proliferation, invasion and adhesion to human liver endothelial cells were examined in in vitro studies. Immunohistochemical analysis was also performed to evaluate the association between AMIGO2 expression and liver metastasis in patients with CRC. In vitro studies revealed that cell proliferation, invasion and adhesion to liver endothelial cells were accelerated by upregulation of AMIGO2 expression, but suppressed by downregulation of AMIGO2 expression in human CRC cells. Immunohistochemical analysis using clinical CRC specimens revealed that AMIGO2 expression was associated with the frequency of liver metastasis (P<0.01), but not that of pulmonary metastasis (P=0.611) and peritoneal dissemination (P=0.909). In addition, AMIGO2 expression levels in tumor cells were significantly higher in liver metastatic foci than primary lesions (P=0.012). In conclusion, the present results indicated that AMIGO2 expression may contribute to the formation of liver metastasis in CRC.

Portal vein embolization with N-butyl cyanoacrylate glue is superior to other materials: a systematic review and meta-analysis

OBJECTIVES

It remains uncertain which embolization material is best for portal vein embolization (PVE). We investigated the various materials for effectiveness in inducing future liver remnant (FLR) hypertrophy, technical and growth success rates, and complication and resection rates.

METHODS

A systematic review from 1998 to 2019 on embolization materials for PVE was performed on Pubmed, Embase, and Cochrane. FLR growth between the two most commonly used materials was compared in a random effects meta-analysis. In a separate analysis using local data (n = 52), n-butyl cyanoacrylate (NBCA) was compared with microparticles regarding costs, radiation dose, and procedure time.

RESULTS

In total, 2896 patients, 61.0 ± 4.0 years of age and 65% male, from 51 papers were included in the analysis. In 61% of the patients, either NBCA or microparticles were used for embolization. The remaining were treated with ethanol, gelfoam, or sclerosing agents. The FLR growth with NBCA was 49.1% ± 29.7 compared to 42.2% ± 40 with microparticles (p = 0.037). The growth success rate with NBCA vs microparticles was 95.3% vs 90.7% respectively (p < 0.001). There were no differences in major complications between NBCA and microparticles. In the local analysis, NBCA (n = 41) entailed shorter procedure time and reduced fluoroscopy time (p < 0.001), lower radiation exposure (p < 0.01), and lower material costs (p < 0.0001) than microparticles (n = 11).

CONCLUSION

PVE with NBCA seems to be the best choice when combining growth of the FLR, procedure time, radiation exposure, and costs.

KEY POINTS

• The meta-analysis shows that n-butyl cyanoacrylate (NBCA) is superior to microparticles regarding hypertrophy of the future liver remnant, 49.1% ± 29.7 vs 42.2% ± 40.0 (p = 0.037). • There is no significant difference in major complication rates for portal vein embolization using NBCA, 4% (24/681), compared with microparticles, 5% (25/494) (p > 0.05). • Local data shows a shorter procedure time, 215 vs 348 mins from arrival to departure at the interventional radiology unit, and fluoroscopy time, 43 vs 96 mins (p < 0.001), lower radiation dosage, 573 vs 1287 Gycm² (p < 0.01), and costs, €816 vs €4233 (p < 0.0001) for NBCA compared to microparticles.

Preoperative Portal Vein Embolization for Liver Resection: An updated meta-analysis

Background: Portal vein embolization (PVE) is performed before major liver resection to increase liver volume remnant, controversy remains on the adverse effect of PVE on liver tumor patients. The current study highlighted the effect of PVE on the degree of hypertrophy of future liver remnant (FLR) and summarized PVE-related complications, aiming to provide a guideline for surgeons.

Methods: A search of current published studies on PVE was performed. Meta-analysis was conducted to assess the effect of PVE on hypertrophy of FLR and summarized PVE-related complications.

Results: 26 studies including 2335 patients were enrolled in the meta-analysis. All enrolled studies reported data regarding FLR hypertrophy rate, pooled effect size (ES) for FLR hypertrophy rate using a fixed-effect model was 0.105 (95%CI: 0.094-0.117, p=0.000), indicating PVE is favored in inducing FLR hypertrophy. Metatrim method indicated no obvious evidence of publication bias in the present meta-analysis. 247 (10.6%) patients exhibited PVE-related complications, receiving expectant treatment without affecting planned liver resection. Total 1782 patients (76%) underwent a subsequent liver resection after PVE, which is an encouraging result comparing with traditional resection rate in liver tumor patients.

Conclusions: PVE is a safe and effective procedure with a low occurrence of related complications for inducing sufficient hypertrophy of FLR in liver tumor patients, which could elevate the resection rate of liver tumor patients. Careful patient cohort selection is crucial to avoid overuse of PVE in technically resectable patients. Further multiple central clinical trials are conducive to select optimal patient cohorts and provide a guideline for surgeons.

Portal and hepatic vein embolization prior to major hepatectomy

PURPOSE

 To analyze safety and effectiveness of simultaneous portal and hepatic vein embolization (PHVE) or sequential hepatic vein embolization (HVE) compared to portal vein embolization (PVE) for future remnant liver (FRL) hypertrophy prior to major hepatic surgery.

METHODS

 Patients undergoing PVE, PHVE or HVE at our tertiary care center between 2018 and 2020 were retrospectively included. FRLV, standardized FRLV (sFRLV) and sFRLV growth rate per day were assessed via volumetry, as well as laboratory parameters.

RESULTS

 36 patients (f = 15, m = 21; median 64.5 y) were included, 16 patients received PHVE and 20 patients PVE, of which 4 received sequential HVE. Significant increase of FRLV was achieved with both PVE and PHVE compared to baseline (p < 0.0001). sFRLV growth rate did not significantly differ following PHVE (2.2 ± 1.2 %/d) or PVE (2.2 ± 1.7 %/d, p = 0.94). Left portal vein thrombosis (LPVT) was observed after PHVE in 6 patients and in 1 patient after PVE. Sequential HVE showed a considerably high growth rate of 1.42 ± 0.45 %/d after PVE.

CONCLUSION

 PHVE effectively induces FRL hypertrophy but yields comparable sFRLV to PVE. Sequential HVE further induces hypertrophy after insufficient growth due to PVE. Considering a potentially higher rate of LPVT after PHVE, PVE might be preferred in patients with moderate baseline sFRLV, with optional sequential HVE in non-sufficient responders.

A novel model for predicting posthepatectomy liver failure based on liver function and degree of liver resection in patients with hepatocellular carcinoma

BACKGROUND

The permissible liver resection rate for preventing posthepatectomy liver failure (PHLF) remains unclear. We aimed to develop a novel PHLF-predicting model and to strategize hepatectomy for hepatocellular carcinoma (HCC).

