Preoperative liver hypertrophy induced by portal flow occlusion before major hepatic resection for colorectal metastases can be impaired by bevacizumab

Two cases of hepatocellular carcinoma successfully treated by carbon ion radiotherapy after atezolizumab plus bevacizumab treatment

We herein report two cases of huge hepatocellular carcinoma (HCC) that were successfully treated by carbon ion radiotherapy after atezolizumab plus bevacizumab treatment. Case 1, an 84-year-old man, was diagnosed with HCC (maximum diameter: 11 cm) with portal invasion and presented HCC rupture. After obtaining hemostasis with transcatheter embolization, three cycles of atezolizumab-bevacizumab therapy were administered, and marked shrinkage of the HCC was confirmed. However, he developed jaundice, liver damage and cerebral subcortical hemorrhage. Thus, atezolizumab-bevacizumab therapy was discontinued. Total bilirubin, transaminase levels, and physical activity improved well with prednisolone, an antihypertensive agent, and rehabilitation. Thus, treatment with carbon ion radiotherapy (CIRT) was added, and the treatment effect at 4 months after CIRT was judged as a complete response (CR) according to the modified response evaluation criteria in solid tumors (mRECIST). Case 2, a 68-year-old man, was diagnosed with HCC (maximum diameter: 14 cm). Hepatic resection was difficult because the residual liver volume after treatment would be insufficient. Five cycles of atezolizumab-bevacizumab therapy were performed, and marked shrinkage of the HCC to a maximum diameter of 9 cm was confirmed. The treatment was converted to CIRT, and atezolizumab-bevacizumab therapy resumed one month after CIRT. The treatment effect at 3 months after CIRT was judged as CR according to mRECIST. Although conversion therapy after atezolizumab-bevacizumab therapy, including surgery and radiofrequency ablation, have been reported, CIRT may be a promising new tool for conversion therapy for HCC.

A case of conversion hepatectomy for huge hepatocellular carcinoma with adrenal metastasis and vascular invasion after atezolizumab-bevacizumab treatment

We herein report a case of huge hepatocellular carcinoma (HCC) with adrenal metastasis and vascular invasion successfully treated by conversion hepatectomy after atezolizumab-bevacizumab treatment. A 77-year-old male patient with chest pain was admitted. He had a history of HCC treatment; however, the patient stopped receiving follow-up treatment based on his own decision. This time, he visited the emergency department of our hospital for the first time in 5 years. The tumor at the right lobe had grown into a lump with adrenal metastases and was 15 cm in diameter. It had invaded the inferior vena cava. Atezolizumab-bevacizumab treatment was selected for HCC treatment. Before starting treatment, his liver function was preserved (Child-Pugh A5). His alpha fetoprotein (AFP) and des-gamma-carboxyprothrombin (DCP) levels were 759.0 ng/mL and 5,681 mAU/mL, respectively. Atezolizumab-bevacizumab treatment resulted in a marked decrease in tumor marker levels and tumor staining. After nine courses of atezolizumab-bevacizumab treatment, it became difficult to continue the administration of bevacizumab because of proteinuria. Because the tumor had decreased in size and the tumor markers were in the normal range, we decided to perform conversion hepatectomy. The tumor was completely removed by combined resection of the diaphragm, and pathological analyses showed a complete response to atezolizumab-bevacizumab treatment. No viable tumor cells remained on histological analyses. The patient is doing well without any signs of recurrence at 3 months after conversion surgery.

Imaging-guided interventions modulating portal venous flow: evidence and controversies

Portal hypertension is defined by an increase in the portosystemic venous gradient. In most cases, increased resistance to portal blood flow is the initial cause of elevated portal pressure. More than 90% of cases of portal hypertension are estimated to be due to advanced chronic liver disease or cirrhosis. Transjugular intrahepatic portosystemic shunts, a non-pharmacological treatment for portal hypertension, involve the placement of a stent between the portal vein and the hepatic vein or inferior vena cava which helps bypass hepatic resistance. Portal hypertension may also be a result of extrahepatic portal vein thrombosis or compression. In these cases, percutaneous portal vein recanalisation restores portal trunk patency, thus preventing portal hypertension-related complications. Any portal blood flow impairment leads to progressive parenchymal atrophy and triggers hepatic regeneration in preserved areas. This provides the rationale for using portal vein embolisation to modulate hepatic volume in preparation for extended hepatic resection. The aim of this paper is to provide a comprehensive evidence-based review of the rationale for, and outcomes associated with, the main imaging-guided interventions targeting the portal vein, as well as to discuss the main controversies around such approaches.

Increased Hepatic Microvascular Density, Oxygenation, and VEGF in the Hypertrophic Lobe following Portal Vein Embolization in Rabbits

INTRODUCTION

The microvascular events following portal vein embolization (PVE) are poorly understood despite the pivotal role of the microcirculation in liver regeneration and tumor progression. We aimed to assess the changes in hepatic microvascular perfusion and neo-angiogenesis after experimental PVE.

METHODS

PVE of the cranial liver lobes was performed in 12 New Zealand White rabbits divided into 2 groups of permanent (P-PVE) and reversible PVE (R-PVE), respectively. Hepatobiliary scintigraphy and CT were used to evaluate hepatic function and volume. Hepatic microcirculation was assessed using a handheld vital microscope (Cytocam) to measure microvascular density (total vessel density; TVD) before PVE, right after PVE, and 20 min after PVE, as well as at 14 days (D14 post-PVE) and 35 days (D35 post-PVE). Additionally, on D35, microvascular PO2 and liver parenchymal VEGF were assessed.

RESULTS

Eleven rabbits were included after PVE (R-PVE, n = 5; P-PVE, n = 6). TVD in the nonembo-lized (hypertrophic) lobes was higher than in the embolized (atrophic) lobes of the P-PVE group at D35 post-PVE (36.7 ± 7.2 vs. 23.4 ± 4.9 mm/mm2; p < 0.05). In the R-PVE group, TVD in the nonembolized lobes was not increased at D35. Function and volume were increased in the nonembolized lobes of the P-PVE group compared to the embolized lobes, but not in the R-PVE group. Likewise, the mmicrovascular PO2 and VEGF staining rate were higher in the nonembolized lobes of the P-PVE group at D35 post-PVE.

DISCUSSION/CONCLUSION

Successful volumetric and functional hypertrophy of the nonembolized lobe was accompanied by microvascular alterations featuring increased neo-angiogenesis, microvascular density, and microvascular oxygen pressure following P-PVE.

Issues to be considered to address the future liver remnant prior to major hepatectomy

An accurate preoperative evaluation of the hepatic function and application of portal vein embolization in selected patients have helped improve the safety of major hepatectomy. In planning major hepatectomy, however, several issues remain to be addressed. The first is which cut-off values for serum total bilirubin level and prothrombin time should be used to define post-hepatectomy liver failure. Other issues include what minimum future liver remnant (FLR) volume is required; whether the total liver volume measured using computed tomography or the standard liver volume calculated based on the body surface area should be used to assess the adequacy of the FLR volume; whether there is a discrepancy between the FLR volume and function during the recovery period after portal vein embolization or hepatectomy; and how best the function of a specific FLR can be assessed. Various studies concerning these issues have been reported with controversial results. We should also be aware that different strategies and management are required for different types of liver damage, such as cirrhosis in hepatocellular carcinoma, cholangitis in biliary tract cancer, and chemotherapy-induced hepatic injury.

