Extended liver venous deprivation before major hepatectomy induces marked and very rapid increase in future liver remnant function

Transfemoral hepatic vein catheterization reduces procedure time in double vein embolization

BACKGROUND

Double vein embolization with simultaneous embolization of the portal and hepatic vein aims to grow the future liver remnant in preparation for major hepatectomy. Transvenous hepatic vein embolization is usually done via a transjugular access. The purpose of this study is to describe the transfemoral approach as an alternative option and to discuss potential advantages.

RESULTS

Twenty-three patients undergoing hepatic vein embolization via a transjugular (n = 10) or transfemoral access (n = 13) were evaluated retrospectively. In all cases the portal vein embolization was done first. All procedures were technically successful. There were no peri-interventional complications. Only two patients were not able to proceed to surgery. Standardized future liver remnant hypertrophy was non-inferior with the transfemoral approach compared to the transjugular route. Procedure time was significantly shorter in the transfemoral access group (40 ± 13 min) compared to the transjugular group (67 ± 13 min, p < 0.001).

CONCLUSION

Transfemoral hepatic vein embolization is feasible, safe, and faster due to easier catheterization, improved stability, and simpler patient preparation. These findings will need to be validated in larger studies.

Image-guided percutaneous strategies to improve the resectability of HCC: Portal vein embolization, liver venous deprivation, or radiation lobectomy?

Despite considerable advances in surgical technique, many patients with hepatic malignancies are not operative candidates due to projected inadequate hepatic function following resection. Consequently, the size of the future liver remnant (FLR) is an essential consideration when predicting a patient's likelihood of liver insufficiency following hepatectomy. Since its initial description 30 years ago, portal vein embolization has become the standard of care for augmenting the size and function of the FLR preoperatively. However, new minimally invasive techniques have been developed to improve surgical candidacy, chief among them liver venous deprivation and radiation lobectomy. The purpose of this review is to discuss the status of preoperative liver augmentation prior to resection of hepatocellular carcinoma with a focus on these three techniques, highlighting the distinctions between them and suggesting directions for future investigation.

Liver volumetry and liver-regenerative interventions: history, rationale, and emerging tools

BACKGROUND

Postoperative hepatic insufficiency (PHI) is the most feared complication after hepatectomy. Volume of the future liver remnant (FLR) is one objectively measurable indicator to identify patients at risk of PHI. In this review, we summarized the development and rationale for the use of liver volumetry and liver-regenerative interventions and highlighted emerging tools that could yield new advancements in liver volumetry.

METHODS

A review of MEDLINE/PubMed, Embase, and Cochrane Library databases was conducted to identify literature related to liver volumetry. The references of relevant articles were reviewed to identify additional publications.

RESULTS

Liver volumetry based on radiologic imaging was developed in the 1980s to identify patients at risk of PHI and later used in the 1990s to evaluate grafts for living donor living transplantation. The field evolved in the 2000s by the introduction of standardized FLR based on the hepatic metabolic demands and in the 2010s by the introduction of the degree of hypertrophy and kinetic growth rate as measures of the FLR regenerative and functional capacity. Several liver-regenerative interventions, most notably portal vein embolization, are used to increase resectability and reduce the risk of PHI. In parallel with the increase in automation and machine assistance to physicians, many semi- and fully automated tools are being developed to facilitate liver volumetry.

CONCLUSION

Liver volumetry is the most reliable tool to detect patients at risk of PHI. Advances in imaging analysis technologies, newly developed functional measures, and liver-regenerative interventions have been improving our ability to perform safe hepatectomy.

Current Perspectives and Progress in Preoperative Portal Vein Embolization with Stem Cell Augmentation (PVESA)

Portal vein embolization with stem cell augmentation (PVESA) is an emerging approach for enhancing the growth of the liver segment that will remain after surgery (i.e., future liver remnant, FLR) in patients with liver cancer. Conventional portal vein embolization (PVE) aims to induce preoperative FLR growth, but it has a risk of failure in patients with underlying liver dysfunction and comorbid illnesses. PVESA combines PVE with stem cell therapy to potentially improve FLR size and function more effectively and efficiently. Various types of stem cells can help improve liver growth by secreting paracrine signals for hepatocyte growth or by transforming into hepatocytes. Mesenchymal stem cells (MSCs), unrestricted somatic stem cells, and small hepatocyte-like progenitor cells have been used to augment liver growth in preclinical animal models, while clinical studies have demonstrated the benefit of CD133 + bone marrow-derived MSCs and hematopoietic stem cells. These investigations have shown that PVESA is generally safe and enhances liver growth after PVE. However, optimizing the selection, collection, and application of stem cells remains crucial to maximize benefits and minimize risks. Additionally, advanced stem cell technologies, such as priming, genetic modification, and extracellular vesicle-based therapy, that could further enhance efficacy outcomes should be evaluated. Despite its potential, PVESA requires more investigations, particularly mechanistic studies that involve orthotopic animal models of liver cancer with concomitant liver injury as well as larger human trials.

Assessment of liver function by gadoxetic acid avidity in MRI in a model of rapid liver regeneration in rats

BACKGROUND

This animal study investigates the hypothesis of an immature liver growth following ALPPS (associating liver partition and portal vein ligation for staged hepatectomy) by measuring liver volume and function using gadoxetic acid avidity in magnetic resonance imaging (MRI) in models of ALPPS, major liver resection (LR) and portal vein ligation (PVL).

METHODS

Wistar rats were randomly allocated to ALPPS, LR or PVL. In contrast-enhanced MRI scans with gadoxetic acid (Primovist®), liver volume and function of the right median lobe (=future liver remnant, FLR) and the deportalized lobes (DPL) were assessed until post-operative day (POD) 5. Liver functionFLR/DPL was defined as the inverse value of time from injection of gadoxetic acid to the blood pool-corrected maximum signal intensityFLR/DPL multiplied by the volumeFLR/DPL.

RESULTS

In ALPPS (n = 6), LR (n = 6) and PVL (n = 6), volumeFLR and functionFLR increased proportionally, except on POD 1. Thereafter, functionFLR exceeded volumeFLR increase in LR and ALPPS, but not in PVL. Total liver function was significantly reduced after LR until POD 3, but never undercuts 60% of its pre-operative value following ALPPS and PVL.

DISCUSSION

This study shows for the first time that functional increase is proportional to volume increase in ALPPS using gadoxetic acid avidity in MRI.

Surgical management, including the role of transplantation, for intrahepatic and peri-hilar cholangiocarcinoma

Intrahepatic and peri-hilar cholangiocarcinoma are life threatening disease with poor outcomes despite optimal treatment currently available (5-year overall survival following resection 20-35%, and <10% cured at 10-years post resection). The insidious onset makes diagnosis difficult, the majority do not have a resection option and the high recurrence rate post-resection suggests that occult metastatic disease is frequently present. Advances in perioperative management, such as ipsilateral portal vein (and hepatic vein) embolisation methods to increase the future liver remnant volume, genomic profiling, and (neo)adjuvant therapies demonstrate great potential in improving outcomes. However multiple areas of controversy exist. Surgical resection rate and outcomes vary between centres with no global consensus on how 'resectable' disease is defined - molecular profiling and genomic analysis could potentially identify patients unlikely to benefit from resection or likely to benefit from targeted therapies. FDG-PET scanning has also improved the ability to detect metastatic disease preoperatively and avoid futile resection. However tumours frequently invade major vasculo-biliary structures, with resection and reconstruction associated with significant morbidity and mortality even in specialist centres. Liver transplantation has been investigated for very selected patients for the last decade and yet the selection algorithm, surgical approach and both value of both neoadjuvant and adjuvant therapies remain to be clarified. In this review, we discuss the contemporary management of intrahepatic and peri-hilar cholangiocarcinoma.