METHODS

This retrospective study included 335 HCC patients who underwent anatomical hepatectomy at eight institutions between 2013 and 2017. Risk factors, including volume-associated liver-estimating parameters, for PHLF grade B-C were analyzed in a training set (n = 122) via multivariate analysis, and a PHLF prediction model was developed. The utility of the model was evaluated in a validation set (n = 213).

RESULTS

Our model was based on the three independent risk factors for PHLF identified in the training set: volume-associated indocyanine green retention rate at 15 min, platelet count, and prothrombin time index (the VIPP score). The areas under the receiver operating characteristic curve of the VIPP scores for severe PHLF in the training and validation sets were 0.864 and 0.794, respectively. In both sets, the VIPP score stratified patients at risk for severe PHLF, with a score of 3 (specificity, 0.92) indicating higher risk.

CONCLUSION

Our model facilitates the selection of the appropriate hepatectomy procedure by providing permissible liver resection rates based on VIPP scores.

Influence of surgical approach and quality of resection on the probability of cure for early-stage HCC occurring in cirrhosis

BACKGROUND & AIMS

The quality of surgical care of patients with HCC is associated with improved long-term prognosis and may also be influenced by the type of surgical approach. The present study aimed at evaluating the role of the laparoscopic approach on quality of surgical care and long-term prognosis in optimal HCC surgical candidates.

METHODS

All consecutive patients undergoing open (OLR) or laparoscopic liver resection (LLR) for early-stage HCC in cirrhosis (METAVIR F4) at 5 French expert hepato-pancreatico-biliary centres between 2010 and 2018 were enrolled. Quality of surgical care was defined by textbook outcome (TO), a combination of 6 criteria representing ideal hospitalisation. Factors associated with TO were determined on multivariate analysis. Comparison between LLR and OLR was performed after propensity score matching (PSM). The primary endpoint was disease-free survival (DFS). Statistical cure was modelled using a non-mixture model.

RESULTS

Overall, 425 patients were included. Median follow-up was 42.0 months. LLR was performed in 267 (62.8%) patients. TO was achieved in 140 (32.9%) patients. LLR was independently associated with TO (odds ratio [OR] 2.81; 95% CI 1.29-6.12; p = 0.009). After PSM, LLR patients cumulated higher number of TO criteria than OLR patients (5 vs. 4; p = 0.012). The 1-, 3-, and 5-year DFS of LLR patients with and without TO were 82.3%, 64.4%, and 62.5%, and 76.9%, 51.4%, and 30.2%, respectively (p = 0.003). On multivariable Cox regression, TO was independently associated with improved DFS (hazard ratio 0.34; p = 0.001). The cure fraction of the whole population was 24.4%. Patients achieving TO had increased cure fraction than patients not achieving TO (32.6% vs. 18.1%).

CONCLUSIONS

Quality of surgical care improves the prognosis of patients with early-stage HCC and is promoted by the laparoscopic approach.

LAY SUMMARY

The overall quality of surgical care, as measured by TO, plays a pivotal role in the prognosis and, in particular, on the probability of statistical cure of patients with resectable early-stage HCC occurring in cirrhosis. By influencing TO, laparoscopy has an indirect impact on the probability of cure and long-term management of these patients. This study strongly supports the promising curative role of mini-invasive treatments for early-stage HCC, such as low-difficulty LLR.

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.

The value of a dedicated multidisciplinary expert panel to assess treatment strategy in patients suffering from colorectal cancer liver metastases

BACKGROUND

For patients with colorectal cancer liver metastases (CRLM), local treatment is the only treatment with curative intent. The majority of patients with CRLM are however evaluated in multidisciplinary teams of colorectal cancer specialists often lacking expertise in local treatment of liver tumors. The aim of this study was therefore to assess the value of a dedicated multidisciplinary panel consisting of hepatobiliary surgeons and interventional radiologists for patients suffering from liver-only CRLM.

METHODS

Patients diagnosed with liver-only CRLM in 2016 were identified in a tertiary referral hospital, and two of the referring hospitals in the Netherlands. Diagnostic imaging was independently reviewed by a panel of four hepatobiliary surgeons and two interventional radiologists to re-evaluate treatment strategy retrospectively. If two or more panelists assessed all lesions eligible for resection and/or ablation, patients were deemed eligible for local treatment with curative intent. Interrater reliability between hepatobiliary surgeons was assessed through intraclass correlation coefficient (ICC) and weighted Cohen's kappa.

RESULTS

Diagnostic imaging of 61 patients with liver-only metastases were reviewed. Local treatment strategies appeared feasible in 40/61 (65.6%) patients. Five out of 25 patients (20.0%) initially assigned to systemic therapy were deemed eligible for upfront local treatment with curative intent (p = 0.015). In this subgroup, interrater reliability between hepatobiliary surgeons was substantial (ICC: 0.704, 95% CI: 0.536-0.838, n = 25).

CONCLUSION

Assessment of treatment strategy by a dedicated multidisciplinary panel including liver experts may result in an increased number of patients eligible for potentially curative treatment and reduce undertreatment of patients suffering from liver-only CRLM.

Optimization of transmural care by implementation of an online expert panel to assess treatment strategy in patients suffering from colorectal cancer liver metastases: A prospective analysis

INTRODUCTION

Centralization of oncological care results in a growing demand for specialized consultations and referrals. Improved telemedicine solutions are needed to facilitate access to specialist care and select patients eligible for referral. The purpose of this quality improvement initiative was to optimize transmural care for patients suffering from colorectal cancer liver metastases through implementation of an online expert panel.

METHODS

A digital communication platform was developed to share medical data, including high-quality diagnostic imaging of patients suffering from colorectal cancer liver metastases. Feasibility of local treatment strategies was assessed by a panel of liver specialists to select patients for referral. After implementation, an observational cohort study was conducted to evaluate quality improvement in transmural care using revised Standards for Quality Improvement Reporting Excellence guidelines.

RESULTS

From September 2016-September 2018, eight hospitals were connected to the platform, covering a population of 3 m. In total, 123 cases were assessed, of which 54 (43.9%) were prevented from needless physical referral. Assessment of treatment strategy by an online expert panel significantly reduced the average lead time during multidisciplinary team meetings from 3.73 min to 2.12 min per patient (p < 0.01).

CONCLUSIONS

Implementation of an online expert panel is an innovative, accessible and user-friendly way to provide cancer-specific expertise to regional hospitals. E-consultation of such panels may result in more efficient multidisciplinary team meetings and prevent fragile patients from needless referral. Sustainability of these panels however is subject to structural financial compensation, so a cost-effectiveness analysis is warranted.

Impact of ablation algorithm versus tumor-dependent parameters on local control after microwave ablation of malignant liver tumors

BACKGROUND

The aim of this study is to assess the effect of tumor versus ablation-algorithm dependent parameters on local recurrence (LR) after microwave ablation (MWA) of liver malignancies.