Portal Vein Embolization: Radiological Findings Predicting Future Liver Remnant Hypertrophy

OBJECTIVE. The purpose of this article is to evaluate the radiologic findings predicting the future liver remnant hypertrophy ratio after portal vein embolization of the right branch. MATERIALS AND METHODS. The associations between the radiologic findings and the future liver remnant hypertrophy ratio for 79 patients who underwent portal vein embolization of the right branch between July 2007 and April 2017 were retrospectively analyzed. Multiple linear regression was performed to adjust for potential confounders, and the volume ratio of the right lobe anterior segment, number of proximal small branches from the right anterior and posterior portal veins, transient hepatic parenchymal enhancement, portal vein invasion, and variants of main portal vein anatomy were evaluated. The potential confounders were age, ratio of future liver remnant hypertrophy to total liver volume, indocyanine green clearance rate, maximum serum total bilirubin before portal vein embolization, and history of chemotherapy. RESULTS. Statistically significant associations were found between the future liver remnant hypertrophy ratio and the number of proximal small branches from the right anterior and posterior portal veins (p < 0.001), transient hepatic parenchymal enhancement (p < 0.001), portal vein invasion (p = 0.017), and variants of main portal vein anatomy (p = 0.048). The mean future liver remnant hypertrophy rate was 51.0% (n = 16) in patients without the radiologic findings showing statistically significant differences, and 25.8% (n = 63) in patients with at least one significant finding. CONCLUSION. When added to previously reported factors, the radiologic findings identified can help determine the indications for portal vein embolization and novel strategies for major hepatectomy.

Bevacizumab Allows Preservation of Liver Function and its Regenerative Capacity after Major Hepatectomy

BACKGROUND

Parallel to the safety of liver resections, new chemotherapy drugs have emerged for the control of liver metastases. However, there is unclear evidence about the combination of intensive BVZ-therapy and extended resections. The main aim was to analyse the impact of Bevacizumab (BVZ) in terms of liver safety and tolerability in two experimental models: a basal-toxicity situation and after major hepatectomy.

METHODS

Eighty male-Wistar rats were grouped as toxicity analysis (sham-operated rats-OS-) and regeneration after- surgery analysis (hepatectomy rats-H-). Eight further subgroups were created according to sacrifice (6- hours-6h- or 24-hours-24h-) and dose (μg) of BVZ (none, 100, 200, 400). Several measurements were performed, including biochemical serum samples, histopathological analysis, cytokines (IL-6, TNF-α, TGF-β), oxidative-stress (GSH/GSSG, ATP), lipid-peroxidation (TBARS) and epidermal and vascular endothelium growth-factors (EGF and VEGF).

RESULTS

In the toxicity analysis, safe results with BVZ were observed, with no significant differences among the groups. A trend towards a lower oxidative status was observed in the OS 6 h-100, -200 and -400 versus the OS 6 h-none group. Similar results were observed in the hepatectomy model, with stable oxidative-stress-index and IL-6, TNF- α, and TGF- β levels. Despite higher lipid peroxidation status, overall regeneration was preserved. As expected, VEGF was almost undetectable in BVZ-treated groups after resection, but not in the non-resection group.

CONCLUSION

It was concluded that liver status was not impaired by BVZ even at the high-dose. Similarly, liver regeneration after extended hepatectomy in BVZ-treated animals was well-preserved. Extended liver resections may be encouraged in BVZ-treated patients due to its excellent tolerability and good liver regeneration status.

Future Liver Remnant (FLR) Increase in Patients with Colorectal Liver Metastases Is Highest the First Week After Portal Vein Occlusion : FLR Increase in Patients with CRLM Is Highest the First Week After PVO

BACKGROUND

Portal vein occlusion (PVO) is an established method to increase the volume of the future liver remnant (FLR). The main reasons for not proceeding to radical hepatectomy are lack of volume increase and tumor progression due to a wait-time interval of up to 8 weeks. The hypothesis was that the increase in FLR volume is not linear and is largest during the first weeks.

METHODS

Patients with colorectal liver metastases (CRLM) and standardized future liver remnant (sFLR) < 30% treated with PVO were prospectively included. All patients had at least one CT evaluation before radical hepatectomy.

RESULTS

Forty-eight patients were included. During the first week after PVO, the kinetic growth rate (KGR) was 5.4 (± 4), compared to 1.5 (± 2) between the first and second CT (p < 0.05). For patients reaching adequate FLR and therefore treated with radical hepatectomy, the KGR was 7 (± 4) the first week, compared to 4.3 (± 2) for patients who failed to reach a sufficient volume (p = 0.4). During the interval between the first and second CT, the KGR was 2.2 (± 2), respectively (± 0.1) (p = 0.017).

DISCUSSION

The increase in liver volume after PVO is largest during the first week. As KGR decreases over time, it is important to shorten the interval between PVO and the first volume evaluation; this may aid in decision-making and reduce unnecessary waiting time.

Preoperative Chemotherapy on Functional Liver Regeneration for Colorectal Liver Metastases Assessed With 99mTc-GSA SPECT/CT Imaging

Objective:

To investigate the functional liver regeneration after chemotherapy and liver resection for colorectal liver metastases (CRLM).

Background/Purpose:

Preoperative chemotherapy followed by liver resection for CRLM has been increasing; however, its negative impact on liver regeneration remains unknown.

Methods:

From January 2009 to December 2013, we enrolled 40 selected patients who underwent major hepatectomy without viral hepatitis and severe liver fibrosis. CRLM patients with preoperative chemotherapy (CT-CRLM group, n = 12) and patients without preoperative chemotherapy (control group, n = 28) were evaluated. Liver volume (LV) and functional liver volume (FLV) was assessed using Tc-99m–labeled galactosyl human serum albumin (99mTc-GSA) scintigraphy, single-photon emission computed tomography (SPECT), CT-fused images. Preoperative, future remnant liver, and post 1-month values were compared.

Results:

Median course of preoperative chemotherapy was 8 (range: 6–16). Preoperative background factors were almost identical including resection rate and functional resection rate. In the CT-CRLM group and in the control group, the percentage increases in LV were 39.3% ± 29.0% and 23.2% ± 23.5% (P = 0.037), and FLV were 79.4% ± 43.1% and 57.0% ± 33.4% (P = 0.417), respectively; absolute differences in LV were 216.2 ± 155.7 cm3 and 148.7 ± 134.7 cm3 (P = 0.086) and FLV were 19.4% ± 8.5%/m2 and 17.4% ± 7.9%/m2 (P = 0.235), respectively. We found no obvious tendency for negative influence on liver functional regeneration by the preoperative regimens for CRLM.

Conclusions:

Several courses of preoperative chemotherapy may not affect functional liver regeneration for CRLM patients after major hepatectomy.

