Comparative study of right portal vein ligation versus embolisation for induction of hypertrophy in two-stage hepatectomy for multiple bilateral colorectal liver metastases

Efficacy and perioperative safety of different future liver remnant modulation techniques: a systematic review and network meta-analysis

BACKGROUND

In daily clinical practice, different future liver remnant (FLR) modulation techniques are increasingly used to allow a liver resection in patients with insufficient FLR volume. This systematic review and network meta-analysis aims to compare the efficacy and perioperative safety of portal vein ligation (PVL), portal vein embolization (PVE), liver venous deprivation (LVD) and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS).

METHODS

A literature search for studies comparing liver resections following different FLR modulation techniques was performed in MEDLINE, Embase and Cochrane Central, and pairwise and network meta-analyses were conducted.

RESULTS

Overall, 23 studies comprising 1557 patients were included. LVD achieved the greatest increase in FLR (17.32 %, 95% CI 2.49-32.15), while ALPPS was most effective in preventing dropout before the completion hepatectomy (OR 0.29, 95% CI 0.15-0.55). PVL tended to be associated with a longer time to completion hepatectomy (MD 5.78 days, 95% CI -0.67-12.23). Liver failure occurred less frequently after LVD, compared to PVE (OR 0.35, 95% CI 0.14-0.87) and ALPPS (OR 0.28, 95% CI 0.09-0.85).

DISCUSSION

ALPPS and LVD seem superior to PVE and PVL in terms of achieved FLR increase and subsequent treatment completion. LVD was associated with lower rates of post hepatectomy liver failure, compared to both PVE and ALPPS. A summary of the protocol has been prospectively registered in the PROSPERO database (CRD42022321474).

Right portal vein ligation is still relevant for left hemi-liver hypertrophy: results of a comparative study using a propensity score between right portal vein ligation and embolization

BACKGROUND

In two-stage hepatectomy for bilobar liver metastases from colorectal cancer, future liver remnant (FLR) growth can be achieved using several techniques, such as right portal vein ligation (RPVL) or right portal vein embolization (RPVE). A few heterogeneous studies have compared these two techniques with contradictory results concerning FLR growth. The objective of this study was to compare FLR hypertrophy of the left hemi-liver after RPVL and RPVE.

STUDY DESIGN

This was a retrospective comparative study using a propensity score of patients who underwent RPVL or RPVE prior to major hepatectomy between January 2010 and December 2020. The endpoints were FLR growth (%) after weighting using the propensity score, which included FLR prior to surgery and the number of chemotherapy cycles. Secondary endpoints were the percentage of patients undergoing simultaneous procedures, the morbidity and mortality, the recourse to other liver hypertrophy procedures, and the number of invasive procedures for the entire oncologic program in intention-to-treat analysis.

RESULTS

Fifty-four consecutive patients were retrospectively included and analyzed, 18 in the RPVL group, and 36 in the RPVE group. The demographic characteristics were similar between the groups. After weighting, there was no significant difference between the RPVL and RPVE groups for FLR growth (%), respectively 32.5% [19.3-56.0%] and 34.5% [20.5-47.3%] (p = 0.221). There was no significant difference regarding the secondary outcomes except for the lower number of invasive procedures in RPVL group (median of 2 [2.0, 3.0] in RPVL group and 3 [3.0, 3.0] in RPVE group, p = 0.001)).

CONCLUSION

RPVL and RPVE are both effective to provide required left hemi-liver hypertrophy before right hepatectomy. RPVL should be considered for the simultaneous treatment of liver metastases and the primary tumor.

Efficacy and safety of different options for liver regeneration of future liver remnant in patients with liver malignancies: a systematic review and network meta-analysis

BACKGROUND

Several treatments induce liver hypertrophy for patients with liver malignancies but insufficient future liver remnant (FLR). Herein, the aim of this study is to compare the efficacy and safety of existing surgical techniques using network meta-analysis (NMA).

METHODS

We searched PubMed, Web of Science, and Cochrane Library from databases for abstracts and full-text articles published from database inception through Feb 2022. The primary outcome was the efficacy of different procedures, including standardized FLR (sFLR) increase, time to hepatectomy, resection rate, and R0 resection margin. The secondary outcome was the safety of different treatments, including the rate of Clavien-Dindo≥3a and 90-day mortality.

RESULTS

Twenty-seven studies, including three randomized controlled trials (RCTs), three prospective trials (PTs), and twenty-one retrospective trials (RTs), and a total number of 2075 patients were recruited in this study. NMA demonstrated that the Associating Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS) had much higher sFLR increase when compared to portal vein embolization (PVE) (55.25%, 95% CI 45.27-65.24%), or liver venous deprivation(LVD) (43.26%, 95% CI 22.05-64.47%), or two-stage hepatectomy (TSH) (30.53%, 95% CI 16.84-44.21%), or portal vein ligation (PVL) (58.42%, 95% CI 37.62-79.23%). ALPPS showed significantly shorter time to hepatectomy when compared to PVE (-32.79d, 95% CI -42.92-22.66), or LVD (-34.02d, 95% CI -47.85-20.20), or TSH (-22.85d, 95% CI -30.97-14.72), or PVL (-43.37d, 95% CI -64.11-22.62); ALPPS was considered as the highest resection rate when compared to TSH (OR=6.09; 95% CI 2.76-13.41), or PVL (OR =3.52; 95% CI 1.16-10.72), or PVE (OR =4.12; 95% CI 2.19-7.77). ALPPS had comparable resection rate with LVD (OR =2.20; 95% CI 0.83-5.86). There was no significant difference between them when considering the R0 marge rate. ALPPS had a higher Clavien-Dindo≥3a complication rate and 90-day mortality compared to other treatments, although there were no significant differences between different procedures.