METHODS

This was an institutional review board-approved study of patients who underwent laparoscopic or open MWA of malignant liver tumors. The impact of ablation algorithm (stepwise or direct heating, single or overlapping ablations, and ablation margin) and tumor-dependent (type, size, location, and blood vessel proximity) parameters on LR was analyzed using Kaplan-Meier and Cox proportional hazards.

RESULTS

A total of 179 patients with 602 liver tumors underwent 200 MWA procedures. Colorectal liver metastasis (CLM) was the most frequent tumor type followed by neuroendocrine liver metastasis (NELM), other metastatic tumors, and hepatocellular cancer (HCC). For patients followed at least a year with imaging, LR rate was 8.8% per lesion and 13.1%,1.3%, 11.7%, and 12.6%, for CLM, NELM, HCC, and other tumor types, respectively. On multivariate analysis, independent predictors of LR included tumor type, tumor size, and ablation margin.

CONCLUSION

LR after MWA for malignant liver tumors is predicted by both tumor and surgeon-dependent factors. Variations in the ablation algorithm did not affect LR, leaving the ablation margin as the only parameter that could be modified to optimize local tumor control.

Evaluation of electrical properties of ex vivo human hepatic tissue with metastatic colorectal cancer

OBJECTIVE

To probe the distribution of electrical properties in tumor-bearing human hepatic tissues with metastatic colorectal cancer.

APPROACH

Electrochemical impedance spectroscopy (EIS) and a non-contact electromagnetic probe were used for distinguishing spatial heterogeneities in fresh, unfixed human hepatic tissues ex vivo from patients with metastatic colorectal cancer (CRC).

MAIN RESULTS

Point-wise EIS measurements reported over a frequency range of 100 Hz-1 MHz showed that the interface tissue between visible tumor and normal tissue exhibits an electrically different domain (p < 0.05) from both normal tissue (over 100 Hz-100 kHz) and tumor tissue (over 100 Hz-1 MHz). Observations of the microstructure on tumor-bearing hepatic tissue from hematoxylin and eosin stained images and the equivalent circuit modelling were used to validate the impedance measurements and characterize previously unidentified interfacial domain between normal and tumor tissue. Lastly, in a proof of concept study, a new in-house designed non-contact electromagnetic probe, as opposed to the invasive EIS measurements, was demonstrated for distinguishing tumor tissue from the normal tissue in a hepatic tissue specimen from a patient with metastatic CRC.

SIGNIFICANCE

EIS measurements, correlated with histological observations, show potential for mapping electrical properties in tumor-bearing human hepatic tissue.

Hemostasis and Liver Regeneration

The liver is unique in its remarkable regenerative capacity, which enables the use of liver resection as a treatment for specific liver diseases, including removal of neoplastic liver disease. After resection, the remaining liver tissue (i.e, liver remnant) regenerates to maintain normal hepatic function. In experimental settings as well as patients, removal of up to two-thirds of the liver mass stimulates a rapid and highly coordinated process resulting in the regeneration of the remaining liver. Mechanisms controlling the initiation and termination of regeneration continue to be discovered, and many of the fundamental signaling pathways controlling the proliferation of liver parenchymal cells (i.e., hepatocytes) have been uncovered. Interestingly, while hemostatic complications (i.e., bleeding and thrombosis) are primarily thought of as a complication of surgery itself, strong evidence suggests that components of the hemostatic system are, in fact, powerful drivers of liver regeneration. This review focuses on the clinical and translational evidence supporting a link between the hemostatic system and liver regeneration, and the mechanisms whereby the hemostatic system directs liver regeneration discovered using experimental settings.

Nuclear imaging methods for the prediction of postoperative morbidity and mortality in patients undergoing localized, liver-directed treatments: a systematic review

Background

Several nuclear imaging methods may predict postoperative liver function and outcome, but none has achieved recommendations in clinical guidelines. The purpose of this systematic review was to summarize the existing knowledge on this topic.

Methods

MEDLINE and Web of Science were searched for studies investigating nuclear medicine imaging methods for the prediction of postoperative liver function in patients undergoing localized, liver-directed treatments. The postoperative endpoints were clinical outcome (morbidity and mortality) as well as measures of postoperative liver function, e.g., liver function assessed by biochemical tests or nuclear imaging.

Results

A total of 1352 references were identified, of which 82 fulfilled the eligibility criteria and were included in the review. Most studies (n = 63) were retrospective studies. The vast majority of studies assessed [^99mTc]Tc-galactosyl serum albumin (GSA) (n = 57) and [^99mTc]Tc-mebrofenin (n = 19). Liver resection was entirely or partly major (involved at least three segments) in 78 reports. There were notable variations in the research methodology, e.g., image acquisition, imaging variables, and endpoints. Thirty-seven studies reported on postoperative mortality, of which most reported descriptive data at the patient level. Of the four reports that performed multivariate analyses, two showed significant predictive results of isotope-based preoperative tests. Fifty-two papers presented data on postoperative liver failure. Multivariate predictive analyses were performed in eighteen trials, of which fifteen showed the significant value of nuclear medicine tests.

Conclusion

There is sparse evidence supporting the significant value of nuclear medicine imaging methods in predicting postoperative mortality. In contrast, a notable number of trials showed a significant prediction of liver failure in multivariate analyses. The research methodology was heterogeneous and exploratory in most trials. Documentation of nuclear medicine tests in this setting awaits the results of properly designed, prospective trials with the standardization of both the nuclear medicine test and endpoints.

Taiwan Society of Colon and Rectal Surgeons (TSCRS) Consensus for Cytoreduction Selection in Metastatic Colorectal Cancer

BACKGROUND

Taiwan has witnessed a surge in the incidence of colorectal cancer (CRC), of which 40-60% metastasize. Continuous updating of cytoreductive strategies in metastatic CRC (mCRC) has contributed to median overall survival reaching 40 months. In this changing scenario, to standardize the approaches across Taiwan, a group of experts from the Taiwan Society of Colon and Rectal Surgeons (TSCRS) convened to establish evidence- and opinion-based recommendations for defining the criteria of "resectability" in mCRC.

METHODS

Over the course of one-on-one consultations, lasting 30-40 min each, with 30 medical specialists (19 colorectal surgeons, 4 general surgeons, and 7 medical oncologists) from 16 hospitals in Taiwan followed by a 2-h meeting with 8 physician experts (3 general surgeons, 4 colorectal surgeons, and 1 thoracic surgeon), 12 key questions on cytoreduction were addressed. This was further contextualized based on published literature.

RESULTS

The final consensus includes eight recommendations regarding the criteria for metastasis resection, role of local control treatment in liver potentially resectable patients, management of synchronous liver metastases, approach for peritoneal metastasis, place for resection in multiple-organ metastasis, and general criteria for resectability.

