Role of portal vein embolization in liver surgery: single centre experience in sixty-two patients

Factors influencing failure of progression to completion hepatectomy following liver venous deprivation procedures (PVE or DVE): a longitudinal observational study

BACKGROUND

Two-staged hepatectomy (TSH) with portal (PVE) or dual vein embolization (DVE) gained acceptance in liver surgery. The current study assesses the incidence and causes of failure to progress to completion hepatectomy following PVE/DVE and its influence on overall survival (OS).

METHODS

This is a longitudinal observational study of patients who underwent PVE or DVE between April 2010-December 2023. Future liver remnant (FLR) volume was measured at least four weeks later. Restaging and resectability was assessed on imaging performed within 6-8 weeks of planned completion surgery.

RESULTS

130 patients underwent PVE (90) or DVE (40) during the study period. Of these, 73 (56 %) patients proceeded to definitive resection. Reasons for failure to progress to completion surgery were: disease progression (79 %), declined fitness for surgery (3.5 %) and inadequate FLR volume (14 %). Synchronous disease is a poor prognostic factor for achieving completion hepatectomy CRLM patients (p = 0.009). The median OS with and without completion hepatectomy was 38 months vs. 13 months in CRLM patients (p=<.001) and 31 months vs. 26 months in pCCA groups respectively (p = 0.471).

CONCLUSION

A significant percentage of patients did not progress to completion hepatectomy due to disease progression. Patient selection and efficient pathways are essential to improve resection rates following these resource-intensive procedures.

Cornerstones and divergencies in the implementation and use of liver hypertrophy techniques: results from a nationwide survey for the set-up of the prospective registry

BACKGROUND

The aim of this national survey on liver hypertrophy techniques was to track the trends of their use and implementation in Italy and to detect analogies and heterogeneities among centers.

METHODS

In December 2022, Italian centers with liver resection activity were specifically contacted and asked to fill an online questionnaire composed of 6 sections including a total of 51 questions.

RESULTS

46 Italian centers filled the questionnaire. The proportion of major/total number of liver resections was 27% and the use of hypertrophy techniques was required in 6,2% of cases. The most frequent reason of drop out was disease progression in 58.5% of cases. Most frequently used techniques were PVE and ALPPS with an increasing use of hepatic venous deprivation (HVD). Heterogeneous answers were provided regarding the cutoff values to indicate the need for hypertrophy techniques. Criteria to allocate a patient to different hypertrophy techniques are not standardized.

CONCLUSIONS

The use of hypertrophy techniques is deep-rooted in Italy, documenting the established value of their role in improving resectability rate. While an evolution of techniques is detectable, still significant heterogeneity is perceived in terms of cutoff values, indications and managing protocols.

Contemporary Surgical Management of Colorectal Liver Metastases

Colorectal cancer is the third most common cancer in the United States and the second most common cause of cancer-related death. Approximately 20-30% of patients will develop hepatic metastasis in the form of synchronous or metachronous disease. The treatment of colorectal liver metastasis (CRLM) has evolved into a multidisciplinary approach, with chemotherapy and a variety of locoregional treatments, such as ablation and portal vein embolization, playing a crucial role. However, resection remains a core tenet of management, serving as the gold standard for a curative-intent therapy. As such, the input of a dedicated hepatobiliary surgeon is paramount for appropriate patient selection and choice of surgical approach, as significant advances in the field have made management decisions extremely nuanced and complex. We herein aim to review the contemporary surgical management of colorectal liver metastasis with respect to both perioperative and operative considerations.

Predicting futility of upfront surgery in perihilar cholangiocarcinoma: Machine learning analytics model to optimize treatment allocation

BACKGROUND

While resection remains the only curative option for perihilar cholangiocarcinoma, it is well known that such surgery is associated with a high risk of morbidity and mortality. Nevertheless, beyond facing life-threatening complications, patients may also develop early disease recurrence, defining a "futile" outcome in perihilar cholangiocarcinoma surgery. The aim of this study is to predict the high-risk category (futile group) where surgical benefits are reversed and alternative treatments may be considered.

