The Predictive Value of Indocyanine Green Clearance in Future Liver Remnant for Posthepatectomy Liver Failure Following Hepatectomy with Extrahepatic Bile Duct Resection

Predicting post-hepatectomy liver failure with T1 mapping-based whole-liver histogram analysis on gadoxetic acid-enhanced MRI: comparison with the indocyanine green clearance test and albumin-bilirubin scoring system

OBJECTIVES

To explore the value of T1 mapping-based whole-liver histogram analysis on gadoxetic acid-enhanced MRI for predicting post-hepatectomy liver failure (PHLF).

METHODS

Consecutive patients from March 2016 to March 2018 who underwent gadoxetic acid-enhanced MRI in our hospital were retrospectively analyzed, and 37 patients were enrolled. Whole-liver T1 mapping-based histogram analysis was performed. The indocyanine green (ICG) clearance tests were performed, and albumin-bilirubin (ALBI) scores were calculated. Univariate and multivariate binary logistic analyses were performed to identify independent predictors for PHLF. Diagnostic performance was evaluated with ROC analysis. Histogram-extracted parameters were also associated with the ICG test and ALBI scoring system.

RESULTS

In enrolled 37 patients (age 57.19 ± 12.28 years), 28 were male. 35.1% (13/37) of patients developed PHLF. For univariate analysis, pre-contrast T1 relaxation time (T1pre) mean, T1pre 95th percentile, the standard deviation (SD) of T1 relaxation time in hepatobiliary phase (T1HBP SD), T1HBP 95th percentile, T1HBP kurtosis, and ICG percentage retained at 15 min (ICG-R15) showed significant differences between the PHLF and non-PHLF groups (all p < 0.05), whereas the ALBI scores showed no significant differences between the two groups (p = 0.937). Multivariate analysis showed that a higher T1HBP 95th percentile was the independent predictor for PHLF (p < 0.05; odds ratio (OR) = 1.014). In addition, most of the histogram-extracted parameters showed significant correlations to the ICG test.

CONCLUSIONS

T1 mapping-based whole-liver histogram analysis on gadoxetic acid-enhanced MRI is valuable for PHLF prediction and risk stratification, which outperformed the ICG clearance test and ALBI scoring system.

KEY POINTS

Question What is the value of T1 mapping-based whole-liver histogram analysis on gadoxetic acid-enhanced MRI for PHLF? Findings The histogram parameters extracted from gadoxetic acid-enhanced T1 mapping manifested potential for grading liver function preoperatively. Clinical relevance T1 mapping-based whole-liver histogram analysis on gadoxetic acid-enhanced MRI can serve as a convenient one-station radiological tool to help identify potential PHLF risks within the preoperative clinical decision-making framework.

Effect of Preoperative Autologous Blood Storage in Major Hepatectomy for Perihilar Malignancy: A Randomized Controlled Trial

OBJECTIVE

To reappraise whether preoperative autologous blood donation reduces post-hepatectomy liver failure (PHLF) in major hepatectomy for perihilar malignancy.

SUMMARY BACKGROUND DATA

Autologous blood storage and transfusion are carried out to reduce the use of allogeneic blood transfusion during hepatectomy and prevent postoperative complications. However, the clinical benefit of major hepatectomy has been controversial.

METHODS

This randomized clinical trial included patients who underwent major hepatectomy with extrahepatic bile duct resection for perihilar malignancy. Eligible patients were randomly assigned (1:1) to undergo surgery with or without the use of autologous blood transfusion. The primary outcome was the incidence of clinically relevant PHLF (grade B/C according to the International Study Group of Liver Surgery definition).

RESULTS

Between February 6, 2019, and May 12, 2023, 138 consecutive patients were enrolled in the study (blood storage group n=68, non-storage group n=70). Twenty-five patients who did not undergo resection were excluded; the remaining 113 patients were investigated as the full analysis set (blood storage group n=60, non-storage group n=53). Surgical procedures, operative time, and blood loss were not significantly different between the 2 groups. The incidence of PHLF was comparable [blood storage group n=10 (17%), non-storage group n=10 (19%); P =0.760]. There were also no between-group differences in other postoperative outcomes, including the incidence of Clavien-Dindo Grade Ⅲ or higher (72% vs 72%, P =0.997) and median duration of hospital stay (25 vs 29 days, P =0.277).

CONCLUSIONS

Autologous blood storage did not contribute to reducing the incidence of PHLF in patients undergoing major hepatectomy.

Central hepatectomy for perihilar cholangiocarcinoma: an alternative technique for parenchymal-sparing hepatectomy to prevent post-hepatectomy liver failure

BACKGROUND

Perihilar cholangiocarcinoma (PHC) often requires major hepatectomy with extrahepatic bile duct resection, carrying the risk of post-hepatectomy liver failure (PHLF). Central hepatectomy (CH), an alternative technique, aims to preserve functional liver reserve. This study evaluated the feasibility of CH and outcomes for patients with PHC within the paradigm of parenchymal-sparing hepatectomy.

METHODS

A retrospective analysis included PHC patients who underwent CH between March 2019 and January 2023. Preoperative evaluations involved multimodality imaging and assessment of future remnant liver volume.

RESULTS

Fourteen patients underwent CH for PHC. Tumor locations were perihilar bile duct (10 patients), and entire extrahepatic bile duct involvement (four patients). Median operative time and intraoperative blood loss were 679.5 min and 450 mL, respectively. Clinically-relevant PHLF occurred in two patients, with one sepsis-related death. Nine patients achieved R0 resection. Functional liver reserve parameters exceeded the standard procedure (p < 0.01).

CONCLUSION

CH for PHC preserves functional liver reserve, potentially reducing PHLF risk. Adequate preoperative evaluation is crucial, and oncological outcomes require further investigation.

Regional Liver Function Assessment Using 99mTc-GSA SPECT/CT Scintigraphy in Malignant Perihilar Biliary Tumor Undergoing Major Liver Resection: A Dual-Center Cohort Study

BACKGROUND

Cholestasis can lead to unreliable results of routine liver function assessment tests in clinical practice and the functional cutoff value of hepatectomy is still unclear. The aim of this study was to determine which 99mTc-GSA scintigraphy functional indicators can predict post-hepatectomy liver failure (PHLF) in patients before major liver resection due to malignant perihilar biliary disease. In addition, it aimed to assess the efficiency of functional future liver remnant (FLR) assessment of 99mTc-GSA scintigraphy indicators.

PATIENTS AND METHODS

A 99mTc-GSA scintigraphy was performed prior to planned surgery in 187 patients, including 81 patients with major liver resection. The 99mTc-GSA scintigraphy parameters including functional liver volume (FLV), ratio of the FLR functional volume to body weight (FLVFLR-BWR), and predictive residual index (PRI) were calculated from radioactive count in regions of FLR and total liver (TOTAL). Morphological liver volume (MLV) was calculated from computed tomography and standardized by standard liver volume (SLV). The efficacy of these parameters in predicting PHLF was compared using generalized linear mixed models and receiver operating characteristic (ROC) curve analysis.

RESULTS

PHLF occurred in 22 patients, who showed lower MLVFLR/SLV, FLVFLR, FLVFLR/FLVTOTAL, FLVFLR-BWR, and PRI and higher resection rate (P < 0.05 for all) than patients without PHLF. After adjusting for clinical parameters, a decreased FLVFLR-BWR (odds ratio, OR 0.17; 95% confidence intervals, CI 0.05-0.53) was found to be an independently significant indicator in the model of GLMM. FLVFLR-BWR (0.835) had the highest ROC among all liver functional indicators.

CONCLUSIONS

The FLR functional parameter preoperatively estimated from preoperative 99mTc-GSA scintigraphy protocol is a promising tool for regional liver function assessment, and it can distinguish high-risk patients who may develop PHLF with malignant perihilar biliary tumor undergoing major liver resection.