CONCLUSIONS

mCRC patients undergoing R0 resection have the greatest survival advantage following surgery. Our role as a multidisciplinary team (MDT) should be to treat potentially resectable mCRC patients as rapidly and safely as possible, and achieve R0 resection as far as possible and for as long as possible (continuum of care). This TSCRS consensus statement aims to help build clinical capacity within the MDTs, while making better use of existing healthcare resources.

Simultaneous versus staged colorectal and hepatic resections for colorectal cancer with synchronous hepatic metastases: a meta-analysis of outcomes and clinical characteristics

OBJECTIVES

To evaluate the comparative outcomes and clinical characteristics of simultaneous and staged colorectal and hepatic resections for colorectal cancer with synchronous hepatic metastases.

METHODS

We conducted a systematic search of electronic information sources, and bibliographic reference lists. Perioperative morbidity and mortality, anastomotic leak, wound infection, bile leak, bleeding, intra-abdominal abscess, sub-phrenic abscess, reoperation, recurrence, 5-year overall survival, procedure time, and length of hospital stay were the evaluated outcome parameters. Combined overall effect sizes were calculated using random-effects model.

RESULTS

We identified 41 comparative studies reporting a total of 12,081 patients who underwent simultaneous (n = 5013) or staged (n = 7068) resections for colorectal cancer with synchronous hepatic metastases. There were significantly lower use of neoadjuvant chemotherapy (p = 0.003), higher right-sided colonic resections (p < 0.00001), and minor hepatic resections (p < 0.00001) in the simultaneous group. The simultaneous resection was associated with significantly lower rate of bleeding (OR 0.60, p = 0.03) and shorter length of hospital stay (MD - 5.40, p < 0.00001) compared to the staged resection. However, no significant difference was found in perioperative morbidity (OR1.04, p = 0.63), mortality (RD 0.00, p = 0.19), anastomotic leak (RD 0.01, p = 0.33), bile leak (OR 0.83, p = 0.50), wound infection (OR 1.17, p = 0.19), intra-abdominal abscess (RD 0.01, p = 0.26), sub-phrenic abscess (OR 1.26, p = 0.48), reoperation (OR 1.32, p = 0.18), recurrence (OR 1.33, p = 0.10), 5-year overall survival (OR 0.88, p = 0.19), or procedure time (MD - 23.64, p = 041) between two groups.

CONCLUSIONS

Despite demonstrating nearly comparable outcomes, the best available evidence (level 2) regarding simultaneous and staged colorectal and hepatic resections for colorectal cancer with synchronous hepatic metastases is associated with major selection bias. It is time to conduct high-quality randomised studies with respect to burden and laterality of disease. We recommend the staged approach for complex cases.

Postoperative liver regeneration does not elicit recurrence of colorectal cancer liver metastases after major hepatectomy

BACKGROUND AND OBJECTIVES

Recurrence is a frequent concern in curatively resected CRC liver metastases. Translational research suggests that regeneration upon hepatectomy may also alleviate metastatic recurrence; however, the significance in patients is unclear. We therefore sought to study the effect of liver regeneration on tumor recurrence in patients.

METHODS

In this retrospective cohort study, we included 58 out of 186 potentially eligible patients from our prospectively maintained database of CRC liver metastasis patients between 2001 and 2012 with a median follow-up of 42 months who underwent a formal right or left hemihepatectomy. Liver regeneration in CT volumetry was correlated with recurrence of CRC liver metastases and overall survival.

RESULTS

Liver regeneration increased up to 14 months to 21.0% for left and 122.6% for right hemihepatectomy, respectively, with comparable final volumes. Regeneration was independent of initial tumor stage, number of metastases, and preoperative chemotherapy. Patients with lower liver regeneration showed earlier recurrence of CRC liver metastases (p = 0.006). Overall survival did not differ in patients with weak versus strong liver regeneration.

CONCLUSIONS

The extent of liver regeneration after major hepatectomy does not impede overall survival. Therefore, our data encourage aggressive therapeutical regimes for CRC liver metastases involving major hepatectomies as part of a curative approach.

Small-for-size syndrome in liver transplantation: Definition, pathophysiology and management

BACKGROUND

Since the first success in an adult patient, living donor liver transplantation (LDLT) has become an universally used procedure. Small-for-size syndrome (SFSS) is a well-known complication after partial LT, especially in cases of adult-to-adult LDLT. The definition of SFSS slightly varies among transplant physicians. The use of a partial liver graft has risks of SFSS development. Persistent portal vein (PV) hypertension and PV hyper-perfusion after LT were identified as the main factors. Hence, various approaches were explored to modulate PV flow and decrease PV pressure in order to alleviate this syndrome. Herein, the definition, clinical symptoms, pathophysiology, basic research, as well as preventive and treatment strategies for SFSS are reviewed based on an extensive review of the literature and on our own experiences.

DATA SOURCES

The articles were collected through PubMed using search terms "liver transplantation", "living donor liver transplantation", "living liver donation", "partial graft", "small-for-size graft", "small-for-size syndrome", "graft volume", "remnant liver", "standard liver volume", "graft to recipient body weight ratio", "sarcopenia", "porcine", "swine", and "rat". English publications published before March 31, 2020 were included in this review.

RESULTS

Many transplant surgeons performed PV flow modulation, including portocaval shunt, splenic artery ligation and splenectomy. With these techniques, patient outcome has been improved even when using a "small" graft. Other factors, such as preoperative recipients' nutritional and skeletal muscle status, graft congestion, and donor factors, were also identified as risk factors which all have been addressed using various strategies.

CONCLUSIONS

The surgical approach controlling PV flow and pressure could help to prevent SFSS especially in severely ill recipients. In the absence of efficacious medications to resolve SFSS, conservative treatments, including aggressive fluid balance correction for massive ascites, anti-microbiological therapy to prevent or control sepsis and intensive nutritional therapy, are all required if SFSS could not be prevented.

Optimal Timing of Systemic Therapy in Resectable Colorectal Liver Metastases

Perioperative chemotherapy has been shown to improve disease-free survival compared with surgery alone for resectable colorectal liver metastases (CLM). We examined our experience with systemic chemotherapy in this clinical setting. A prospectively collected liver surgery database identified 210 patients treated for resectable CLM from 1996 to 2010. Results were correlated to four treatment groups: posthepatectomy adjuvant only, prehepatectomy preoperative only, peri-operative (preoperative and adjuvant), and surgery only. Seventy-nine (37.6%) patients received posthepatectomy adjuvant only treatment, 33 (15.7%) received prehepatectomy preoperative only treatment, 46 (21.9%) received perioperative (preoperative and adjuvant) treatment, whereas 52 (24.8%) received surgery alone. Preoperative and adjuvant systemic chemotherapy regimens were as follows: 23 (29.1%) and 18 (14.4%) received a 5-fluorouracil monotherapy regimen, 19 (24.1%) and 31 (24.8%) received an irinotecan-based regimen, and 28 (35.4%) and 37 (29.6%) received an oxaliplatin-based regimen. Nine (11.4%) and 12 (9.6%) received some other unknown combination. Treatment groups showed no difference in gender, mean tumor size, number of tumors, margin status, or postoperative complications with the only difference being a higher incidence of metachronous tumors in the preoperative only and perioperative groups (P = 0.01). Median follow-up and overall survival were 25 and 41 months, respectively. The adjuvant, preoperative, perioperative, and surgery only groups had a median survival time of 48, 35, 39, and 29 months, respectively (log-rank P = 0.04). Independent predictors of overall survival on multivariate analysis included treatment algorithm used and postoperative complication status. Adjuvant only systemic therapy was associated with an improved survival in resectable CLM. Prospective randomized trials are needed to confirm these findings.

