Current position of ALPPS in the surgical landscape of CRLM treatment proposals

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

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

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.

Role of associating liver partition and portal vein ligation in staged hepatectomy (ALPPS)-strategy for colorectal liver metastases

Colorectal carcinoma (CRC) is the third leading cause of cancer-related death in the United States. The liver is the most frequent site of metastasis and a key determinant of survival in patients with isolated colorectal liver metastasis (CRLM). Surgical resection remains the only hope for prolonged survival in patients with CRLM. However, most patients are deemed to be unresectable at presentation due to a small future liver remnant (FLR) and fear of post-hepatectomy liver failure. Procedures such as portal vein ligation or embolization (PVL/PVE) followed by hepatectomy have been established as standard methods to increase FLR volume, but have limitations dependent upon extent of disease and patient's ability to grow the liver remnant. Recently, associating liver partition and portal vein ligation in staged hepatectomy (ALPPS) has been introduced as a technique to induce liver hypertrophy over a shorter time period. Being a complex two-stage surgical procedure, initial reports of higher ALPPS-associated complications and mortality limited its worldwide adoption by hepatobiliary surgeons. However, recent studies have showed ALPPS superiority over conventional procedures in terms of feasibility and inducing liver hypertrophy, with comparable morbidity and mortality. We herein review the role of ALPPS in management of patients with CRLM.

JNK1 induces hedgehog signaling from stellate cells to accelerate liver regeneration in mice

BACKGROUND & AIMS

To improve outcomes of two-staged hepatectomies for large/multiple liver tumors, portal vein ligation (PVL) has been combined with parenchymal transection (associating liver partition and portal vein ligation for staged hepatectomy [coined ALPPS]) to greatly accelerate liver regeneration. In a novel ALPPS mouse model, we have reported paracrine Indian hedgehog (IHH) signaling from stellate cells as an early contributor to augmented regeneration. Here, we sought to identify upstream regulators of IHH.

METHODS

ALPPS in mice was compared against PVL and additional control surgeries. Potential IHH regulators were identified through in silico mining of transcriptomic data. c-Jun N-terminal kinase (JNK1 [Mapk8]) activity was reduced through SP600125 to evaluate its effects on IHH signaling. Recombinant IHH was injected after JNK1 diminution to substantiate their relationship during accelerated liver regeneration.

RESULTS

Transcriptomic analysis linked Ihh to Mapk8. JNK1 upregulation after ALPPS was validated and preceded the IHH peak. On immunofluorescence, JNK1 and IHH co-localized in alpha-smooth muscle actin-positive non-parenchymal cells. Inhibition of JNK1 prior to ALPPS surgery reduced liver weight gain to PVL levels and was accompanied by downregulation of hepatocellular proliferation and the IHH-GLI1-CCND1 axis. In JNK1-inhibited mice, recombinant IHH restored ALPPS-like acceleration of regeneration and re-elevated JNK1 activity, suggesting the presence of a positive IHH-JNK1 feedback loop.

CONCLUSIONS

JNK1-mediated induction of IHH paracrine signaling from hepatic stellate cells is essential for accelerated regeneration of parenchymal mass. The JNK1-IHH axis is a mechanism unique to ALPPS surgery and may point to therapeutic alternatives for patients with insufficient regenerative capacity.

LAY SUMMARY

Associating liver partition and portal vein ligation for staged hepatectomy (so called ALPPS), is a new two-staged approach to hepatectomy, which induces an unprecedented acceleration of liver regeneration, enabling treatment of patients with liver tumors that would otherwise be considered unresectable. Herein, we demonstrate that JNK1-IHH signaling from stellate cells is a key mechanism underlying the regenerative acceleration that is induced by ALPPS.

Insight on ALPPS - Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy - mechanisms: activation of mTOR pathway

BACKGROUND

ALPPS procedure has been introduced to increase the volume of future liver remnant. The mechanisms underlying the accelerated regeneration observed with ALPPS are unknown. It was hypothesized that AMPK/mTOR is activated as an integrating pathway for metabolic signals leading to proliferation and cell growth. Our aim was to analyze increase in liver volume, proliferation parameters and expression of AMPK/mTOR pathway-related molecules in patients undergoing ALPPS.

METHODS

A single center prospective study of patients undergoing ALPPS was performed from 2013 to 2015. Liver and serum samples, clinical laboratory results and CT-scan data were obtained. ELISA, Ki-67 immunostaining and qRT-PCR were performed in deportalized and remnant liver tissue in both stages of the procedure.

RESULTS

11 patients were enrolled. Remnant liver volume increased 112 ± 63% (p < 0.05) in 9.1 ± 1.6 days. Proliferation-related cytokines IL-6, TNF-α, HGF and EGF significantly increased, while higher Ki-67 immunostaining and cyclin D expression were observed in remnant livers after ALPPS. mTOR, S6K1, 4E-BP1, TSC1 and TSC2 expression were significantly increased in remnant livers at second stage, while AMPK and Akt increased only in deportalized liver samples.