METHODS

The study cohort included prospectively maintained data from 27 Western tertiary referral centers: the population was divided into a development and a validation cohort. The Framingham Heart Study methodology was used to develop a preoperative scoring system predicting the "futile" outcome.

RESULTS

A total of 2271 cases were analyzed: among them, 309 were classified within the "futile group" (13.6%). American Society of Anesthesiology (ASA) score ≥ 3 (OR 1.60; p = 0.005), bilirubin at diagnosis ≥50 mmol/L (OR 1.50; p = 0.025), Ca 19-9 ≥ 100 U/mL (OR 1.73; p = 0.013), preoperative cholangitis (OR 1.75; p = 0.002), portal vein involvement (OR 1.61; p = 0.020), tumor diameter ≥3 cm (OR 1.76; p < 0.001), and left-sided resection (OR 2.00; p < 0.001) were identified as independent predictors of futility. The point system developed, defined three (ie, low, intermediate, and high) risk classes, which showed good accuracy (AUC 0.755) when tested on the validation cohort.

CONCLUSIONS

The possibility to accurately estimate, through a point system, the risk of severe postoperative morbidity and early recurrence, could be helpful in defining the best management strategy (surgery vs. nonsurgical treatments) according to preoperative features.

Results from the european survey on preoperative management and optimization protocols for PeriHilar cholangiocarcinoma

BACKGROUND

Major surgery, along with preoperative cholestasis-related complications, are responsible for the increased risk of morbidity and mortality in perihilar cholangiocarcinoma (pCCA). The aim of the present survey is to provide a snapshot of current preoperative management and optimization strategies in Europe.

METHODS

61 European centers, experienced in hepato-biliary surgery completed a 59-questions survey regarding pCCA preoperative management. Centers were stratified according to surgical caseload (<5 and ≥ 5 cases/year) and preoperative management protocols' application.

RESULTS

The overall case volume consisted of 6333 patients. Multidisciplinary discussion was routinely performed in 91.8% of centers. Most respondents (96.7%) recognized the importance of a well-structured preoperative protocol. The preferred method for biliary drainage was percutaneous transhepatic biliary drainage (60.7%) while portal vein embolization was the preferred technique for liver hypertrophy (90.2%). Differences in preoperative pathologic confirmation of malignancy (35.8% vs 28.7%; p < 0.001), number of mismanaged referred patients (88.2% vs 50.8%; p < 0.001), biliary drainage (65.1% vs 55.6%; p = 0.015) and liver function evaluation (37.2% vs 5.6%; p = 0.001) were found between centers according to groups' stratification.

CONCLUSION

The importance of a correct preoperative management is recognized. Nevertheless, the current lack of guidelines leads to wide heterogeneity of behaviors among centers. This survey can provide recommendations to improve pCCA perioperative outcomes.

The failure to rescue factor: aftermath analyses on 224 cases of perihilar cholangiocarcinoma

The term "failure to rescue" (FTR) has been recently introduced in the field of hepato-biliary surgery to label cases in which major postoperative complications lead to postoperative fatality. Perihilar cholangiocarcinoma (PHC) surgery has consistently high postoperative morbidity and mortality rates in which factors associated with FTR are yet to be discovered. The primary endpoint of this study is to compare the Rescue with the FTR cohort referencing patients' characteristics and management protocols applied. A cohort of 224 consecutive patients undergoing surgery for PHC, between 2010 and 2021, was enrolled. Perioperative variables were analyzed according to the severity of major postoperative complications (Clavien ≥ 3a). Kaplan-Meier survival analyses were performed to determine complications' impact on survival. Major complications were reported in 86 cases (38%). Among the major complications' cohort, 72 cases (84%) were graded Clavien 3a-4 (Rescue group), while 14 (16%) cases were graded Clavien 5 (FTR group). Number of lymph-node metastases (OR = 1.33 (1.08-1.63) p = 0.006), poorly differentiated (G3) adenocarcinoma (OR = 7.55 (1.24-45.8) p = 0.028, reintervention (OR = 16.47 (2.76-98.08) p = 0.002), and prognostic nutritional index < 40 (OR = 3.01 (2.265-3.654) p < 0.001) rates were independent predictors of FTR. Right resection side (OR 2.4 (1.33-4.34) p = 0.004) increased the odds of major complications but not of FTR. No difference in overall survival was identified. A distinction of perioperative factors associated with postoperative complications' severity is crucial. Patients developing severe outcomes seem to have different biological and nutritional profiles, showing that efficient preoperative protocols are strategic to identify and avert the risk of FTR.