New criteria for preoperative liver function assessment with safety margins to avoid postoperative mortality during liver resection for hilar cholangiocarcinoma

BACKGROUND

Despite recent medical advancements, surgery for hilar cholangiocarcinoma is associated with high complication and mortality rates. This may be partly attributed to the absence of established preoperative liver evaluation criteria for safe surgery. This study aimed to propose a reliable indicator for safe and well-planned management of major hepatectomy with extrahepatic bile duct resection.

METHODS

We included 150 patients who underwent major hepatectomy with extrahepatic bile duct resection between 2013 and 2021 in Japan. The risk factors for post-hepatectomy liver failure (PHLF) were retrospectively analyzed.

RESULTS

PHLF was observed in 24 (16.0 %) patients who underwent major hepatectomy with extrahepatic bile duct resection. In the multivariate analysis, the identified risk factors for PHLF were the ratio of future remnant liver volume to total liver volume (FRLV/TLV) ≤ 42 % and indocyanine green clearance fraction of the future remnant liver (ICGK-F) ≤ 0.07. Patients with these two factors were significantly associated with PHLF compared with those with either one or none of the risk factors (60.0 % vs 15.1 % and 8.1 %, respectively).

CONCLUSION

The combinational use of ICGK-F and FRLV/TLV is useful for preoperative liver function assessment with a safety margin to avoid PHLF and postoperative mortality in hepatectomy for hilar cholangiocarcinoma.

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

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

Minimum proportion of future liver remnant in safe major hepatopancreatoduodenectomy

Background and Aim

Post-hepatectomy liver failure (PHLF) after major hepatopancreatoduodenectomy (HPD) is a challenge to overcome. However, the appropriate target proportion of the future liver remnant (pFLR) to prevent severe PHLF in major HPD remains uncertain. This study aimed to determine the minimum pFLR required for safe major HPD.

Methods

This retrospective study involved 48 major HPD patients. We assessed pFLR and remnant liver function scores (pFLR × albumin-bilirubin [ALBI] / albumin-indocyanine green evaluation [ALICE]/plasma clearance rate of indocyanine green [KICG]) as predictors for Grade B/C PHLF and established safety criteria.

Results

Grade B/C PHLF occurred in 40% of the patients (n = 19), leading to severe morbidity and two in-hospital deaths. pFLR was a good predictor of Grade B/C PHLF [area under the curve (AUC) 0.80, p < 0.01] with a 45% optimal cutoff. While all remnant liver function scores predicted PHLF, the remnant ALICE demonstrated the best predictability (AUC 0.85, p < 0.01), with the sensitivity and specificity at 89% and 83%, respectively, using -0.86 as the cutoff. Independent risk factors for Grade B/C PHLF were remnant ALICE ≥-0.86 and blood loss ≥1500 mL. Grade B/C PHLF developed in 14% with pFLR ≥45% but reached 64% with pFLR <45%. However, the rate could be reduced to 33% with remnant ALICE <-0.86.

Conclusion

To prevent Grade B/C PHLF, a pFLR ≥45% is recommended. Nevertheless, major HPD may be considered in patients with good remnant liver function.

Pattern and extent of intrahepatic infiltration of perihilar cholangiocarcinoma - a case-control study based on liver panoramic digital pathology

BACKGROUND

The extent of intrahepatic infiltration of perihilar cholangiocarcinoma (PHCC) remains unclear. This research aimed to explore the pattern and extent of intrahepatic infiltration of PHCC to guide surgical treatment and pathological research.

MATERIALS AND METHODS

This study included 62 patients diagnosed with PHCC who underwent major hepatectomy. A whole-mount digital liver pathology system (WDLPS) for hepatectomy specimens greater than 10×10 cm was used to panoramically assess the intrahepatic infiltration extent of PHCC.

RESULTS

The distal intrahepatic infiltration (DIHI) and radial liver invasion (RLI) were important parts of intrahepatic infiltration for PHCC explored by WDLPS. The study confirmed that 75.8% of PHCCs had RLI and the infiltration distance in all patients were within 15 000 µm, 62.9% of PHCCs had DIHI greater than 1 cm away from the main tumor in the liver parenchyma. The recurrence-free survival rates and overall survival rates of patients with DIHI were poorer than the patients without DIHI ( P <0.0001, P =0.0038). Arterial invasion on the resected side could be an excellent predictor. A total of 105 liver lobes were resected from 62 PHCC patients. The invasion rates of the left lateral, left medial, right anterior, and right posterior lobe of PHCC were 79%, 100%, 100%, and 69%, respectively.

CONCLUSION

The presence of DIHI in most PHCCs was a significant factor for the poor survival. Based on the extent of intrahepatic infiltration, minor hepatectomy was not suitable as the curative surgery for PHCC. Major hepatectomy and liver transplantation were the ideal radical treatment.

Liver Resection for Hepatocellular Carcinoma: Recent Advances

Hepatocellular carcinoma (HCC) represents a significant global health burden. Surgery remains a cornerstone in the curative treatment of HCC, and recent years have witnessed notable advancements aimed at refining surgical techniques and improving patient outcomes. This review presents a detailed examination of the recent innovations in HCC surgery, highlighting key developments in both surgical approaches and adjunctive therapies. Advanced imaging technologies have revolutionized preoperative assessment, enabling precise tumour localization and delineation of vascular anatomy. The use of three-dimensional rendering has significantly augmented surgical planning, facilitating more accurate and margin-free resections. The advent of laparoscopic and robotic-assisted surgical techniques has ushered in an era of minimal access surgery, offering patients the benefits of shorter hospital stays and faster recovery times, while enabling equivalent oncological outcomes. Intraoperative innovations such as intraoperative ultrasound (IOUS) and fluorescence-guided surgery have emerged as valuable adjuncts, allowing real-time assessment of tumour extent and aiding in parenchyma preservation. The integration of multimodal therapies, including neoadjuvant and adjuvant strategies, has allowed for 'bio-selection' and shown the potential to optimize patient outcomes. With the advent of augmented reality and artificial intelligence (AI), the future holds immense potential and may represent significant strides towards optimizing patient outcomes and refining the standard of care.

Predictability of combining Technetium-99m-galactosyl human serum albumin single-photon emission computed tomography/computed tomography and indocyanine green clearance test for posthepatectomy liver failure

PURPOSE

To evaluate the predictive ability of combining Technetium-99m-galactosyl human serum albumin (99mTc‑GSA) single-photon emission computed tomography (SPECT)/computed tomography (CT) volume and plasma clearance rate of indocyanine green (ICGK) for posthepatectomy liver failure (PHLF).

MATERIALS AND METHODS

Fifty patients who underwent 99mTc-GSA scintigraphy as a preoperative examination for segmentectomy or more from July 2021 to June 2023 were evaluated prospectively. Patients were divided into two groups according to the presence or absence of posthepatectomy liver failure (PHLF). Total functional liver volume (t-FLV) and remnant FLV (r-FLV) were measured from 99mTc-GSA SPECT/CT image. Future liver remnant ICGK (ICGK-F) was calculated by ICGK and remnant liver volume from CT. Area under the curve (AUC) of ICGK-F, r-FLV, r-FLV/t-FLV, ICGK × r-FLV, ICGK × r-FLV/t-FLV was calculated to evaluate predictive ability of each parameter for PHLF.

RESULTS

PHLF was occurred in 7 patients. AUC of ICGK × r-FLV was significantly higher than that of ICGK-F (0.99; 95% confidence interval [CI]: 0.96-1 vs 0.82; 95%CI: 0.64-0.96; p = 0.036). There was no significant difference between the AUC of r-FLV, r-FLV/t-FLV, ICGK × r-FLV/t-FLV and that of ICGK-F, respectively.

CONCLUSION

The combination of 99mTc‑GSA SPECT/CT volume and ICGK can predict PHLF more accurately than ICGK-F.

The impact of post-hepatectomy liver failure on long-term survival after liver resection for perihilar cholangiocarcinoma

BACKGROUND

Although post-hepatectomy liver failure (PHLF) can accurately predict short-term mortality of liver resection for perihilar cholangiocarcinoma (pCCA), its significance in predicting long-term overall survival (OS) is still uncertain.