CONCLUSION

Rapid liver regeneration with ALPPS might be associated with hepatocyte proliferation induced by mTOR pathway activation.

Combined associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) followed by left trisectionectomy and Whipple operation for PNET

Pancreatic neuroendocrine tumor (PNET) is slow-growing, and account only for 2% of all pancreatic primary tumors. Surgical resection is still the only curative treatment for PNET patients. Unfortunately, most of PNETs was found with unresectable multiple liver metastases and extrahepatic metastasis as their characteristics of non-functional and asymptomatic. With advances in liver surgery in these years, especially combined associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), provide a new curative surgical treatment for PNET with liver metastases patient. Here we report a PNET with multiple liver metastases case underwent ALPPS (followed by left trisectionectomy) and Whipple operation within one-stage.

The Safety and Feasibility of Three-Dimensional Visualization Technology Assisted Right Posterior Lobe Allied with Part of V and VIII Sectionectomy for Right Hepatic Malignancy Therapy

BACKGROUND

Hepatectomy is the optimal method for liver cancer; the virtual liver resection based on three-dimensional visualization technology (3-DVT) could provide better preoperative strategy for surgeon. We aim to introduce right posterior lobe allied with part of V and VIII sectionectomy assisted by 3-DVT as a promising treatment for massive or multiple right hepatic malignancies to retain maximum residual liver volume on the basis of R0 resection.

METHODS

Among 126 consecutive patients who underwent hepatectomy, 9 (7%) underwent right posterior lobe allied with part of V and VIII sectionectomy. 21 (17%) underwent right hemihepatectomy (RH). The virtual RH was performed with 3-DVT, which provided better observation of spatial position relationship between tumor and vessels, and the more accurate estimation of the remnant liver volume. If remnant liver volume was <40%, right posterior lobe allied with part of V and VIII sectionectomy should be undergone. Then, the precut line ought to be planned on the basis of protecting the portal branch of subsegment 5 and 8. The postoperative outcome of patients was compared before and after propensity score matching.

RESULTS

Nine patients meeting the eligibility criteria received right posterior lobe allied with part of V and VIII sectionectomy. The variables, including the overall mean operation time, blood transfusion, operation length, liver function, and postoperative complications, were similar between two groups before and after propensity matching. The postoperative first, third, fifth, and seventh days mean value of aspartate aminotransferase (AST), alanine aminotransferase (ALT), albumin (ALB), and total bilirubin had no significant difference compared with preoperative value. One patient in each group had recurrence six months after surgery.

CONCLUSION

Right posterior lobe allied with part of V and VIII sectionectomy based on 3-DVT is safe and feasible surgery way, and can be a very promising method in massive or multiple right hepatic malignancy therapy.

Extreme liver resections with preservation of segment 4 only

AIM

To evaluate safety and outcomes of a new technique for extreme hepatic resections with preservation of segment 4 only.

METHODS

The new method of extreme liver resection consists of a two-stage hepatectomy. The first stage involves a right hepatectomy with middle hepatic vein preservation and induction of left lobe congestion; the second stage involves a left lobectomy. Thus, the remnant liver is represented by the segment 4 only (with or without segment 1, ± S1). Five patients underwent the new two-stage hepatectomy (congestion group). Data from volumetric assessment made before the second stage was compared with that of 10 matched patients (comparison group) that underwent a single-stage right hepatectomy with middle hepatic vein preservation.

RESULTS

The two stages of the procedure were successfully carried out on all 5 patients. For the congestion group, the overall volume of the left hemiliver had increased 103% (mean increase from 438 mL to 890 mL) at 4 wk after the first stage of the procedure. Hypertrophy of the future liver remnant (i.e., segment 4 ± S1) was higher than that of segments 2 and 3 (144% vs 54%, respectively, P < 0.05). The median remnant liver volume-to-body weight ratio was 0.3 (range, 0.28-0.40) before the first stage and 0.8 (range, 0.45-0.97) before the second stage. For the comparison group, the rate of hypertrophy of the left liver after right hepatectomy with middle hepatic vein preservation was 116% ± 34%. Hypertrophy rates of segments 2 and 3 (123% ± 47%) and of segment 4 (108% ± 60%, P > 0.05) were proportional. The mean preoperative volume of segments 2 and 3 was 256 ± 64 cc and increased to 572 ± 257 cc after right hepatectomy. Mean preoperative volume of segment 4 increased from 211 ± 75 cc to 439 ± 180 cc after surgery.

CONCLUSION

The proposed method for extreme hepatectomy with preservation of segment 4 only represents a technique that could allow complete resection of multiple bilateral liver metastases.