CONCLUSIONS

ALPPS demonstrated a higher regeneration rate, shorter time to hepatectomy, and higher resection rate than PVL, PVE, or TSH. There was no significant difference between them when considering the R0 marge rate. However, ALPPS developed the trend of higher Clavien-Dindo≥3a complication rate and 90-day mortality compared to other treatments.

Minimizing the risk of small-for-size syndrome after liver surgery

BACKGROUND

Primary and secondary liver tumors are not always amenable to resection due to location and size. Inadequate future liver remnant (FLR) may prevent patients from having a curative resection or may result in increased postoperative morbidity and mortality from complications related to small-for-size syndrome (SFSS).

DATA SOURCES

This comprehensive review analyzed the principles, mechanism and risk factors associated with SFSS and presented current available options in the evaluation of FLR when planning liver surgery. In addition, it provided a detailed description of specific modalities that can be used before, during or after surgery, in order to optimize the conditions for a safe resection and minimize the risk of SFSS.

RESULTS

Several methods which aim to reduce tumor burden, preserve healthy liver parenchyma, induce hypertrophy of FLR or prevent postoperative complications help minimize the risk of SFSS.

CONCLUSIONS

With those techniques the indications of radical treatment for patients with liver tumors have significantly expanded. The successful outcome depends on appropriate patient selection, the individualization and modification of interventions and the right timing of surgery.

Shifting concepts in the management of colorectal liver metastases

Management of patients with colorectal liver metastases has evolved considerably due to a better understanding of the biology of the disease with concurrent improvements in surgical techniques, oncological strategies and radiological interventions. This review article examines the factors that have contributed to this radical change. Management will be discussed in relation to chemotherapy, surgery and interventional radiology. The addition of chemotherapy and biological agents has greatly extended the reach and scope of surgery. Parenchymal sparing resections, repeat resections, two stage hepatectomy and Associating Liver Partition and Portal Vein ligation are all available to the hepatobiliary surgeon who deals with colorectal liver metastases. Interventional radiology techniques like liver venous deprivation may also replace established surgical practice. Whilst traditionally it was thought that only a few liver metastases could be treated effectively, nowadays tumour number is no longer a limiting factor provided enough functioning liver can be spared and the patient can tolerate the operation.

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.

Portal vein embolization with ethylene-vinyl alcohol copolymer for contralateral lobe hypertrophy before liver resection: safety, feasibility and initial experience

Background

To report our preliminary experience with preoperative portal vein embolization (PVE) using liquid ethylene vinyl alcohol (EVOH) copolymer.

Methods

Retrospectively review of patients with primary or secondary liver malignancies scheduled for extensive hepatectomy after the induction of future liver remnant (FLR) hypertrophy by right or left PVE with EVOH as the only embolic agent between 2014 and 2018 at two academic centers. Cross-sectional imaging liver volumetry data obtained before and 3-6 weeks after PVE were used to assess the FLR volume (FLRV) increase, degree of FLR hypertrophy and the FLR kinetic growth rate (KGR).

Results

Twenty-six patients (17 males; mean age, 58.7±11 years; range, 32-79 years) were included. The technical and clinical success rate was 100%. PVE produced adequate FLR hypertrophy in all patients. Embolization occurred in all targeted portal branches and in no non-target vessels. The %FLRV increased by 52.9%±32.5% and the degree of FLR hypertrophy was 16.7%±6.8%. The KGR was 4.4%±2.0% per week. Four patients experience minor complications after PVE which resolved with symptomatic treatment. The resection rate was 84.5%. One patient died during surgery for reasons unrelated to PVE.

Conclusions

Preoperative PVE with EVOH copolymer is feasible, safe, and effective in inducing FLR hypertrophy.

No difference in mortality among ALPPS, two-staged hepatectomy, and portal vein embolization/ligation: A systematic review by updated traditional and network meta-analyses

BACKGROUND

There is an ongoing debate on the feasibility, safety, and oncological efficacy of the associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) technique. The aim of this study was to compare ALPPS, two-staged hepatectomy (TSH), and portal vein embolization (PVE)/ligation (PVL) using updated traditional meta-analysis and network meta-analysis (NMA).

DATA SOURCES

Electronic databases were used in a systematic literature search. Updated traditional meta-analysis and NMA were performed and compared. Mortality and major morbidity were selected as primary outcomes.

RESULTS

Nineteen studies including 1200 patients were selected from the pool of 436 studies. Of these patients, 315 (31%) and 702 (69%) underwent ALPPS and portal vein occlusion (PVO), respectively. Ninety-day mortality based on updated traditional meta-analysis, subgroup analysis of the randomized controlled trials (RCTs), and both Bayesian and frequentist NMA did not demonstrate significant differences between the ALPPS cohort and the PVE, PVL, and TSH cohorts. Moreover, analysis of RCTs did not demonstrate significant differences of major morbidity between the ALPPS and PVO cohorts. The ALPPS cohort demonstrated significantly more favorable outcomes in hypertrophy parameters, time to operation, definitive hepatectomy, and R0 margins rates compared with the PVO cohort. In contrast, 1-year disease-free survival was significantly higher in the PVO cohort compared to the ALPPS cohort.

CONCLUSIONS

This study is the first to use updated traditional meta-analysis and both Bayesian and frequentist NMA and demonstrated no significant differences in 90-day mortality between the ALPPS and other hepatic hypertrophy approaches. Furthermore, two high quality RCTs including 147 patients demonstrated no significant differences in major morbidity between the ALPPS and PVO cohorts.