Radial and longitudinal margins in surgery of perihilar cholangiocarcinoma: When R1 definition is associated with different prognosis

BACKGROUND

Infiltrated margins of resection (R1) and lymph node invasion are dominant negative predictors of survival in patients with a resectable perihilar cholangiocarcinoma. Less clear is whether survival predictors stratify differently between R0 (tumor-free margins) and R1 patients and whether the prognosis of the latter patients is influenced by the pattern of neoplastic infiltration (ie, radial versus longitudinal infiltration). We retrospectively evaluated a series of reported resected perihilar cholangiocarcinoma to obtain insights on the predictive power of these histologic features.

METHODS

The study includes 264 patients with perihilar cholangiocarcinoma treated between 2004 and 2019 in our center and followed up for >18 months. There were 176 patients with R0 (66.6%) and 88 patients with R1 (33.3%), 31 with radial infiltration only, 30 with longitudinal infiltration only, and 27 with both infiltration patterns. In all patients, the criteria for resection was the absence of metastatic involvement (ie, distant organ metastases, liver metastases, and lymph node metastases beyond the hepatoduodenal ligament). Histopathologic specimens of the resected tumors were centrally reviewed by a pathologist unaware of the clinical outcomes.

RESULTS

Three- and 5-year long-term survival were significantly better in R0 (respectively) compared to R1 patients (55% and 42% vs 42% and 18%, respectively, P < .05). In R1 patients with radial infiltration only and those with radial + longitudinal infiltration, both disease-free and overall survival were worse than those with longitudinal infiltration only (median disease-free survival of 18 and 23 months, respectively, P < .05, median overall survival of 33 and 39 months, respectively, P < .05). At multivariable analysis, nodal status, side of hepatectomy, grading, and presence of radial margin infiltration were associated with long-term outcome.

CONCLUSION

Radial infiltration of resection margins enhances the negative prognostic value of R1 margins in perihilar cholangiocarcinoma patients and should specifically be accounted for in the prediction of the outcome of adjuvant therapy.

Evolution of Surgical Treatment of Colorectal Liver Metastases in the Real World: Single Center Experience in 1212 Cases

BACKGROUND

In recent years, the treatment of colorectal liver metastases (CRLM) has undergone significant evolution thanks to technical improvements as well as oncological advances, which have been the subject of targeted studies aimed at understanding the details of this heterogeneous disease. The purpose of this study is to put together pieces of this complex scenario by providing an overview of the evolution that has occurred in the context of a single center within a multidisciplinary management approach.

METHODS

Between 2005 and 2020, 1212 resections for CRLM were performed at the Hepatobiliary Surgery Division of San Raffaele Hospital, Milan. The series was divided into three historical periods, which were compared in terms of disease characteristics and short- and long-term outcomes: Period 1, 2005-2009 (293 cases); Period 2, 2010-2014 (353 cases); Period 3, 2015-2020 (566 cases). The trends for surgical technical complexity, oncological burden of the disease, use of the laparoscopic approach and use of techniques for hepatic hypertrophy were analyzed year by year. Uni- and multivariate analyses were performed to identify factors associated with inclusion to a laparoscopic approach and with long-term prognosis.