Associating liver partition and portal vein ligation for staged hepatectomy: A surgical technique for liver resections

Background:

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a novel surgical technique liver resection in traditionally nonresectable primary intrahepatic tumors or colorectal liver metastases.

Materials and Methods:

From June 2013 to March 2014, patients with primary tumor of liver or colorectal tumors with liver metastasis were selected to evaluate whether they met the initial criteria for ALPPS procedure.

Results:

Nine patients enrolled in the study with primary diagnoses of colon and rectosigmoid cancer, carcinoid tumor, gastrointestinal stromal tumor of small intestine, hepatocellular carcinoma, and pancreatic neuroendocrine tumor (PNET). Four candidates excluded from the study prior or during the first step operation due to fatty liver, hepatic fibrosis, peritoneal seeding, and multiple small intestine metastases. Five patients underwent two stages of ALPPS with the interval of about 1 week. Liver hypertrophy was 100% among our candidates after the initial step. One postoperative death happened because of massive pulmonary thromboembolism Recurrence of liver metastasis was seen in one patient. Hepatic failure Class B and A were observed in two patients which did not progress during follow-up period. One patient developed an enterocutaneous fistula.

Discussion:

We recommend to use 2 organ bags, one for wrapping right lobe and the other one for covering visceral organs and also do liver biopsy in suspicious cases of damaged liver parenchyma and laparoscopic exploration of abdomen for seeding and multiple metastases prior to laparotomy.

Conclusion:

As the procedure has not been well established and verified by oncologists yet, further studies are required to define the exact indications of ALPPS.

Animal Models for Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS): Achievements and Future Perspectives

Background: Since 2012, Associated Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS) has been standing in the limelight of modern liver surgery and numerous questions have been raised regarding this novel approach. On the one hand, ALPPS has proved to be a valuable method in the treatment of hepatic tumors, while on the other hand, there are many controversies, such as high mortality and morbidity rates. Further surgical research is essential for a better understanding of underlying mechanisms and for enhancing patient safety. Summary: Until recently, only 8 animal models have been created with the purpose to mimic ALPPS-induced liver regeneration. From these 7 are rodent (6 rat and 1 mouse) models, while only 1 is a large animal model, which uses pigs. In case of rodent models, portal flow deprivation of 75-90% is achieved via portal vein ligation leaving only the right (20-25%) or left median (10-15%) lobes portally perfused, while liver splitting in general is carried out positioned according to the falciform ligament. As for the swine model, the left lateral and medial lobes (70-75% of total liver volume) are portally ligated, and the right lateral lobe (accounting for 20-24% of the parenchyma) is partially resected in order to reach critical liver volume. Each model is capable of reproducing the accelerated liver regeneration seen in human cases. However, all species have significantly different liver anatomy compared with the human anatomic situation, making clinical translation somewhat difficult. Key Messages: Unfortunately, there are no perfect animal models available for ALPPS research. Small animal models are inexpensive and well suited for basic research, but may only provide limited translational potential to humans. Clinically large animal models may provide more relevant data, but currently no suitable one exists.

Hedgehog pathway mediates early acceleration of liver regeneration induced by a novel two-staged hepatectomy in mice

BACKGROUND & AIMS

ALPPS, a novel two-staged approach for the surgical removal of large/multiple liver tumors, combines portal vein ligation (PVL) with parenchymal transection. This causes acceleration of compensatory liver growth, enabling faster and more extensive tumor removal. We sought to identify the plasma factors thought to mediate the regenerative acceleration following ALPPS.

METHODS

We compared a mouse model of ALPPS against PVL and additional control surgeries (n=6 per group). RNA deep sequencing was performed to identify candidate molecules unique to ALPPS liver (n=3 per group). Recombinant protein and a neutralizing antibody combined with appropriate surgeries were used to explore candidate functions in ALPPS (n=6 per group). Indian hedgehog (IHH/Ihh) levels were assessed in human ALPPS patient plasma (n=6).

RESULTS

ALPPS in mouse confirmed significant acceleration of liver regeneration relative to PVL (p<0.001). Ihh mRNA, coding for a secreted ligand inducing hedgehog signaling, was uniquely upregulated in ALPPS liver (p<0.001). Ihh plasma levels rose 4h after surgery (p<0.01), along with hedgehog pathway activation and subsequent cyclin D1 induction in the liver. When combined with PVL, Ihh alone was sufficient to induce ALPPS-like acceleration of liver growth. Conversely, blocking Ihh markedly inhibited the accelerating effects of ALPPS. In the small cohort of ALPPS patients, IHH tended to be elevated early after surgery.

CONCLUSIONS

Ihh and hedgehog pathway activation provide the first mechanistic insight into the acceleration of liver regeneration triggered by ALPPS surgery. The accelerating potency of recombinant Ihh, and its potential effect in human ALPPS may lead to a clinical role for this protein.