Extended Ligation of the Hepatic Vein May Yield a Similar Effect to Liver Venous Deprivation in a Rat Model

AIMS

To validate the hypothesis that hepatic vein ligation (HVL) alone may produce similar results to liver venous deprivation (LVD or HVL + portal vein ligation [PVL]).

METHODS

Rats were assigned to five groups, namely, the control group; the R group in which the right median hepatic vein (RMHV) was ligated; the M group in which the middle median hepatic vein (MMHV) was ligated; the RM group in which both the RMHV and MMHV were ligated (R + MMHVL, extended ligation of the hepatic veins); and the LVD group in which both the right median portal vein and the RMHV were ligated. The liver hypertrophy effect and liver enzymes were determined. Methylene blue staining and retrograde pressurized perfusion assays were performed to investigate the hemodynamic changes.

RESULTS

The RM and LVD groups exhibited similar significant hypertrophy in the future liver remnants when compared to that of the control group, and almost no additional hypertrophy effect was observed in the R and M groups. There was a remarkable elevation in serum transaminase levels in both groups. The methylene blue staining experiment indicated that pressure-dependent collaterals formed between the contiguous drainage areas, and the R + MMHVL procedure blocked the outflow of the right median lobe.

CONCLUSION

Extended ligation of the hepatic vein (R + MMHVL) resulted in a similar hypertrophy effect and hepatic damage to those of LVD (HVL + PVL) treatment in a rat model, and intrahepatic venovenous collaterals play key roles.

Tc-99m mebrofenin hepatobiliary scintigraphy to assess future liver remnant function before major liver surgery

BACKGROUND AND OBJECTIVES

Assessment of liver function is paramount before hepatectomy. This study aimed to assess future liver remnant function (FLR-F) using hepatobiliary scintigraphy (HBS) and to compare it to FLR volume (FLR-V) in the prediction of posthepatectomy liver failure (PHLF). The impact of volume and function gains were also assessed in patients undergoing portal vein embolization (PVE) or liver venous deprivation (LVD).

METHODS

All consecutive patients undergoing major hepatectomy between 02/2018 and 09/2021 with preoperative HBS were included. FLR-V was expressed as percentage of total liver volume and analyzed using preoperative computed tomography. FLR-V and FLR-F gains after embolization were expressed in percentage. Receiver operating characteristic analysis was performed to compare both methods in predicting PHLF.

RESULTS

Thirty-six patients were included. PVE and LVD were performed in 4 (11%) and 28 patients (78%), respectively. Overall, PHLF occurred in eight patients (22%). FLR-F gain after embolization showed significant ability to predict PHLF (area under the curve [AUC] = 0.789), with cut-off value of 150% showing a sensitivity of 1.00, a specificity of 0.42, and a negative predictive value of 1.00.

CONCLUSION

Preoperative HBS shows a high sensitivity to predict PHLF when HBS is performed twice to measure the function gain after venous embolization.

Liver Venous Deprivation for Rapid Liver Hypertrophy Before Major Hepatectomy: A Case Report

Liver venous deprivation (LVD) is an emerging, minimally invasive strategy to induce rapid liver hypertrophy of the future liver remnant (FLR) before a major hepatectomy. LVD (aka "double vein embolization") entails same-session percutaneous embolization of the portal and hepatic veins of the planned liver resection. This report discusses LVD's utilization and technical challenges in managing a 49-year-old male with recurrent multifocal colorectal liver metastases (CRLM). The patient initially underwent neoadjuvant FOLFOX chemotherapy followed by a simultaneous laparoscopic sigmoid colectomy and liver surgery (microwave ablation of segment V and wedge resections of segment one and IVb), followed by completion of chemotherapy. The patient had an R0 resection with clear colon and liver surgical margins. Nine months after the initial surgery, the patient had a rise in tumor markers, and surveillance imaging demonstrated recurrence of liver metastases in segments I and V. LVD was performed by interventional radiology, which led to a 28% increase in FLR (segments II, III, and IV); initially measuring 464 cm3 before LVD and measuring 594 cm3 on post-procedure day 21. The patient underwent right hemi-hepatectomy and caudate resection on post-procedure day 29. The patient did not have any complications and was discharged on postoperative day 6. The patient remains disease-free with no evidence of recurrence at 12 months follow-up.

Vascular Interventions in Oncology

Vascular interventions are an important and established tool in the management of the oncology patient. The goal of these procedures may be curative, palliative or adjunctive in nature. Some of the common vascular interventions used in oncology include transarterial embolisation or chemoembolisation, selective internal radiation therapy, chemosaturation, venous access lines, superior vena cava stenting and portal vein embolisation. We provide an overview of the principles, technology and approach of vascular techniques for tumour therapy in both the arterial and venous systems. Arterial interventions are currently mainly used in the management of hepatocellular carcinoma. Transarterial embolisation, chemoembolisation and selective internal radiation therapy deliver targeted catheter-delivered treatments with the aim of reducing tumour burden, controlling tumour growth or increasing survival in patients not eligible for transplantation. Chemosaturation is a regional chemotherapy technique that delivers high doses of chemotherapy directly to the liver via the hepatic artery, while reducing the risks of systemic effects. Venous interventions are more adjunctive in nature. Venous access lines are used to provide a means of delivering chemotherapy and other medications directly into the bloodstream. Superior vena cava stenting is a palliative procedure that is used to relieve symptoms of superior vena cava obstruction. Portal vein embolisation is a procedure that allows hypertrophy of a healthy portion of the liver in preparation for liver resection. Interventional radiology-led vascular interventions play an essential part of cancer management. These procedures are minimally invasive and provide a safe and effective adjunct to traditional cancer treatment methods. Appropriate work-up and discussion of each patient-specific problem in a multidisciplinary setting with interventional radiology is essential to provide optimum patient-centred care.

Sequential Y90 liver radioembolization and portal vein embolization: an additional strategy to downstage liver tumors and to enhance liver hypertrophy before major hepatectomies

BACKGROUND

Yttrium (Y)90 liver radioembolization (TARE) induces both tumor downsizing and contralateral liver hypertrophy. In this study, we report the preliminary results of a sequential strategy combining Y90 radioembolization and portal vein embolization (PVE) before major right liver resections.

METHODS

We retrospectively reviewed clinical, radiological, and biological data of 5 consecutive patients undergoing Y90 TARE-PVE before major right liver resections. Comparison was made with patients undergoing PVE alone or liver venous deprivation (LVD) during the same period.

RESULTS

Between January 2019 and September 2022, five patients underwent sequential TARE-PVE. Type of resection included the following: right hepatectomy (n = 1), right hepatectomy + 1 (n = 2), and right hepatectomy + 1 + 4 (n = 2) with no postoperative mortality. Volumetric data showed a mean hypertrophy ratio of 30.4% after TARE and an additional 37.4% after sequential PVE. Patients undergoing sequential TARE-PVE had higher hypertrophy ratio (p = 0.02; p = 0.004), hypertrophy degree (p = 0.02; p < 0.0001), shorter time to normalize bilirubin (p = 0.04), and prothrombin time (p = 0.003; p < 0.0001) compared with patients receiving LVD or PVE. Time from diagnosis to surgery was statistically significant longer in patients undergoing sequential TARE-PVE compared with LVD or PVE (293.4 ± 169.1 vs 54.18 ±18.26 vs 58.62±13.15; p = 0.0008; p = <0.0001).