Beyond the Knife: The Evolving Nonsurgical Management of Oligometastatic Colorectal Cancer

In patients with liver-limited oligometastatic disease, the goal of treatment can be curative intent. Historically, this was accomplished in patients presenting with upfront resectable disease. The availability of increasingly efficacious chemotherapy and biologic combinations with encouraging response rates led to the potential to convert unresectable disease to resectability. Beyond the backbone of surgery, we now have a portfolio of locoregional strategies to consider.From an interventional radiology perspective, the use of portal vein embolization can facilitate hypertrophy of the liver in anticipation of resection, thus converting unresectable disease to one amenable to a surgical approach with curative intent. Technological advances in liver-directed ablative therapies have afforded the possibility of eliminate radiographically evident disease with the hope for long-term disease control. Advanced radiotherapy techniques are further increasing the therapeutic options for patients with metastatic colorectal cancer. Improvements in external-beam radiotherapy over the past 2 decades include image-guided radiotherapy, intensity-modulated radiotherapy, stereotactic body radiotherapy, and proton-beam therapy. Finally, selective internal radiation therapy (SIRT) with microspheres labeled with the β-emitter ⁹⁰Y enable targeted delivery of radiation to hepatic tumors. A coordinated multidisciplinary approach is required to integrate these nonsurgical adjuncts in an evidence-based manner to optimize outcomes for patients with potentially resectable metastatic disease. In this article, we summarize recent developments in systemic therapy, radiotherapy, and interventional liver-directed therapies that have changed the treatment landscape for patients with oligometastatic colorectal cancer.

Neoadjuvant chemotherapy does not affect future liver remnant growth and outcomes of associating liver partition and portal vein ligation for staged hepatectomy

BACKGROUND

The only potentially curative treatment for patients with colorectal liver metastases is hepatectomy. Associating liver partition and portal vein ligation for staged hepatectomy has emerged as a method of treatment for patients with inadequate future liver remnant. One concern about associating liver partition and portal vein ligation for staged hepatectomy is that preoperative chemotherapy may negatively affect the volume increase of the future liver remnant and outcomes.

METHODS

This study from the International Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy Registry (NCT01924741) includes 442 patients with colorectal liver metastases registered from 2012-2016. Future liver remnant hypertrophy (absolute increase, percent increase, and kinetic growth rate) and clinical outcome were analyzed retrospectively in relation to type and amount of chemotherapy. The analyzed groups included patients with no chemotherapy, 1 regimen of chemotherapy, >1 regimen, and a group that received monoclonal antibodies in addition to chemotherapy.

RESULTS

Ninety percent of the patients received neoadjuvant oncologic therapy including 42% with 1 regimen of chemotherapy, 44% with monoclonal antibodies, and 4% with >1 regimen. Future liver remnant increased between 74-92% with the largest increase in the group with 1 regimen of chemotherapy. The increase in milliliters was between 241 mL (>1 regimen) and 306 mL (1 regimen). Kinetic growth rate was between 14-18% per week and was greatest for the group with 1 regimen of chemotherapy. No statistical significance was found between the groups with any of the measurements of future liver remnant hypertrophy.

CONCLUSION

Neoadjuvant chemotherapy, including monoclonal antibodies, does not negatively affect future liver remnant growth. Patients with colorectal liver metastases who might be potential candidates for associating liver partition and portal vein ligation for staged hepatectomy should be considered for neoadjuvant chemotherapy.

Impact of Bevacizumab on parenchymal damage and functional recovery of the liver in patients with colorectal liver metastases

Background

Little is known about the safety of the anti-VEGF antibody bevacizumab in patients undergoing resection for colorectal liver metastases (CLM). This meta-analysis evaluates the impact of bevacizumab on parenchymal damage and functional recovery in patients undergoing resection for CLM.

Methods

The Medline, Embase and Cochrane Library were systematically searched for studies on preoperative chemotherapy with and without bevacizumab prior to resection of CLM. Studies that reported histological and/or clinical outcomes were eligible for inclusion. Meta-analyses were performed using a random effects model.

Results

A total of 18 studies with a total sample size of 2430 patients (1050 patients with bevacizumab) were found. Meta-analyses showed a significant reduction in sinusoidal obstruction syndrome (SOS) (Odds ratio 0.50 [95 % confidence interval 0.37, 0.67]; p < 0.001; I² = 0 %) and hepatic fibrosis (0.61 [0.4, 0.86]; p = 0.004; I² = 7 %) after preoperative chemotherapy with bevacizumab. The reduced incidence of posthepatectomy liver failure in patients with bevacizumab treatment just failed to reach statistical significance (0.61 [0.34, 1.07]; p = 0.08 I² = 6 %). While there was no difference in perioperative morbidity and mortality, the incidence of wound complications was significantly increased in patients who received bevacizumab (1.81 [1.12, 2.91]; p = 0.02 I² = 4 %).

Conclusions

The combination of bevacizumab with cytotoxic chemotherapy is safe but increases the incidence of wound complications after resection of CLM. The reduction of SOS and hepatic fibrosis warrant further investigation and may explain the inverse association of bevacizumab administration and posthepatectomy liver failure.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2095-6) contains supplementary material, which is available to authorized users.

Portal vein embolization for induction of selective hepatic hypertrophy prior to major hepatectomy: rationale, techniques, outcomes and future directions

The ability to modulate the future liver remnant (FLR) is a key component of modern oncologic hepatobiliary surgery practice and has extended surgical candidacy for patients who may have been previously thought unable to survive liver resection. Multiple techniques have been developed to augment the FLR including portal vein embolization (PVE), associating liver partition and portal vein ligation (ALPPS), and the recently reported transhepatic liver venous deprivation (LVD). PVE is a well-established means to improve the safety of liver resection by redirecting blood flow to the FLR in an effort to selectively hypertrophy and ultimately improve functional reserve of the FLR. This article discusses the current practice of PVE with focus on summarizing the large number of published reports from which outcomes based practices have been developed. Both technical aspects of PVE including volumetry, approaches, and embolization agents; and clinical aspects of PVE including data supporting indications, and its role in conjunction with chemotherapy and transarterial embolization will be highlighted. PVE remains an important aspect of oncologic care; in large part due to the substantial foundation of information available demonstrating its clear clinical benefit for hepatic resection candidates with small anticipated FLRs.

Neoadjuvant and conversion treatment of patients with colorectal liver metastasis: the potential role of bevacizumab and other antiangiogenic agents

More than 50 % of patients with colorectal cancer develop liver metastases. Surgical resection is the only available treatment that improves survival in patients with colorectal liver metastases (CRLM). New antiangiogenic targeted therapies, such as bevacizumab, aflibercept, and regorafenib, in combination with neoadjuvant and conversion chemotherapy may lead to improved response rates in this population of patients and increase the proportion of patients eligible for surgical resection. The present review discusses the available data for antiangiogenic targeted agents in this setting. One of these therapies, bevacizumab, which targets the vascular endothelial growth factor (VEGF) has demonstrated good results in this setting. In patients with initially unresectable CRLM, the combination of 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX) plus bevacizumab has led to high response and resection rates. This combination is also effective for patients with unresectable CRLM. Moreover, the addition of bevacizumab to chemotherapy in the neoadjuvant setting of liver metastasis has a higher impact on pathological response rate. This drug also has a manageable safety profile, and according to recent data, bevacizumab may protect against the sinusoidal dilation provoked in the liver by certain cytotoxic agents. In phase II trials, antiangiogenic therapy has demonstrated benefits in the presurgical treatment of CRLM and may represent a new treatment pathway for these patients.

Impact of Neoadjuvant Chemotherapy on Hypertrophy of the Future Liver Remnant after Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy

BACKGROUND

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has been demonstrated as a feasible procedure in extended liver resections as a means of successfully increasing the volume of the future liver remnant (FLR). Neoadjuvant chemotherapy (CTx) is toxic to the organ and may impair hepatic regeneration. This study was performed to assess the procedure's effect on hypertrophy of the FLR, including the short-term survival.

