Avoiding postoperative mortality after ALPPS-development of a tumor-specific risk score for colorectal liver metastases

Clinical Prediction Models for Prognosis of Colorectal Liver Metastases: A Comprehensive Review of Regression-Based and Machine Learning Models

Colorectal liver metastasis (CRLM) is a disease entity that warrants special attention due to its high frequency and potential curability. Identification of "high-risk" patients is increasingly popular for risk stratification and personalization of the management pathway. Traditional regression-based methods have been used to derive prediction models for these patients, and lately, focus has shifted to artificial intelligence-based models, with employment of variable supervised and unsupervised techniques. Multiple endpoints, like overall survival (OS), disease-free survival (DFS) and development or recurrence of postoperative complications have all been used as outcomes in these studies. This review provides an extensive overview of available clinical prediction models focusing on the prognosis of CRLM and highlights the different predictor types incorporated in each model. An overview of the modelling strategies and the outcomes chosen is provided. Specific patient and treatment characteristics included in the models are discussed in detail. Model development and validation methods are presented and critically appraised, and model performance is assessed within a proposed framework.

The value of intraoperative dynamic liver function test ICG in predicting postoperative complications in patients undergoing staged hepatectomy: a pilot study

PURPOSE

To assess the predictive value of intraoperative indocyanine green (ICG) test in patients undergoing staged hepatectomy.

METHODS

We analyzed intraoperative ICG measurements of future liver remnant (FLR), preoperative ICG, volumetry, and hepatobiliary scintigraphy in 15 patients undergoing associated liver partition and portal vein ligation for staged hepatectomy (ALPPS). Main endpoints were the correlation of intraoperative ICG values to postoperative complications (Comprehensive Complication Index (CCI®)) at discharge and 90 days after surgery, and to postoperative liver function.

RESULTS

Median intraoperative R15 (ICG retention rate at 15 min) correlated significantly with CCI® at discharge (p = 0.05) and with CCI® at 90 days (p = 0.0036). Preoperative ICG, volumetry, and scintigraphy did not correlate to postoperative outcome. ROC curve analysis revealed a cutoff value of 11.4 for the intraoperative R15 to predict major complications (Clavien-Dindo ≥ III) with 100% sensitivity and 63% specificity. No patient with R15 ≤ 11 developed major complications.

CONCLUSION

This pilot study suggests that intraoperative ICG clearance determines the functional capacity of the future liver remnant more accurately than preoperative tests. This may further reduce the number of postoperative liver failures, even if it means intraoperative abortion of hepatectomy in individual cases.

A bibliometric and visualized analysis of preoperative future liver remnant augmentation techniques from 1997 to 2022

Background

The size and function of the future liver remnant (FLR) is an essential consideration for both eligibility for treatment and postoperative prognosis when planning surgical hepatectomy. Over time, a variety of preoperative FLR augmentation techniques have been investigated, from the earliest portal vein embolization (PVE) to the more recent Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) and liver venous deprivation (LVD) procedures. Despite numerous publications on this topic, no bibliometric analysis has yet been conducted.

Methods

Web of Science Core Collection (WoSCC) database was searched to identify studies related to preoperative FLR augmentation techniques published from 1997 to 2022. The analysis was performed using the CiteSpace [version 6.1.R6 (64-bit)] and VOSviewer [version 1.6.19].

Results

A total of 973 academic studies were published by 4431 authors from 920 institutions in 51 countries/regions. The University of Zurich was the most published institution while Japan was the most productive country. Eduardo de Santibanes had the most published articles, and Masato Nagino was the most frequently co-cited author. The most frequently published journal was HPB, and the most cited journal was Ann Surg, with 8088 citations. The main aspects of preoperative FLR augmentation technique is to enhance surgical technology, expand clinical indications, prevent and treat postoperative complications, ensure long-term survival, and evaluate the growth rate of FLR. Recently, hot keywords in this field include ALPPS, LVD, and Hepatobiliary Scintigraphy.

Conclusion

This bibliometric analysis provides a comprehensive overview of preoperative FLR augmentation techniques, offering valuable insights and ideas for scholars in this field.

Liver growth prediction in ALPPS - A multicenter analysis from the international ALPPS registry

BACKGROUND

While ALPPS triggers a fast liver hypertrophy, it is still unclear which factors matter most to achieve accelerated hypertrophy within a short period of time. The aim of the study was to identify patient-intrinsic factors related to the growth of the future liver remnant (FLR).