Long-Term Outcome After Conventional Two-Stage Hepatectomy Versus Tourniquet-ALPPS in Colorectal Liver Metastases: A Propensity Score Matching Analysis

BACKGROUND

To compare the overall survival (OS) and disease-free survival (DFS) of Tourniquet-ALPPS (T-ALPPS) and conventional two-stage hepatectomy (TSH) in patients with colorectal liver metastases (CRLM).

METHODS

A retrospective study from a prospectively collected database was performed between October 2000 and July 2016. TSH was performed before September 2011, after which time T-ALPPS became the technique of choice. A propensity score matching (PSM) was performed based on a 1:1 ratio with consideration of the following variables: number and size of metastases, bilobar disease presence, and chemotherapy received.

RESULTS

Thirty-four patients received T-ALPPS; 41 patients received TSH. After PSM, 21 patients remained in each group, with 100% resectability in the T-ALPPS group and 90.5% resectability in the TSH group. The median OS for TSH was 41 months; for T-ALPPS, the median OS was 36 months (P = 0.925). The median DFS was 16 months in the TSH group; the median DFS was 9 months in the T-ALPPS group (P = 0.930). The 1-, 3-, and 5-year OS for TSH was 81%, 66.7%, and 23.8% vs. 76.2%, 57.1%, and 22.9% for T-ALPPS, respectively. The 1-, 3-, and 5-year DFS for TSH was 66.7%, 9.5%, and 5% vs. 44.6%, 11.1%, and 11.1% for T-ALPPS, respectively. The volume increase with T-ALPPS was superior to that with TSH (68% vs. 39%; P = 0.018). There were no differences in morbidity and mortality after stages 1 and 2.

CONCLUSIONS

T-ALPPS produces a similar outcome to TSH, indicating that it could be a safe and effective alternative for curative hepatectomy for all patients.

Hepatic metastasis from colorectal cancer

Colorectal cancer (CRC) is one of the most common cancers in the world. About two third of patients with CRC will develop distant recurrence at some point in time. Liver is the most common site where distant metastasis takes place. While the overall survival (OS) of patients with metastatic CRC was poor about 3 decades ago, there has been tremendous improvement in this area in the recent years. With the advent of effective systemic chemotherapy and biologic agents and better understanding of the biological behaviour of the tumour, aggressive treatment strategies such as metastatectomy of the liver metastases (or lung metastases) are now acceptable. More importantly, it has transformed the way how stage IV CRCs are being managed. From predominantly palliative as the primary aim, a comprehensive multidisciplinary approach is now the mainstay of treatment with very successful outcomes. Combination of systemic therapies with liver resection has been shown to be effective in providing promising survival benefits. In addition, other adjunctive modalities in targeting the liver metastases such as ablation, combining resection and ablation, transarterial chemoembolization, stereotactic body radiotherapy (SBRT), hepatic artery perfusion, etc. have also been demonstrated variable outcome in treating colorectal liver metastasis (CRLM). Very recently, transplant oncologists have also explored using liver transplantation as a treatment modality for unresectable CRLM, which has demonstrated very good long-term survival in well selected cases. The new paradigm in the treatment of metastatic CRC has dawned.

Transplantation versus liver resection in patients with hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common solid cancers in the world. Its treatment strategies have evolved significantly over the past few decades but the best treatment outcomes remain in the surgical arena. Especially for early HCCs, the options are abundant. However, surgical resection and liver transplantation provide the best long-term survival. In addition, there are evidence the ablative therapy such as radiofrequency ablation, could provide equivalent outcome as compared to resection. However, HCC is a unique malignancy as the majority of patients develop this cancer in the background of cirrhotic livers. As such, the treatment consideration should not only look at the oncological perspective but also the functional status of the liver parenchyma, i.e., the state of cirrhosis and presence of portal hypertension. Even with the most widely adopted staging systems for HCC such as the Barcelona Clinic Liver Cancer (BCLC) staging system and many other staging systems, none of them are ideal in including the various considerations for patients with HCCs. In this article, the key issues between choosing surgical resection and liver transplantation are discussed. A comprehensive review of the current surgical options are outlined in order to explore the pros and cons of each option.

Dealing with an insufficient future liver remnant: Portal vein embolization and two-stage hepatectomy

Colorectal liver metastases (CLM) are not always resectable at the time of diagnosis. An insufficient future liver remnant is a factor excluding patients from curative intent resection. To deal with this issue, two-stage hepatectomy was introduced approximately 20 years ago. It is a sequential treatment strategy for bilateral CLM, which consists of preoperative chemotherapy, portal vein embolization, and planned first and second liver resections. This study reviews current evidence supporting use of two-stage hepatectomy.

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.