STUDY DESIGN

We analyzed 19 consecutive ALPPS patients, of whom 58% (n = 11) received neoadjuvant CTx because of colorectal liver metastasis (CRM). Patients presented with multifocal CRM (n = 11, 58%); cholangiocarcinoma (n = 7, 37%), of which 5 were in the Klatskin position; and gallbladder carcinoma (n = 1, 5%). Hepatectomy was performed within 6 to 13 days after hepatic partition. Volumetry was performed before both liver partitioning and hepatectomy. A survival analysis was performed.

RESULTS

Liver partition and portal vein ligation induced sufficient hypertrophy of the FLR, with an increased volume of 74% ± 35%. Patients underwent hepatectomy after a median of 8 days; in all cases R0 resection was achieved. Neoadjuvant CTx was shown to significantly impair hypertrophy. The volume of the FLR in non-CTx patients increased by 98% ± 35%; an increase of 59% ± 22% was observed in patients who underwent CTx (p = 0.027). Chemotherapy did not have an impact on either morbidity or in-hospital mortality, which were 68% and 16%, respectively. One-year overall survival was 53%, with a 1-year survival of 67% in CRM patients and 38% in non-CRM patients (p > 0.05).

CONCLUSIONS

Data presented here demonstrate for the first time that neoadjuvant CTx significantly impairs hypertrophy of the FLR after ALPPS.

Colorectal cancer with potentially resectable hepatic metastases: optimizing treatment

Colorectal cancer is a common malignancy and often presents with synchronous or metachronous distant spread. For patients with hepatic metastases, resection is the principal curative option. Liberalization of the indications for hepatic resection has introduced a number of challenges related to the size, distribution, and number of metastases as well as the condition of the future liver remnant. Advances in systemic therapy have solidified its role as both an important adjunct to surgery and also for many patients as a mechanism to facilitate resection. In patients whose disease is marginally resectable as a consequence of the distribution of hepatic lesions that precludes complete resection or out of concern for the future liver remnant, a number of strategies have been advocated, including prehepatectomy systemic therapy, staged surgical approaches, ablative technologies, and preoperative portal vein embolization. It is the purpose of this review to discuss ways in which to optimize the treatment of patients with potentially resectable disease, specifically those who are judged to have "borderline" resectable situations.

The Influence of Aging on Hepatic Regeneration and Early Outcome after Portal Vein Occlusion: A Case-Control Study

BACKGROUND

Portal vein occlusion (PVO) is used to increase inadequate future liver remnant volume (FLRV). Impaired liver regeneration has been reported in aged animals. This study was designed to evaluate the impact of patient age on hepatic regeneration.

METHODS

Sixty patients aged ≥70 years were matched 1:1 with 60 patients aged <70 years. Matching criteria were sex, diabetes, cirrhosis, pre-PVO chemotherapy and bevacizumab administration, and jaundice.

RESULTS

The median ages in the older and younger groups were 76 (range 70-83) years and 59 (range 20-69) years, respectively (p < 0.001). Median FLRV following PVO (33.1 ± 6.8 vs. 31.9 ± 6.0 %) and volumetric increase (0.52 ± 0.35 vs. 0.49 ± 0.34) were similar in the two groups. Of the older and younger patients, 10 % and 1.7 %, respectively, did not undergo liver surgery after PVO (p = 0.051). Mortality (5.5 vs. 6.7 %) and major morbidity (25.9.8 vs. 22 %) rates were similar. Liver failure rate was higher in older patients (35.1 vs. 16.9 %, p < 0.026), mainly due to Grade A liver failure (20.3 vs. 8.4 %, p < 0.001). Multivariate analysis showed that age ≥ 70 years [odds ratio (OR) 3.03; 95 % confidence interval (CI) 1.18-7.78; p = 0.020] and biliary cancer diagnosis (OR 4.69; 95 % CI 1.81-12.09; p = 0.001) were independent risk factors for postoperative liver failure.

CONCLUSIONS

Liver regeneration after PVO is not impaired by age. Nevertheless, liver resection in elderly patients is performed less often after PVO and carries a higher risk of liver failure.

Combination therapy with sorafenib and radiofrequency ablation for BCLC Stage 0-B1 hepatocellular carcinoma: a multicenter retrospective cohort study

OBJECTIVES

The objective of this study was to evaluate the efficacy of combined therapy using Sorafenib and radiofrequency ablation (RFA) with curative intent for all detectable lesions in patients with Barcelona Clinic Liver Cancer (BCLC) Stage 0-B1 hepatocellular carcinoma (HCC).

METHODS

One hundred and twenty-eight patients with HCC from 12 centers were enrolled in this retrospective study; 64 patients who received Sorafenib plus RFA (Sorafenib-RFA) were compared with a control group treated with RFA alone. The two patient groups were selected with a predefined criterion and matched in terms of their clinical and tumor characteristics at baseline. The primary end point of the study was the incidence of post-RFA HCC recurrence. Secondary end points were overall survival (OS) and treatment toxicity.

RESULTS

During a median follow-up of 134.1 weeks, 49 patients died and 79 survived. The 1-, 2-, and 3-year cumulative incidences of post-RFA recurrence were 40.5%, 62.9%, and 74.5%, respectively, in the Sorafenib-RFA group, and 62.8%, 85.4%, and 92.7%, respectively, in the RFA group. The 1-, 2-, 3-, and 4-year OS rates were 85.6%, 64.0%, 58.7%, and 50.3%, respectively, in the Sorafenib-RFA group, and 80.7%, 47.2%, 30.9%, and 30.9%, respectively, in the RFA group. Thus, the Sorafenib-RFA group exhibited better survival than the RFA alone group.

CONCLUSIONS

Combined therapy with Sorafenib-RFA was associated with a lower incidence of post-RFA recurrence and better OS than RFA alone in patients with BCLC Stage 0-B1 HCC. Although these findings suggest that Sorafenib and RFA is safe and effective for the treatment of early HCC, prospective and randomized controlled trials are needed to validate them.

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS): a new strategy to increase resectability in liver surgery

BACKGROUND

Partial hepatectomy with clear surgical margins is the main curative treatment for hepatic malignancies. The safety of liver resection, to a great extent, depends on the volume of future liver remnant. This manuscript reviews some important strategies that have been developed to increase resectability for patients with borderline volume of future liver remnant, particularly associating liver partition and portal vein ligation for staged hepatectomy (ALPPS).

METHODS

To identify potentially relevant articles, we searched Medline and PubMed from January 2010 to December 2013 using the keywords "Associating liver partition and portal vein ligation for staged hepatectomy", "ALPPS", "portal vein embolization", "future liver remnant", "liver hypertrophy", and "liver failure". A number of references from the key articles were also cited. There were no exclusion criteria for published information to the topics.

RESULTS

Portal vein ligation (PVL) or embolization (PVE) are traditional approaches to induce liver hypertrophy of the future liver remnant (FLR) prior to hepatectomy in primarily non-resectable liver tumors. However, about 14 percent of patients fail to this approach. Adequate hypertrophy of the FLR using PVL or PVE generally takes more than four weeks. ALPPS can induce rapid growth of the FLR, which is more effective than by portal vein embolization or occlusion alone. Reportedly, the hypertrophy extent of FLR was 40%-80% within 6-9 days in contrast to approximately 8%-27% within 2-60 days by PVL/PVE. However, ALPPS was reported to have high operative morbidity (16%-64% of patients), mortality (12%-23% of patients) and bile leakage rates. Bile leakage and sepsis remain a major cause of morbidity, and the main cause of mortality includes hepatic insufficiency.