RESULTS

The number of resections performed over the years progressively increased, with an increase in the number of cases with a high Clinical Risk Score and a high profile of technical complexity. The proportion of cases performed laparoscopically increased, but less rapidly compared to other malignant tumors. The risk of postoperative morbidity and mortality was similar in the three analyzed periods. Long-term survival, stratified by Clinical Risk Score, improved in Period 3, while overall survival remained unchanged.

CONCLUSION

The cultural background, the maturation of technical expertise and the consolidation of the multidisciplinary team have resulted in safe expansion of the possibility to offer a curative opportunity to patients, while continuously implementing into clinical practice evidence provided by the literature.

Portal vein embolization with N-butyl cyanoacrylate glue is superior to other materials: a systematic review and meta-analysis

OBJECTIVES

It remains uncertain which embolization material is best for portal vein embolization (PVE). We investigated the various materials for effectiveness in inducing future liver remnant (FLR) hypertrophy, technical and growth success rates, and complication and resection rates.

METHODS

A systematic review from 1998 to 2019 on embolization materials for PVE was performed on Pubmed, Embase, and Cochrane. FLR growth between the two most commonly used materials was compared in a random effects meta-analysis. In a separate analysis using local data (n = 52), n-butyl cyanoacrylate (NBCA) was compared with microparticles regarding costs, radiation dose, and procedure time.

RESULTS

In total, 2896 patients, 61.0 ± 4.0 years of age and 65% male, from 51 papers were included in the analysis. In 61% of the patients, either NBCA or microparticles were used for embolization. The remaining were treated with ethanol, gelfoam, or sclerosing agents. The FLR growth with NBCA was 49.1% ± 29.7 compared to 42.2% ± 40 with microparticles (p = 0.037). The growth success rate with NBCA vs microparticles was 95.3% vs 90.7% respectively (p < 0.001). There were no differences in major complications between NBCA and microparticles. In the local analysis, NBCA (n = 41) entailed shorter procedure time and reduced fluoroscopy time (p < 0.001), lower radiation exposure (p < 0.01), and lower material costs (p < 0.0001) than microparticles (n = 11).

CONCLUSION

PVE with NBCA seems to be the best choice when combining growth of the FLR, procedure time, radiation exposure, and costs.

KEY POINTS

• The meta-analysis shows that n-butyl cyanoacrylate (NBCA) is superior to microparticles regarding hypertrophy of the future liver remnant, 49.1% ± 29.7 vs 42.2% ± 40.0 (p = 0.037). • There is no significant difference in major complication rates for portal vein embolization using NBCA, 4% (24/681), compared with microparticles, 5% (25/494) (p > 0.05). • Local data shows a shorter procedure time, 215 vs 348 mins from arrival to departure at the interventional radiology unit, and fluoroscopy time, 43 vs 96 mins (p < 0.001), lower radiation dosage, 573 vs 1287 Gycm² (p < 0.01), and costs, €816 vs €4233 (p < 0.0001) for NBCA compared to microparticles.

Preoperative Portal Vein Embolization for Liver Resection: An updated meta-analysis

Background: Portal vein embolization (PVE) is performed before major liver resection to increase liver volume remnant, controversy remains on the adverse effect of PVE on liver tumor patients. The current study highlighted the effect of PVE on the degree of hypertrophy of future liver remnant (FLR) and summarized PVE-related complications, aiming to provide a guideline for surgeons.

Methods: A search of current published studies on PVE was performed. Meta-analysis was conducted to assess the effect of PVE on hypertrophy of FLR and summarized PVE-related complications.