METHODS

Retrospective analysis was performed on patients with pCCA who underwent liver resection between October 2013 and December 2018. The patients were divided into 3 groups; No PHF, PHLF (all grade) and grade B/C PHLF according to The International Study Group of Liver Surgery (ISGLS) criteria.

RESULTS

A total of 177 patients were enrolled, 65 (36.7%) had PHLF; 25 (14.1%) had grade A, and 40 (22.6%) had grade B/C. Prior to surgery, patients with PHLF showed significantly greater bilirubin levels and CA 19-9 level than those without (11.5 vs 6.7 mg/dL, p = 0.002 and 232.4 vs 85.9 U/mL, p = 0.005, respectively). Additionally, pre-operative future liver remnant volume in PHLF group was lower than no PHLF group significantly (39.6% vs 43.5%, p = 0.006). Major complication and 90-day mortality were higher in PHLF group than no PHLF group (69.2% vs 20.5%, p < 0.001 and 29.2% vs 3.6%, p < 0.001, respectively). The OS in both grade A PHLF and grade B/C PHLF was significantly worse compared to no PHLF, with median survival times of 8.4, 3.3, and 19.2 months, respectively (p < 0.001 and p < 0.001, respectively). Multivariable analysis revealed that PHLF was independently prognostic factor for long-term survival.

CONCLUSION

To achieve negative resection margin, the surgical resection in pCCA was aggressive, however this increased the risk of PHLF, which also affects the OS. Consequently, it is necessary for establishing a balance between aggressive surgery and PHLF.

Practice guidelines for managing extrahepatic biliary tract cancers

Backgrounds/Aims

Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021.

Methods

Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop.

Results

In November 2021, the finalized draft was presented for public scrutiny during a formal hearing.

Conclusions

The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

The link between high factor VIII to protein C ratio values and poor liver function after major hepatectomy

Our goal was to assess the coagulation profile in the immediate postoperative time after major liver surgery and its association with the liver function. Our hypothesis is that a decreased synthesis of the coagulation factor levels reflects an impaired liver synthesis following hepatic resection and will be associated with poor outcomes. This is a prospective, observational study recruiting consecutive patients scheduled for major liver resection in a tertiary hospital. Coagulation profile was assessed by conventional assays, viscoelastic assays and coagulation factor levels preoperatively and, on postoperative days 1, 2 and 6. Factor VIII to protein C (FVIII/PC) ratio has been used as a surrogate marker of hemostatic imbalance. Liver function was measured with conventional and indocyanine green (ICG) clearance tests, which were obtained preoperatively and on postoperative days 1 and 2. Sixty patients were recruited and 51 were included in the study. There is a clear increase in FVIII/PC ratio after surgery, which was significantly associated with low liver function, being more pronounced beyond postoperative day 2 and in patients with poorer liver function ( P  < 0.001). High FVIII/PC ratio values were significantly associated with higher postoperative morbidity, prolonged ICU and hospital stay and less survival ( P  < 0.05). High FVIII/PC ratio on postoperative day 2 was found to be predictor of posthepatectomy liver failure (PHLF; area under the ROC curve = 0.8129). Early postoperative high FVIII/PC ratio values are associated with low liver function, PHLF and poorer outcomes in patients undergoing major hepatic resection.

Albumin-indocyanine green evaluation of future liver remnant predicts liver failure after anatomical hepatectomy for hepatocellular carcinoma: A dual-center retrospective study

AIM

The albumin-indocyanine green evaluation (ALICE) score is a useful predictor of post-hepatectomy liver failure (PHLF); however, its usefulness in combination with future liver remnant (FLR), measured by 3-D volumetry, has not been investigated. This study aimed to investigate the relationship between the ALICE of the FLR (ALICE-FLR) score and severe PHLF.

METHODS

The clinical data of 215 patients who underwent anatomical hepatectomy for hepatocellular carcinoma without portal vein embolization at two institutes between January 2010 and December 2021 were analyzed retrospectively. PHLF occurrence and severity were determined according to the International Study Group of Liver Surgery's definition. Grades B and C PHLF were defined as severe PHLF. The ALICE-FLR, ALICE scores, and indocyanine green clearance of FLR (ICGK-FLR) were evaluated for severe PHLF prediction.

RESULTS

Severe PHLF was observed in 40 patients (18.6%). The areas under the curve (AUCs) for the ALICE-FLR, ALICE scores, ICGK-FLR, and FLR were 0.76, 0.64, 0.73, and 0.69, respectively. The AUC of the ALICE-FLR score was significantly higher than that of the ALICE score. The ALICE-FLR score was identified as an independent predictor of severe PHLF (the odds ratio for every 0.01 increment in the ALICE-FLR score was 1.24; 95% confidence interval, 1.070-1.453; p = 0.004). Among patients with severe PHLF, the ALICE-FLR score was significantly higher in the grade C than in the grade B PHLF group.

CONCLUSION

The combination of liver function models, including indocyanine green, albumin, and FLR is considered compatible for predicting severe PHLF.

Liver remnant volume to body weight ratio of 0.65% as a lower limit in right hepatic trisectionectomy with bile duct resection

BACKGROUND

Previous studies have suggested the utility of an indocyanine green plasma clearance rate of the future liver remnant (FLR) (ICGK-F) ≥0.05 in hepatobiliary resection to reduce the surgical risk. The present study aimed to verify whether future liver remnant size rather than ICGK-F matters in extended hepatobiliary resection.

METHODS

Between 2004 and 2021, patients who underwent right hepatic trisectionectomy with bile duct resection were included. The effect of the FLR volume-to-body weight ratio (FLR/BW) and ICGK-F on posthepatectomy liver failure was evaluated along with other parameters.

RESULTS

Among 91 study patients, the median ICGK-F, FLR, and FLR/BW were 0.057 (range, 0.027-0.099), 392 mL (145-705), and 0.78% (0.40-1.37), respectively. Posthepatectomy liver failure occurred in 23 patients. The incidence was 10 (40%) in 25 patients with an ICGK-F <0.05 and 12 (18%) in 65 patients with an ICGK-F ≥0.05 (P = .053); 13 (52%) in 25 patients with a FLR/BW <0.65% and 10 (15%) in 66 patients with a FLR/BW ≥0.65% (P = .001). Multivariate analysis showed that a FLR/BW <0.65% (odds ratio, 11.7; P = .005), age ≥65 years (odds ratio, 31.7; P < .001), and blood loss ≥25 mL/kg (odds ratio, 22.1; P = .004) were independent predictors of posthepatectomy liver failure, but ICGK-F <0.05 was not (P = .499). According to the meeting number of 3 factors, posthepatectomy liver failure incidence was 0 of 22 (0%) in patients with 0 factors, 6 of 43 (14%) in patients with 1, and 17 of 26 (65%) in patients with 2 or 3 (P < .001).

CONCLUSION

A FLR/BW ≥0.65% may serve as a volumetric basis to reduce posthepatectomy liver failure after extended hepatobiliary resection.

Recent advances in computerized imaging and its vital roles in liver disease diagnosis, preoperative planning, and interventional liver surgery: A review

The earliest and most accurate detection of the pathological manifestations of hepatic diseases ensures effective treatments and thus positive prognostic outcomes. In clinical settings, screening and determining the extent of a pathology are prominent factors in preparing remedial agents and administering appropriate therapeutic procedures. Moreover, in a patient undergoing liver resection, a realistic preoperative simulation of the subject-specific anatomy and physiology also plays a vital part in conducting initial assessments, making surgical decisions during the procedure, and anticipating postoperative results. Conventionally, various medical imaging modalities, e.g., computed tomography, magnetic resonance imaging, and positron emission tomography, have been employed to assist in these tasks. In fact, several standardized procedures, such as lesion detection and liver segmentation, are also incorporated into prominent commercial software packages. Thus far, most integrated software as a medical device typically involves tedious interactions from the physician, such as manual delineation and empirical adjustments, as per a given patient. With the rapid progress in digital health approaches, especially medical image analysis, a wide range of computer algorithms have been proposed to facilitate those procedures. They include pattern recognition of a liver, its periphery, and lesion, as well as pre- and postoperative simulations. Prior to clinical adoption, however, software must conform to regulatory requirements set by the governing agency, for instance, valid clinical association and analytical and clinical validation. Therefore, this paper provides a detailed account and discussion of the state-of-the-art methods for liver image analyses, visualization, and simulation in the literature. Emphasis is placed upon their concepts, algorithmic classifications, merits, limitations, clinical considerations, and future research trends.