CONCLUSION

ALPPS has emerged as a new strategy to increase resectability of hepatic malignancies. Due to high morbidity and mortality rates of ALPPS procedure, the surgical candidates should be selected carefully. Moreover, there are very limited available evidence for its technical feasibility, safety and oncological outcome which are needed for further evaluation in larger scale of studies.

Efficacy and safety of portal vein embolization for two-stage hepatectomy in patients with colorectal liver metastasis

PURPOSE

To examine the efficacy and safety of portal vein embolization (PVE) when used during two-stage hepatectomy for bilobar colorectal liver metastases (CLM).

MATERIALS AND METHODS

PVE was performed as an adjunct to two-stage hepatectomy in 56 patients with CLM. Absolute future liver remnant (FLR) volumes, standardized FLR ratios, degree of hypertrophy (DH), and complications were analyzed. Segment II and III volumes and DH were also measured separately. All volumetric measurements were compared with a cohort of 96 patients (n = 37 right portal vein embolization [RPVE], n = 59 right portal vein embolization extended to segment IV portal veins [RPVE+4]) in whom PVE was performed before single-stage hepatectomy.

RESULTS

For patients who completed RPVE during two-stage hepatectomy (n = 17 of 17), mean absolute FLR volume increased from 272.1 cm(3) to 427.0 cm(3) (P < .0001), mean standardized FLR ratio increased from 0.17 to 0.26 (P < .0001), and mean DH was 0.094. For patients who completed RPVE+4 during two-stage hepatectomy (n = 38 of 39), mean FLR volume increased from 288.7 cm(3) to 424.8 cm(3) (P < .0001), mean standardized FLR increased from 0.18 to 0.26 (P < .0001), and mean DH was 0.083. DH of the FLR was not significantly different between two-stage hepatectomy and single-stage hepatectomy. Complications after PVE occurred in five (8.9%) patients undergoing two-stage hepatectomy.

CONCLUSIONS

PVE effectively and safely induced a significant DH in the FLR during two-stage hepatectomy in patients with CLM.

Evaluation and management of hepatic injury induced by oxaliplatin-based chemotherapy in patients with hepatic resection for colorectal liver metastasis

Patients with colorectal liver metastasis (CRLM) can be cured with surgical resection. Recent advances in systemic chemotherapy, including molecular target agents, can be used to introduce "conversion surgery" and achieve R0 resection even in patients with initially unresectable CRLM. Furthermore, neoadjuvant chemotherapy also tries to be applied in patients with resectable CRLM to maximize the remnant liver and reduce the residual micrometastasis before surgery. The development of chemotherapy-induced hepatic injuries is increasingly being recognized, including sinusoidal obstructive syndrome (SOS), steatosis, steatohepatitis and biliary sclerosis. Especially, oxaliplatin (L-OHP)-based chemotherapy in clinical settings appears to be primarily associated with SOS. Various reports have tried to demonstrate the rationale of the correlation between L-OHP-based chemotherapy and SOS for the following hepatic surgery. While we can recognize that this pathophysiological disadvantage leads to hepatic dysfunction and the increasing postoperative morbidity, the essential part of this problem including clinical disadvantage, onset mechanism, evaluation systems, and targeted agents for prevention and treatment of SOS continue to be unclear. In this review, we summarize the current experience with hepatic injury induced by L-OHP-based chemotherapy, focusing on SOS-based on clinical and experimental data, in order to assist in the resolution of these identified factors. Finally, the need for reliable methods to identify the risk of SOS, to evaluate SOS status and to predict the safety of surgical treatment in patients with chemotherapy prior to surgery will be emphasized.

Tumour progression and liver regeneration--insights from animal models

Surgery remains the only curative treatment for colorectal liver metastases. For patients with multiple bilobar spread, extended hepatectomy might be required to achieve complete margin-free resection. In such cases, portal vein occlusion has been developed to induce preoperative hypertrophy of the future remnant liver and increase the resectability rate. Evidence now suggests that liver regeneration after hepatectomy and portal vein occlusion has a protumorigenic role, either through an upregulation of growth factors and cytokines or by haemodynamic changes in the blood supply to the liver. Experimental studies have reported a stimulatory effect of liver regeneration on the tumoral volume of liver metastases and on the metastatic potential of cells engrafted in the liver; this effect seems to depend on the timing of hepatectomy and portal vein occlusion. However, the variability of animal tumour models that are used for research in experimental colorectal liver metastases might account for some of the inconsistent and conflicting results. This Review presents clinical and experimental data pertaining to whether liver regeneration causes proliferation of tumour cells. We also analyse the different animal models of colorectal liver metastases in use and discuss current controversies in the field.

Limiting factors for liver regeneration after a major hepatic resection for colorectal cancer metastases

BACKGROUND

Chemotherapy before resection of colorectal metastases in the liver is extensively used and has been shown to induce histopathological changes in the liver parenchyma, although little is known about the effect of chemotherapy on liver regeneration. The aim of this study was to determine if pre-operative chemotherapy influences the regenerated liver volume after a major liver resection.

PATIENTS AND METHODS

This retrospective cohort study included 74 patients subjected to a major liver resection for colorectal metastases. Patients were divided into two groups depending on whether they had been treated with chemotherapy less than 3 months before surgery or not. Liver volumes were measured before and 1 year after resection.

RESULTS

Pre-operative chemotherapy reduced volumetric liver regeneration (83 ± 2% versus 91 ± 2%; P = 0.007) as compared with patients without chemotherapy. There was a linear correlation between regenerated volume and time interval between the end of chemotherapy to resection (P = 0.031).

CONCLUSIONS

Pre-operative chemotherapy in patients with colorectal liver metastases negatively affects volume regeneration after a partial hepatectomy. The time interval between chemotherapy and surgery determines the impact of these affects.

Determining timing of hepatectomy for colorectal cancer with distant metastasis according to imaging-based tumor shrinkage ratio

BACKGROUND

The optimal timing of surgical resection of liver metastasis remains controversial, and guidelines regarding the upper limits of operative indications have not yet been defined. Surgical indication for metastasis from colorectal cancer (CLM) based on results of preoperative chemotherapy and RNF8 was investigated.

METHODS

Differences in CLM size on CT were evaluated as shrinkage rate/day by dividing tumor shrinkage rates by the interval in days between CT. Levels of RNF8 of resected colorectal cancer and CLM frozen specimen were detected.

RESULTS

When the cut line for shrinkage rate at 12 weeks was set at 0.35%, disease-free survival was significantly better in patients with a shrinkage rate >0.35% vs. ≤0.35% (p=0.003). RNF8 expression was significantly higher in Tis (p=0.001). In liver metastasis, RNF8 expression level was significantly lower in patients with partial response to FOLFOX than with stable disease, (p=0.017).

CONCLUSIONS

A strategy of FOLFOX administration for 12 weeks to patients with low RNF8 expression and hepatectomy planned after 4 weeks rest may be accepted as the best therapeutic option for treating CLM.

[Microenvironment and colorectal liver metastases angiogenesis: surgical implications]

Stephen Paget's proposed an original "seed and soil" theory, with organ-preference patterns of tumor metastasis resulting in interaction between metastatic tumor cells and their specific microenvironment. There is many experimental and clinical data showing that this theory is validated. More recently, it has been suggested that early changes in the microenvironment at the distant sites, could be induced by the primary tumor, reported as "pre-metastatic niche" formation. Tumor cells could produce growth factors, cytokines which could facilitate the recruitment and the mobilization of the bone marrow-derived endothelial progenitor cells, and thus necessary for the tumor neovascularization and metastasis growth. Although the clinical value of the concept of the premetastatic niche is not yet elucidated, these data could encourage surgeons to perform the colorectal surgery first and then the liver surgery, in patients with synchronous colorectal liver metastases. The reciprocal interactions between primary tumor and microenvironment at the distant sites are therefore determinant for tumor progression. Taken together, the microenvironment is an important therapeutic target and surgeons and oncologist could discuss the choice of different surgical strategy for patient with synchronous colorectal liver metastases regarding the interaction with the microenvironment affected by primary tumor resection.