CONCLUSIONS

This preliminary report suggests that sequential PVE and TARE can represent a safe and an alternative strategy to downstage liver tumors and to enhance liver hypertrophy before major hepatectomies. When compared with PVE and LVD, sequential TARE/PVE takes longer times but achieves some advantages which warrant further evaluation in a larger setting.

Establishment of a Rat Model of Liver Venous Deprivation: Simultaneous Portal and Hepatic Vein Ligation

BACKGROUND AND AIMS

The aim was to establish a liver venous deprivation (LVD) model in rats, compare hepatic hypertrophy between LVD and associated liver partition and portal vein ligation for staged hepatectomy (ALPPS), and explore the underlying mechanisms.

METHODS

The LVD or extended-LVD (e-LVD) group received portal vein ligation (PVL) combined with hepatic vein ligation (HVL). The ALPPS or e-ALPPS group received PVL plus parenchyma ligation. Liver regeneration was assessed by measuring the liver weight and performing pathological analysis. Liver functions and the sphingosine kinase 1 (SPHK1)/sphingosine-1-phosphate (S1P)/sphingosine-1-phosphate receptor 1 (S1PR1) pathway were also investigated.

RESULTS

All future liver remnants (FLRs) in the ALPPS, e-ALPPS, LVD, and e-LVD groups exhibited significant hypertrophy compared with the control group. The LVD and e-LVD procedures induced similar liver hypertrophy than that in the corresponding ALPPS groups. Furthermore, the LVD and e-LVD methods led to obvious cytolysis in the venous-deprived lobes as well as a noticeable increase in serum transaminase levels, while no necrosis was observed in the ALPPS and e-ALPPS groups. SPHK1/S1P/S1PR1 pathway were distinctly activated after operation, especially in congestive/ischemic livers.

CONCLUSIONS

We describe the first rat model of LVD and e-LVD with simultaneously associated HVL and PVL. Compared with the ALPPS technique, the LVD or e-LVD procedure had a comparable overall effect on the hypertrophy response and a stronger effect on liver function. The SPHK1/S1P/S1PR1 pathway was involved in the LVD- or ALPPS-induced liver remodeling.

Liver Venous Deprivation Versus Portal Vein Embolization Before Major Hepatectomy for Colorectal Liver Metastases: A Retrospective Comparison of Short- and Medium-Term Outcomes

BACKGROUND

Liver venous deprivation (LVD) is a recent radiological technique performed to induce hypertrophy of the future liver remnant. Medium-term results of major hepatectomy after LVD have never been compared with the actual standard of care, portal vein embolization (PVE).

METHODS

We retrospectively compared data from 33 consecutive patients who had undergone LVD (n = 17) or PVE (n = 16) prior to a right hemi-hepatectomy or right extended hepatectomy indicated for colorectal liver metastases (CRLM) between May 2015 and December 2019.

RESULTS

The 1-year and 3-year overall survival (OS) rates in the LVD group were 81.3% (95% confidence interval [CI]: 72-90) and 54.7% (95% CI: 46-63), respectively, against 85% (95% CI: 69-101) and 77.4% (95% CI: 54-100) in the PVE group; the differences were not statistically significant (p = 0.64). The median disease-free survival (DFS) rate was also comparable: 6 months (95% CI: 4-7) in the LVD group and 12 months (95% CI: 1.5-13) in the PVE group (p = 0.29). The overall intra-operative and post-operative complication rates were similar between the two groups. The mean daily kinetic growth rate (KGR) was found to be higher after LVD than after PVE (0.2% vs. 0.1%, p = 0.05; 10 cc/day vs. 4.8 cc/day, p = 0.03), as was the mean increase in future liver remnant volume (FLR-V) (49% vs. 27%, p = 0.01).

CONCLUSIONS

The LVD technique is well tolerated in patients undergoing right hemi-hepatectomy or right extended hepatectomy for CRLM. When compared with the PVE technique, the LVD technique has similar peri-operative and medium-term outcomes, but higher KGR and FLR-V increase.

Portal Vein Embolization: Rationale, Techniques, and Outcomes to Maximize Remnant Liver Hypertrophy with a Focus on Contemporary Strategies

Hepatectomy remains the gold standard for curative therapy for patients with limited primary or metastatic hepatic tumors as it offers the best survival rates. In recent years, the indication for partial hepatectomy has evolved away from what will be removed from the patient to the volume and function of the future liver remnant (FLR), i.e., what will remain. With this regard, liver regeneration strategies have become paramount in transforming patients who previously had poor prognoses into ones who, after major hepatic resection with negative margins, have had their risk of post-hepatectomy liver failure minimized. Preoperative portal vein embolization (PVE) via the purposeful occlusion of select portal vein branches to promote contralateral hepatic lobar hypertrophy has become the accepted standard for liver regeneration. Advances in embolic materials, selection of treatment approaches, and PVE with hepatic venous deprivation or concurrent transcatheter arterial embolization/radioembolization are all active areas of research. To date, the optimal combination of embolic material to maximize FLR growth is not yet known. Knowledge of hepatic segmentation and portal venous anatomy is essential before performing PVE. In addition, the indications for PVE, the methods for assessing hepatic lobar hypertrophy, and the possible complications of PVE need to be fully understood before undertaking the procedure. The goal of this article is to discuss the rationale, indications, techniques, and outcomes of PVE before major hepatectomy.

A prospective study of sequential hepatic vein embolization after portal vein embolization in patients scheduled for right-sided major hepatectomy: Results of feasibility and surgical strategy using functional liver assessment

BACKGROUND

Hepatic vein embolization (HVE) added to portal vein embolization (PVE) can further increase future remnant liver volume (FRLV) compared with PVE alone. This study was aimed to evaluate feasibility of sequential HVE in a prospective trial and to verify surgical strategy using functional FRLV (fFRLV).

METHODS

Hepatic vein embolization was prospectively indicated for post-PVE patients scheduled for right-sided major hepatectomy if the resection limit of fFRLV using EOB-magnetic resonance imaging was not satisfied. The resection limit was fFRLV: 615 mL/m² for predicting post-hepatectomy liver failure. Patients who underwent sequential PVE-HVE (n = 12) were compared with those who underwent PVE alone (n = 31).

RESULTS

All patients underwent HVE with no severe complications. Median fFRLV increased from 396 (range: 251-581) to 634 (range: 422-740) mL/m² by sequential PVE-HVE. From PVE to HVE, both of FRLV (P < .001) and fFRLV (P = .005) significantly increased. The increased width of fFRLV was larger than that of FRLV after performing HVE. Median growth rate was 71.3 (range: 33.3-80.3) %, which was higher than that of PVE alone (27.0%, range: 6.0-78.0). All-cohort resection rate was 88.3%. Strategy of using fFRLV for the resection limit and performing HVE in patients with insufficient functional volume resulted in no liver failure in all patients who underwent hepatectomy.

CONCLUSIONS

Sequential HVE after PVE is feasible and safe, and HVE induced possibility of further liver growth and its functional improvement. Our surgical strategy using fFRLV may be justified.