Essential updates 2021/2022: Update in surgical strategy for perihilar cholangiocarcinoma

Resection is the only potential curative treatment for perihilar cholangiocarcinoma (PHC); however, complete resection is often technically challenging due to the anatomical location. Various innovative approaches and procedures were invented to circumvent this limitation but the rates of postoperative morbidity (20%-78%) and mortality (2%-15%) are still high. In patients diagnosed with resectable PHC, deliberate and coordinated preoperative workup and optimization of the patient and future liver remnant are crucial. Biliary drainage is recommended to relieve obstructive jaundice and optimize the clinical condition before liver resection. Biliary drainage for PHC can be performed either by endoscopic biliary drainage or percutaneous transhepatic biliary drainage. To date there is no consensus about which method is preferred. The volumetric assessment of the future remnant liver volume and optimization mainly using portal vein embolization is the gold standard in the management of the risk to develop post hepatectomy liver failure. The improvement of systemic chemotherapy has contributed to prolong the survival not only in patients with unresectable PHC but also in patients undergoing curative surgery. In this article, we review the literature and discuss the current surgical treatment of PHC.

Liver functional assessment using time-associated change in the liver-to-spleen signal intensity ratio on enhanced magnetic resonance imaging: a retrospective study

BACKGROUND

Liver-to-spleen signal intensity ratio (LSR) is evaluated by magnetic resonance imaging (MRI) in the hepatobiliary phase and has been reported as a useful radiological assessment of regional liver function. However, LSR is a passive (non-time-associated) assessment of liver function, not a dynamic (time-associated) assessment. Moreover, LSR shows limitations such as a dose bias of contrast medium and a timing bias of imaging. Previous studies have reported the advantages of time-associated liver functional assessment as a precise assessment of liver function. For instance, the indocyanine green (ICG) disappearance rate, which is calculated from serum ICG concentrations at multiple time points, reflects a precise preoperative liver function for predicting post-hepatectomy liver failure without the dose bias of ICG or the timing bias of blood sampling. The aim of this study was to develop a novel time-associated radiological liver functional assessment and verify its correlation with traditional liver functional parameters.

METHODS

A total of 279 pancreatic cancer patients were evaluated to clarify fundamental time-associated changes to LSR in normal liver. We defined the time-associated radiological assessment of liver function, calculated using information on LSR from four time points, as the "LSR increasing rate" (LSRi). We then investigated correlations between LSRi and previous liver functional parameters. Furthermore, we evaluated how timing bias and protocol bias affect LSRi.

RESULTS

Significant correlations were observed between LSRi and previous liver functional parameters such as total bilirubin, Child-Pugh grade, and albumin-bilirubin grade (P < 0.001 each). Moreover, considerably high correlations were observed between LSRi calculated using four time points and that calculated using three time points (r > 0.973 each), indicating that the timing bias of imaging was minimal.

CONCLUSIONS

This study propose a novel time-associated radiological assessment, and revealed that the LSRi correlated significantly with traditional liver functional parameters. Changes in LSR over time may provide a superior preoperative assessment of regional liver function that is better for predicting post-hepatectomy liver failure than LSR using the hepatobiliary phase alone.

Risk factors for postoperative pneumonia after hepatectomy with extrahepatic bile duct resection

BACKGROUND

The present study investigated the incidence of postoperative pneumonia (POP) after hepatectomy with extrahepatic bile duct resection (BDR) and elucidated risk factors for POP.

METHODS

A total of 257 patients undergoing hepatectomy with BDR between 2011 and 2019 were retrospectively reviewed to evaluate the incidence of POP, defined by the Clavien-Dindo grade ≥ II. The predictive factors for POP were identified using logistic regression analysis of the pre- and intraoperative evaluable factors.

RESULTS

Postoperative pneumonia developed in 15 patients (5.8%), diagnosed as grade IV or V in five patients. In a multivariate analysis, a vital capacity ratio (%VC) <80% (odds ratio [OR] 7.30, P = .005), age ≥ 74 years old (OR 5.39, P = .026), and future liver volume remnant (FLR) ratio ≤ 40% (OR 4.97, P = .045) were independent risk factors for POP. Among patients with performing spirometry, the incidence of developing POP was 1.0%, 8.8%, and 60% in patients with 0, 1-2, and 3 risk factors, respectively.

CONCLUSIONS

The incidence of POP in patients undergoing hepatectomy with BDR was 5.8%. A %VC <80%, age ≥74 years old, and FLR ratio ≤40% were identified as preoperative predictive factors of developing POP.

Impact of preoperative muscle mass and quality on surgical outcomes in patients undergoing major hepatectomy for perihilar cholangiocarcinoma

PURPOSES

This study sought to define the impact of skeletal muscle mass and quality on postoperative outcomes in patients with perihilar cholangiocarcinoma.

METHODS

Patients who underwent major hepatectomy for perihilar cholangiocarcinoma were included. The normalized total psoas area (TPA) (psoas muscle index [PMI]) and average Hounsfield units of the TPA (psoas muscle density [PMD]) were measured using preoperative computed tomography images. The cohort was dichotomized using the following indices: sex-specific lowest tertile (low PMI and low PMD) and other (normal PMI and normal PMD). Intraoperative and postoperative outcomes were compared, focusing on PMI and PMD.

RESULTS

A total of 456 patients were analyzed. The intraoperative blood loss (IBL) was 21.3 ml/kg in the low PMI group and 17.2 ml/kg in the normal PMI group (P = .008). Patients in the low PMI or PMD group experienced postoperative infectious complications more frequently than those in the other groups. The median survival time was 37.8 months in the low PMI group and 54.2 months in the normal PMI group (P = .027).

CONCLUSIONS

PMI and PMD were closely associated with IBL and postoperative infectious complications. Additionally, PMI impacted long-term survival. These results suggest an importance of improving muscle mass and quality before surgery.

Preoperative indocyanine green (ICG) clearance test: Can we really trust it to predict post hepatectomy liver failure? A systematic review of the literature and meta-analysis of diagnostic test accuracy

INTRODUCTION

Post hepatectomy liver failure (PHFL) still represents a potentially fatal complication after major liver resection. Indocyanine green (ICG) clearance test represents one of the most widely adopted examinations in the preoperative workup. Despite a copious body of evidence which has been published on this topic, the role of ICG in predicting PHLF is still a matter of debate.

METHODS

A systematic review of the literature was conducted according to PRISMA-DTA guidelines. The primary outcome was the assessment of diagnostic performance of ICG in predicting PHLF. The secondary outcome was the mean ICG_R15 and ICG_PDR in patients experiencing PHLF.

RESULTS

Seventeen studies, for a total of 4852 patients, were deemed eligible. Sensitivity ranged from 25% to 83%; Specificity ranged from 66.1% to 93.8%. ICG clearance test pooled AUC was 0.673 (95% CI: 0.632-0.713). The weighted mean ICG_R15 was 11 (95%CI: 8.3-13.7). The weighted mean ICG_PDR was 16.5 (95%CI: 13.3-19.8). High risk of bias was detected in all examined domains.

CONCLUSIONS

Preoperative ICG clearance test alone may not represent a reliable method to predict post hepatectomy liver failure. Its diagnostic significance should be framed within multiparametric models involving clinical and imaging features.

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.

Converted-hepatopancreatoduodenectomy for an intraoperative positive ductal margin after pancreatoduodenectomy in distal cholangiocarcinoma

PURPOSE

Pancreatoduodenectomy (PD) is the standard treatment for distal cholangiocarcinoma, and a negative ductal margin (DM0) is indispensable for the long-term survival. When intraoperative frozen sections of ductal margin after PD are positive, converted-hepatopancreatoduodenectomy (C-HPD) is the final option available to gain an additional ductal margin. However, the efficacy of C-HPD remains unclear.