METHODS

This cohort study is composed of data derived from the International ALPPS Registry from November 2011 and October 2018. We analyse the influence of demographic, tumour type and perioperative data on the growth of the FLR. The volume of the FLR was calculated in millilitre and percentage using computed-tomography (CT) scans before and after stage 1, both according to Vauthey formula.

RESULTS

A total of 734 patients were included from 99 centres. The median sFLR at stage 1 and stage 2 was 0.23 (IQR, 0.18-0.28) and 0.39 (IQR: 0.31-0.46), respectively. The variables associated with a lower increase from sFLR1 to sFLR2 were age˃68 years (p = .02), height ˃1.76 m (p ˂ .01), weight ˃83 kg (p ˂ .01), BMI˃28 (p ˂ .01), male gender (p ˂ .01), antihypertensive therapy (p ˂ .01), operation time ˃370 minutes (p ˂ .01) and hospital stay˃14 days (p ˂ .01). The time required to reach sufficient volume for stage 2, male gender accounts 40.3% in group ˂7 days, compared with 50% of female, and female present 15.3% in group ˃14 days compared with 20.6% of male.

CONCLUSIONS

Height, weight, FLR size and gender could be the variables that most constantly influence both daily growths, the interstage increase and the standardized FLR before the second stage.

Current evidence on posthepatectomy liver failure: comprehensive review

INTRODUCTION

Despite important advances in many areas of hepatobiliary surgical practice during the past decades, posthepatectomy liver failure (PHLF) still represents an important clinical challenge for the hepatobiliary surgeon. The aim of this review is to present the current body of evidence regarding different aspects of PHLF.

METHODS

A literature review was conducted to identify relevant articles for each topic of PHLF covered in this review. The literature search was performed using Medical Subject Heading terms on PubMed for articles on PHLF in English until May 2022.

RESULTS

Uniform reporting on PHLF is lacking due to the use of various definitions in the literature. There is no consensus on optimal preoperative assessment before major hepatectomy to avoid PHLF, although many try to estimate future liver remnant function. Once PHLF occurs, there is still no effective treatment, except liver transplantation, where the reported experience is limited.

DISCUSSION

Strict adherence to one definition is advised when reporting data on PHLF. The use of the International Study Group of Liver Surgery criteria of PHLF is recommended. There is still no widespread established method for future liver remnant function assessment. Liver transplantation is currently the only effective way to treat severe, intractable PHLF, but for many indications, this treatment is not available in most countries.

The use of neoadjuvant lobar radioembolization prior to major hepatic resection for malignancy results in a low rate of post hepatectomy liver failure

Background

Neoadjuvant yttrium-90 transarterial radioembolization (TARE) is increasingly being used as a strategy to facilitate resection of otherwise unresectable tumors due to its ability to generate both tumor response and remnant liver hypertrophy. Perioperative outcomes after the use of neoadjuvant lobar TARE remain underinvestigated.

Methods

A single center retrospective review of patients who underwent lobar TARE prior to major hepatectomy for primary or metastatic liver cancer between 2007 and 2018 was conducted. Baseline demographics, radioembolization parameters, pre- and post-radioembolization volumetrics, intra-operative surgical data, adverse events, and post-operative outcomes were analyzed.

Results

Twenty-six patients underwent major hepatectomy after neoadjuvant lobar TARE. The mean age was 58.3 years (17-88 years). 62% of patients (n=16) had primary liver malignancies while the remainder had metastatic disease. Liver resection included right hepatectomy or trisegmentectomy, left or extended left hepatectomy, and sectorectomy/segmentectomy in 77% (n=20), 8% (n=2), and 15% (n=4) of patients, respectively. The mean length of stay was 8.3 days (range, 3-33 days) and there were no grade IV morbidities or 90-day mortalities. The incidence of post hepatectomy liver failure (PHLF) was 3.8% (n=1). The median time to progression after resection was 4.5 months (range, 3.3-10 months). Twenty-three percent (n=6) of patients had no recurrence. The median survival was 28.9 months (range, 16.9-46.8 months) from major hepatectomy and 37.6 months (range, 25.2-53.1 months) from TARE.

Conclusions

Major hepatectomy after neoadjuvant lobar radioembolization is safe with a low incidence of PHLF.