Results: 26 studies including 2335 patients were enrolled in the meta-analysis. All enrolled studies reported data regarding FLR hypertrophy rate, pooled effect size (ES) for FLR hypertrophy rate using a fixed-effect model was 0.105 (95%CI: 0.094-0.117, p=0.000), indicating PVE is favored in inducing FLR hypertrophy. Metatrim method indicated no obvious evidence of publication bias in the present meta-analysis. 247 (10.6%) patients exhibited PVE-related complications, receiving expectant treatment without affecting planned liver resection. Total 1782 patients (76%) underwent a subsequent liver resection after PVE, which is an encouraging result comparing with traditional resection rate in liver tumor patients.

Conclusions: PVE is a safe and effective procedure with a low occurrence of related complications for inducing sufficient hypertrophy of FLR in liver tumor patients, which could elevate the resection rate of liver tumor patients. Careful patient cohort selection is crucial to avoid overuse of PVE in technically resectable patients. Further multiple central clinical trials are conducive to select optimal patient cohorts and provide a guideline for surgeons.

A stepwise learning curve to define the standard for technical improvement in laparoscopic liver resections: complexity-based analysis in 1032 procedures

The objective of this study is to define the learning curve in a series of procedures grouped according to their complexity calculated by difficulty index to define a standard for technical improvement. 1032 laparoscopic liver resections performed in a single tertiary referral center were stratified by difficulty scores: low difficulty (LD, n = 362); intermediate difficulty (ID, n = 332), and high difficulty (HD, n = 338). The learning curve effect was analyzed using the cumulative sum (CUSUM) method taking into consideration the expected risk of conversion. The ratio of laparoscopic/total liver resections increased from 5.8% (2005) to 71.1% (2018). The CUSUM analysis per group showed that the average value of the conversion rate was reached at the 60th case in the LD Group and at the 15th in the ID and HD groups. The evolution from LD to ID and HD procedures occurred only when learning curve in LD resections was concluded. Reflecting different degree of complexity, procedures showed significantly different blood loss, morbidity, and conversions among groups. A standard educational model-stepwise and progressive-is mandatory to allow surgeons to define the technical and technological backgrounds to deal with a specific degree of difficulty, providing a help in the definition of indications to laparoscopic approach in each phase of training.

Management of hilum infiltrating tumors of the liver: The impact of experience and standardization on outcome

BACKGROUND

The primary endpoint of this study was to evaluate the outcome of surgery for perihilar cholangiocarcinoma in a high-volume tertiary referral center.

METHODS

The study population consisted of 196 consecutive patients with histologically confirmed perihilar cholangiocarcinoma-PHC-who were candidates to surgical treatment. Factors affecting postoperative morbidity were evaluated in the whole series (primary endpoint) and after stratification of patients according to the following criteria: (a) perioperative management protocol implementation; (b) monocentric management (secondary endpoint).

RESULTS

The postoperative morbidity rate was 51.5% and mortality 4.1%. The most frequent cause of death was postoperative liver failure. At multivariate analysis, factors affecting the risk of morbidity were: side of hepatectomy, liver volume, intraoperative blood loss, preoperative optimization and single-center management. Patients treated according to preoperative optimization protocol, as well as patients with monocentric management experienced a significant reduction of postoperative morbidity. Preoperative optimization and single-center management significantly affected even long term outcome of patients.

CONCLUSION

Despite continuous improvement in the surgical field, hilum-infiltrating tumors still remain associated with therapeutic and management challenges: a correct preoperative management in a tertiary referral center provides a benefit in terms of morbidity and mortality, thus improving long term results.

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.

Serum levels of endothelin-1 after liver resection as an early predictor of postoperative liver failure. A prospective study

AIM

Besides the residual liver volume, damage of the microcirculation secondary to increased portal blood flow is a main determinant of postoperative liver failure (PLF). Endothelin-1 (ET-1), produced by sinusoidal endothelial cells, plays a key role in the regulation of hepatic microcirculation. The aim of this study was to determine whether ET-1 levels has any prognostic utility in predicting PLF.

METHODS

Patients undergoing liver resection for primary or secondary liver tumors at San Raffaele Hospital, Milan, were prospectively enrolled in the study. Serial postoperative serum ET-1 levels in patients undergoing liver resections were correlated with indices of inflammatory response, liver failure and death.