METHODS

Patients who underwent PD or C-HPD for distal cholangiocarcinoma between 2002 and 2019 were analyzed. The type of hepatectomy in C-HPD was restricted to left hepatectomy to prevent posthepatectomy liver failure.

RESULTS

Of 203 patients who underwent PD for distal cholangiocarcinoma, 49 patients exhibited intraoperative positive ductal margin (DM1) after PD. Eleven patients underwent C-HPD for intraoperative DM1 after PD, in which intraoperative DM1 with invasive carcinoma (DM1inv) was observed in 3 patients, and intraoperative DM1 with carcinoma in situ (DM1cis) was observed in 8 patients. The median additional ductal margin yielded by C-HPD was 9 mm (interquartile range 7-13 mm). C-HPD eradicated intraoperative DM1inv in 3 patients, with 2 patients showing DM0 and 1 patient showing DM1cis. Regarding 8 patients who underwent C-HPD for intraoperative DM1cis, 4 patients had DM0, but the others had DM1cis. C-HPD was associated with a high complication rate, but no mortality was observed. The median survival time of patients who underwent C-HPD was 48.8 months.

CONCLUSION

C-HPD was able to safely eradicate intraoperative DM1inv after PD. However, the length of the resected bile duct according to C-HPD may not be sufficient to remove intraoperative DM1cis after PD.

Validation study of postoperative liver failure and mortality risk scores after liver resection for perihilar cholangiocarcinoma

BACKGROUND

Surgery for perihilar cholangiocarcinoma (PHCC) remains a challenging procedure with high morbidity and mortality. The Academic Medical Center (Amsterdam UMC) and Memorial Sloan Kettering Cancer Center proposed a postoperative mortality risk score (POMRS) and post-hepatectomy liver failure score (PHLFS) to predict patient outcomes. This study aimed to validate the POMRS and PHLFS for PHCC patients at Hokkaido University.

METHODS

Medical records of 260 consecutive PHCC patients who had undergone major hepatectomy with extrahepatic bile duct resection without pancreaticoduodenectomy at Hokkaido University between March 2001 and November 2018 were evaluated to validate the PHLFS and POMRS.

RESULTS

The observed risks for PHLF were 13.7%, 24.5%, and 39.8% for the low-risk, intermediate-risk, and high-risk groups, respectively, in the study cohort. A receiver-operator characteristic (ROC) analysis revealed that the PHLFS had moderate predictive value, with an analysis under the curve (AUC) value of 0.62. Mortality rates based on the POMRS were 1.7%, 5%, and 5.1% for the low-risk, intermediate-risk, and high-risk groups, respectively. The ROC analysis demonstrated an AUC value of 0.58.

CONCLUSIONS

This external validation study showed that for PHLFS the threshold for discrimination in an Eastern cohort was reached (AUC >0.6), but it would require optimization of the model before use in clinical practice is acceptable. The POMRS were not applicable in the eastern cohort. Further external validation is recommended.

Risk Prediction Model Based on Magnetic Resonance Elastography-Assessed Liver Stiffness for Predicting Posthepatectomy Liver Failure in Patients with Hepatocellular Carcinoma

Background/Aims

Posthepatectomy liver failure (PHLF) is a major complication that increases mortality in patients with hepatocellular carcinoma after surgical resection. The aim of this retrospective study was to evaluate the utility of magnetic resonance elastography-assessed liver stiffness (MRE-LS) for the prediction of PHLF and to develop an MRE-LS-based risk prediction model.

Methods

A total of 160 hepatocellular carcinoma patients who underwent surgical resection with available preoperative MRE-LS data were enrolled. Clinical and laboratory parameters were collected from medical records. Logistic regression analyses were conducted to identify the risk factors for PHLF and develop a risk prediction model.

Results

PHLF was present in 24 patients (15%). In the multivariate logistic analysis, high MRE-LS (kPa; odds ratio [OR] 1.49, 95% confidence interval [CI] 1.12 to 1.98, p=0.006), low serum albumin (≤3.8 g/dL; OR 15.89, 95% CI 2.41 to 104.82, p=0.004), major hepatic resection (OR 4.16, 95% CI 1.40 to 12.38, p=0.014), higher albumin-bilirubin score (>-0.55; OR 3.72, 95% CI 1.15 to 12.04, p=0.028), and higher serum α-fetoprotein (>100 ng/mL; OR 3.53, 95% CI 1.20 to 10.40, p=0.022) were identified as independent risk factors for PHLF. A risk prediction model for PHLF was established using the multivariate logistic regression equation. The area under the receiver operating characteristic curve (AUC) of the risk prediction model was 0.877 for predicting PHLF and 0.923 for predicting grade B and C PHLF. In leave-one-out cross-validation, the risk model showed good performance, with AUCs of 0.807 for all-grade PHLF and 0. 871 for grade B and C PHLF.

Conclusions

Our novel MRE-LS-based risk model had excellent performance in predicting PHLF, especially grade B and C PHLF.

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

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

Hepatectomy risk assessment with functional magnetic resonance imaging (HEPARIM)

Background

Post hepatectomy liver failure (PHLF) remains a significant risk in patients undergoing curative liver resection for cancer, however currently available PHLF risk prediction investigations are not sufficiently accurate.

The Hepatectomy risk assessment with functional magnetic resonance imaging trial (HEPARIM) aims to establish if quantitative MRI biomarkers of liver function & perfusion can be used to more accurately predict PHLF risk and FLR function, measured against indocyanine green (ICG) liver function test.

Methods

HEPARIM is an observational cohort study recruiting patients undergoing liver resection of 2 segments or more, prior to surgery patients will have both Dynamic Gadoxetate-enhanced (DGE) liver MRI and ICG testing.

Day one post op ICG testing is repeated and R15 compared to the Gadoxetate Clearance (GC) of the future liver remnant (FLR-GC) as measure by preoperative DGE- MRI which is the primary outcome, and preoperative ICG R15 compared to GC of whole liver (WL-GC) as a secondary outcome.

Data will be collected from medical records, biochemistry, pathology and radiology reports and used in a multi-variate analysis to the value of functional MRI and derive multivariant prediction models for future validation.

Discussion

If successful, this test will potentially provide an efficient means to quantitatively assess FLR function and PHLF risk enabling surgeons to push boundaries of liver surgery further while maintaining safe practice and thereby offering chance of cure to patients who would previously been deemed inoperable. MRI has the added benefit of already being part of the routine diagnostic pathway and as such would have limited additional burden on patients time or cost to health care systems. (Hepatectomy Risk Assessment With Functional Magnetic Resonance Imaging - Full Text View -ClinicalTrials.gov, n.d.)

Trial registration

ClinicalTrials.gov, ClinicalTrials.gov NCT04705194 - Registered 12th January 2021 – Retrospectively registered

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08830-4.

A systematic review of prediction models for post-hepatectomy liver failure in patients undergoing liver surgery

BACKGROUND

The aim of this systematic review is to evaluate the current evidence in the context of clinical prediction model for post-hepatectomy liver failure (PHLF).

METHODS

A systematic search of the English literature for a period from December 2005 to September 2020 was conducted. Primary outcome was defined using the three common PHLF criteria (50-50 criteria, peak bilirubin>7 mg/dl criteria, and ≥ grade B PHLF criteria by the International Study Group of Liver Surgery). Studies that reported the value of area under receiver operative characteristic curve (AUC) for the occurrence of PHLF were included.

RESULTS

Twenty eight of 1327 screened articles were eligible for inclusion. Eighteen studies developed the prediction models. The median AUC was found to be 0.79 (0.65-0.933). The parameters related to the amount of future liver remnant volume were most commonly identified as significant predictors for PHLF in statistical analysis (24 studies) and were most frequently incorporated in the prediction models (18 studies). The parameters associated with portal hypertension were significant for predicting PHLF in 16 studies and were adopted in the prediction models in 14 studies.

CONCLUSION

Parameters related to future liver remnant volume and portal hypertension seem to be facilitating in predicting PHLF.