Uncommon indications for associating liver partition and portal vein ligation for staged hepatectomy: a systematic review

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) represents an innovative surgical technique used for the treatment of large hepatic lesions at high risk for post-resection liver failure due to a small future liver remnant. The most significant amount of literature concerns the use of ALPPS for the treatment of hepatocellular carcinoma (HCC), cholangiocarcinoma (CCC), and colorectal liver metastases (CRLM). On the opposite, few is known about the role of ALPPS for the treatment of uncommon liver pathologies. The objective of the present study was to evaluate the current literature on this topic. A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Eligible articles published up to February 2020 were included using the MEDLINE, Scopus, and Cochrane databases. Among the 486 articles screened, 45 papers met the inclusion criteria, with 136 described cases of ALPPS for rare indications. These 136 cases were reported in 18 different countries. Only in two countries, namely Germany and Brazil, more than ten cases were observed. As for the ALPPS indications, we reported 41 (30.1%) cases of neuroendocrine tumor (NET) metastases, followed by 27 (19.9%) cases of gallbladder cancer (GBC), nine (6.6%) pediatric cases, six (4.4%) gastrointestinal stromal tumors, six (4.4%) adult cases of benign primary liver disease, four (2.9%) adult cases of malignant primary liver disease, and 43 (31.6%) adult cases of malignant secondary liver disease. According to the International ALPPS Registry data, less than 10% of the ALPPS procedures have been performed for the treatment of uncommon liver pathologies. NET and GBC are the unique pathologies with acceptable numerosity. ALPPS for NET appears to be a safe procedure, with satisfactory long-term results. On the opposite, the results observed for the treatment of GBC are poor. However, these data should be considered with caution. The rationale for treating benign pathologies with ALPPS appears to be weak. No definitive response should be given for all the other pathologies. Multicenter studies are needed with the intent to clarify the potentially beneficial effect of ALPPS for their treatment.

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.

The role of associating liver partition and portal vein ligation for staged hepatectomy in the management of patients with colorectal liver metastasis

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) approach emerged as a promising surgical strategy for rapid and large hypertrophy of the future liver remnant (FLR) when a major liver resection is necessary. Colorectal liver metastasis (CRLM) is their main indication. However, the promising results published so far, are very difficult to interpret since they usually focus on the technique and not on the underlying disease. Moreover, they are usually made up of complex populations, which received different chemotherapy schemes, with the ALPPS technical variations implemented over time and without consistent long-term follow-up results as well. Whereby, its role in CRLM should be analyzed as carefully as possible to indicate and select the best candidates who will benefit the most from this approach. We conducted a computerized search using PubMed and Google Scholar for reports published so far, using mesh headings and keywords related to the ALPPS and CRLM.

Renal Impairment Is Associated with Reduced Outcome After Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy

BACKGROUND

Impaired postoperative renal function is associated with increased morbidity and mortality after liver resection. The role of impaired renal function in the two-stage hepatectomy setting of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is unknown.

METHODS

An international multicenter cohort of ALPPS patients captured in the ALPPS Registry was analyzed. Particular attention was drawn to the renal function in the interstage interval to determine outcome after stage 2 surgery. Interstage renal impairment (RI) was defined as an increase of serum creatinine of ≥ 0.3 mg/dl referring to a preoperative value or an increase of serum creatinine of ≥ 1.5× of the preoperative value on the fifth postoperative day after stage 1.

RESULTS

A total of 705 patients were identified of which 7.5% had an interstage RI. Patients developing an interstage RI were significantly older. During stage 1, a longer operation time, higher rate of intraoperative transfusions, and additional procedures were observed in patients that developed interstage RI. After stage 1, interstage RI patients had more major complications and higher interstage mortality (1% vs. 8%, p < 0.001). Furthermore, these patients developed more and severe complications after completion of stage 2. Mortality of patients with interstage RI was 38% vs. 8% without interstage RI. In 41% of patients with interstage RI, the renal function recovered before stage 2; however, the mortality after stage 2 remained 28% in those patients. Risk factors for the development of an interstage RI were age over 67 years, prolonged operative time, and additional procedure during stage 1.

CONCLUSION

This study shows that interstage RI is a predictor for interstage and post-stage 2 morbidity and perioperative mortality. The causality of impaired renal function on outcome, however, remains unknown. Interstage RI may directly cause adverse outcome but may also be a surrogate marker for major complications.