Portal vein embolization failure: Current strategies and future perspectives to improve liver hypertrophy before major oncological liver resection

Portal vein embolization (PVE) is currently considered the standard of care to improve the volume of an inadequate future remnant liver (FRL) and decrease the risk of post-hepatectomy liver failure (PHLF). PHLF remains a significant limitation in performing major liver surgery and is the main cause of mortality after resection. The degree of hypertrophy obtained after PVE is variable and depends on multiple factors. Up to 20% of patients fail to undergo the planned surgery because of either an inadequate FRL growth or tumor progression after the PVE procedure (usually 6-8 wk are needed before surgery). The management of PVE failure is still debated, with a lack of consensus regarding the best clinical strategy. Different additional techniques have been proposed, such as sequential transarterial chemoembolization followed by PVE, segment 4 PVE, intra-portal administration of stem cells, dietary supplementation, and hepatic vein embolization. The aim of this review is to summarize the up-to-date strategies to overcome such difficult situations and discuss future perspectives on improving FRL hypertrophy.

Novel liver vein deprivation technique that promotes increased residual liver volume (with video): A case report

BACKGROUND

Inadequate volume of future liver remnant (FLR) is a major challenge for hepatobiliary surgeons treating large or multiple liver tumors. As an alternative to associating liver partition and portal vein ligation (ALPPS) for staged hepatectomy and liver venous deprivation (LVD) using stage 1 interventional radiology for vascular embolization combined with stage 2 open liver resection have been used.

CASE SUMMARY

A novel modified LVD technique was performed in a patient with pancreatic neuroendocrine tumor with liver metastases by using stage 1 laparoscopic ligation of the right hepatic vein, right posterior portal vein, and short hepatic veins combined with local excision of three liver metastases in the left hemiliver. The operation was followed three days later by interventional radiology to embolize an anomalous right anterior portal vein to complete LVD. A stage 2 laparoscopic right hemihepatectomy and pancreaticosplenectomy were then carried out.

CONCLUSION

The minimally invasive technique promoted a rapid increase, comparable to ALPPS, in volume of the FLR after the stage 1 operation to allow the laparoscopic stage 2 resection to be performed.

Promoting Surgical Resection through Future Liver Remnant Hypertrophy

An inadequate future liver remnant (FLR) can preclude curative-intent surgical resection for patients with primary or secondary hepatic malignancies. For patients with normal baseline liver function and without risk factors, an FLR of 20% is needed to maintain postsurgical hepatic function. However, the FLR requirement is higher for patients who are exposed to systemic chemotherapy (FLR, >30%) or have cirrhosis (FLR, >40%). Interventional radiologic and surgical methods to achieve FLR hypertrophy are evolving, including portal vein ligation, portal vein embolization, radiation lobectomy, hepatic venous deprivation, and associating liver partition and portal vein ligation for staged hepatectomy. Each technique offers particular advantages and disadvantages. Knowledge of these procedures can help clinicians to choose the suitable technique for each patient. The authors review the techniques used to develop FLR hypertrophy, focusing on technical considerations, outcomes, and the advantages and disadvantages of each approach. Online supplemental material is available for this article. ^©RSNA, 2022.

Current trends in regenerative liver surgery: Novel clinical strategies and experimental approaches

Liver resections are performed to cure patients with hepatobiliary malignancies and metastases to the liver. However, only a small proportion of patients is resectable, largely because only up to 70% of liver tissue is expendable in a resection. If larger resections are performed, there is a risk of post-hepatectomy liver failure. Regenerative liver surgery addresses this limitation by increasing the future liver remnant to an appropriate size before resection. Since the 1980s, this surgery has evolved from portal vein embolization (PVE) to a multiplicity of methods. This review presents an overview of the available methods and their advantages and disadvantages. The first use of PVE was in patients with large hepatocellular carcinomas. The increase in liver volume induced by PVE equals that of portal vein ligation, but both result only in a moderate volume increase. While awaiting sufficient liver growth, 20%–40% of patients fail to achieve resection, mostly due to the progression of disease. The MD Anderson Cancer Centre group improved the PVE methodology by adding segment 4 embolization (“high-quality PVE”) and demonstrated that oncological results were better than non-surgical approaches in this previously unresectable patient population. In 2012, a novel method of liver regeneration was proposed and called Associating Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS). ALPPS accelerated liver regeneration by a factor of 2–3 and increased the resection rate to 95%–100%. However, ALPPS fell short of expectations due to a high mortality rate and a limited utility only in highly selected patients. Accelerated liver regeneration, however, was there to stay. This is evident in the multiplicity of ALPPS modifications like radiofrequency or partial ALPPS. Overall, rapid liver regeneration allowed an expansion of resectability with increased perioperative risk. But, a standardized low-risk approach to rapid hypertrophy has been missing and the techniques used and in use depend on local expertise and preference. Recently, however, simultaneous portal and hepatic vein embolization (PVE/HVE) appears to offer both rapid hypertrophy and no increased clinical risk. While prospective randomized comparisons are underway, PVE/HVE has the potential to become the future gold standard.

Dragon 1 Protocol Manuscript: Training, Accreditation, Implementation and Safety Evaluation of Portal and Hepatic Vein Embolization (PVE/HVE) to Accelerate Future Liver Remnant (FLR) Hypertrophy

STUDY PURPOSE

The DRAGON 1 trial aims to assess training, implementation, safety and feasibility of combined portal- and hepatic-vein embolization (PVE/HVE) to accelerate future liver remnant (FLR) hypertrophy in patients with borderline resectable colorectal cancer liver metastases.

METHODS

The DRAGON 1 trial is a worldwide multicenter prospective single arm trial. The primary endpoint is a composite of the safety of PVE/HVE, 90-day mortality, and one year accrual monitoring of each participating center. Secondary endpoints include: feasibility of resection, the used PVE and HVE techniques, FLR-hypertrophy, liver function (subset of centers), overall survival, and disease-free survival. All complications after the PVE/HVE procedure are documented. Liver volumes will be measured at week 1 and if applicable at week 3 and 6 after PVE/HVE and follow-up visits will be held at 1, 3, 6, and 12 months after the resection.

RESULTS

Not applicable.

CONCLUSION

DRAGON 1 is a prospective trial to assess the safety and feasibility of PVE/HVE. Participating study centers will be trained, and procedures standardized using Work Instructions (WI) to prepare for the DRAGON 2 randomized controlled trial. Outcomes should reveal the accrual potential of centers, safety profile of combined PVE/HVE and the effect of FLR-hypertrophy induction by PVE/HVE in patients with CRLM and a small FLR.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT04272931 (February 17, 2020). Toestingonline.nl: NL71535.068.19 (September 20, 2019).

Summary of key guidelines for locoregional treatment of HCC in Asia, Europe, South and North America

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide accounting for over 800,000 new cases in 2018, with the highest incidence in Asia and Africa where hepatitis B is the most common risk factor. In Europe, Japan, and the United States, hepatitis C chronic alcohol abuse and non-alcoholic fatty liver disease are more common risk factors. Five-year survival is low, less than 20% worldwide. HCC is a particularly challenging disease to treat because therapeutic options and prognosis must also consider hepatitis or cirrhosis independent of the malignancy. Locoregional therapies (LRT) including ablation, arterially directed therapy and external beam radiation are the preferred treatments for patients with good performance status, unresectable disease limited to the liver and preserved liver function. In practice, patients with portal vein tumor thrombus and limited extrahepatic disease may also be considered candidates for LRT. There are several guidelines developed by expert panels provide recommendations on treating this challenging disease including the Barcelona Clinic Liver Cancer, European Association for the Study of the Liver, European Society for Medical Oncology, American Association for the Study of the Liver Diseases, and the National Comprehensive Cancer Network. The purpose of this paper is to review the guidelines as they are applied clinically in regions with high incidence of HCC.