Hepatocellular uptake index obtained with gadoxetate disodium-enhanced magnetic resonance imaging in the assessment future liver remnant function after major hepatectomy for biliary malignancy

Background

Functional assessment of the future liver remnant (FLR) after major hepatectomy is essential but often difficult in patients with biliary malignancy, owing to obstructive jaundice and portal vein embolization. This study evaluated whether a novel index using gadoxetate disodium-enhanced MRI (EOB-MRI) could predict posthepatectomy liver failure (PHLF) after major hepatectomy for biliary malignancy.

Methods

The remnant hepatocellular uptake index (rHUI) was calculated in patients undergoing EOB-MRI before major hepatectomy for biliary malignancy. Receiver operating characteristic (ROC) curve analyses were used to evaluate the accuracy of rHUI for predicting PHLF grade B or C, according to International Study Group of Liver Surgery criteria. Multivariable logistic regression analyses comprised stepwise selection of parameters, including rHUI and other conventional indices.

Results

This study included 67 patients. The rHUI accurately predicted PHLF (area under the curve (AUC) 0.896). A cut-off value for rHUI of less than 0.410 predicted all patients who developed grade B or C PHLF. In multivariable analysis, only rHUI was an independent risk factor for grade B or C PHLF (odds ratio 2.0 × 10³, 95 per cent c.i. 19.6 to 3.8 × 10⁷; P < 0.001). In patients who underwent preoperative portal vein embolization, rHUI accurately predicted PHLF (AUC 0.885), whereas other conventional indices, such as the plasma disappearance rate of indocyanine green of the FLR and FLR volume, did not.

Conclusion

The rHUI is potentially a useful predictor of PHLF after major hepatectomy for biliary malignancy.

Utility of remnant liver volume for predicting posthepatectomy liver failure after hepatectomy with extrahepatic bile duct resection

BACKGROUND

Hepatectomy with extrahepatic bile duct resection is associated with a high risk of posthepatectomy liver failure (PHLF). However, the utility of the remnant liver volume (RLV) in cholangiocarcinoma has not been studied intensively.

METHODS

Patients who underwent major hepatectomy with extrahepatic bile duct resection between 2002 and 2018 were reviewed. The RLV was divided by body surface area (BSA) to normalize individual physical differences. Risk factors for clinically relevant PHLF were evaluated with special reference to the RLV/BSA.

RESULTS

A total of 289 patients were included. The optimal cut-off value for RLV/BSA was determined to be 300 ml/m2. Thirty-two patients (11.1 per cent) developed PHLF. PHLF was more frequent in patients with an RLV/BSA below 300 ml/m2 than in those with a value of 300 ml/m2 or greater: 19 of 87 (22 per cent) versus 13 of 202 (6.4 per cent) (P < 0.001). In multivariable analysis, RLV/BSA below 300 ml/m2 (P = 0.013), future liver remnant plasma clearance rate of indocyanine green less than 0.075 (P = 0.031), and serum albumin level below 3.5 g/dl (P = 0.015) were identified as independent risk factors for PHLF. Based on these risk factors, patients were classified into three subgroups with low (no factors), moderate (1-2 factors), and high (3 factors) risk of PHLF, with PHLF rates of 1.8, 14.8 and 63 per cent respectively (P < 0.001).

CONCLUSION

An RLV/BSA of 300 ml/m2 is a simple predictor of PHLF in patients undergoing hepatectomy with extrahepatic bile duct resection.

Regional liver function analysis with gadoxetic acid-enhanced MRI and virtual hepatectomy: prediction of postoperative short-term outcomes for HCC

OBJECTIVES

To explore the role of quantitative regional liver function assessed by preoperative gadoxetic acid-enhanced MRI with computer-aided virtual hepatectomy to predict short-term outcomes after major hepatectomy for HCC.

METHODS

We retrospectively reviewed the records of 133 consecutive patients with HCC who underwent preoperative gadoxetic acid-enhanced MRI and indocyanine green (ICG) test. Forty-five patients received open major hepatectomy. Liver function reserve and the future liver remnant were evaluated by computer-aided virtual hepatectomy. Global liver functional parameters included the T1 relaxation time reduction rate (T1_ratio) and functional liver volume (FV), whereas regional parameters included the rT1_pos, rT1_ratio, remnant FV (rFV), and remnant FV ratio (rFV_ratio) of the remnant liver. The functional parameters of the MRI and ICG were used to predict the short-term outcomes (liver failure and major complications) after major hepatectomy.

RESULTS

The T1_ratio and FV were correlated with the ICG test (rho = - 0.304 and - 0.449, p < 0.05). FV < 682.8 ml indicated preoperative ICG-_R15 ≥ 14% with 0.765 value of the area under the curve (AUC). No patient who underwent major resection with good liver functional reserve (ICG < 14%) and enough future remnant volume (> 30% standard LV) developed liver failure. Low rT1_ratio (< 66.5%) and high rT1_pos (> 217.5 ms) may predict major complications (AUC = 0.831 and 0.756, respectively; p < 0.05). The rT1_ratio was an independent risk factor for postoperative major complications (odds ratio [OR] = 0.845, 95% CI, 0.736-0.966; p < 0.05).

CONCLUSION

Preoperative gadoxetic acid-enhanced MRI with computer-aided virtual hepatectomy may facilitate optimal assessment of regional liver functional reserve to predict short-term outcomes after major hepatectomy for HCC.

KEY POINTS

• Preoperative gadoxetic acid-enhanced MRI with virtual hepatectomy and volumetric analysis can provide precise liver volume and regional functional assessment. • Quantitative regional liver function assessed by gadoxetic acid-enhanced MRI can predict the short-term outcomes after major hepatectomy in patients with HCC. • The regional liver function assessed by gadoxetic acid-enhanced MRI is an independent risk factor for postoperative major complications.

Clinical practice guidelines for the management of biliary tract cancers 2019: The 3rd English edition

BACKGROUND

The Japanese Society of Hepato-Biliary-Pancreatic Surgery launched the clinical practice guidelines for the management of biliary tract cancers (cholangiocarcinoma, gallbladder cancer, and ampullary cancer) in 2007, then published the 2nd version in 2014.

METHODS

In this 3rd version, clinical questions (CQs) were proposed on six topics. The recommendation, grade for recommendation, and statement for each CQ were discussed and finalized by an evidence-based approach. Recommendations were graded as Grade 1 (strong) or Grade 2 (weak) according to the concepts of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system.

RESULTS

The 31 CQs covered the six topics: (a) prophylactic treatment, (b) diagnosis, (c) biliary drainage, (d) surgical treatment, (e) chemotherapy, and (f) radiation therapy. In the 31 CQs, 14 recommendations were rated strong and 14 recommendations weak. The remaining three CQs had no recommendation. Each CQ includes a statement of how the recommendations were graded.

CONCLUSIONS

This latest guideline provides recommendations for important clinical aspects based on evidence. Future collaboration with the cancer registry will be key for assessing the guidelines and establishing new evidence.

Safety and Oncological Benefit of Hepatopancreatoduodenectomy for Advanced Extrahepatic Cholangiocarcinoma with Horizontal Tumor Spread: Shinshu University Experience

BACKGROUND

Although hepatopancreatoduodenectomy (HPD) is the only means of achieving R0 resection of widespread extrahepatic cholangiocarcinoma, its safety and oncological benefit remain controversial because of its inherent high risk of mortality and morbidity.

OBJECTIVE

The aim of this study was to retrospectively analyze short- and long-term outcomes and evaluate the safety and oncological benefit of this advanced procedure.

METHODS

The study cohort comprised 37 consecutive patients who had undergone major HPD. Portal vein embolization was performed before surgery in 20 (54%) patients with future remnant liver volume < 35%.