Safety of liver resection for hepatocellular carcinoma after sorafenib therapy: a multicenter case-matched study

BACKGROUND

Liver resection can be considered in some hepatocellular carcinoma (HCC) patients who received sorafenib. The lack of clinical data about safety of resection after sorafenib treatment led us to assess its potential impact on perioperative course in a multicentric study.

METHODS

From 2008 to 2011, a total of 23 HCC patients who underwent liver resection after treatment with sorafenib (sorafenib group) were compared with 46 HCC patients (control group) matched for age, gender, underlying liver disease, tumor characteristics and type of resection. Patients received sorafenib for a median duration of 1 (range 0.2-11) months and drug was interrupted at least 7 days before surgery. End points were intraoperative (operative time, vascular clamping, blood loss and transfusion), and postoperative outcomes focusing on recovery of liver function.

RESULTS

In the sorafenib group, HCC was developed on F4 cirrhosis in 48 % and the rate of major resection was 44 %. Surgical procedure duration (280 vs. 240 min), transfusion rate (26 vs. 15 %), blood loss (400 vs. 300 mL) and vascular clamping (70 vs. 74 %) were similar in the two groups. Mortality was zero in the sorafenib group and one (2.1 %) in the control group (p = 1.000). The incidence of postoperative complications was 44 % in the sorafenib group and 59 % in the control group (p = 0.307). Recovery of liver function was similar in the two groups in terms of prothrombin time (90 vs. 81 %, p = 0.429) and bilirubin level (16 vs. 24 μmol/L, p = 102) at postoperative day 5.

CONCLUSIONS

No adverse effect of preoperative administration of sorafenib was observed during and immediately after liver resection for HCC.

The ALPPS technique for bilateral colorectal metastases: three "variations on a theme"

The aim of this study was to assess feasibility of technical variations of the associating liver partition and portal vein ligation for staged hepatectomy technique (ALPPS) with regard to three different ways of liver splitting. The ALPPS technique was applied in the classic form consisting in ligation of the right portal vein, limited resections on the left lobe and splitting along the umbilical fissure; the right lobe was removed 1 week later. The first variation was "left ALPPS": ligation of the left portal vein, multiple resections on the right hemiliver and splitting along the main portal fissure. The second variation was "rescue ALPPS", consisting in simple splitting of the liver along the main portal fissure several months after a radiological portal vein embolization that did not allow satisfactory liver hypertrophy. The third variation was "right ALPPS", consisting in ligation of the posterolateral branch of right portal vein, left lateral sectionectomy, multiple resections on the right anterior and left medial section and splitting along the right portal fissure. In all cases auxiliary deportalized liver was removed 1 week later. 4 patients with colorectal metastases were included. Morbidity was defined according to the Clavien-Dindo classification: grade I (2 events), grade IIIb (1 event). Postoperative mortality was nil. Median follow-up was 4 months and to date all patients are still alive. ALPPS technique, in its "classical" and modified forms, is a good option for selected patients with bilateral colorectal metastases and represents a feasible alternative to classical two-stage hepatectomy.

Interventional oncologic approaches to liver metastases

Metastatic liver disease is the most common cause of death in cancer patients. Complete surgical resection is currently considered the only curative treatment, with only about 25% of patients being amenable to surgery. Therefore, a variety of interventional oncologic techniques have been developed for treating secondary liver malignancies. The aim of these therapies is either to allow patients with unresectable tumors to become surgical candidates, provide curative treatment options in nonsurgical candidates, or improve survival in a palliative or even curative approach. Among these interventional therapies are transcatheter therapies such as portal vein embolization, hepatic artery infusion chemotherapy, transarterial chemoembolization, and radioembolization, as well as interstitial techniques, particularly radiofrequency ablation as the most commonly applied technique. The rationale, application and clinical results of each of these techniques are reviewed on the basis of the current literature. Future prospects such as gene therapy and immunotherapy are introduced.

Preoperative administration of bevacizumab is safe for patients with colorectal liver metastases

AIM: To assess the impact of preoperative neoadjuvant bevacizumab (Bev) on the outcome of patients undergoing resection for colorectal liver metastases (CLM).

METHODS: Eligible trials were identified from Medline, Embase, Ovid, and the Cochrane database. The data were analyzed with fixed-effects or random-effects models using Review Manager version 5.0.

RESULTS: Thirteen nonrandomized studies with a total of 1431 participants were suitable for meta-analysis. There was no difference in overall morbidity and severe complications between the Bev + group and Bev - group (43.3% vs 36.8%, P = 0.06; 17.1% vs 11.4%, P = 0.07, respectively). Bev-related complications including wound and thromboembolic/bleeding events were also similar in the Bev + and Bev - groups (14.4% vs 8.1%, P = 0.21; 4.1% vs 3.8%, P = 0.98, respectively). The incidence and severity of sinusoidal dilation were lower in patients treated with Bev than in patients treated without Bev (43.3% vs 63.7%, P < 0.001; 16.8% vs 46.5%, P < 0.00, respectively).

CONCLUSION: Bev can be safely administered before hepatic resection in patients with CLM, and has a protective effect against hepatic injury in patients treated with oxaliplatin chemotherapy.

Reappraisal of the risks and benefits of major liver resection in patients with initially unresectable colorectal liver metastases

OBJECTIVES

To determine short- and long-term outcomes of major hepatectomy in patients with downstaged colorectal liver metastases considered initially unresectable (IU).

BACKGROUND

Improvements in both surgical technique and efficacy of chemotherapy have increased the rate of resection for IU colorectal liver metastases. The outcome of these patients needs to be reassessed.

PATIENTS AND METHODS

From 2000 to 2011, 257 patients underwent major hepatectomy for colorectal liver metastases. Of these, 87 (34%) IU patients required portal vein occlusion after chemotherapy downstaging. Patients requiring less than 12 cycles and 12 or more cycles of chemotherapy before resection were defined as fast responders and slow responders, respectively.

RESULTS

Compared with fast responders, slow responders had increased mortality (0% vs 19%, P = 0.003) and major morbidity rates (20% vs 55%, P < 0.001) despite almost identical tumor characteristics and similar procedures. In multivariate analysis, the only factor associated with increased major morbidity was the existence of a number of chemotherapy cycles of 12 or more (hazard ratio [HR]: 5.32, confidence interval [CI]: 1.69-16.7, P = 0.004). One-, 3-, and 5-year disease-free survival rates for the entire population were 48%, 17.5%, and 13%, respectively. Multivariate analysis found that slow responders (HR: 2.89, CI: 1.67-5.04, P < 0.001) and patients without adjuvant chemotherapy (HR: 2.38, CI: 1.33-4.35, P = 0.004) had a significantly decreased disease-free survival. All slow responders postoperatively recurred within 3 years.

CONCLUSIONS

Liver resection in slow responders, that is, IU patients requiring 12 or more chemotherapy cycles and portal vein occlusion to achieve resectability, is associated with poor short- and long-term outcomes. These patients would probably benefit from more conservative strategies.