Hepatobiliary scintigraphy and kinetic growth rate predict liver failure after ALPPS: a multi-institutional study

BACKGROUND

Post hepatectomy liver failure (PHLF) after ALPPS has been related to the discrepancy between liver volume and function. Pre-operative hepatobiliary scintigraphy (HBS) can predict post-operative liver function and guide when it is safe to proceed with major hepatectomy. Aim of this study was to evaluate the role of HBS in predicting PHLF after ALPPS, defining a safe cut-off.

METHODS

A multicenter retrospective study was approved by the ALPPS Registry. All patients selected for ALPPS between 2012 and 2018, were evaluated. Every patient underwent HBS during ALPPS evaluation. PHLF was reported according to ISGLS definition, considering grade B or C as clinically significant.

RESULTS

98 patients were included. Thirteen patients experienced PHLF grade B or C (14%) following ALPPS-2. The HBS and the daily gain in volume (KGR_FLR) of the future liver remnant (FLR) were significantly lower in PHLF B and C (p = .004 and .041 respectively). ROC curves indicated safe cut-offs of 4.1%/day (AUC = 0.68) for KGR_FLR, and of 2.7 %/min/m² (AUC = 0.75) for HBS_FLR. Multivariate analysis confirmed these cut-offs as variables predicting PHLF after ALPPS-2.

CONCLUSION

Patients presenting a KGR_FLR ≤4.1%/day and a HBS_FLR ≤2.7%/min/m² are at high risk of PHLF and their second stage should be re-discussed.

Conventional Two-Stage Hepatectomy or Associating Liver Partitioning and Portal Vein Ligation for Staged Hepatectomy for Colorectal Liver Metastases? A Systematic Review and Meta-Analysis

Background: Pushing the surgical limits for initially unresectable colorectal liver metastases (CRLM) are two approaches for sequential liver resection: two-stage hepatectomy (TSH) and associating liver partitioning and portal vein ligation for staged hepatectomy (ALPPS). However, the role of each treatment modality remains ill-defined. The present meta-analysis was designed to compare the safety, efficacy, and oncological benefits between ALPPS and TSH in the management of advanced CRLM.

Methods: A systematic literature search was conducted from online databases through to February 2020. Single-arm synthesis and cumulative meta-analysis were performed.

Results: Eight studies were included, providing a total of 409 subjects for analysis (ALPPS: N = 161; TSH: N = 248). The completions of the second stage of the hepatectomy [98 vs. 78%, odds ratio (OR) 5.75, p < 0.001] and R0 resection (66 vs. 37%; OR 4.68; p < 0.001) were more frequent in patients receiving ALPPS than in those receiving TSH, and the waiting interval was dramatically shortened in ALPPS (11.6 vs. 45.7 days, weighted mean difference = −35.3 days, p < 0.001). Nevertheless, the rate of minor complications was significantly higher in ALPPS (59 vs. 18%, OR 6.5, p < 0.001) than in TSH. The two treatments were similar in 90-day mortality (7 vs. 5%, p = 0.43), major complications (29 vs. 22%, p = 0.08), posthepatectomy liver failure (PHLF; 9 vs. 9%, p = 0.3), biliary leakage (11 vs. 14%, p = 0.86), length of hospital stay (27.95 vs. 26.88 days, p = 0.8), 1-year overall survival (79 vs. 84%, p = 0.61), 1-year recurrence (49 vs. 39%, p = 0.32), and 1-year disease-free survival (34 vs. 39%, p = 0.66). Cumulative meta-analyses indicated chronological stability for the pooled effect sizes of resection rate, 90-day mortality, major complications, and PHLF.

Conclusions: Compared with TSH, ALPPS for advanced CRLM resulted in superior surgical efficacy with comparable perioperative mortality rate and short-term oncological outcomes, while this was at the cost of increased perioperative minor complications.

Improving the Safety of Major Resection for Hepatobiliary Malignancy: Portal Vein Embolization and Recent Innovations in Liver Regeneration Strategies

PURPOSE OF REVIEW

For three decades, portal vein embolization (PVE) has been the "gold-standard" strategy to hypertrophy the anticipated future liver remnant (FLR) in advance of major hepatectomy. During this time, CT volumetry was the most common method to preoperatively assess FLR quality and function and used to determine which patients are appropriate surgical candidates. This review provides the most up-to-date methods for preoperatively assessing the anticipated FLR and summarizes data from the currently available strategies used to induce FLR hypertrophy before surgery for hepatobiliary malignancy.