LAY SUMMARY

ALPPS, a novel two-staged hepatectomy, accelerates liver regeneration, thereby helping to treat patients with otherwise unresectable liver tumors. The molecular mechanisms behind this accelerated regeneration are unknown. Here, we elucidate that Indian hedgehog, a secreted ligand important for fetal development, is a crucial mediator of the regenerative acceleration triggered by ALPPS surgery.

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) in colorectal liver metastasis: the radiologist's perspective

PURPOSE

Hepatic resection is the only potentially curative treatment for patients with colorectal liver metastasis (CRLM). Many multidisciplinary approaches, including the associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) procedure, have been proposed to increase the resectability rate in these patients. ALPPS is the most recently described staged liver resection technique, representing an advantageous strategy to induce a rapid and marked increase in the future liver remnant (FLR) volume. The aim of this article is to describe the radiological evaluation of this procedure and its variation.

METHODS

This retrospective study included 9 patients with CRLM who underwent the ALPPS procedure. Abdominal imaging studies were reviewed, with an emphasis on a rational radiological approach. The number of liver metastases, the FLR volume (pre- and postportal vein ligation), anatomical variations, potential pitfalls related to disease progression, and postoperative complications were evaluated.

RESULTS

The types of hepatic resection included 4 classical ALPPS cases, 3 right ALPPS variations, and 2 left ALPPS variations. The mean FLR volume calculated in the initial evaluation was 453 mL (213-790 mL). Following the first surgery, the mean FLR volume increased to 634 mL (410-957 mL), which indicated a mean volume increase of 181.1 mL (95% CI 149.7-212.5 mL; p < 0.001) and a mean absolute volume increase of 48% (19%-88%).

CONCLUSION

The ALPPS procedure is an emerging form of two-stage hepatectomy. In this context, radiologists should provide crucial preoperative and perioperative information that may change surgical planning and contribute to an improvement in the oncologic outcome.

FIRST BRAZILIAN CONSENSUS ON MULTIMODAL TREATMENT OF COLORECTAL LIVER METASTASES. MODULE 1: PRE-TREATMENT EVALUATION

Background

: Liver metastases of colorectal cancer are frequent and potentially fatal event in the evolution of patients with these tumors.

Aim

: In this module, was contextualized the clinical situations and parameterized epidemiological data and results of the various treatment modalities established.

Method:

Was realized deep discussion on detecting and staging metastatic colorectal cancer, as well as employment of imaging methods in the evaluation of response to instituted systemic therapy.

Results

: The next step was based on the definition of which patients would have their metastases considered resectable and how to expand the amount of patients elegible for modalities with curative intent.

Conclusion

: Were presented clinical, pathological and molecular prognostic factors, validated to be taken into account in clinical practice.

The Future Liver Remnant in Patients Undergoing the Associating Liver Partition with Portal Vein Ligation for Staged Hepatectomy (ALPPS) Maintains the Immunological Components of a Healthy Organ

Background and Aims

A short-interval, two-stage approach termed associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) increases the number of patients with extensive malignant disease of the liver and a small future liver remnant (FLR) that can undergo liver resection. While this approach results in accelerated liver hypertrophy of the FLR, it remains unknown whether this phenomenon is restricted to liver parenchymal cells. In the current study, we evaluated whether ALPPS alters the immunological composition of the deportalized lobe (DL) and the FLR.

Methods

In this prospective, single-center study, liver tissue from the DL and the FLR were collected intra-operatively from adult patients undergoing ALPPS for their liver metastases. The extent of hypertrophy of the FLR was determined by volumetric helical computed tomography. Flow cytometry and histological analyses were conducted on liver tissues to compare the frequency of several immune cell subsets, and the architecture of the liver parenchyma between both stages of ALPPS.

Results

A total of 12 patients completed the study. Histologically, we observed a patchy peri-portal infiltration of lymphocytes within the DL, and a significant widening of the liver cords within the FLR. Within the DL, there was a significantly higher proportion of B cells and CD4⁺ T cells as well innate-like lymphocytes, namely mucosa-associated invariant T (MAIT) cells and natural killer T (NKT) cells following ALPPS. In contrast, the frequency of all evaluated immune cell types remained relatively constant in the FLR.

Conclusion

Our results provide the first description of the immunological composition of the human liver following ALPPS. We show that following the ALPPS procedure, while the immune composition of the FLR remains relatively unchanged, there is a moderate increase in several immune cell populations in DL. Overall, our results support the continued utilization of the ALPPS procedure.