Case series of extended liver resection associated with inferior vena cava reconstruction using peritoneal patch

INTRODUCTION

Among various reported techniques for inferior vena cava (IVC) reconstruction, the superiority of one technique over another has not been clearly established. This study aimed at reporting the technical aspects of caval reconstruction using peritoneal patch during extended liver resections.

METHODS

All consecutive patients who underwent extended liver resection associated with anterolateral caval reconstruction using a peritoneal patch from 2016 to 2019 were included in this study. Technical insights, intra-operative details, short and long-term results were reported.

RESULTS

Overall six patients underwent caval reconstruction using peritoneal patch under total vascular exclusion. Half of them required veno-venous bypass. Caval involvement ranged from 30 to 50% of the circumference and from 5 to 7 cm of the length of the IVC. Caval reconstructions was performed using a peritoneal patch harvested from the falciform ligament in four cases and from the right pre-renal peritoneum and right part of the diaphragm in one Case each. Three cases underwent associated reimplantation the remnant hepatic vein. Median intra-operative blood loss and TVE duration were 500 ml and 41 min, respectively. One case experienced a severe complication (liver failure leading to death). R₀ resection was achieved in all patients. All patients had patent IVC and remnant hepatic vein at last follow-up and none was on long-term therapeutic anticoagulation.

CONCLUSION

Caval reconstruction using a peritoneal patch in patients undergoing extended liver resection is feasible and cost-effective and associated with excellent long-term results.

Correlation Between Sarcopenia and Growth Rate of the Future Liver Remnant After Portal Vein Embolization in Patients with Colorectal Liver Metastases

PURPOSE

To investigate whether sarcopenia and myosteatosis correlate with the degree of hypertrophy (DH) and kinetic growth rate (KiGR) of the future liver remnant (FLR) in patients with colorectal liver metastases undergoing portal vein embolization (PVE) in preparation for right hepatectomy.

MATERIALS AND METHODS

Forty-two patients were included. Total liver volume and FLR volume were measured before and 2-4 weeks after PVE. KiGR of the FLR was calculated. Sarcopenia was assessed using the total psoas muscle volume (PMV), the psoas muscle cross-sectional area (PMCS) and the total skeletal muscle index (L3SMI) at the level of 3rd lumbar vertebra. Degree of myosteatosis was assessed by mean muscle attenuation at L3 (L3MA). Correlations between muscle indices and DH and KiGR were assessed using simple linear regression analyses.

RESULTS

Mean DH was 8.9 ± 5.7%, and mean KiGR was 3.6 ± 2.3. Mean PMV was 55.56 ± 14.19 cm3/m3, mean PMCS was 8.76 ± 2.3 cm2/m2, mean L3SMI was 45.6 ± 9.89 cm2/m2, and mean L3MA was 27.9 ± 18.6 HU. There was a strong positive correlation between PMV and DH (R = 0.503, p = 0.001) and PMV and KiGR (R = 0.545, p < 0.001). Furthermore, there was a moderate correlation between PMCS and KiGR (R = 0.389, p = 0.014). L3SMI and L3MA were neither associated with DH (p = 0.390 and p = 0.768, respectively) nor with KiGR (p = 0.188 and p = 0.929, respectively).

CONCLUSION

We identified a positive correlation between PMV and PMCS, as markers for sarcopenia, and the KiGR of the FLR after PVE. PMV and PMCS might therefore aid to identify patients who are poor candidates for FLR augmentation using PVE alone.

Relevance of liver surface nodularity for preoperative risk assessment in patients with resectable hepatocellular carcinoma

BACKGROUND

Quantification of liver surface nodularity (LSN) on routine preoperative CT images allows detection of cirrhosis and clinically significant portal hypertension. This study aimed to assess the relevance of LSN in preoperative assessment of operative risks for patients with resectable hepatocellular carcinoma (HCC).

METHODS

All patients undergoing hepatectomy for HCC between 2012 and 2017 were analysed retrospectively. LSN was assessed at the liver-fat interface on the left liver lobe on preoperative CT images. The feasibility of LSN quantification was assessed. The association between LSN and outcomes (severe complications and posthepatectomy liver failure (PHLF)) was evaluated by multivariable analysis and after propensity score matching.

RESULTS

Among 210 patients, LSN measurement was successful in 187 (89·0 per cent). Among these, the median LSN score was 2·42 (i.q.r. 2·21-2·66) and 52·9 per cent had severe fibrosis, including 33·7 per cent with cirrhosis. LSN score increased with hepatic venous pressure gradient (P = 0·048), severity of steatosis (P = 0·011) and fibrosis grade (P = 0·001). LSN score was independently associated with severe complications (odds ratio (OR) 5·25; P = 0·006) and PHLF (OR 6·78; P = 0·003). After matching with respect to model for end-stage liver disease, aspartate aminotransferase-to-platelet ratio index and fibrosis-4 score, patients with a LSN score of 2·63 or higher retained an increased risk of PHLF (OR 5·81; P = 0·018). In the subgroup of patients without severe fibrosis, LSN was accurate in predicting severe complications (P = 0·005). Patients with (P = 0·039) or without (P = 0·018) severe fibrosis with increased LSN score had a higher comprehensive complication index score. Among patients with cirrhosis who had clinically significant portal hypertension, a LSN value below 2·63 ruled out the risk of PHLF.

CONCLUSION

LSN measurement represents a practical tool that may allow improvement in the preoperative evaluation and management of patients with HCC.

Survival Benefit of and Indications for Adjuvant Chemotherapy for Resected Colorectal Liver Metastases-a Japanese Nationwide Survey

BACKGROUND

The survival benefit of and indications for adjuvant chemotherapy (AC) for colorectal liver metastases (CRLM) remain unclear.

METHODS

Patients who were diagnosed with liver-limited CRLM between 2005 and 2007 and subsequently underwent R0 resection without preoperative chemotherapy were identified in a Japanese nationwide survey. This overall cohort was divided into synchronous and metachronous CRLM cohorts. In each of the three cohorts, the patients that were given AC were matched with those treated with surgery alone via 1:1 propensity score (PS) matching. Recurrence-free survival (RFS) and overall survival (OS) after the initial hepatectomy were compared.