Resection for intrahepatic cholangiocellular cancer: new advances

Intrahepatic cholangiocarcinoma (ICC) is the second most prevalent primary liver neoplasm after hepatocellular carcinoma (HCC), corresponding to 10% to 15% of cases. Pathologies that cause chronic biliary inflammation and bile stasis are known predisposing factors for development of ICC. The incidence and cancer-related mortality of ICC is increasing worldwide. Most patients remain asymptomatic until advance stage, commonly presenting with a liver mass incidentally diagnosed. The only potentially curative treatment available for ICC is surgical resection. The prognosis is dismal for unresectable cases. The principle of the surgical approach is a margin negative hepatic resection with preservation of adequate liver remnant. Regional lymphadenectomy is recommended at time of hepatectomy due to the massive impact on outcomes caused by lymph node (LN) metastasis. Multicentric disease, tumor size, margin status and tumor differentiation are also important prognostic factors. Staging laparoscopy is warranted in high-risk patients to avoid unnecessary laparotomy. Exceedingly complex surgical procedures, such as major vascular, extrahepatic bile ducts and visceral resections, ex vivo hepatectomy and autotransplantation, should be implemented in properly selected patients to achieve negative margins. Neoadjuvant therapy may be used in initially unresectable lesions in order to downstage and allow resection. Despite optimal surgical management, recurrence is frustratingly high. Adjuvant chemotherapy with radiation associated with locoregional treatments should be considered in cases with unfavorable prognostic factors. Selected patients may undergo re-resection of tumor recurrence. Despite the historically poor outcomes of liver transplantation for ICC, highly selected patients with unresectable disease, especially those with adequate response to neoadjuvant therapy, may be offered transplant. In this article, we reviewed the current literature in order to highlight the most recent advances and recommendations for the surgical treatment of this aggressive malignancy.

Alcohol injection into the portal vein prior to ligation increases liver regeneration rate

BACKGROUND

Failure of portal vein ligation (PVL) to induce hypertrophy is not uncommon. The aim of the study was to evaluate the impact of intraportal alcohol injection prior to ligation on liver regeneration.

METHOD

Forty-two patients with colorectal liver metastases who underwent PVL between 01/2004 and 06/2014 were analyzed. Beginning in 09/2011, alcohol was injected prior to PVL. Patients treated with PVL alone (Alc- group) were compared with those treated with alcohol injection plus PVL (Alc+ group). Liver regeneration was assessed by volumetric increase (VI).

RESULTS

Alc+ (23 patients) and Alc- (19 patients) groups were similar in terms of age, sex and pre-PVL FLRV. Alc- group had a higher risk of recanalization (12 vs. 1, p < 0.001) and cavernous transformation (7 vs. 2, p = 0.055) of the occluded portal vein. Post-PVL FLRV (43.3 ± 14.3% vs. 34.6 ± 6.4%, p = 0.013) and VI (0.44 ± 0.24 vs. 0.28 ± 0.20, p = 0.029) were higher in Alc+ group. On multivariate analysis male sex (B = -0.149) and alcohol injection (B = 0.143) significantly predicted VI.

CONCLUSIONS

Alcohol injection prior to PVL may increase the regeneration of the FLRV by reducing the recanalization of the occluded portal vein.

Tourniquet-ALPPS is a promising treatment for very large hepatocellular carcinoma and intrahepatic cholangiocarcinoma

When very large hepatocellular carcinomas (HCCs) and intrahepatic cholangiocarcinoma (IHCCs) with insufficient future liver remnants are treated using associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), the outcome is often poor. We therefore tested the efficacy of a modified version of that technique, tourniquet-ALPPS. A review of the literature examining outcomes of HCC and IHCC patients treated with ALPPS revealed the incidences of morbidity ≥ III and postoperative mortality to be respectively 20.7% and 16.1% among HCC patients and 50% and 45.4% among IHCC patients. In the present case series, in which HCC and IHCC patients were treated with tourniquet-ALPPS, median tumor size was 100 mm (range: 70–200 mm). After surgical stage I, there was no morbidity, no mortality and the median future liver remnant had increased at day 7 by 76%. In surgical stage II, 100% of tumors were resectable (8 right trisectionectomies, 5 with inferior vena cava resection). Two patients experienced serious morbidity ≥ IIIB and 1 patient died (11%). One- and 3-year overall survival was 75% and 60%, respectively. Thus tourniquet-ALPPS appears to be an effective alternative to classical ALPPS for the treatment of patients with HCC or IHCC.

[Associated Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS) in focal liver diseases management]

AIM

To determine ALPPS advisability in small future remnant liver.

MATERIAL AND METHODS

22 ALPPS procedures were performed at the Center for Surgery and Transplantology for the period from 2011 to 2016. Indications were both tumoral and non-tumoral unresectable liver diseases. Postoperative complications were classified according to Clavien-Dindo, ISGLS.

RESULTS

According to CT-volumetry future remnant liver before the 1^st stage of ALPPS was from 17 to 25%, before the 2^nd stage - from 28 to 49%. Both stages were carried out in all patients with R0-resection in 100%. Postoperative complications were diagnosed in 40.9%, 1 death was caused by severe pulmonary embolism. Follow-up varied from 3 to 48 months (median 17.5), 86% of patients are alive at present.

CONCLUSION

ALPPS provides rapid and effective FLR growth and can be used for both tumoral and non-tumoral unresectable liver diseases. However, ALPPS should be performed strictly according to indications and only in specialized centers with extensive experience of advanced liver resection and transplantation after previous comprehensive selection of patients.

Assessment and optimization of liver volume before major hepatic resection: Current guidelines and a narrative review

Post hepatectomy liver failure (PHLF) remains a significant cause of morbidity and mortality after major liver resection. Although the etiology of PHLF is multifactorial, an inadequate functional liver remnant (FLR) is felt to be the most important modifiable predictor of PHLF. Pre-operative evaluation of FLR function and volume is of paramount importance before proceeding with any major liver resection. Patients with inadequate or borderline FLR volume must be considered for volume optimization strategies such as portal vein embolization (PVE), two stage hepatectomy with portal vein ligation (PVL), Yttrium-90 radioembolization, and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). This paper provides an overview of assessing FLR volume and function, and discusses indications and outcomes of commonly used volume optimization strategies.