Intrahepatic Size Regulation in a Surgical Model: Liver Resection-Induced Liver Regeneration Counteracts the Local Atrophy following Simultaneous Portal Vein Ligation

BACKGROUND/AIM

Liver size regulation is based on the balance between hepatic regeneration and atrophy. To achieve a better understanding of intrahepatic size regulation, we explored the size regulation of a portally deprived liver lobe on a liver subjected to concurrent portal vein ligation (PVL) and partial hepatectomy (PHx).

MATERIALS AND METHODS

Using a surgical rat model consisting of right PVL (rPVL) plus 70% PHx, we evaluated the size regulation of liver lobes 1, 2, 3, and 7 days after the operation in terms of liver weight and hepatocyte proliferation. Portal hyperperfusion was confirmed by measuring portal flow. The portal vascular tree was visualized by injection of a contrast agent followed by CT imaging of explanted livers. Control groups consisted of 70% PHx, rPVL, and sham operation.

RESULTS

The size of the ligated right lobe increased to 1.4-fold on postoperative day 7 when subjected to rPVL + 70% PHx. The right lobe increased to 3-fold when subjected to 70% PHx alone and decreased to 0.3-fold when subjected to rPVL only. The small but significant increase in liver weight after the combined procedure was accompanied by a low proliferative response. In contrast, hepatocyte proliferation was undetectable in the right lobe undergoing atrophy after PVL only. The caudate lobe in the rPVL + 70% PHx group increased to 4.6-fold, which is significantly more than in the other groups. This increase in liver weight was paralleled by persisting portal hyperperfusion and a prolonged proliferative phase of 3 days.

CONCLUSIONS

A discontinued portal blood supply does not always result in atrophy of the ligated lobe. The concurrent regenerative stimulus induced by 70% PHx seemed to counteract the local atrophy after a simultaneously performed rPVL, leading to a low but prolonged regenerative response of the portally deprived liver lobe. This observation supports the conclusion that portal flow is not necessary for liver regeneration. The persisting portal hyperperfusion may be crucial for the specific kinetics of prolonged liver regeneration after rPVL + 70% PHx in the portally supplied caudate lobe. Both observations deserve more attention regarding the underlying mechanism in further studies.

An updated systematic review of the evolution of ALPPS and evaluation of its advantages and disadvantages in accordance with current evidence

The main obstacle to achieving an R0 resection after a major hepatectomy is inability to preserve an adequate future liver remnant (FLR) to avoid postoperative liver failure (PLF). Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a novel technique for resecting tumors that were previously considered unresectable, and this technique results in a vast increase in the volume of the FLR in a short period of time. However, this technique continues to provoke heated debate because of its high mortality and morbidity.The evolution of ALPPS and its advantages and disadvantages have been systematically reviewed and evaluated in accordance with current evidence. Electronic databases (PubMed and Medline) were searched for potentially relevant articles from January 2007 to January 2016.ALPPS has evolved into various modified forms. Some of these modified techniques have reduced the difficulty of the procedure and enhanced its safety. Current evidence indicates that the advantages of ALPPS are rapid hypertrophy of the FLR, the feasibility of the procedure, and a higher rate of R0 resection in comparison to other techniques. However, ALPPS is associated with worse major complications, more deaths, and early tumor recurrence.Hepatobiliary surgeons should carefully consider whether to perform ALPPS. Some modified forms of ALPPS have reduced the mortality and morbidity of the procedure, but they cannot be recommended over the original procedure currently. Portal vein embolization (PVE) is still the procedure of choice for patients with a tumor-free FLR, and ALPPS could be used as a salvage procedure when PVE fails. More persuasive evidence needs to be assembled to determine whether ALPPS or two-stage hepatectomy (TSH) is better for patients with a tumor involving the FLR. Evidence with regard to long-term oncological outcomes is still limited. More meticulous comparative studies and studies of the 5-year survival rate of ALPPS could ultimately help to determine the usefulness of ALPPS. Indications and patient selection for the procedure need to be determined.

Present status and future perspectives of ALPPS (associating liver partition and portal vein ligation for staged hepatectomy)

First International Consensus Meeting, Hamburg, Germany, 27-28 February 2015 More than 160 participants took part in the conference for 2 days. A total of 58 world renown experts on ALPPS (associating liver partition and portal vein ligation for staged hepatectomy) were invited from all over the world. The faculty was divided into many different subgroups that were in contact during the 2-3 months before the conference analyzing all the most important aspects of this technique and summarizing it in a common structured work to be presented during the congress, giving final recommendations in the form of bulleted point statements. The aim was to gain a solid basis of preliminary agreement on many controversial aspects of ALPPS. A poster area was also organized with 35 posters reporting mostly mono-institutional experiences on single aspects of the technique from all five continents.

How we do it: double in situ split for staged mesohepatectomy in patients with advanced gall bladder cancer and marginal future liver remnant

PURPOSE

Associating liver partition with portal vein ligation for staged hepatectomy (ALPPS) has increased the rate of liver resections in patients with marginal future liver remnant. We here describe a modified ALPPS procedure with splitting-off the central liver segments for staged mesohepatectomy in patients with advanced gall bladder cancer.