RESULTS

The median follow-up period was 79.4 months and the overall, synchronous, and metachronous cohorts included 1145, 498, and 647 patients, respectively. After the PS matching, the patients' demographics were well balanced. AC was effective in terms of both RFS and OS in the overall cohort (RFS hazard ratio [HR] 0.784, p = 0.045; OS HR 0.716, p = 0.028) and synchronous cohort (RFS HR 0.677, p = 0.027; OS HR 0.642, p = 0.036), whereas AC was not effective in the metachronous cohort (RFS HR 0.875, p = 0.378; OS HR 0.881, p = 0.496). However, in the metachronous cohort, AC was effective in terms of OS in the subgroup that exhibited disease-free intervals of ≤ 1 year after primary tumor resection (RFS HR 0.667, p = 0.068; OS HR 0.572, p = 0.042).

CONCLUSION

Adjuvant chemotherapy has a survival benefit for patients with resected CRLM. Synchronous CRLM is a favorable indication for AC, whereas in metachronous CRLM, the use of AC should be individualized according to each patient's risk factors.

Hepatic volume changes post-selective internal radiation therapy with 90 Y microspheres

INTRODUCTION

To examine the hepatic volume changes post-selective internal radiation therapy with ⁹⁰ Y microspheres. This technique has been demonstrated to be a suitable alternative to portal vein embolisation to induce hypertrophy of the future liver remnant (FLR) in patients with malignant disease of the liver preoperatively. The role of both techniques is to decrease postoperative morbidity and increase the numbers of patients eligible for surgical resection. Unlike portal vein embolisation, radioembolisation has the additional benefit of treating liver malignancy and reducing the risk of tumour progression during the hypertrophy period.

METHODS

A retrospective analysis was conducted of 29 patients from August 2012 to November 2016 that had right liver lobe malignant disease (primary or secondary) and underwent selective internal radiation therapy. Changes in liver volume were measured from CT or MRI before treatment and at 3, 6 and 12 months post-SIRT.

RESULTS

Eighteen patients (62%) had primary liver malignancies (HCC n = 15, cholangiocarcinoma n = 3), and 11 patients (38%) had metastases (colorectal carcinoma n = 10, ampullary carcinoma n = 1). There was a mean increase in the FLR volume relative to baseline of 37.2% at 3 months (n = 25), 42.6% at 6 months (n = 19) and 63.5% at 12 months (n = 12). There was a mean decrease in whole liver volume at 12 months by -13.3%.

CONCLUSION

Right liver lobe SIRT induces left liver lobe (FLR) compensatory hypertrophy. This study's data support the use of SIRT in selected patients with right liver lobe malignancy to undergo SIRT to facilitate liver resection.

Predicting Overall Survival in Patients with Metastatic Rectal Cancer: a Machine Learning Approach

BACKGROUND

A significant proportion of patients with rectal cancer will present with synchronous metastasis at the time of diagnosis. Overall survival (OS) for these patients are highly variable and previous attempts to build predictive models often have low predictive power, with concordance indexes (c-index) less than 0.70.

METHODS

Using the National Cancer Database (2010-2014), we identified patients with synchronous metastatic rectal cancer. The data was split into a training dataset (diagnosis years 2010-2012), which was used to build the machine learning model, and a testing dataset (diagnosis years 2013-2014), which was used to externally validate the model. A nomogram predicting 3-year OS was created using Cox proportional hazard regression with lasso penalization. Predictors were selected based on clinical significance and availability in NCDB. Performance of the machine learning model was assessed by c-index.

RESULTS

A total of 4098 and 3107 patients were used to construct and validate the nomogram, respectively. Internally validated c-indexes at 1, 2, and 3 years were 0.816 (95% CI 0.813-0.818), 0.789 (95% CI 0.786-0.790), and 0.778 (95% CI 0.775-0.780), respectively. External validated c-indexes at 1, 2, and 3 years were 0.811, 0.779, and 0.778, respectively.

CONCLUSIONS

There is wide variability in the OS for patients with metastatic rectal cancer, making accurate predictions difficult. However, using machine learning techniques, more accurate models can be built. This will aid patients and clinicians in setting expectations and making clinical decisions in this group of challenging patients.

Preoperative three-dimensional versus two-dimensional evaluation in assessment of patients undergoing major liver resection for hepatocellular carcinoma: a propensity score matching study

Background

Compared with 2D evaluation, 3D evaluation possesses the virtues of displaying spatial anatomy of intrahepatic blood vessels and its relations to tumors, and enabling calculation of liver volumes, thus facilitating preoperative surgery planning.

Methods

The objective of this study is to study whether preoperative 3D (three-dimensional) evaluation produced better long-term overall survival (OS) outcomes compared to the traditional 2D (two-dimensional) evaluation in patients who underwent major hepatectomy for hepatocellular carcinoma (HCC). This retrospective study matched patients who underwent preoperative 2D evaluation with those who underwent preoperative 3D evaluation in a 1:1 ratio using propensity score matching. The primary endpoints were long-term survival outcomes in the two groups after major hepatectomy for HCC.

Results

Of the 248 patients in each of the 2 matched groups, the baseline characteristics were comparable. The median follow-up for all patients was 36 months (range, 0-40 months). The 3-year OS of patients in the PSM cohort was 38.5%. Compared with the 2D Group, patients in the 3D Group had a better OS rate (HR 0.722, 95% CI: 0.556-0.938, P=0.015) and disease-free survival (DFS) rate (HR 0.741, 95% CI: 0.590-0.929, P=0.009). The 3-year OS and DFS rate for the 3D Group versus the 2D group were 58.9% and 44.0% versus 47.4% and 33.1%, respectively.

Conclusions

3D preoperative evaluation resulted in significantly better intermediate-term (3-year) overall survival rate than the traditional 2D evaluation.

The added value of dual-time-point 18F-FDG PET/CT imaging in the diagnosis of colorectal cancer liver metastases

PURPOSE

To investigate the added value of dual-time-point ¹⁸F-FDG PET/CT imaging in the diagnosis of colorectal cancer liver metastases (CRLM).

METHODS

One hundred and eight patients with CRLM preoperatively underwent a dual-time-point ¹⁸F-FDG PET/CT scan. All hepatic lesions were diagnosed by histopathology. The diagnostic sensitivity of ¹⁸F-FDG PET/CT for CRLM was calculated on early scan and delayed scan, respectively. The McNemar test was used to test the differences of the sensitivity and the specificity between early scan and delayed scan.