Portal vein ligation versus portal vein embolization for induction of hypertrophy of the future liver remnant: A systematic review and meta-analysis

An important risk of major hepatic resection is postoperative liver failure, which is directly related to insufficient future liver remnant (FLR). Portal vein embolization (PVE) and portal vein ligation (PVL) can minimize this risk by inducing hypertrophy of the FLR. The aim of this systematic review and meta-analysis was to compare the efficacy and safety of PVE and PVL for FLR hypertrophy. A systematic search was conducted on the17^th of January 2017. The methodological quality of the studies was assessed using the Oxford Critical Appraisal Skills Program for cohort studies. The primary endpoint was the relative rate of hypertrophy of the FLR. Number of cancelled hepatic resection and postoperative morbidity and mortality were secondary endpoints. For meta-analysis, the pooled hypertrophy rate was calculated for each intervention. The literature search identified 21 eligible studies with 1953 PVE and 123 PVL patients. All studies were included in the meta-analysis. No significant differences were found regarding the rate of FLR hypertrophy (PVE 43.2%, PVL 38.5%, p = 0.39). The number of cancelled hepatic resections due to inadequate hypertrophy was significantly lower after PVL (p = 0.002). No differences were found in post-intervention mortality and morbidity. This meta-analysis demonstrated no significant differences in safety and rate of FLR hypertrophy between PVE and PVL. PVE should be considered as the preferred strategy, since it is a minimally invasive procedure. However, during a two-stage procedure, PVL can be performed with expected comparable outcome as PVE.

[Portal vein embolization: Present and future]

Portal vein embolization consists of occluding a part of the portal venous system in order to achieve the hypertrophy of the non-embolized liver segments. This technique is used during the preoperative period of major liver resection when the future remnant liver (FRL) volume is insufficient, exposing to postoperative liver failure, main cause of death after major hepatectomy. Portal vein embolization indication depends on the FRL, commonly assessed by its volume. Nowadays, FRL function evaluation seems more relevant and can be measured by 99mTc labelled mebrofenin scintigraphy. Portal vein embolization procedure is mostly performed with percutaneous trans-hepatic access by using ultrasonography guidance and consists of embolic agent injection, such as cyanoacrylate, in the targeted portal vein branches with fluoroscopic guidance. It is a safe and well-tolerated technique, with extremely low morbi-mortality. Portal vein embolization leads to sufficient FRL hypertrophy in about 80% of patients, allowing them to undergo surgery from which they were initially rejected. The two main reasons of non-resection are tumor progression (≈15% of cases) and FRL insufficient hypertrophy (≈5% of cases). When portal vein embolization is not enough to obtain adequate FRL regeneration, hepatic vein embolization may potentiate its effect (liver venous deprivation technique).

Current status and future perspectives on treatment of liver metastasis in colorectal cancer (Review)

Liver metastasis is the most common site of colorectal cancer (CRC) metastasis. Approximately half of all colorectal cancer patients will develop liver metastases. Although radical surgery is the standard treatment modality, only 10-20% of patients are deemed eligible for resection. Despite advances in survival with chemotherapy, surgical resection is still considered the only curative option for patients with liver metastases. Much effort has been expended to address patients with metastatic liver disease. The majority of evidence stated a significant survival benefit with surgical resection to reach an overall 5-year survival rate of 35-55% after hepatic resection. However, still majority of patients will experience disease recurrence even after a successful resection. In this review, we describe current status and controversies related to treatment options for CRC liver metastases and its potential for enhancing oncologic outcomes and improving quality of life.

Dynamic Evaluation of Liver Volume and Function in Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy

BACKGROUND

Despite a fast and potent growth of the future liver remnant (FLR), patients operated with associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) are at risk of developing posthepatectomy liver failure. In this study, the relation between liver volume and function in ALPPS was studied using a multimodal assessment.

METHODS

Nine patients with colorectal liver metastases treated with neoadjuvant chemotherapy and operated with ALPPS were studied with hepatobiliary scintigraphy, computed tomography, indocyanine green clearance test, and serum liver function tests. A comparison between liver volume and function was conducted.

RESULTS

The preoperative FLR volume of 19.5% underestimated the preoperative FLR function of 25.3% (p = 0.011). The increase in FLR volume exceeded the increase in function at day 6 after stage 1 (FLR volume increase 56.7% versus FLR function increase 28.2%, p = 0.021), meaning that the increase in function was 50% of the increase in volume. After stage 2, functional increase exceeded the volume increase, resulting in similar values 28 days after stage 2.

CONCLUSIONS

In the inter-stage period of ALPPS, the high volume increase is not paralleled by a corresponding functional increase. This may in part explain the high morbidity and mortality rates associated with ALPPS. Functional assessment of the FLR is advised.

Two-stage hepatectomy in two regional district community hospitals: perioperative safety and long-term survival

INTRODUCTION

Surgical resection offers the best chance of cure for patients with colorectal liver metastases (CRLMs). Two-stage hepatectomy (TSH) has been demonstrated to be safe and effective to obtain curative resection in patients with multiple, bilobar CRLMs that are unresectable in a single procedure. Up to now TSH has been the prerogative of dedicated liver surgery centers. The aim of this study was to assess the safety and effectiveness of TSH also in community hospitals.

METHODS

Of 294 patients operated on for CRLMs between September 1997 and June 2012 in 2 district community hospitals (belonging to the same regional healthcare district), 43 (14.6%) were scheduled for TSH. Thirty-eight/43 received neoadjuvant and/or bridge chemotherapy (2 neoadjuvant only, 4 neoadjuvant and bridge, 32 bridge only).