METHODS

A double in situ split for ALPPS (DALPPS) is performed with splitting-off the central liver segments (segments 1, 4, 5, and 8). This induces a rapid hypertrophy of the left lateral (segments 2/3) and right posterior sectors (segments 6/7). An intrahepatic right posterior approach during splitting-off the right posterior sector is introduced as a part of this new procedure. This approach facilitates the dissection and ligation of the right anterior branch of the portal vein (segments 5 and 8) while the liver hilum remains untouched during the first step of surgery.

RESULTS

Two patients with advanced gall bladder cancer were treated with the DALPPS procedure till date. After a short interval (7-9 days), a rapid hypertrophy of the left lateral and right posterior sector was observed (hypertrophy up to 72.6 and 54.6 %, respectively). A staged mesohepatectomy including caudate lobectomy and resection of the extrahepatic bile duct was then performed safely. There was no surgical-technical morbidity. No signs of posthepatectomy liver failure according to the 50-50 criteria were seen. However, one patient died from severe ARDS attributed to the preoperative chemotherapy. Nevertheless, this complication is deemed to be surgery related.

CONCLUSIONS

The DALPPS procedure is a new surgical technique for staged mesohepatectomy for patients with small future liver remnant in size or in function. However, appropriate patient selection is mandatory to avoid morbidity and mortality.

'Liver-first' approach for metastatic colorectal cancer

The liver-first approach was proposed for the first time in 2006 to obtain resectability of stage IV colorectal cancer patients and complete the therapeutic plan. From then some groups have used this new revolutionary approach reporting promising results. Other alternative strategies have been proposed for metastatic patients. The authors reviewed the literature weighing the pros and cons of each strategy proposed to manage these advanced tumor stages. The therapeutic options are analyzed in the light of oncologic problems and evidence. Also problems, questions and perspectives are given. Even if the 'liver-first' approach seems to be a promising strategy, the ideal diagnostic-therapeutic flowchart for metastatic colorectal cancer is still difficult to standardize. The great heterogeneity of this population of patients is one of the main problems. A 'tailored approach' philosophy is necessary to calibrate, in a multidisciplinary setting, a case-by-case choice of therapeutic options.

Early survival and safety of ALPPS: first report of the International ALPPS Registry

OBJECTIVES

To assess safety and outcomes of the novel 2-stage hepatectomy, Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS), using an international registry.

BACKGROUND

ALPPS induces accelerated growth of small future liver remnants (FLR) to allow curative resection of liver tumors. There is concern about safety based on reports of higher morbidity and mortality.

METHODS

A Web-based data entry system was created with password access and data pseudoencryption (NCT01924741). All patients with complete 90-day data were included. Multivariate logistic regression analysis was performed to identify independent risk factors for severe complications and mortality and volume growth of the FLR.

RESULTS

Complete data were available for 202 patients. A total of 141 (70%) patients had colorectal liver metastases (CRLM). Median starting standardized future liver remnants of 21% increased by 80% within a median of 7 days. Ninety-day mortality was 19/202 (9%). Severe complications including mortalities (Clavien-Dindo≥IIIb) occurred in 27% of patients. Independent factors for severe complications were red blood cell transfusion [odds ratio (OR), 5.2), ALPPS stage I operating time greater than 300 minutes (OR, 4.4), age more than 60 years (OR, 3.8), and non-CRLM (OR, 2.7). Age, use of Pringle maneuver, and histologic changes led to less volume growth. In patients younger than 60 years with CRLM, 90-day mortality was similar to conventional 2-stage hepatectomies for CRLM.

CONCLUSIONS

This is the first analysis of the ALPPS registry showing that ALPPS has increased perioperative morbidity and mortality in older patients but better outcomes in patients with CRLM.

ALPPS: from human to mice highlighting accelerated and novel mechanisms of liver regeneration

OBJECTIVES

To develop a reproducible animal model mimicking a novel 2-staged hepatectomy (ALPPS: Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy) and explore the underlying mechanisms.

BACKGROUND

ALPPS combines portal vein ligation (PVL) with liver transection (step I), followed by resection of the deportalized liver (step II) within 2 weeks after the first surgery. This approach induces accelerated hypertrophy of the liver remnant to enable resection of massive tumor load. To explore the underlying mechanisms, we designed the first animal model of ALPPS in mice.

METHODS

The ALPPS group received 90% PVL combined with parenchyma transection. Controls underwent either transection or PVL alone. Regeneration was assessed by liver weight and proliferation-associated molecules. PVL-treated mice were subjected to splenic, renal, or pulmonary ablation instead of hepatic transection. Plasma from ALPPS-treated mice was injected into mice after PVL. Gene expression of auxiliary mitogens in mouse liver was compared to patients after ALPPS or PVL.