Liver venous deprivation versus associating liver partition and portal vein ligation for staged hepatectomy for colo-rectal liver metastases: a comparison of early and late kinetic growth rates, and perioperative and oncological outcomes

BACKGROUND

Different techniques have been developed to optimize the Future Liver Remnant (FLR). Associated liver partition and portal vein ligation for staged hepatectomy (ALPPS) and liver venous deprivation (LVD) have shown the higher hypertrophy rates, but their place in clinical practice is still debated.

METHODS

Thirty-two consecutive ALPPS and LVD procedures for CRLM performed between December 2015 and December 2019 were included. This retrospective study evaluated kinetic growth rates (KGR) as primary outcome, and perioperative and oncological outcomes as secondary endpoints.

RESULTS

A total of 17 patients underwent LVD before surgery, whereas 15 underwent ALPPS. On early evaluation (7 vs 9 days, respectively), KGR did not differ between ALPPS and LVD cohort (0.8% per day vs 0.3% per day, p = 0.70; 23 cc/day vs 26 cc/day, p = 0.31). Late evaluation (21 vs 9 days) showed a KGR significantly decreased in the LVD group (0.6% per day vs 0.2% per day, p = 0.21; 20 cc/day vs 10 cc/day p = 0.02). Mean FLR-V increase was comparable in the two groups (60% vs 49%, p 0.32). Successful resection rate was 100% and 94% in LVD and ALPPS group, respectively. The hospital stay (p < 0.0001) and severe complications rate (p = 0.05) were lower after LVD. One and 3-years overall survival (OS) were 72,7% and 27,4% in the ALPSS group, versus 81,3% and 54,7% in LVD group (p = 0.10). The Median DFS was comparable between both techniques (6.1 months and 5.9 respectively, p = 0.66).

CONCLUSIONS

LVD and ALPPS shows similar KGR during the early period following preparation as well as similar survival outcomes. Hospital stay and severe complications are lower after LVD.

Liver Venous Deprivation (LVD) Versus Portal Vein Embolization (PVE) Alone Prior to Extended Hepatectomy: A Matched Pair Analysis

BACKGROUND

To investigate whether liver venous deprivation (LVD) as simultaneous, portal vein (PVE) and right hepatic vein embolization offers advantages in terms of hypertrophy induction before extended hepatectomy in non-cirrhotic liver.

MATERIALS AND METHODS

Between June 2018 and August 2019, 20 patients were recruited for a prospective, non-randomized study to investigate the efficacy of LVD. After screening of 134 patients treated using PVE alone from January 2015 to August 2019, 14 directly matched pairs regarding tumor entity (cholangiocarcinoma, CC and colorectal carcinoma, CRC) and hypertrophy time (defined as time from embolization to follow-up imaging) were identified. In both treatment groups, the same experienced reader (> 5 years experience) performed imaging-based measurement of the volumes of liver segments of the future liver remnant (FLR) prior to embolization and after the standard clinical hypertrophy interval (~ 30 days), before surgery. Percentage growth of segments was calculated and compared.

RESULTS

After matched follow-up periods (mean of 30.5 days), there were no statistically significant differences in relative hypertrophy of FLRs. Mean ± standard deviation relative hypertrophy rates for LVD/PVE were 59 ± 29.6%/54.1 ± 27.6% (p = 0.637) for segments II + III and 48.2 ± 22.2%/44.9 ± 28.9% (p = 0.719) for segments II-IV, respectively.

CONCLUSIONS

LVD had no significant advantages over the standard method (PVE alone) in terms of hypertrophy induction of the FLR before extended hepatectomy in this study population.

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.

Future remnant Liver optimization: preoperative assessment, volume augmentation procedures and management of PVE failure

Surgery is the cornerstone treatment for patients with primary or metastatic hepatic tumors. Thanks to surgical and anesthetic technological advances, current indications for liver resections have been significantly expanded to include any patient in whom all disease can be resected with a negative margin (R0) while preserving an adequate future residual liver (FRL). Post-hepatectomy liver failure (PHLF) is still a feared complication following major liver surgery, associated with high morbidity, mortality and cost implications. PHLF is mainly linked to both the size and quality of the FRL. Significant advances have been made in detailed preoperative assessment, to predict and mitigate this complication, even if an ideal methodology has yet to be defined. Several procedures have been described to induce hypertrophy of the FRL when needed. Each technique has its advantages and limitations, and among them portal vein embolization (PVE) is still considered the standard of care. About 20% of patients after PVE fail to undergo the scheduled hepatectomy, and newer secondary procedures, such as segment 4 embolization, ALPPS and HVE, have been proposed as salvage strategies. The aim of this review is to discuss the current modalities available and new perspectives in the optimization of FRL in patients undergoing major liver resection.

Percutaneous liver venous deprivation: outcomes in heavily pretreated metastatic colorectal cancer patients

BACKGROUND

To evaluate liver venous deprivation (LVD) outcomes in patients with colorectal liver metastasis (CRLM) heavily pretreated with systemic and hepatic arterial infusion pump (HAIP) chemotherapies that had an anticipated insufficient future liver remnant (FLR) hypertrophy after portal vein embolization (PVE).

METHODS

PVE was performed with liquid embolics using a transsplenic or ipsilateral transhepatic approach. Simultaneously and via a trans-jugular approach, the right hepatic vein was embolized with vascular plugs. Liver volumetry was assessed on computed tomography before and 3-6 weeks after LVD.

RESULTS

Twelve consecutive CRLM patients that underwent LVD before right hepatectomy or trisectionectomy were included, all previously treated with systemic chemotherapy for a mean of 11.9 months. Six patients had additional HAIP. After embolization, FLR ratio increased from 28.7% ± 5.9 to 42.2% ± 9.0 (P < 0.01). Mean kinetic growth rate (KGR) was 3.56%/week ± 2.3, with a degree of hypertrophy (DH) of 13.8% ± 7.1. In the HAIP subgroup, mean KGR and DH were respectively 3.58%/week ± 2.8 and 14.3% ± 8.7. No severe complications occurred. Ten patients reached surgery after 39 days ± 7.5.

CONCLUSION

In heavily pretreated patients, LVD safely stimulated a rapid and effective FLR hypertrophy, with a resultant high rate of resection.

Liver venous deprivation for resection of advanced hilar cholangiocarcinoma—a case report and review of the literature

Hilar cholangiocarcinoma is a rare primary malignancy associated with a dismal prognosis. Currently, complete extended right or left-sided hepatectomy is the primary curative therapy. Achieving a negative resection margin is associated with long-term survival and better quality of life, while post-hepatectomy liver failure (PHLF) due to insufficient liver remnant remains the most dreaded complication with a negative effect on overall survival. Precise preoperative management with sufficient future remnant liver (FRL) volume is the key to achieving good results in the treatment of bile duct carcinoma. To present a case report and a literature review for preoperative FRL optimization prior to major hepatectomies for hilar cholangiocarcinoma. Improvement of postoperative outcomes after extended liver resections in the case of hilar cholangiocarcinoma. A 62-year-old Caucasian woman with Lynch syndrome presented to our department with a hilar cholangiocarcinoma Bismuth type IIIa. The patient had an insufficient future liver volume for extended liver resection. She underwent preoperative preconditioning using a liver venous deprivation (LVD) and underwent two weeks later a right trisectorectomy without any interventional complications. Liver function remained stable postoperatively. The patient was discharged on the 20th postoperative day without major surgical post-operative complications or the need for readmission. LVD is a technically feasible, safe, and effective procedure to increase the FRL in a short period of time with low intra and post-operative complications and therefore improving the survival of patients with hilar cholangiocarcinoma.