RESULTS

The median operative time and blood loss were 866 min and 1000 mL, respectively. Concomitant vascular resection was performed in five patients (14%). The overall morbidity and mortality rates were 100% and 5.4% (n = 2), respectively. Nineteen patients (51%) had major (Clavien-Dindo grade III or higher) complications, the most common being intra-abdominal infection (49%) and post-hepatectomy liver failure (46%, grade B/C: 32%/5%), followed by postoperative pancreatic fistula (30%, grade B/C). R0 resection was achieved in 31 patients (84%). The 1-, 3-, and 5-year overall survival (OS) rates were 83%, 48%, and 37%, respectively. In patients with R0 resection, 5-year OS was comparable between patients who had undergone major HPD and major hepatectomy alone (41% vs. 40%, p = non-significant).

CONCLUSIONS

HPD is a valid treatment option for extensive cholangiocarcinoma, offering long-term survival benefit at the cost of relatively high but acceptable morbidity and mortality rates. HPD is advocated in selected patients provided that it is considered possible to achieve R0 resection.

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.

Combined Vascular Resection for Locally Advanced Perihilar Cholangiocarcinoma

OBJECTIVE

To evaluate the efficacy and safety of combined vascular resection (VR) in advanced perihilar cholangiocarcinoma (PHC).

SUMMARY OF BACKGROUND DATA

Hepatectomy combined with portal vein resection (PVR) and/or hepatic artery resection (HAR) is technically demanding but an option only for tumor eradication against PHC involving the hilar hepatic inflow vessels; however, its efficacy and safety have not been well evaluated.

METHODS

Patients diagnosed with PHC during 2001-2018 were included. Patients who underwent resection were divided according to combined VR. Patients undergoing VR were subdivided according to type of VR. Postoperative outcomes and OS were compared between patient groups.

RESULTS

Among the 1055 consecutive patients, 787 (75%) underwent resection (without VR: n = 484, PVR: n = 157, HAR: n = 146). The incidences of postoperative complications and mortality were 49% (without VR vs with VR, 48% vs 50%; P= 0.715) and 2.1% (without VR vs with VR, 1.2% vs 3.6%; P= 0.040), respectively. The OS of patients who underwent resection with VR (median, 30 months) was shorter than that of those who underwent resection without VR (median, 61 months; P < 0.0001); however, it was longer than that of those who did not undergo resection (median, 10 months; P < 0.0001). OS was not significantly different between those who underwent PVR and those who underwent HAR (median, 29 months vs 34 months; P = 0.517).

CONCLUSION

VR salvages a large number of patients from having locally advanced PHC that is otherwise unresectable and is recommended if the hilar hepatic inflow vessels are reconstructable, providing acceptable surgical outcomes and substantial survival benefits.

Issues to be considered to address the future liver remnant prior to major hepatectomy

An accurate preoperative evaluation of the hepatic function and application of portal vein embolization in selected patients have helped improve the safety of major hepatectomy. In planning major hepatectomy, however, several issues remain to be addressed. The first is which cut-off values for serum total bilirubin level and prothrombin time should be used to define post-hepatectomy liver failure. Other issues include what minimum future liver remnant (FLR) volume is required; whether the total liver volume measured using computed tomography or the standard liver volume calculated based on the body surface area should be used to assess the adequacy of the FLR volume; whether there is a discrepancy between the FLR volume and function during the recovery period after portal vein embolization or hepatectomy; and how best the function of a specific FLR can be assessed. Various studies concerning these issues have been reported with controversial results. We should also be aware that different strategies and management are required for different types of liver damage, such as cirrhosis in hepatocellular carcinoma, cholangitis in biliary tract cancer, and chemotherapy-induced hepatic injury.

Hepatic function assessment to predict post-hepatectomy liver failure: what can we trust? A systematic review

Post hepatectomy liver failure (PHLF) could occur even though an adequate liver volume is preserved. Liver function is not strictly related to the volume and the necessity to pre-operatively predict the future liver remnant (FLR) function is emerging, together with the wide spreading of techniques, aiming to optimize the FLR. The aim of this study was to systematically review all the available tests, to pre-operatively assess the liver function and to estimate the risk of PHLF. A systematic literature research of Medline, Embase, Scopus was performed in accordance to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, to identify all the studies available for pre-operative liver function tests to assess the risk of PHLF and/or complications. From the 1122 references retrieved, 79 were included in the review. Dynamic functional tests, such as indocyanine green test (ICG), could evaluate only global liver function, with no definition of functional capacity of the remnant. Magnetic resonance imaging (MRI) with liver-specific contrast agents enables both liver function and volume evaluation; the absence of ionizing radiation showed a better patient's compliance. Nuclear imaging studies as hepatobiliary scintigraphy (HBS) present the unique ability to allow a precise evaluation of the segmental liver function of the remnant liver. Liver volume could overestimate liver function. Several liver function tests are available to evaluate the risk of PHLF in the pre-operative setting. However, no single test alone could accurately predict PHLF. Pre-operative combination between a dynamic quantitative test, such as ICG, with MRI or HBS, should enable a more complete functional evaluation. Functional tests to predict PHLF should be chosen according to patient's characteristics, disease, and center experience.

Portal Vein Embolization is Associated with Reduced Liver Failure and Mortality in High-Risk Resections for Perihilar Cholangiocarcinoma

BACKGROUND

Preoperative portal vein embolization (PVE) is frequently used to improve future liver remnant volume (FLRV) and to reduce the risk of liver failure after major liver resection.

OBJECTIVE

This paper aimed to assess postoperative outcomes after PVE and resection for suspected perihilar cholangiocarcinoma (PHC) in an international, multicentric cohort.

METHODS

Patients undergoing resection for suspected PHC across 20 centers worldwide, from the year 2000, were included. Liver failure, biliary leakage, and hemorrhage were classified according to the respective International Study Group of Liver Surgery criteria. Using propensity scoring, two equal cohorts were generated using matching parameters, i.e. age, sex, American Society of Anesthesiologists classification, jaundice, type of biliary drainage, baseline FLRV, resection type, and portal vein resection.

RESULTS

A total of 1667 patients were treated for suspected PHC during the study period. In 298 patients who underwent preoperative PVE, the overall incidence of liver failure and 90-day mortality was 27% and 18%, respectively, as opposed to 14% and 12%, respectively, in patients without PVE (p < 0.001 and p = 0.005). After propensity score matching, 98 patients were enrolled in each cohort, resulting in similar baseline and operative characteristics. Liver failure was lower in the PVE group (8% vs. 36%, p < 0.001), as was biliary leakage (10% vs. 35%, p < 0.01), intra-abdominal abscesses (19% vs. 34%, p = 0.01), and 90-day mortality (7% vs. 18%, p = 0.03).

CONCLUSION

PVE before major liver resection for PHC is associated with a lower incidence of liver failure, biliary leakage, abscess formation, and mortality. These results demonstrate the importance of PVE as an integral component in the surgical treatment of PHC.

Level of total bilirubin in the bile of the future remnant liver of patients with obstructive jaundice undergoing hepatectomy predicts postoperative liver failure

BACKGROUND

We investigated whether the daily level of total bilirubin in the bile (LTB) excreted from the future remnant liver (FRL) can predict post-hepatectomy liver failure (PHLF) in patients with obstructive jaundice undergoing hepatectomy.

METHODS

Seventy-four patients who underwent biliary drainage and collection of bile juice from the FRL before undergoing right hepatectomy or right/left trisectionectomy with bile duct resection were included. The LTB from the FRL (mg/d) was calculated as the volume of the bile (dL) per day multiplied by the density of total bilirubin in the bile (mg/dL). We compared patients' characteristics with or without PHLF, which was defined as the total serum bilirubin level remaining >10 mg/dL after postoperative day 10. Then, pre- and intraoperative factors related to PHLF were examined.

RESULTS

PHLF was observed in six patients. LTB was significantly lower in the PHLF group. The LTB cut-off value for predicting PHLF, as determined using the receiver operating characteristic curve, was 56 mg/d. On multivariate analysis, LTB was found to be an independent risk factor for PHLF (P = .01, OR 35.88).

CONCLUSIONS

LTB may be a potential functional assessment in jaundiced patients before right hepatectomy and right/left trisectionectomy.