RESULTS

The mean follow-up was 35.74 ± 29.53 months. Five-year overall survival (OS) was 31.4%, with a median survival time of 31 months. Twenty-nine patients completed the planned procedure (OS: 42.9%; median 47 months), while 14 did not because of disease progression (OS: 0%; median 13 months). No operative mortality occurred within the first 90 days either after the first or second stage.

CONCLUSIONS

Our results suggest good efficacy and safety of TSH even when performed in a community hospital setting. Shifting patient selection from neoadjuvant to bridge chemotherapy had no impact on outcome once the clearing of the liver had been achieved. In patients presenting with synchronous CRLMs, simultaneous colorectal resection and clearing of the less involved hemiliver as the first surgical step is feasible without any negative impact on outcome.

Meta-analysis of associating liver partition with portal vein ligation and portal vein occlusion for two-stage hepatectomy

BACKGROUND

Discussion is ongoing regarding whether associating liver partition with portal vein ligation for staged hepatectomy (ALPPS) or portal vein occlusion is better in staged hepatectomy. The aim of this study was to compare available strategies using a two-stage approach in extended hepatectomy.

METHODS

A literature search was performed in MEDLINE, Scopus, the Cochrane Library and Embase, and additional articles were identified by hand searching. Data from the international ALPPS registry were extracted. Clinical studies reporting volumetric changes, mortality, morbidity, feasibility of the second stage and tumour-free resection margins (R0) in two-stage hepatectomy were included.

RESULTS

Ninety studies involving 4352 patients, including 320 from the ALPPS registry, met the inclusion criteria. Among these, nine studies (357 patients) reported on comparisons with other strategies. In the comparison of ALPPS versus portal vein embolization (PVE), ALPPS was associated with a greater increase in the future liver remnant (76 versus 37 per cent; P < 0·001) and more frequent completion of stage 2 (100 versus 77 per cent; P < 0·001). Compared with PVE, ALPPS had a trend towards higher morbidity (73 versus 59 per cent; P = 0·16) and mortality (14 versus 7 per cent; P = 0·19) after stage 2. In the non-comparative studies, complication rates were 39 per cent in the PVE group, 47 per cent in the portal vein ligation (PVL) group and 70 per cent in the ALPPS group. After stage 2, mortality rates were 5, 7 and 12 per cent respectively.

CONCLUSION

ALPPS is associated with greater future liver remnant hypertrophy and a higher rate of completion of stage 2, but this may be at the price of greater morbidity and mortality.

Controversies of preoperative portal vein embolization

Portal vein embolization (PVE) is a safe, percutaneous procedure that has been proven to lower the complication rates of curative intent large-volume hepatic resection by inducing hypertrophy of the future liver remnant. While the safety and efficacy of PVE has been well substantiated, there remains controversy with regards to the technical details, periprocedural management, and whether alternative methods of achieving future liver remnant hypertrophy are preferable to PVE. This paper will address those controversies and offer recommendations based on available data.

Liver-fat and liver-function indices derived from Gd-EOB-DTPA-enhanced liver MRI for prediction of future liver remnant growth after portal vein occlusion

OBJECTIVES

To evaluate the use of Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI)-derived fat- and liver function-measurements for prediction of future liver remnant (FLR) growth after portal vein occlusion (PVO) in patients scheduled for major liver resection.

METHODS

Forty-five patients (age, 59 ± 13.9 y) who underwent Gd-EOB-DTPA-enhanced liver MRI within 24 ± 18 days prior to PVO were included in this study. Fat-Signal-Fraction (FSF), relative liver enhancement (RLE) and corrected liver-to-spleen ratio (corrLSR) of the FLR were calculated from in- and out-of-phase (n=42) as well as from unenhanced T1-weighted, and hepatocyte-phase images (n=35), respectively. Kinetic growth rate (KGR, volume increase/week) of the FLR after PVO was the primary endpoint. Receiver operating characteristics analysis was used to determine cutoff values for prediction of impaired FLR-growth.

RESULTS

FSF (%) showed significant inverse correlation with KGR (r=-0.41, p=0.008), whereas no significant correlation was found with RLE and corrLSR. FSF was significantly higher in patients with impaired FLR-growth than in those with normal growth (%FSF, 8.1 ± 9.3 vs. 3.0 ± 5.9, p=0.02). ROC-analysis revealed a cutoff-FSF of 4.9% for identification of patients with impaired FLR-growth with a specificity of 82% and sensitivity of 47% (AUC 0.71 [95%CI:0.54-0.87]). Patients with impaired FLR-growth according to the FSF-cutoff showed a tendency towards higher postoperative complication rates (posthepatectomy liver failure in 50% vs. 19%).

CONCLUSIONS

Liver fat-content, but not liver function derived from Gd-EOB-DTPA-enhanced MRI is a predictor of FLR-growth after PVO. Thus, liver MRI could help in identifying patients at risk for insufficient FLR-growth, who may need re-evaluation of the therapeutic strategy.

Staged resection of bilobar colorectal liver metastases: surgical strategies

BACKGROUND

Radical resection is the treatment of choice for colorectal liver metastases (CLM). Unfortunately, only about 20 % of patients present with initially resectable disease, in most cases due to bilobar disease. In the last two decades, major achievements have been made to extend surgical indications to patients with bilobar CLM, such as two-stage hepatectomy with or without portal vein occlusion and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS).

PURPOSE

The purpose of this review article was to summarize current surgical approaches and their safety and efficacy for patients with initially unresectable bilobar CLM.

CONCLUSION

In selected patients, two-stage hepatectomy and ALPPS are efficient and safe to convert unresectable to resectable CLM. Further studies are required to evaluate long-term outcome of these procedures.