Portal Vein Embolization Using N-Butyl Cyanoacrylate-Glue: What Impact Does a Central Vascular Plug Have?

Purpose

To examine if the addition of a central vascular plug (CVP) to portal vein embolization (PVE) with N-butyl cyanoacrylate-glue (NBCA) increases future liver remnant (FLR) growth.

Material and Methods

This is a single-center retrospective study of 115 consecutive patients with colorectal liver metastases undergoing PVE in 2013–2019. All patients were embolized with NBCA as the main embolic agent. In 2017–2019 NBCA was combined with a CVP in the central part of the right portal vein. Growth of the FLR and standardized FLR (sFLR) including degree of hypertrophy (DH) and kinetic growth rate (KGR) were analyzed, as well as procedure data such as use of cone-beam CT (CBCT), dose area product (DAP), fluoroscopy time and contrast dose.

Results

A total of 40 patients (35%) underwent PVE with a combination of CVP and NBCA. The DH was higher in these patients after 4 weeks, mean 13.6% (SD 7.8) vs. 10.5% (SD 6.4; p = 0.022), verified in multivariate analysis (coefficient 4.1, p = 0.015). A CVP did not significantly increase the resection rate (90% vs 82%, p = 0.4). Cone beam CT was used in 65 patients (57%). Use of CBCT did not affect FLR growth, and fluoroscopy time and contrast doses were not different in patients having a CBCT or not. Slightly lower DAP (median 3375 vs. 4499 cGy*cm²; p = 0.09) was seen in procedures where CBCT was used.

Conclusion

A CVP in addition to NBCA embolization was associated with increased growth of the FLR compared to NBCA alone.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00270-021-03014-w.

Induction of Robust Future Liver Remnant Hypertrophy Before Hepatectomy With a Modified Liver Venous Deprivation Technique Using a Trans-venous Access for Hepatic Vein Embolization

Purpose: Hepatic and/or portal vein embolization are performed before hepatectomy for patients with insufficient future liver remnant and usually achieved with a trans-hepatic approach. The aim of the present study is to describe a modified trans-venous liver venous deprivation technique (mLVD), avoiding the potential risks and limitations of a percutaneous approach to hepatic vein embolization, and to assess the safety, efficacy, and surgical outcome after mLVD. Materials and Methods: Retrospective single-center institutional review board-approved study. From March 2016 to June 2019, consecutive oncologic patients with combined portal and hepatic vein embolization were included. CT volumetric analysis was performed before and after mLVD to assess liver hypertrophy. Complications related to mLVD and surgical outcome were obtained from medical records. Results: Thirty patients (62.7 ± 14.5 years old, 20 men) with liver metastasis (60%) or primary liver cancer (40%) underwent mLVD. Twenty-one patients (70%) had hepatic vein anatomic variants. Technical success of mLVD was 100%. Four patients had complications (three minor and one major). FLR hypertrophy was 64.2% ± 51.3% (mean ± SD). Twenty-four patients (80%) underwent the planned hepatectomy and no surgery was canceled as a consequence of mLVD complications or insufficient hypertrophy. Fifty percent of patients (12/24) had no or mild complications after surgery (Clavien-Dindo 0-II), and 45.8% (11/24) had more serious complications (Clavien-Dindo III-IV). Thirty-day mortality was 4.2% (1/24). Conclusion: mLVD is an effective method to induce FLR hypertrophy. This technique is applicable in a wide range of oncologic situations and in patients with complex right liver vein anatomy.

Portal vein embolization: rationale, techniques, outcomes and novel strategies

The incidence of liver cancer has grown in the past decade, with 905,677 new cases and 830,180 deaths in 2020. According to the highest annual fatality ratio, liver cancer is the third-leading cause of cancer-related deaths worldwide. Surgical resection is the mainstay treatment for long-term survival. However, only 25% of patients are surgical candidates. Recent surgical concepts, techniques and multidisciplinary management were developed, including interventional radiology procedures that improve the management algorithm, expand the indications and limit dropouts from curative treatment. This review summarizes up-to-date information on interventional radiology in the management of liver tumors.

Hepatocellular Carcinoma in 2021: An Exhaustive Update

Primary liver cancer is a challenging global health concern with an estimated more than a million persons to be affected annually by the year 2025. The commonest type is hepatocellular carcinoma (HCC), which has been increasing in incidence the world over, mostly due to chronic viral hepatitis B infection. In the last decade, paradigm changes in the etiology, understanding of molecular biology, and pathogenesis, including the role of gut microbiota; medical and surgical treatments, and outcome trends are notable. The application of omics-based technology has helped us unlock the molecular and immune landscape of HCC, through which novel targets for drug treatment such as immune-checkpoint inhibitors have been identified. Novel tools for the surveillance and diagnosis of HCC include protein-, genomics-, and composite algorithm-based clinical/biomarker panels. Magnetic resonance imaging-based novel techniques have improved HCC diagnosis through ancillary features that enhance classical criteria while positron emission tomography has shown value in prognostication. Identification of the role of gut microbiota in the causation and progression of HCC has opened areas for novel therapeutic research. A select group of patients still benefit from modified surgical and early interventional radiology treatments. Improvements in radiotherapy protocols, identification of parameters of futility among radiological interventions, and the emergence of novel first-line systemic therapies that include a combination of antiangiogenic and immune-checkpoint inhibitors have seen a paradigm change in progression-free and overall survival. The current review is aimed at providing exhaustive updates on the etiology, molecular biology, biomarker diagnosis, imaging, and recommended treatment options in patients with HCC.

Vascular surgery in liver resection

Vascular surgery in liver resection is a standard part of liver transplantation, but is also used in oncological liver surgery. Malignant liver tumors with vascular involvement have a poor prognosis without resection. Surgery is currently the only treatment to provide long-term survival in advanced hepatic malignancy. Even though extended liver resections are increasingly performed, vascular involvement with need of vascular reconstruction is still considered a contraindication for surgery in many institutions. However, vascular resection and reconstruction in liver surgery-despite being complex procedures-are safely performed in specialized centers. The improvements of the postoperative results with reduced postoperative morbidity and mortality are a result of rising surgical and anesthesiological experience and advancements in multimodal treatment concepts with preconditioning measures regarding liver function and systemic treatment options. This review focuses on vascular surgery in oncological liver resections. Even though many surgical techniques were developed and are also used during liver transplantation, this special procedure is not particularly covered within this review article. We provide a summary of vascular reconstruction techniques in oncological liver surgery according to the literature and present also our own experience. We aim to outline the current advances and standards in extended surgical procedures for liver tumors with vascular involvement established in specialized centers, since curative resection improves long-term survival and shifts palliative concepts to curative therapy.

State-of-the-art surgery for hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the most commonly diagnosed primary liver tumor with an increasing incidence worldwide. Management of patients with HCC is largely dictated by the presence of cirrhosis, disease stage, underlying liver function, and patient performance status.

PURPOSE

We provide an update on key aspects of surgical treatment options for patients with HCC. RESULTS & CONCLUSIONS: Liver resection and transplantation remain cornerstone treatment options for patients with early-stage disease and constitute the only potentially curative options for HCC. Selection of patients for surgical treatment should include a thorough evaluation of tumor characteristics and biology, as well as evidence-based use of various available treatment options to achieve optimal long-term outcomes for patients with HCC.