RECENT FINDINGS

Functional and physiological imaging is increasingly replacing standard CT volumetry as the method of choice for preoperative FLR assessment. PVE, associating liver partition and portal vein ligation, radiation lobectomy, and liver venous deprivation are all currently available techniques to hypertrophy the FLR. Each strategy has pros and cons based on tumor type, extent of resection, presence or absence of underlying liver disease, age, performance status, complication rates, and other factors. Numerous strategies can lead to FLR hypertrophy and improve the safety of major hepatectomy. Which is best has yet to be determined.

Defining Benchmark Outcomes for ALPPS

OBJECTIVE

The aim of this study was to use the concept of benchmarking to establish robust and standardized outcome references after the procedure ALPPS (Associating Liver Partition and Portal Vein Ligation for Staged hepatectomy).

BACKGROUND AND AIMS

The recently developed ALPPS procedure, aiming at removing primarily unresectable liver tumors, has been criticized for safety issues with high variations in the reported morbidity/mortality rates depending on patient, disease, technical characteristics, and center experience. No reference values for relevant outcome parameters are available.

METHODS

Among 1036 patients registered in the international ALPPS registry, 120 (12%) were benchmark cases fulfilling 4 criteria: patients ≤67 years of age, with colorectal metastases, without simultaneous abdominal procedures, and centers having performed ≥30 cases. Benchmark values, defined as the 75th percentile of the median outcome parameters of the centers, were established for 10 clinically relevant domains.

RESULTS

The benchmark values were completion of stage 2: ≥96%, postoperative liver failure (ISGLS-criteria) after stage 2: ≤5%, ICU stay after ALPPS stages 1 and 2: ≤1 and ≤2 days, respectively, interstage interval: ≤16 days, hospital stay after ALPPS stage 2: ≤10 days, rates of overall morbidity in combining both stage 1 and 2: ≤65% and for major complications (grade ≥3a): ≤38%, 90-day comprehensive complication index was ≤22, the 30-, 90-day, and 6-month mortality was ≤4%, ≤5%, and 6%, respectively, the overall 1-year, recurrence-free, liver-tumor-free, and extrahepatic disease-free survival was ≥86%, ≥50%, ≥57%, and ≥65%, respectively.

CONCLUSIONS

This benchmark analysis sets key reference values for ALPPS, indicating similar outcome as other types of major hepatectomies. Benchmark cutoffs offer valid tools not only for comparisons with other procedures, but also to assess higher risk groups of patients or different indications than colorectal metastases.

How to increase the resectability of initially unresectable colorectal liver metastases: A surgical perspective

Although surgical resection is the only treatment of choice that can offer prolonged survival and a chance of cure in patients with colorectal liver metastases (CRLM), nearly 80% of patients are deemed to be unresectable at the time of diagnosis. Considerable efforts have been made to overcome this initial unresectability, including expanding the indication of surgery, the advent of conversion chemotherapy, and development and modification of specific surgical techniques, regulated under multidisciplinary approaches. In terms of specific surgical techniques, portal vein ligation/embolization can increase the volume of future liver remnant and thereby reduce the risk of hepatic insufficiency and death after major hepatectomy. For multiple bilobar CRLM that were traditionally considered unresectable even with preoperative chemotherapy and portal vein embolization, two-stage hepatectomy was introduced and has been adopted worldwide with acceptable short- and long-term outcomes. Recently, ALPPS (associating liver partition and portal vein ligation for staged hepatectomy) was reported as a novel variant of two-stage hepatectomy. Although issues regarding safety remain unresolved, rapid future liver remnant hypertrophy and subsequent shorter intervals between the two stages lead to a higher feasibility rate, reaching 98%. In addition, adding radiofrequency ablation and vascular resection and reconstruction techniques can allow expansion of the pool of patients with CRLM who are candidates for liver resection and thus a cure. In this review, we discuss specific techniques that may expand the criteria for resectability in patients with initially unresectable CRLM.

Dealing with insufficient liver remnant: Associating liver partition and portal vein ligation for staged hepatectomy

Liver resection for colorectal liver metastases has emerged to highly successful treatment in the last decades. Key to this success is complete hepatic tumor removal and systemic disease control by chemotherapy. Associating liver partition and portal vein ligation for staged hepatectomy is the most recent two-stage resection strategy for patients with very small future liver remnant making complete tumor removal possible within 1 to 2 weeks. Oncological outcome data are being collected at the moment and first results from small series reveal promising results.