Role of associating liver partition and portal vein ligation for staged hepatectomy in colorectal liver metastases: A review

Colorectal cancer is the third most common cancer in the Western world. Approximately half of patients will develop liver metastases, which is the most common cause of death. The only potentially curative treatment is surgical resection. However, many patients retain a to small future liver remnant (FLR) to allow for resection directly. There are therefore strategies to decrease the tumor with neoadjuvant chemotherapy and to increase the FLR. An accepted strategy to increase the FLR is portal vein occlusion (PVO). A concern with this strategy is that a large proportion of patients will never be operated because of progression during the interval between PVO and resection. ALPPS (associating liver partition and portal vein ligation for staged hepatectomy) is a new procedure with a high resection rate. A concern with this approach is the rather high frequency of complications and high mortality, compared to PVO. In this review, it is shown that with ALPPS the resection rate was 97.1% for CRLM and the mortality rate for all diagnoses was 9.6%. The mortality rate was likely lower for patients with CRLM, but some data were lacking in the reports. Due to the novelty of ALPPS, the indications and technique are not yet established but there are arguments for ALPPS in the context of CRLM and a small FLR.

Volume regeneration of segments 2 and 3 after right portal vein embolization in patients undergoing two-stage hepatectomy

BACKGROUND

The impact of first-stage resection on volume regeneration of segments 2 and 3 (2 + 3) after right portal vein embolization (RPVE) in patients undergoing two-stage right hepatectomy has not been investigated.

METHOD

Volume data for segments 2 + 3 were compared between 44 patients undergoing two-stage hepatectomy and 116 undergoing single-stage hepatectomy after RPVE.

RESULTS

The degree of hypertrophy (difference between standardized volume of segments 2 + 3 before and after RPVE) and kinetic growth rate (degree of hypertrophy at initial volume assessment divided by the number of weeks elapsed after RPVE) were significantly lower in patients undergoing two-stage hepatectomy (median 8.6 vs 10.5% [p = 0.01] and 1.7 vs 2.4% [p < 0.01], respectively). Resection volume during first-stage resection was negatively correlated with standardized volume increase from the volume before first-stage resection (R (2) 0.546, p < 0.01). In patients undergoing two-stage hepatectomy after RPVE with segment 4 embolization, the degree of hypertrophy and kinetic growth rate were similar to those in patients undergoing single-stage hepatectomy (p = 0.17 and p = 0.08, respectively).

CONCLUSION

In patients undergoing two-stage hepatectomy, first-stage resection impairs the dynamics of volume regeneration of segments 2 + 3 after RPVE. When two-stage extended right hepatectomy is planned, additional embolization of segment 4 provides volume hypertrophy similar to that in patients undergoing single-stage hepatectomy.

Use of Pharmacologic Agents for Modulation of Ischaemia-Reperfusion Injury after Hepatectomy: A Questionnaire Study of the LiverMetSurvey International Registry of Hepatic Surgery Units

Objectives. This study is a questionnaire survey on the use of pharmacological agents to modify liver ischaemia-reperfusion (IR) injury in patients undergoing hepatectomy for colorectal liver metastases with the target population being those units participating in the LiverMetSurvey international registry. Methods. Members of LiverMetSurvey were sent an online questionnaire using SurveyMonkey comprising ten questions on the use of pharmacological agents to modulate hepatic IR injury in the perioperative period after hepatectomy. The questionnaire was sent to 446 clinicians registered with the LiverMetSurvey. There were 83 (19%) respondents. Results. Fifty-two (77% of 68 respondents to this question) never used pharmacological agents to modify liver IR injury during hepatectomy. Thirteen (19%) used pharmacological agents selectively. Three (4%) used these routinely. N-Acetylcysteine was the most widely used pharmacological agent with equal distribution of use around intraoperative and postoperative periods. Conclusions. This is believed to be the first survey on the use of pharmacological agents to modify liver IR injury. The target population is clinicians involved in liver resection. The results show that pharmacological modulation is used by only a minority of respondents to this questionnaire and that when this treatment is selected, N-acetylcysteine is the most frequently used.

Staged liver resection for perihilar liver tumors using a tourniquet in the umbilical fissure and sequential portal vein embolization on the fourth postoperative day (a modified ALTPS)

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) achieves the hypertrophy of the future liver remnant in seven days. We achieved the same hypertrophy placing a tourniquet in the parenchimal transection line associating a right portal vein ligation (associating liver tourniquet and right portal vein ligation for staged hepatectomy-ALTPS). In perihiliar tumors a«non touch» technique should be performed. ALPPS y ALTPS do not comply with this technical aspect because a dissection of the hilum is carried out in both procedures during the portal dissection. To avoid this problem we devised a new method called sequential ALTPS. It consists of placing a tourniquet in the umbilical fissure without ligation of the right portal vein during the first stage. Subsequently, on the 4(th) postoperative day we perform a percutaneous right portal vein embolization. We present the first case of this new technique in which we have obtained a hypertrophy of 77% of the future liver remnant seven days after portal vein embolization. In the second stage a right trisectionectomy was performed with inferior vena cava resection with a goretex graft replacement.

Tourniquet modification of the associating liver partition and portal ligation for staged hepatectomy procedure

BACKGROUND

In staged liver resections, associating liver partition and portal ligation for staged hepatectomy (ALPPS) achieves sufficient hypertrophy of the future liver remnant (FLR) in 7 days. This is based on portal vein ligation and transection, and on occlusion of intrahepatic collaterals. This article presents a new surgical technique for achieving rapid hypertrophy of the FLR, which also involves adding intrahepatic collateral occlusion to portal vein transection.