Volumetric analysis of remnant liver regeneration after major hepatectomy in bevacizumab-treated patients: a case-matched study in 82 patients

BACKGROUND

The objective was to determine the liver regeneration capacity and morbidity and mortality rates after major hepatectomy for colorectal metastases in patients having undergone bevacizumab-based chemotherapy (bev+).

PATIENTS AND METHODS

Between 2006 and 2011, 41 patients underwent major hepatectomy within 3 months of bevacizumab and were matched with 41 patients operated on following systemic chemotherapy without bevacizumab (bev-). The matching criteria were the following: number of courses of chemotherapy, chemotherapy-free interval, age, and type of hepatectomy. After measurements of remnant liver volume (RLV) preoperatively and at 1 month (RLV1M), volumetric gain was calculated as absolute (RLV1M-RLV) or relative regeneration [(RLV1M-RLV/RLV)]. Ninety-day morbidity was rated according to the Clavien-Dindo classification.

RESULTS

There were 21 right, 9 extended right, and 11 left hepatectomies in each group. Groups were comparable in terms of matching criteria, body mass index, American Society of Anesthesiologists score, and RLV. No mortalities were observed. There were no intergroup differences in overall morbidity (56% in bev+ vs 34.1%; P = 0.075) or postoperative liver failure. A severe complication occurred in 5 bev+ (4 eviscerations) and 4 bev- (bile leakages) (P = 0.95). The median hospital stay was similar in both groups as were the degrees of absolute and relative liver regeneration (143% in bev+ vs 114%; P = 0.20). Liver regeneration was not influenced by the type of hepatectomy, the number of courses of chemotherapy, or age more than 65 years.

CONCLUSIONS

In a methodologically robust trial in the largest cohort reported up to date, bevacizumab did not impair liver regeneration after major hepatectomy-even in elderly patients or those with high exposure to chemotherapy.

Multimodal management of colorectal liver metastases and the effect on regeneration and outcome after liver resection

Management of colorectal liver metastases (CRLM) has dramatically changed during the last decade and has now become more multimodal and aggressive, including the use of downstaging chemotherapy, portal vein embolization to increase the function of the liver remnant or both in combination. Radiofrequency ablation is also an option in CRLM, potentially combined with surgical resection. Results are quite convincing concerning the safety of liver resection also when performed following neoadjuvant chemotherapy. Sparing liver parenchyma in patients with bilobar liver metastatic disease subjected to liver resection may be possible without endangering surgical radicality. Sparing liver parenchyma when using neoadjuvant chemotherapy, a chemotherapy-free period of 6 weeks or more seems to positively affect liver regeneration. There is still the possibility to reresect recurrent liver lesions, though there seems to be a tendency toward fewer reresections following the use of adjuvant chemotherapy.

Surgical results after downstaging of initially marginal or non-resectable liver metastases

Surgery remains the best curative treatment for resectable patients with colorectal liver metastases. In patients initially considered unresectable, both refinements in surgical technique using portal vein occlusion or two-step resections and increased efficiency of chemotherapy regimen with the adjunction of antiangiogenics now allow secondary resection. Recent evidence suggests almost identical long-term survival in case of secondary downstaged lesions advocating an aggressive approach. However, these data lie on disparate and nonconsensual criteria for unresectability, which often do not gather technical and oncologic components together. Furthermore, both impaired general status and damaged underlying parenchyma as a consequence of prolonged chemotherapy to achieve resectability as well as the technical challenge required to perform adequate carcinologic resection could increase the operative risk in such patients. In our experience, a subgroup of slow chemo-responding initially unresectable patients who required preoperative liver volume modulation after ≥ 12 cycles of chemotherapy to achieve sufficient response experienced dramatically high operative risk which jeopardized postoperative chemotherapy and subsequently put these patients at increased risk of recurrence. Whether all patients preoperatively amenable to surgery using intensive chemotherapy and complex surgical strategy actually benefit from such an aggressive approach is a matter of ongoing debate, which needs a reappraisal.

VEGF levels and the angiogenic potential of the microenvironment can affect surgical strategy for colorectal liver metastasis

The hypotheses emerging from basic research on colorectal liver metastases must be tested in clinical situations for the adaptation of current treatment strategies. Pre-metastatic niches have been shown to exist in human colorectal synchronous metastases, with the liver parenchyma adjacent to the synchronous liver metastases providing a favorable, angiogenic environment for metastatic tumor growth. The role of the VEGF signaling pathway in liver regeneration and tumor growth remains unclear, but the use of antiangiogenic agents in combination with surgical treatment is almost certainly beneficial.

Surgical options for initially unresectable colorectal liver metastases

Although the frontiers of liver resection for colorectal liver metastases have broadened in recent decades, approximately 75% of these patients present with unresectable metastases at the time of their diagnosis. In the past, these patients underwent only palliative treatment, without the chance of a cure. In the previous two decades, several therapeutic strategies have been developed that render resectable those metastases that were initially unresectable, thus offering the chance of long-term survival and even a cure to these patients. The oncosurgical modalities that are available include liver resection following portal vein ligation/embolization, “two-stage” liver resection, one-stage ultrasonically guided liver resection, hepatectomy following conversion chemotherapy, and liver resection combined with thermal ablation. Moreover, in recent years, certain authors have recommended the revisiting of the concept of liver transplantation in highly selected patients with unresectable colorectal liver metastases and favorable prognostic factors. By employing such therapies, the number of patients with colorectal liver metastases who undergo a potentially curative treatment could increase to 40%. The safety profile of these approaches is acceptable (morbidity rates as high as 45%, mortality rates of less than 5%). Furthermore, the 5-year survival rates (approximately 30%) are significantly increased over those that were achieved with palliative treatment.

Portal vein embolization stimulates tumour growth in patients with colorectal cancer liver metastases

OBJECTIVES

Portal vein embolization (PVE) can facilitate the resection of previously unresectable colorectal cancer (CRC) liver metastases. Bevacizumab is being used increasingly in the treatment of metastatic CRC, although data regarding its effect on post-embolization liver regeneration and tumour growth are conflicting. The objective of this observational study was to assess the impact of pre-embolization bevacizumab on liver hypertrophy and tumour growth.

METHODS

Computed tomography scans before and 4 weeks after PVE were evaluated in patients who received perioperative chemotherapy with or without bevacizumab. Scans were compared with scans obtained in a control group in which no PVE was administered. Future liver remnant (FLR), total liver volume (TLV) and total tumour volume (TTV) were measured. Bevacizumab was discontinued ≥ 4 weeks before PVE.

RESULTS

A total of 109 patients and 11 control patients were included. Portal vein embolization induced a significant increase in TTV: the right lobe increased by 33.4% in PVE subjects but decreased by 34.8% in control subjects (P < 0.001), and the left lobe increased by 49.9% in PVE subjects and decreased by 33.2% in controls (P= 0.022). A total of 52.8% of the study group received bevacizumab and 47.2% did not. There was no statistical difference between the two chemotherapy groups in terms of tumour growth. Median FLR after PVE was similar in both groups (28.8% vs. 28.7%; P= 0.825).

CONCLUSIONS

Adequate liver regeneration was achieved in patients who underwent PVE. However, significant tumour progression was also observed post-embolization.