Liver Venous Deprivation (LVD) or Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS)?: A Retrospective Multicentric Study

OBJECTIVE

To compare two techniques of remnant liver hypertrophy in candidates for extended hepatectomy: radiological simultaneous portal vein (PVE) and hepatic vein embolization (HVE); namely liver venous deprivation (LVD), and ALPPS.

SUMMARY BACKGROUND DATA

Recent advances in chemotherapy and surgical techniques have widened indications for extended hepatectomy, before which remnant liver augmentation is mandatory. ALPPS and LVD typically show higher hypertrophy rates than PVE, but their respective places in patient management remain unclear.

METHODS

All consecutive ALPPS and LVD procedures performed in eight French centers between 2011 and 2020 were included. The main endpoint was the successful resection rate (resection rate without 90-day mortality) analyzed according to an intention-to-treat principle. Secondary endpoints were hypertrophy rates, intra- and post-operative outcomes.

RESULTS

Among 209 patients, 124 had LVD 37 [13,1015] days before surgery, while 85 underwent ALPPS with an inter-stages period of 10 [6, 69] days. ALPPS was mostly-performed for colorectal liver metastases (CRLM), LVD for CRLM and perihilar cholangiocarcinoma. Hypertrophy was faster for ALPPS. Successful resection rates were 72.6% for LVD ± rescue ALPPS (n=6) versus 90.6% for ALPPS (p<0.001). Operative duration, blood losses and length-of-stay were lower for LVD, while 90-day major complications and mortality were comparable. Results were globally unchanged for CRLM patients, or after excluding the early 2 years of experience (learning-curve effect).

CONCLUSIONS

This study is the first one comparing LVD versus ALPPS in the largest cohort so far. Despite its retrospective design, it yields original results that may serve as the basis for a prospective study.

Combined simultaneous embolization of the portal vein and hepatic vein (double vein embolization) - a technical note about embolization sequence

Background

Simultaneous portal vein embolization (PVE) and hepatic vein embolization (HVE) has been shown to be feasible, safe and lead to a faster growth of future liver remnant (FLR) than PVE alone. The objective of this study is to highlight different technical aspects as well as importance of embolization order.

Materials and methods

Seven patients were treated with simultaneous PVE and HVE. In three cases, HVE was performed first followed by PVE and in four cases the other way around. Portal vein branches were embolized using Glubran-Lipiodol mixture in all cases. Hepatic veins were embolized using Amplatzer II plugs sized 8–20 mm. Specific consideration was given to depth of glue penetration in the portal vein defined by visible branch order on the treated side.

Results

Six of seven patients were discharged home the same day. One patient with infected tumor necrosis died of liver failure 40 days later, otherwise there were no periprocedural clinical complications. Median glue penetration was to the 5th order (4th – 5th) when PVE was performed first and 3rd order (2nd - 4th) when PVE was performed after HVE. In one PVE first case, glue spillage was seen due to marked reduced flow in the right portal vein. There was sufficient FLR growth for subsequent surgical resection in the remaining six patients.

Conclusion

PVE should be performed prior to HVE because the reduced flow in the portal vein after HVE leads to less deep glue penetration with presumably increased risk of contralateral spillage.

Ipsilateral access portal venous embolization (PVE) for preoperative hypertrophy exhibits low complication rates in Clavien-Dindo and CIRSE scales

Background

Portal venous embolization (PVE) is a minimal invasive preoperative strategy that aims to increase future liver remnant (FLR) in order to facilitate extended hemihepatectomy. We analyzed our data retrospectively regarding complications and degree of hypertrophy (DH).

Methods: 88 patients received PVE either by particles / coils (n = 77) or by glue / oil (n = 11), supported by 7 right hepatic vein embolizations (HVE) by coils or occluders. All complications were categorized by the Clavien- Dindo (CD) and the CIRSE classification.

Results

In 88 patients (median age 68 years) there was one intervention with a biliary leak and subsequent drainage (complication grade 3 CD, CIRSE 3), two with prolonged hospital stay (grade 2 CD, grade 3 CIRSE) and 13 complications grade 1 CD, but no complications of grade 4 or higher neither in Clavien- Dindo nor in CIRSE classification. The median relative increase in FLR was 47% (SD 35%). The mean pre-intervention standardized FLR rose from 23% (SD 10%) to a post-intervention standardized FLR of 32% (SD 12%). The degree of hypertrophy (DH) was 9,3% (SD 5,2%) and the kinetic growth rate (KGR) per week was 2,06 (SD 1,84).

Conclusion

PVE and, if necessary, additional sequential HVE were safe procedures with a low rate of complications and facilitated sufficient preoperative hypertrophy of the future liver remnant.

Ligation of the middle hepatic vein to increase hypertrophy induction during the ALPPS procedure

PURPOSE

Here, we analyse the technical modification of the ALPPS procedure, ligating the middle hepatic vein during the first step of the operation to enhance remnant liver hypertrophy.

METHODS

In 20 of 37 ALPPS procedures, the middle hepatic vein was ligated during the first step. Hypertrophy of the functional remnant liver volume was assessed in addition to postoperative courses.

RESULTS

Volumetric analysis showed a significant volume increase, especially for patients with colorectal metastases. Pre-existing liver parenchyma damage (odds ratio = 0.717, p = 0.017) and preoperative chemotherapy were found to be significant predictors (odds ratio = 0.803, p = 0.045) of higher morbidity and mortality. In addition, a survival benefit for maintenance of middle hepatic vein was shown.

CONCLUSION

This technical modification of the ALPPS procedure can accentuate future liver remnant volume hypertrophy. The higher morbidity and mortality observed are most likely associated with pre-existing parenchymal damage within this group.

99mTc-mebrofenin hepatobiliary scintigraphy and volume metrics before liver preparation: correlations and discrepancies in non-cirrhotic patients

Background

Accurate identification of insufficient future liver remnant (FLR) is required to select patients for liver preparation and limit the risk of post-hepatectomy liver failure (PHLF). The objective of this study was to investigate the correlations and discrepancies between the most-commonly used FLR volume metrics and ^99mTc-mebrofenin hepatobiliary scintigraphy (HBS).

Methods

In 101 non-cirrhotic patients who underwent HBS before major hepatectomy, we retrospectively analyzed the correlations and discrepancies between FLR function and FLR volume metrics: actual percentage (FLRV%), standardized to body surface area (FLRV%^BSA) and weight (FLRV%^weight), and FLR to body weight ratio (FLRV-BWR).

Results

Among 67 patients with FLR function ≥2.69%/min/m², PHLF was observed in none and 13 patients according to respectively 50-50 and ISGLS criteria. FLRV%, FLRV%^BSA, FLRV%^weight and FLRV-BWR significantly correlated with FLR function (P<0.001), with Spearman's correlation coefficients of 0.680, 0.704, 0.698, and 0.711, respectively. No difference was observed between the areas under the curve of FLRV%, FLRV%^BSA, FLRV%^weight and FLR-BWR (all P=ns). Overall, the percentages of patients misclassified by FLRV%, FLRV%^BSA, FLRV%^weight (thresholds: 30%) and FLR-BWR (threshold: 0.5) versus FLR function (threshold: 2.69%/min/m²) were 23.8% (95% CI: 15.9-33.3%), 18.8% (95% CI: 11.7-27.8%), 17.8% (95% CI: 11-26.7%), and 31.7% (95% CI: 22.8-41.7%), respectively. FLR volume metrics wrongly classified 1-13.9% of patients with sufficient FLR function (i.e., ≥2.69%/min/m²), and 9.9-30.7% of patients with insufficient FLR function. FLRV-BWR was the most and the least reliable measure to identify patients with sufficient and insufficient FLR function, respectively.