METHODS

Patients scheduled for two-stage liver resection for primary or secondary liver tumours, in whom the FLR was considered too small, were enrolled prospectively. In the first stage, a tourniquet was placed around the parenchymal transection line, and the right portal vein was ligated and cut (associating liver tourniquet and portal ligation for staged hepatectomy, ALTPS). The tourniquet was placed on the umbilical ligament if a staged right trisectionectomy was planned, and on Cantlie's line for staged right hepatectomy.

RESULTS

From September 2011, 22 ALTPS procedures were carried out (right trisectionectomy in 15, right hepatectomy in 7). Median FLR at 7 days increased from 410 to 700 ml (median increase 61 (range 33-189) per cent). The median duration of the first stage was 125 min and no patient received a blood transfusion. The median duration of the second stage was 150 min and five patients required a blood transfusion. Fourteen patients had complications, most frequently infected collections, and five patients developed postoperative liver failure. Two patients died.

CONCLUSION

The ALTPS technique achieved adequate hypertrophy of the FLR after 7 days. It may provide a less aggressive modification of the ALPPS procedure.

Improved hypertrophy of future remnant liver after portal vein embolization with plugs, coils and particles

PURPOSE

To retrospectively analyze efficacy as measured by volume gain of future remnant liver (FRL) after right portal vein embolization (PVE) using particles only versus particles and additional central plug and/or coil (CP/C) embolization.

METHODS

All patients who underwent PVE between July 2011 and December 2012 were retrospectively analyzed. Right PVE was performed either with particle-only (PO) embolization or additional CP/C embolization. All enrolled patients underwent computed tomography or magnetic resonance imaging before PVE and surgery. The images were used for volumetry of the FRL.

RESULTS

Of 75 patients, 40 had PO and 35 CP/C embolization. Age, sex, and tumor entities did not differ significantly between the two groups. Tumor entities included cholangiocarcinoma (n = 52), metastasis from colorectal cancer (n = 14), hepatocellular carcinoma (n = 2), and others (n = 7). Time from PVE to preoperative imaging was similar in both groups. FRL volume before PVE was 329 ± 121 ml in the PO group and 333 ± 135 ml in the CP/C group, and 419 ± 135 ml and 492 ± 165 ml before operation. The average percentage volume gain was significantly higher in the CP/C group than in the PO group, with 53.3 ± 34.5 % versus 30.9 ± 28.8 % (p = 0.002).

CONCLUSION

Right PVE with additional CP/C embolization leads to a significantly higher gain in FRL volume than embolization with particles alone.

Right portal vein embolization by laparoscopic catheterization of the inferior mesenteric vein

Right portal vein embolization is often performed to prevent liver insufficiency after major hepatic resection. The procedure usually involves direct puncture of the portal vein, which requires hepatic hilum manipulation, and may be associated with liver injury, pneumothorax, and hemoperitoneum. This report describes a technique of laparoscopic insertion of a sheath into the inferior mesenteric vein followed by right portal vein embolization.

Liver angulometry: a simple method to estimate liver volume and ratios

OBJECTIVES

Volumetry is standard method for evaluating the volumes of the right liver (RL), left liver (LL), left lateral segments (LLS), total liver (TL) and future liver remnant (FLR). The aim of this study was to report a simple technique based on measurements of liver angles (angulometry) that can be used to predict liver ratios.

METHODS

Fifty computed tomography (CT) scans obtained in subjects with normal liver were studied. Four CT scan levels were preselected: level 1 passed by the upper part of the hepatic veins; level 2 passed by the left portal vein branch division; level 3 passed by the right portal vein branch division, and level 4 passed by the gallbladder bed. Left and right tangent lines passing the liver edges were drawn and joined to the centre of the vertebra defining the TL angle. Two lines through, respectively, the plane of the middle hepatic vein and the left portal branches determined the angles of the RL, LL and LLS. Volumetric and angulometric data obtained on levels 2 and 3 in 50 different subjects were compared.

RESULTS

Level 2 CT scans represented the most accurate way of obtaining angulometric measurements. The mean ± standard deviation (SD) angles of the TL and LL were 134 ± 12 ° and 55 ± 12 °, respectively. The mean ± SD percentages of the TL represented by the LL in angulometry and volumetry were 38 ± 7% and 36 ± 6%, respectively (non-significant difference). The mean ± SD percentages of the TL represented by the LLS in angulometry and volumetry were 25 ± 4% and 20 ± 3%, respectively (P < 0.05). The mean ± SD overestimation of the percentage of the TL represented by the LLS in angulometry was 2.7 ± 7.0%.

CONCLUSIONS

Angulometry is a simple and accurate technique that can be used to estimate the ratio of the FLR to TL volume on one or two CT (or magnetic resonance imaging) slices. It can be helpful for clinicians, especially before right or extended right hepatectomy and after right portal vein occlusion techniques.

Update on portal vein embolization: evidence-based outcomes, controversies, and novel strategies

Portal vein embolization (PVE) is an established therapy used to redirect portal blood flow away from the tumor-bearing liver to the anticipated future liver remnant (FLR) and usually results in FLR hypertrophy. PVE is indicated when the FLR is considered too small before surgery to support essential function after surgery. When appropriately applied, PVE reduces postoperative morbidity and increases the number of patients eligible for curative hepatic resection. PVE also has been combined with other therapies to improve patient outcomes. This article assesses more recent outcomes data regarding PVE, reviews the existing controversies, and reports on novel strategies currently being investigated.