RESULTS

A total of 144 patients were included. ET-1 levels in patients who underwent major or extended liver resection were significantly higher than in patients who had a minor resection on postoperative day (POD) 1 (P = 0.003), POD 2 (P = 0.0001) and POD 5 (P = 0.0001). Eight patients developed PLF and ET-1 was significantly higher compared with patients without PLF on POD 2 (P = 0.002) and POD5 (P = 0.006). Serum ET-1 concentration on POD 2 was an independent predictor of PLF in multivariate analysis.

CONCLUSION

ET-1 is as an early index of PLF and provides a rationale for therapeutic manipulation, with many potential clinical implications to prevent PLF onset and reduce its severity.

Comparative Analysis of Left- Versus Right-sided Resection in Klatskin Tumor Surgery: can Lesion Side be Considered a Prognostic Factor?

BACKGROUND

Achievement of negative margins is the goal of curative intent surgery for hilar cholangiocarcinoma. This study analyzed factors affecting survival in hilar cholangiocarcinoma patients and compared short- and long-term outcomes of left- and right-sided resections.

METHODS

One hundred and five patients out of 124 diagnosed with Klatskin tumors underwent major liver resection. Sixty-one patients underwent right-sided resections (right group), whereas 44 underwent left-sided resections (left group). Perioperative morbidity, perioperative mortality, and overall and disease-free survival were compared between the groups.

RESULTS

Morbidity and mortality were higher in the right group (59 and 8.2%, respectively) than in the left group (38.6 and 2.3%, respectively) (p < 0.005). The most frequent cause of death was liver failure. The R0 rate was 75.4% in the right and 61.4% in the left group. The 5-year survival rate was 42.8% in the right and 35.3% in the left group (p < 0.05). Patients in the left group more frequently developed local recurrence (87 vs. 69% in the right group).

CONCLUSION

Lesion side impacts outcome: right resections still cause significant morbidity related to extensive parenchymal sacrifice but are associated with better long-term survival because right hepatic pedicle resection enables better radicality compared with left resections.

Liver-directed therapies in metastatic colorectal cancer

Colorectal cancer (CRC) is a major health concern in the United States (US) with over 140,000 new cases diagnosed in 2012. The most common site for CRC metastases is the liver. Hepatic resection is the treatment of choice for colorectal liver metastases (CLM), with a 5-year survival rate ranging from 35% to 58%. Unfortunately, only about 20% of patients are eligible for resection. There are a number of options for extending resection to more advanced patients including systemic chemotherapy, portal vein embolization (PVE), two stage hepatectomy, ablation and hepatic artery infusion (HAI). There are few phase III trials comparing these treatment modalities, and choosing the right treatment is patient dependent. Treating hepatic metastases requires a multidisciplinary approach and knowledge of all treatment options as there continues to be advances in management of CLM. If a patient can undergo a treatment modality in order to increase their potential for future resection this should be the primary goal. If the patient is still deemed unresectable then treatments that lengthen disease-free and overall-survival should be pursued. These include chemotherapy, ablation, HAI, chemoembolization, radioembolization (RE) and stereotactic radiotherapy.