RESULTS

On a per-patient basis, no significant difference in sensitivity was found between early scan and delayed scan (92.93% vs. 96.97%, P = 0.125). The per-patient specificity of early and delayed scans was 77.78%. On a per-lesion basis, overall sensitivity of delayed scan was significantly higher than that of early scan (83.49% vs. 76.61%, P < 0.001). The per-lesion specificity of early and delayed scans was 69.23%. For the lesion size of CRLM ≤ 10 mm, delayed imaging had significantly higher sensitivity than early imaging (47.17% vs. 26.42%, P < 0.001). However, for CRLM > 10 mm, there was no significant difference in sensitivity between early and delayed scans (92.73% vs. 95.15%, P = 0.125). Of the detected 182 liver metastatic lesions on delayed scan, the SUV_max on delayed scan was significantly higher than that on early scan (12.13 ± 7.13 vs. 9.16 ± 4.74, P < 0.001). The SUVmean of the normal liver on delayed scan was significantly lower than that on early scan (1.91 ± 0.29 vs. 2.33 ± 0.31, P < 0.001). The tumor to normal background ratio on delayed scan was significantly higher than that on early scan (6.59 ± 4.43 vs. 4.02 ± 2.23, P < 0.001).

CONCLUSION

The dual-time-point ¹⁸F-FDG PET/CT imaging might detect more CRLM lesions compared with single-time-point imaging, especially for small (< 10 mm) lesions.

Is laparoscopic liver resection suitable for selected patients with BCLC stage B HCC? A propensity score-matched analysis

BACKGROUND

The optimal treatment for patients with Barcelona Clinic Liver Cancer (BCLC) stage B hepatocellular carcinoma (HCC) is controversial given the variability of tumour status within this group of patients. This aim of this study was to compare the outcomes of laparoscopic liver resection (LLR) to transarterial chemoembolization (TACE) in a subset of selected patients with BCLC stage B HCC.

METHODS

Patients with resectable BCLC stage B HCC who underwent treatment between April 2015 and October 2018 were identified for further analysis. Propensity score matching (PSM) was conducted to minimize effect of confounding factors. Perioperative and long-term outcomes were compared between the two groups and multivariate analysis was performed to identify risk factors related to the overall survival (OS).

RESULTS

From a total of 224 patients 70 were included into each group after PSM. The overall and major morbidity were comparable between the LLR and TACE groups (P = 0.700 and P = 0.500 after PSM, respectively). The OS in LLR group was significantly better than that in the TACE group (P < 0.001). Tumor number ≥4, the diameter of the biggest tumor >5 cm, and patients who underwent TACE were independent predictors of poorer OS.

CONCLUSIONS

LLR for selected patients with BCLC stage B HCC is safe and feasible and has improved survival as compared to TACE.

Clinical impact of radiofrequency ablation and stereotactic body radiation therapy for colorectal liver metastasis as local therapies for elderly, vulnerable patients

Background and Aim

Surgical resection is the standard local therapy for patients with colorectal liver metastases (CRLM). However, elderly and vulnerable patients sometimes have various organ dysfunctions. We have to conduct nonsurgical local therapies for those patients who might not tolerate surgery or systemic chemotherapy.

Methods

We retrospectively reviewed medical records of 254 patients who underwent local therapies, including surgery, radiofrequency ablation (RFA), and stereotactic body radiation therapy (SBRT), for CRLM from January 2010 to December 2016, at seven tertiary‐care institutions in Japan. This study was designed to include elderly, vulnerable patients who received local therapy for CRLM. For those undergoing liver resection, only those having one or more points of the Charlson comorbidity index (CCI) were enrolled.

Results

Of the total 169 enrolled patients, 122 patients underwent surgery, 42 RFA, and 5 SBRT as the first local therapy for CRLM. Median overall survival from the first local therapy was 5.9 years for the surgery group, 2.7 years for the RFA group, and 3.8 years for the SBRT group. The proportion of the patients with CCI ≧3 was significantly higher in the group of RFA/SBRT than surgery (P < 0.0001). In selected patients with CCI ≧3, there was no difference of the median survival time between the surgery group and the RFA group.

Conclusions

We could have other treatment options to provide nonsurgical local therapies (RFA/SBRT) for elderly, vulnerable CRLM patients who have risks for surgery.

Nomogram for predicting overall survival in stage II-III colorectal cancer

PURPOSE

The overall survival (OS) of patients diagnosed with stage II-III colorectal cancer (CRC) can vary greatly, even between patients with the same tumor stage. We aimed to design a nomogram to predict OS in resected, stage II-III CRC and stratify patients with CRC into different risk groups.

PATIENTS AND METHODS

Based on data from 873 patients with CRC, we used univariate Cox regression analysis to select the significant prognostic features, which were subjected to the least absolute shrinkage and selection operator (LASSO) regression algorithm for feature selection. Cross-validation was used to confirm suitable tuning parameters (λ) for LASSO logistic regression. Then, the nomogram was used to estimate 3- and 5-year OS based on the multivariable Cox regression model. The survival curves of the two groups were produced using the Kaplan-Meier method. Risk group stratification was performed to assess the predictive capacity of the nomogram.

RESULTS

Preoperative mean platelet volume, preoperative platelet distribution width, monocytes, and postoperative adjuvant chemotherapy were identified as independent prognostic factors by LASSO regression and integrated for the construction of the nomogram. The nomogram provided good discrimination, with C-indices of 0.67 and 0.69 for the training and validation sets, respectively. Calibration plots illustrated excellent agreement between the nomogram predictions and actual observations for 3- and 5-year OS. Moreover, a significant difference in OS was shown between patients stratified into different risk groups (P < .001).

CONCLUSION

We constructed and validated an original predictive nomogram for OS in patients with CRC after surgery, facilitating physicians to appraise the individual survival of postoperative patients accurately and identify high-risk patients who need more aggressive treatment and follow-up strategies.

Liver resection is beneficial for patients with colorectal liver metastases and extrahepatic disease

Background

Liver metastases are the most common cause of death for patients with colorectal cancer and affect up to half of the patients. Liver resection is an established method that can potentially be curative. For patients with extrahepatic disease (EHD), the role of liver surgery is less established.

Methods

This is a retrospective study based on data from the national quality registry SweLiv. Data were obtained between 2009 and 2015. SweLiv is a validated registry and has been in use since 2009, with coverage above 95%. Patients with liver metastases and EHD were analyzed and cross-checked against the national death cause registry for survival analysis.

Results

During the study period, 2,174 patients underwent surgery for colorectal liver metastases (CRLM), and 277 patients with EHD were treated with resection or ablation. The estimated median survival time for the entire cohort from liver resection/ablation was 40 months (95% CI, 32-47). The survival time for patients treated with liver resection was 45 months compared to 26 months for patients treated with ablation (95% CI 38-53, 18-33, P=0.001). A subgroup analysis of resected patients revealed that the group with pulmonary metastases had a significantly longer estimated median survival (50 months; 95% CI, 39-60) than the group with lymph node metastases (32 months; 95% CI, 7-58) or peritoneal carcinomatosis (28 months; 95% CI, 14-41) (P=0.022 and 0.012, respectively). Other negative prognostic factors were major liver resection and nonradical liver resection.