RESULTS

The hypertrophy of the remnant liver after ALPPS doubled relative to PVL, whereas mice with transection alone disclosed minimal signs of regeneration. Markers of hepatocyte proliferation were 10-fold higher after ALPPS, when compared with controls. Injury to other organs or ALPPS-plasma injection combined with PVL induced liver hypertrophy similar to ALPPS. Early initiators of regeneration were significantly upregulated in human and mice.

CONCLUSIONS

ALPPS in mice induces an unprecedented degree of liver regeneration, comparable with humans. Circulating factors in combination with PVL seem to mediate enhanced liver regeneration, associated with ALPPS.

ALPPS and simultaneous right hemicolectomy - step one and resection of the primary colon cancer

Background

Resection of the liver is often limited due to the volume of the parenchyma. To address this problem, several approaches to induce hypertrophy were developed. Recently, the ‘associating liver partition and portal vein ligation for staged hepatectomy’ (ALPPS) procedure was introduced and led to rapid hypertrophy in a short interval. Additionally to the portal vein occlusion, the parenchyma is transected, which disrupts the inter-parenchymal vascular connections.

Since the first description of the ALPPS procedure, various reports around the world were published. In some cases, due to the high morbidity and mortality, a decent oncologic algorithm is not deliverable in a timely manner. If a patient is to be treated with a liver-first approach, the resection of the primary could sometimes be severely protracted. To overcome the problem, a simultaneous resection of the primary tumor and step one of ALPPS were performed.

Case presentation

A 73-year-old male patient underwent portal vein embolization (PVE) after suffering from a synchronous hepatic metastasized carcinoma of the right colic flexure in order to perform a right trisectionectomy. Sufficient hypertrophy could not be obtained by PVE. Thus a ‘Rescue-ALPPS’ was undertaken. During step one of ALPPS, we simultaneously performed a right hemicolectomy. The postoperative course after the first step was uneventful, and sufficient hypertrophy was achieved.

Conclusion

In order to achieve a macroscopic disease-free state and lead the patient as soon as possible to the oncologic path (with, for example, chemotherapy), sometimes a simultaneous resection of the primary with step one of the ALPPS procedure seems justified. A resection of the primary with step two is not advisable, due to the high morbidity and mortality after this step. This case shows that a simultaneous resection is feasible and safe. Whether other locations of the primary should be treated this way must be part of further investigations.

Challenges in the multidisciplinary management of stage IV colon and rectal cancer

Colorectal metastases still represent a challenge to all oncologists despite progresses achieved by improved resectability, systemic chemotherapy and targeted therapies. In particular in patients with oligo-metastases, the role of surgical resections has been redefined. Resection is the most effective treatment method for liver metastases performed with curative intent; however, primary rate of resectability is low. Several methods to increase resectability have been developed: conversion chemotherapy, portal vein embolization, two-stage resections, vascular reconstruction of the liver veins, combination of resection and intraoperative ablation. Liver resections can be performed at present with low mortality. Patients with isolated peritoneal metastases, no extra-abdominal disease, low volume tumor and complete surgical cytoreduction do benefit from surgery and hyperthermic intraperitoneal chemotherapy. Several national guidelines recommend multimodality treatment for highly selected patients. The management of stage IV colorectal cancer includes several disciplines with focus on resection. A multidisciplinary evaluation of all patients is of crucial importance to define the treatment sequence and individual strategies for each patient.

ALPPS for patients with colorectal liver metastases: effective liver hypertrophy, but early tumor recurrence

BACKGROUND

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a promising method to increase resectability rates of liver tumors. Little has been published about oncological results so far. This report describes clinical evidence regarding a possible effect of ALPPS on tumor recurrence.

METHODS

Ten ALPPS procedures were performed for otherwise non-resectable colorectal liver metastases. Seven of these ten patients had a follow-up of at least 3 months and were analyzed for tumor recurrence.

RESULTS

Six of these seven patients had tumor recurrence to the liver. Three of seven patients presented with lung metastases, occurring earlier than liver metastases in two of three cases. One patient with a follow-up of 3 months had no visible recurrent disease, but increasing carcinoembryonic antigen levels.

CONCLUSIONS

The patient group operable only through ALPPS is at high risk for recurrence and early tumor progression. Still, this new method is the only chance for an oncological treatment strategy including a surgical approach and possibly better outcome.

ALPPS: challenging the concept of unresectability--a systematic review

INTRODUCTION

Hepatic resection for malignancy is limited by the amount of liver parenchyma left behind. As a result, two-staged hepatectomy and portal vein occlusion (PVO) have become part of the treatment algorithm. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has been recently described as a method to stimulate rapid and profound hypertrophy.