Conclusions

Despite significant correlations, the discrepancy rates between FLR volume and function metrics speaks in favor of implementing ^99mTc-mebrofenin HBS in the work-up before liver preparation.

Complex Liver Resections for Intrahepatic Cholangiocarcinoma

The only curative treatment option for intrahepatic cholangiocarcinoma (iCCA) is liver resection. Due to central tumor localization and vascular invasion, complex liver resections play an important role in curative treatment. However, the long-term outcomes after complex liver resection are not known. Methods: A retrospective cohort study was conducted for all patients undergoing liver surgery for iCCA. Complex liver resections included ante situm resections, associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) and major liver resection with vascular reconstructions. Results: Forty-nine patients (34%) received complex liver resection, 66 patients (46%) received conventional liver resection and 28 patients (20%) were not resectable during exploration. Preoperative characteristics were not different between the groups, except for Union for International Cancer Control (UICC) stages. The postoperative course for complex liver resections was associated with more complications and perioperative mortality. However, long-term survival was not different between complex and conventional resections. Independent risk factors for survival were R0 resections and UICC stage. Four patients underwent ante situm resection without any mortality. Conclusions: Complex liver resections are justified in selected patients and survival is comparable with conventional liver resections. Survival in iCCA is affected by UICC stage or resections margins and not by the complexity of the case.

BestFLR Trial: Liver Regeneration at CT before Major Hepatectomies for Liver Cancer-A Randomized Controlled Trial Comparing Portal Vein Embolization with N-Butyl-Cyanoacrylate Plus Iodized Oil versus Polyvinyl Alcohol Particles Plus Coils

Background In patients with liver cancer, portal vein embolization (PVE) is recommended to promote liver growth before major hepatectomies. However, the optimal embolization strategy has not been established. Purpose To compare liver regeneration as seen at CT in participants with liver cancer, before major hepatectomies, with N-butyl-cyanoacrylate (NBCA) plus iodized oil versus standard polyvinyl alcohol (PVA) particles plus coils, for PVE. Materials and Methods In this single-center, prospective, randomized controlled trial (Best Future Liver Remnant, or BestFLR, trial; International Standard Randomized Controlled Trial Number 16062796), PVE with NBCA plus iodized oil was compared with standard PVE with PVA particles plus coils in participants with liver cancer. Participant recruitment started in November 2017 and ended in March 2020. Participants were randomly assigned to undergo PVE with PVA particles plus coils or PVE with NBCA plus iodized oil. The primary end point was liver growth assessed with CT 14 days and 28 days after PVE. Secondary outcomes included posthepatectomy liver failure, surgical complications, and length of intensive care treatment and hospital stay. The Mann-Whitney U test was used to compare continuous outcomes according to PVE material, whereas the Χ² test or Fisher exact test was used for categoric variables. Results Sixty participants (mean age, 61 years ± 11 [standard deviation]; 32 men) were assigned to the PVA particles plus coils group (n = 30) or to the NBCA plus iodized oil group (n = 30). Interim analysis revealed faster and superior liver hypertrophy for the NBCA plus iodized oil group versus the PVA particles plus coils group 14 days and 28 days after PVE (absolute hypertrophy of 46% vs 30% [P < .001] and 57% vs 37% [P < .001], respectively). Liver growth for the proposed hepatectomy was achieved in 87% of participants (26 of 30) in the NBCA plus iodized oil group versus 53% of participants (16 of 30) in the PVA particles plus coils group (P = .008) 14 days after PVE. Liver failure occurred in 13% of participants (three of 24) in the NBCA plus iodized oil group and in 27% of participants (six of 22) in the PVA particles plus coils group (P = .27). Conclusion Portal vein embolization with N-butyl-cyanoacrylate plus iodized oil produced greater and faster liver growth as seen at CT in participants with liver cancer, compared with portal vein embolization with polyvinyl alcohol particles plus coils, allowing for earlier surgical intervention. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Arellano in this issue.

The value of a combined radiological-surgical approach in allowing curative resection of a locally advanced type IIIa Klatskin tumor

We report the case of a 53-year-old patient subjected to percutaneous embolization of right and middle hepatic veins to induce liver segments 2–3 hypertrophy before extended right hepatic resection for a locally advanced type IIIa perihilar cholangiocarcinoma.

Hepatic vein embolization (HVE) was performed 3 weeks after surgical recanalization of left portal vein (severely narrowed at its origin due to tumor infiltration) interposing an internal jugular vein graft between main and distal left portal vein.

Nine days after HVE, future liver remnant volume increased from 395 to 501 cc, i.e. 25.1% of standardized total liver volume, allowing to perform a radical right hepatic trisectionectomy plus caudatectomy. He was discharged home on postoperative day 15th after an uneventful postoperative course, with no sign of posthepatectomy liver failure.

Induction of liver hypertrophy for extended liver surgery and partial liver transplantation: State of the art of parenchyma augmentation-assisted liver surgery

Background

Liver surgery and transplantation currently represent the only curative treatment options for primary and secondary hepatic malignancies. Despite the ability of the liver to regenerate after tissue loss, 25–30% future liver remnant is considered the minimum requirement to prevent serious risk for post-hepatectomy liver failure.

Purpose

The aim of this review is to depict the various interventions for liver parenchyma augmentation–assisting surgery enabling extended liver resections. The article summarizes one- and two-stage procedures with a focus on hypertrophy- and corresponding resection rates.

Conclusions

To induce liver parenchymal augmentation prior to hepatectomy, most techniques rely on portal vein occlusion, but more recently inclusion of parenchymal splitting, hepatic vein occlusion, and partial liver transplantation has extended the technical armamentarium. Safely accomplishing major and ultimately total hepatectomy by these techniques requires integration into a meaningful oncological concept. The advent of highly effective chemotherapeutic regimen in the neo-adjuvant, interstage, and adjuvant setting has underlined an aggressive surgical approach in the given setting to convert formerly “palliative” disease into a curative and sometimes in a “chronic” disease.

Preoperative portal vein or portal and hepatic vein embolization: DRAGON collaborative group analysis

BACKGROUND

The extent of liver resection for tumours is limited by the expected functional reserve of the future liver remnant (FRL), so hypertrophy may be induced by portal vein embolization (PVE), taking 6 weeks or longer for growth. This study assessed the hypothesis that simultaneous embolization of portal and hepatic veins (PVE/HVE) accelerates hypertrophy and improves resectability.

METHODS

All centres of the international DRAGON trials study collaborative were asked to provide data on patients who had PVE/HVE or PVE on 2016-2019 (more than 5 PVE/HVE procedures was a requirement). Liver volumetry was performed using OsiriX MD software. Multivariable analysis was performed for the endpoints of resectability rate, FLR hypertrophy and major complications using receiver operating characteristic (ROC) statistics, regression, and Kaplan-Meier analysis.

RESULTS

In total, 39 patients had undergone PVE/HVE and 160 had PVE alone. The PVE/HVE group had better hypertrophy than the PVE group (59 versus 48 per cent respectively; P = 0.020) and resectability (90 versus 68 per cent; P = 0.007). Major complications (26 versus 34 per cent; P = 0.550) and 90-day mortality (3 versus 16 per cent respectively, P = 0.065) were comparable. Multivariable analysis confirmed that these effects were independent of confounders.

CONCLUSION

PVE/HVE achieved better FLR hypertrophy and resectability than PVE in this collaborative experience.