Conclusions

For patients with liver metastases and limited EHD, liver resection results in prolonged survival compared to what can be expected from chemotherapy alone.

Surgical approach to synchronous colorectal liver metastases: staged, combined, or reverse strategy

An increasing number of patients with colorectal cancer (CRC) are presenting with synchronous disease to the liver. The optimal surgical approach for this complex patient group is controversial, but ultimately depends on individual patient characteristics and institutional practices. Surgical strategies include the traditional staged approach, a combined colorectal and liver resection, or a liver-first reverse approach. In this review, the authors will provide an overview of each strategy, including case examples demonstrating the benefits of the more recently described liver-first approach, while arguing for individualized planning and multidisciplinary discussion for every patient.

Impact of cirrhosis in patients undergoing laparoscopic liver resection in a nationwide multicentre survey

BACKGROUND

The aim was to analyse the impact of cirrhosis on short-term outcomes after laparoscopic liver resection (LLR) in a multicentre national cohort study.

METHODS

This retrospective study included all patients undergoing LLR in 27 centres between 2000 and 2017. Cirrhosis was defined as F4 fibrosis on pathological examination. Short-term outcomes of patients with and without liver cirrhosis were compared after propensity score matching by centre volume, demographic and tumour characteristics, and extent of resection.

RESULTS

Among 3150 patients included, LLR was performed in 774 patients with (24·6 per cent) and 2376 (75·4 per cent) without cirrhosis. Severe complication and mortality rates in patients with cirrhosis were 10·6 and 2·6 per cent respectively. Posthepatectomy liver failure (PHLF) developed in 3·6 per cent of patients with cirrhosis and was the major cause of death (11 of 20 patients). After matching, patients with cirrhosis tended to have higher rates of severe complications (odds ratio (OR) 1·74, 95 per cent c.i. 0·92 to 3·41; P = 0·096) and PHLF (OR 7·13, 0·91 to 323·10; P = 0·068) than those without cirrhosis. They also had a higher risk of death (OR 5·13, 1·08 to 48·61; P = 0·039). Rates of cardiorespiratory complications (P = 0·338), bile leakage (P = 0·286) and reoperation (P = 0·352) were similar in the two groups. Patients with cirrhosis had a longer hospital stay than those without (11 versus 8 days; P = 0·018). Centre expertise was an independent protective factor against PHLF in patients with cirrhosis (OR 0·33, 0·14 to 0·76; P = 0·010).

CONCLUSION

Underlying cirrhosis remains an independent risk factor for impaired outcomes in patients undergoing LLR, even in expert centres.

Liver metastases in gastroenteropancreatic neuroendocrine tumours - treatment methods

Surgical approaches that allow the safe treatment of multiple, bilateral, large tumours, and that combine extirpative, ablative and interventional therapies, have expanded the population of patients with neuroendocrine tumors (NET) liver metastases (LMs) who can benefit from aggressive treatment of their liver disease. Pre-treatment staging often includes the biochemical assessment of serologic markers such as serotonin, insulin, vasoactive intestinal peptide, and chromogranin, even in patients without clinically apparent hormonal excess. Radiofrequency ablation (RFA) is a technique that involves the use of thermal energy to induce coagulation necrosis, thereby destroying tumour cells. Resection plus RFA is increasingly used in patients with bilateral NET LMs. Resection is performed for large or dominant lesions, while ablation is used to treat small lesions. Hepatic arterial embolization, typically termed transarterial embolization, and transarterial chemoembolization have been shown to induce a reduction in tumour size and to ameliorate symptoms of excess hormonal secretion.

Simultaneous versus staged resection for synchronous colorectal liver metastases: A population-based cohort study

BACKGROUND

Synchronous liver metastases from colorectal cancer may be resected simultaneously with the primary or as a second staged operation. We evaluated trends of resection for synchronous colorectal cancer liver metastases and associated patient outcomes.

METHODS

This is a retrospective cohort study that included patients undergoing resection for synchronous colorectal cancer liver metastases from 2006 to 2015 in the province of Ontario, Canada (population 13 million). Simultaneous resections occurred on the same admission, while staged resections occurred less than 6 months apart. Outcomes included postoperative complications, length of hospital stay, and overall survival. Kaplan Meier survival estimates, Cox proportional hazard models and logistic regression were used.

RESULTS

Among 2,738 patients undergoing resection for colorectal cancer liver metastases, 1168 (42%) had synchronous disease. Of these, 442 resections were simultaneous (38%) and 776 were staged (62%). The proportion of synchronous disease among patients undergoing resection increased on average 3% per year (p = 0.02). For simultaneous versus staged resection, respectively, median length of hospital stay was shorter (8 vs. 11 days, p < 0.001); rate of major liver resections was lower (17% vs. 65%, p < 0.001), major postoperative complications were similar (28% vs. 23%, p = 0.067), and 90-day post-operative mortality was higher (6% vs. 1%, p < 0.001). Chemotherapy was administered more commonly among patients undergoing staged resections (91% vs. 76%, p < 0.001). Simultaneous resection was associated with a lower median overall survival (40 months, 95%CI 35-46 vs. 78 months, 95%CI 59-86). Risk factors for lower survival included higher comorbidities, right-sided primary and simultaneous resection.

CONCLUSION

Simultaneous resection was associated with similar postoperative complications, higher postoperative mortality and poorer long-term survival. Prospective randomized trials can inform the role of simultaneous versus staged resection for synchronous colorectal cancer liver metastases.

N6-methyladenosine modification of circNSUN2 facilitates cytoplasmic export and stabilizes HMGA2 to promote colorectal liver metastasis

Circular RNAs (circRNAs) have been implicated in cancer progression through largely unknown mechanisms. Herein, we identify an N⁶-methyladenosine (m⁶A) modified circRNA, circNSUN2, frequently upregulated in tumor tissues and serum samples from colorectal carcinoma (CRC) patients with liver metastasis (LM) and predicts poorer patient survival. The upregulated expression of circNSUN2 promotes LM in PDX metastasis models in vivo and accelerates cancer cells invasion in vitro. Importantly, N⁶-methyladenosine modification of circNSUN2 increases export to the cytoplasm. By forming a circNSUN2/IGF2BP2/HMGA2 RNA-protein ternary complex in the cytoplasm, circNSUN2 enhances the stability of HMGA2 mRNA to promote CRC metastasis progression. Clinically, the upregulated expressions of circNSUN2 and HMGA2 are more prevalent in LM tissues than in primary CRC tissues. These findings elucidate that N⁶-methyladenosine modification of circNSUN2 modulates cytoplasmic export and stabilizes HMGA2 to promote CRC LM, and suggest that circNSUN2 could represent a critical prognostic marker and/or therapeutic target for the disease.