MATERIALS AND METHODS

A systematic review of the literature pertaining to ALPPS was undertaken. Peer-reviewed articles relating to portal vein ligation (PVL) and in situ split (ISS) of the parenchyma were included.

RESULTS

To date, ALPPS has been employed for a variety of primary and metastatic liver tumors. In early case series, the perioperative morbidity and mortality was unacceptably high. However with careful patient selection and improved technique, many centers have reported a 0% 90-day mortality. The benefits of ALPPS include hypertrophy of 61-93% over a median 9-14 days, 95-100% completion of the second stage, and high likelihood of R0 resection (86-100%).

DISCUSSION

ALPPS is only indicated when a two-stage hepatectomy is necessary and the future liver remnant (FLR) is deemed inadequate (<30%). Use in patients with poor functional status, or advanced age (>70 years) is cautioned. Discretion should be used when considering this in patients with pathology other than colorectal liver metastases (CRLM), especially hilar tumors requiring biliary reconstruction. Biliary ligation during the first stage and routine lymphadenectomy of the hepatoduodenal ligament should be avoided.

CONCLUSIONS

A consensus on the indications and contraindications for ALPPS and a standardized operative protocol are needed.

Rodent models and imaging techniques to study liver regeneration

The liver has the unique capability of regeneration from various injuries. Different animal models and in vitro methods are used for studying the processes and mechanisms of liver regeneration. Animal models were established either by administration of hepatotoxic chemicals or by surgical approach. The administration of hepatotoxic chemicals results in the death of liver cells and in subsequent hepatic regeneration and tissue repair. Surgery includes partial hepatectomy and portal vein occlusion or diversion: hepatectomy leads to compensatory regeneration of the remnant liver lobe, whereas portal vein occlusion leads to atrophy of the ipsilateral lobe and to compensatory regeneration of the contralateral lobe. Adaptation of modern radiological imaging technologies to the small size of rodents made the visualization of rodent intrahepatic vascular anatomy possible. Advanced knowledge of the detailed intrahepatic 3D anatomy enabled the establishment of refined surgical techniques. The same technology allows the visualization of hepatic vascular regeneration. The development of modern histological image analysis tools improved the quantitative assessment of hepatic regeneration. Novel image analysis tools enable us to quantify reliably and reproducibly the proliferative rate of hepatocytes using whole-slide scans, thus reducing the sampling error. In this review, the refined rodent models and the newly developed imaging technology to study liver regeneration are summarized. This summary helps to integrate the current knowledge of liver regeneration and promises an enormous increase in hepatological knowledge in the near future.

Patients with multiple synchronous colonic cancer hepatic metastases benefit from enrolment in a “liver first” approach protocol

AIM: To assess a protocol for treating patients with multiple synchronous colonic cancer liver metastases, which are unresectable in one stage.

METHODS: Patients enrolled in the “liver first” protocol presented with colon-only (not rectal) cancer and multiple synchronous hepatic metastases (type II or III). All patients showed good performance status (ECOG PS 0-1) and were treated with curative intent. Complete oncologic staging including positron emission tomography-computed tomography was performed in order to rule out extrahepatic disease. If bowel obstruction was imminent, an intraluminal colonic stent was placed endoscopically. Subsequently, all patients received standardised neo-adjuvant chemotherapy, that is, FOLFOX or XELOX regimens combined with an antiangiogenic agent (bevacizumab or cetuximab). Provided that a response to chemotherapy was observed, patients underwent either one or two hepatectomies with or without portal vein embolization followed by the indicated colectomy. Further chemotherapy was administered after each procedure. Re-staging was performed after each chemotherapeutic treatment. Disease progression at any stage resulted in discontinuation of the protocol and conversion to palliative disease management.

RESULTS: Prospectively recorded data from 11 consecutive patients (8 men) were analysed for this study. Their mean age at the time of their first assessment was 65.7 (SD ± 15.3) years. Six (54.6%) patients presented with type III metastatic disease. The minimum and maximum follow-up periods were 7.3 and 39.6 mo, respectively. The mean overall survival of all patients was 16.5 (95%CI: 10.0-23.2) mo. A colonic stent had to be placed in 5 (45.5%) patients due to the onset of an intraluminal obstruction. Four (36.4%) patients succeeded in completing all planned surgical operations. Their mean overall survival was 27.2 (95%CI: 15.1-39.3) mo and the mean disease-free survival was 7.7 (95%CI: 3.0-12.5) mo. Patients, who were obliged to shift to palliative treatment due to disease progression, had a mean overall survival of 10.5 (95%CI: 8.6-12.4) mo. None of these patients underwent palliative colectomy. No postoperative mortality was recorded.

CONCLUSION: The implementation of a structured “liver first” approach protocol for the treatment of patients with extensive, liver-limited colon cancer metastatic disease may be beneficial.