Portal vein embolization and ligation for extended hepatectomy

Portal vein occlusion through embolization or ligation (PVE, PVL) offers the possibility of increasing the future liver remnant (FLR) and thus reducing the risk of hepatic failure after extended hepatectomy We reviewed the indications, scope and applicability of PVE/PVL in treatment of primary and secondary liver tumours. A thorough PubMED, Embase, Ovid and Cochrane database search was carried out for all original articles with 30 patients or more undergoing either PVE and any patient series with PVL, irrespective of number with outcome measure in at least one of the following parameters: FLR volume change, complications, length of stay, time to surgery, proportion resectable and survival data. PVE can be performed with a technical success in 98.9 % (95 % confidence interval 97-100) patients, with a mean morbidity of 3.13 % (95 % CI 1.21-5.04) and a median in-hospital stay of 2.1 (range 1-4) days (very few papers had data on length of stay following PVE). The mean increase in volume of the FLR following PVE was 39.75 % (95 % CI 30.8-48.6) facilitating extended liver resection after a mean of 37.13 days (95 % CI 28.51-45.74) with a resectability rate of 76.88 % (95 % CI 70.91-82.84). Morbidity and mortality following such extended liver resections after PVE is 26.58 % (95 % CI 19.20-33.95) and 2.59 % (95 % CI 1.34-3.83) respectively with an in-patient stay of 13.57 days (95 % CI 9.8-17.37). However following post-PVE liver hypertrophy 6.29 % (95 % CI 2.24-10.34) patients still have post-resection liver failure and up to 14.2 % (95 % CI -8.7 to 37) may have positive resection margins. Up to 4.80 % (95 % CI 2.07-7.52) have failure of hypertrophy after PVE and 17.46 % (95 % CI 11.89-23.02) may have disease progression during the interim awaiting hypertrophy and subsequent resection. PVL has a greater morbidity and duration of stay of 5.72 % (95 % CI 0-15.28) and 10.16 days (95 % CI 6.63-13.69) respectively; as compared to PVE. Duration to surgery following PVL was greater at 53.6 days (95 % CI 32.14-75.05). PVL induced FLR hypertrophy by a mean of 64.65 % (95 % CI 0-136.12) giving a resectability rate of 63.68 % (95 % CI 56.82-70.54). PVL failed to produce enough liver hypertrophy in 7.4 % of patients (95 % CI 0-16.12). Progression of disease following PVL was 29.29 (95%CI 15.69-42.88). PVE facilitates an extended hepatectomy in patients with limited or inadequate FLR, with good short and long-term outcomes. Patients need to be adequately counselled and consented for PVE and EH in light of these data. PVL would promote hypertrophy as well, but clearly PVE has advantages as compared to PVL on account of its inherent "minimally invasive" nature, fewer complications, length of stay and its feasibility to have shorter times to surgery.

Defining indications to ALPPS procedure: technical aspects and open issues

The limit to surgical treatment of patients with hepatic tumors is represented by the proportion of residual hepatic parenchyma at the end of surgery (FLR, future liver remnant) that provides an estimation of the risk of postoperative liver failure. Recently, a new two-stage technique has been developed with the acronym (ALPPS) associating liver partitioning and portal vein ligation for staged hepatectomy with the aim of obtaining a more rapid and effective increase in FLR, even though indications are not clear yet. Between January and December 2012, eight patients were candidates to ALPPS at the Hepatobiliary Surgery Unit of San Raffaele Hospital, Milan. The first three patients (Series 1) underwent right trisectionectomy and were affected by tumors infiltrating biliary confluence, while the others (Series 2) were candidates to right hepatectomy for colorectal liver metastases. Two patients were then excluded from Series 2 because intraoperative finding of irresectable disease. Intra- and postoperative outcome was evaluated with the aim of defining indications to ALPPS. All patients reached an adequate FLR after a median of 7.5 days from the first procedure (rate of program completion 100 %). In Series 1 two patients developed complications related to bile leakage from the raw surface of the liver to be resected and septic events secondary to ischemic necrosis of the liver segment IV. One patient died following multi-organ failure secondary to sepsis. In Series 2 postoperative course was uneventful in all the patients, and in particular no patient showed disease progression between the two procedures or signs of postoperative liver failure. ALPPS approach was initially considered suitable for patients affected by Klatskin tumors who require, despite a small tumor volume, extended hepatectomies associated with surgery of the biliary tract: the analysis of this first series of patients has led to a re-evaluation of the indication to this strategy, as a consequence of encountered criticisms. Actually only a subset of patients affected by colorectal liver metastases are candidates to ALPPS.