Tumor and non-tumor liver angiogenesis is traced and evaluated by hepatic arterial ultrasound in murine models

We studied the relationships between hepatic and mesenteric mean blood-flow velocities (mBFVs) measured by ultrasound imaging and (1) downstream tumor angiogenesis during liver metastasis induced by spleen injection of LS174 human colon cells overexpressing the antiangiogenic Netrin4 (LS174-NT4) or not (LS174-WT) and (2) downstream normal angiogenesis during hepatic regeneration after 50% hepatectomy. Liver volume and mBFVs were measured before and after surgery, at day 30 in the first model and at days 2, 7 and 16 in the second model. LS174-NT-4 vs. LS174-WT mice presented fewer metastases (25% vs. 90%, p < 0.001) and decreased hepatic mBFVs (16.5 ± 0.8 vs. 21.8 ± 1.4 cm s(-1), p < 0.01), without difference in mesenteric mBFVs. After partial hepatectomy, hepatic and mesenteric mBFVs increased at day 7, from 12.4 ± 1.7 and 11.8 ± 2.6 to 19.1 ± 1.8 and 17.5 ± 2.4 cm s(-1), respectively, (p < 0.01) then returned to baseline as liver volume. Duplex Doppler ultrasonography reliably assesses normal or tumor angiogenesis and may provide follow-up functional evaluation.

Impact of preoperative targeted therapy on postoperative complications after resection of colorectal liver metastases

PURPOSE

The impact of chemotherapy (CTx) on morbidity after liver resection for colorectal metastases (CRC-LM) has been increasingly investigated during recent years. Biologic agents like bevacizumab (BEV) or cetuximab (CET) are now added as "targeted therapy" (TT), also in neoadjuvant settings. Initial series could demonstrate the safety of those regimens in liver resection but data are still scarce. We evaluated the impact of CTx with BEV or CET (CTx + TT) on perioperative morbidity and mortality.

METHODS

Two hundred thirty-seven patients who underwent liver resections for CRC-LM after chemotherapy before surgery since 1999 were included. One hundred eighty-five patients (78%) had preoperative CTx regimen without biologic agents (fluoropyrimidine-, oxaliplatin-, or irinotecan-based) and 52 (22%) had CTx + TT (39 BEV, 11 CET, 2 CET/BEV). After preoperative CTx + TT, a time interval of at least 4-6 weeks and a residual liver volume of >35% before surgery were required.

RESULTS

Hemihepatectomy or more was performed in about half of the patients. The median amount of intraoperatively transfused blood was 0 ml in both groups (p = 0.34). Overall mortality was 1.7% and slightly elevated in patients with CTx + TT (3.8% vs. 1.1%, p = 0.17). Any complication occurred in (CTx + TT vs. CTx) 52% and 46%, respectively (p = 0.47). The rates of liver failure (9.6% vs. 9.7%, p = 0.98), infectious complications such as wound infection (19% vs. 16%, p = 0.62) and abdominal abscess (8% vs. 6.5%, p = 0.71), as well as the rate of relaparotomies (11.5% vs. 7.0%, p = 0.29) showed no significant differences between the groups with TT or without. In multivariate analyses, neither type nor duration of CTx nor the time interval between CTx and surgery showed any influence on complication rates.

CONCLUSIONS

Our data confirm the safety of targeted therapy before liver resection for CRC-LM. This effect may in part be due to our treatment policy (time interval to resection and residual liver volume) after intensive preoperative CTx.

Portal vein occlusion before major hepatectomy in patients with colorectal liver metastases: rationale, indications, technical aspects, complications and outcome

Surgery is the only curative treatment for colorectal liver metastases (CRLM), but resection should be total with tumor-free margins and the remaining parenchyma, functionally evaluated. The rationale behind portal vein embolization (PVE) to reduce the risk of these hepatic resections is threefold: (i) surgery for CRLM has become more and more aggressive, and hepatocellular insufficiency represents the leading cause of mortality after major hepatectomy for hepatic metastasis (HM), (ii) underlying hepatic disease occurs more frequently than previously thought in these patients having undergone neoadjuvant chemotherapy, and can alter hepatic function and/or hinder postoperative regeneration, and (iii) the operative risk is increased if major hepatectomy is associated with resection of the primary tumor. The goal of this update is to review the reasons behind and the indications for PVE, to analyze the literature pertaining to whether PVE should be routine or selective, and to tackle certain technical aspects, all within the framework of the treatment of CRLM.

[Intra-arterial treatment of liver metastases from colorectal carcinoma]

Colorectal carcinoma is a major public health concern with its yearly mondial incidence of about one million cases and yearly mortality of 500,000 cases. The liver is the organ most frequently affected by metastases with a frequency of 40 to 60% (contemporaneous in 25% of cases). While surgical resection is the only curative therapy, many patients are not such candidates due to the infiltrative nature of the liver metastases. Systemic chemotherapy and biotherapy regimens are the conventional treatment options for patients with multiple liver metastases. Under such circumstances, intra-arterial therapy may play a major role. We will review the main types of endovascular therapies for liver metastases from colorectal carcinoma including indications, results and potential complications.

Liver resection for advanced or aggressive colorectal cancer metastases in the era of effective chemotherapy: a review

Liver surgery has been known to cure metastatic colorectal cancer in a small proportion of patients. However, advances in procedural technique and chemotherapy now allow more patients to have safe, potentially curative surgery. Here we review surgery for unresectable colorectal liver metastases using an expert multidisciplinary approach. With multidisciplinary management of patients with effective chemotherapy that can downstage metastases, more patients with previously inoperable disease can benefit from surgery. Portal vein embolization results in hypertrophy of the future liver remnant; on occasions, combining embolization with staged liver resection permits potentially curative surgery for patients previously unable to survive resection. However, increasing use of chemotherapy has raised awareness of potential hepatotoxicity and other deleterious effects of cytotoxic agents. Prolonged prehepatectomy chemotherapy therefore can reduce resectability even using a 2-stage procedure. Suitable timing of surgery for unresectable liver metastases during chemotherapy is critical. Because of advances in chemotherapy, colorectal cancer, like ovarian cancer, can now show survival benefit from maximum surgical debulking. Benefit from such maximum hepatic debulking surgery for metastatic colorectal disease is uncertain, but likely. Surgery in isolation may be approaching technical limits, but is now likely to help more patients because of the success of complementary strategies, particularly newer chemotherapy and targeted therapy. Expert individualized multidisciplinary treatment planning and problem-solving is essential.

Colorectal liver metastases

The diagnosis and management of CRLM is complex and requires a multidisciplinary team approach for optimal outcomes. Over the past several decades, the 5-year survival following resection of CRLM has increased and the criteria for resection have broadened substantially. Even patients with multiple, bilateral CRLM, previously thought unresectable, may now be candidates for resection. Two-stage hepatectomy, repeat curative-intent hepatectomy, and even selected resection of extrahepatic metastases have further increased the number of patients who may be treated with curative intent. Multiple liver-directed therapies exist to treat unresectable, incurable patients with adequate survival benefit and morbidity rates.

Biologic modulation of chemotherapy in patients with hepatic colorectal metastases: the role of anti-VEGF and anti-EGFR antibodies

In the treatment of metastatic colorectal cancer, the subset of patients with liver-only metastases shows the greatest promise for prolonged survival and cure. Advances in surgery and medical treatment have encouraged multimodality treatment strategies and therefore require a true multidisciplinary approach. The current standard of care includes peri-operative chemotherapy and surgery. The new era of biologically targeted therapy requires an in-depth look at the possible efficacy and risks of adding these agents to the treatment protocol.