Predictive factors for liver volume and function recovery after resection using three-dimensional analysis

BACKGROUND

Clinical and biological factors that predict liver volume recovery rate (LVRR) after liver resection of different resected volume (RV) have not been studied extensively. Moreover, it remains uncertain whether remnant liver volume influences the liver function recovery rate (LFRR). This study examined the predictive factors for LVRR after liver resections of different RV and investigated LFRR by focusing on LVRR improvements after hepatectomy.

METHODS

Patients who underwent hepatectomy between January 2013 and August 2015 were reviewed retrospectively. LVRR and LFRR were assessed at postoperative months (POMs) 3, 6, and 12. LVRR was evaluated on the basis of RV (0%-15%, 15%-30%, 30%-45%, and >45%). LFRR was evaluated using total bilirubin, prothrombin time, and platelet count.

RESULTS

LVRR was lower with more extensive liver resections. Significant independent predictors of LVRR were type IV collagen 7s domain levels and resection magnitude. Platelet count correlated positively with LVRR at all POMs.

CONCLUSIONS

Resected livers regenerated after surgery but did not reach preoperative volumes. Preserving the liver as much as possible during resection can result in greater LFRR after hepatectomy. Therefore, decisions regarding liver resection volume should be made very carefully, particularly in patients with higher type IV collagen 7s domain levels.

Risk factors of posthepatectomy liver failure for perihilar cholangiocarcinoma: Risk score and significance of future liver remnant volume-to-body weight ratio

BACKGROUND

Surgery for perihilar cholangiocarcinoma (PHCC) is associated with high morbidity. This study aimed to investigate the clinical value of the future liver remnant volume-to-body weight (FLRV/BW) and propose a risk score for predicting the risk of patients with PHCC developing posthepatectomy liver failure (PHLF).

METHODS

This study included 348 patients who underwent major hepatectomy with bile duct resection for PHCC during 2008-2015 at a single center in Korea and they were retrospectively analyzed.

RESULTS

Clinically relevant PHLF was noted in 40 patients (11.4%). The area under the curve (AUC) for FLRV/BW was not significantly different from that for FLRV/total liver volume (P = .803) or indocyanine green clearance of the future liver remnant (P = .629) in terms of predicting PHLF. On multivariate analysis, predictors of PHLF (P < .05) were male sex, albumin less than 3.5 g/dL, preoperative cholangitis, portal vein resection, FLRV/BW less than 0.5%, and FLRV/BW 0.5% to 0.75%. These variables were included in the risk score that showed good discrimination (AUC, 0.853; 95% CI, 0.802-0.904). It will help rank patients into three risk subgroups with a predicted liver failure incidence of 4.75%, 18.73%, and 51.58%, respectively.

CONCLUSIONS

FLRV/BW is a comparable risk prediction factor of PHLF and the proposed risk score can help to predict the risk of planned surgery in PHCC.

Effect of structured use of preoperative portal vein embolization on outcomes after liver resection of perihilar cholangiocarcinoma

Background

Portal vein embolization (PVE) is performed to reduce the risk of liver failure and subsequent mortality after major liver resection. Although a cut‐off value of 2·7 per cent per min per m² has been used with hepatobiliary scintigraphy (HBS) for future remnant liver function (FRLF), patients with perihilar cholangiocarcinoma (PHC) potentially benefit from an additional cut‐off of 8·5 per cent/min (not corrected for body surface area). Since January 2016 a more liberal approach to PVE has been adopted, including this additional cut‐off for HBS of 8·5 per cent/min. The aim of this study was to assess the effect of this approach on liver failure and mortality.

Methods

This was a single‐centre retrospective study in which consecutive patients undergoing liver resection under suspicion of PHC in 2000–2015 were compared with patients treated in 2016–2019, after implementation of the more liberal approach. Primary outcomes were postoperative liver failure (International Study Group of Liver Surgery grade B/C) and 90‐day mortality.

Results

Some 191 patients with PHC underwent liver resection. PVE was performed in 6·4 per cent (9 of 141) of the patients treated in 2000–2015 and in 32 per cent (16 of 50) of those treated in 2016–2019. The 90‐day mortality rate decreased from 16·3 per cent (23 of 141) to 2 per cent (1 of 50) (P = 0·009), together with a decrease in the rate of liver failure from 19·9 per cent (28 of 141) to 4 per cent (2 of 50) (P = 0·008). In 2016–2019, 24 patients had a FRLF greater than 8·5 per cent/min and no liver failure or death occurred, suggesting that 8·5 per cent/min is a reliable cut‐off for patients with suspected PHC.

Conclusion

The major decrease in liver failure and mortality rates in recent years and the simultaneous increased use of PVE suggests an important role for PVE in reducing adverse outcomes after surgery for PHC.

Evaluation of segment 4 portal vein embolization added to right portal vein for right hepatic trisectionectomy: A retrospective propensity score-matched study

BACKGROUND

Adding segment 4 (S4) portal vein embolization (PVE) to right PVE before right hepatic trisectionectomy is controversial. We retrospectively examined the effect of S4 PVE on segments 2 and 3 (S2 + 3) hypertrophy.

METHODS

We reviewed patients with biliary carcinoma who underwent right PVE with (R3PVE) or without (R2PVE) S4 PVE using gelatin sponge particles and coils (2010-2019). Propensity score matching balanced the cohort for baseline characteristics, including total liver volume and S2 + 3 volume before PVE. We compared the groups regarding the S2 + 3 volume changes after PVE.

RESULTS

Of 178 enrolled patients, 38 underwent R3PVE for right hepatic trisectionectomy and 140 underwent R2PVE for right hepatectomy. Twenty-eight patients from each group were respectively matched. The median absolute volume increase in (146 cm³ vs 70 cm³ ), hypertrophy rate of (52.4% vs 32.3%), and kinetic growth rate of (3.1%/wk vs 2.0%/wk) S2 + 3 were significantly higher in the R3PVE group than in the R2PVE group. In the pre-matched cohort, the rate of posthepatectomy liver failure and postoperative hospital stay did not significantly differ between the patients who underwent right hepatic trisectionectomy and right hepatectomy.

CONCLUSION

R3PVE increased the S2 + 3 volume more effectively than R2PVE in patients with biliary carcinoma.

What are the most important predictive factors for clinically relevant posthepatectomy liver failure after right hepatectomy for hepatocellular carcinoma?

Purpose

The risk of posthepatectomy liver failure (PHLF) after right hepatectomy remains substantial. Additional parameters such as computed tomography volumetry, liver stiffness measurement by FibroScan, indocyanine green retention rate at 15 minutes, and platelet count used to properly assess future liver remnant volume quality and quantity are of the utmost importance. Thus, we compared the usefulness of these modalities for predicting PHLF among patients with hepatocellular carcinoma after right hepatectomy.

Methods

We retrospectively reviewed patients who underwent right hepatectomy for hepatocellular carcinoma between 2007 and 2013. PHLF was determined according to International Study Group of Liver Surgery consensus definition and severity grading. Grades B and C were defined as clinically relevant posthepatectomy liver failure (CRPHLF). The results were internally validated using a cohort of 97 patients.

Results

Among the 90 included patients, 15 (16.7%) had CRPHLF. Multivariate analysis confirmed that platelet count < 140 (10⁹/L) (hazard ratio [HR], 24.231; 95% confidence interval [CI], 3.623–161.693; P = 0.001) and remnant liver volume-to-body weight (RVL/BW) ratio < 0.55 (HR, 25.600; 95% CI, 4.185–156.590; P < 0.001) were independent predictors of CRPHLF. Among the 12 patients with a platelet count < 140 (10⁹/L) and RLV/BW ratio < 0.55, 9 (75%) had CRPHLF. Likewise, 5 of 38 (13.2%) with only one risk factor developed CRPHL versus 1 of 40 (2.5%) with no risk factors. These findings were confirmed by the validation cohort.

Conclusion

RLV/BW ratio and platelet count are more important than the conventional RLV/TFLV, indocyanine green retention rate at 15 minutes, and liver stiffness measurement in the preoperative risk assessment for CRPHLF.

Fifty-year history of biliary surgery

There has been enormous progress in the surgical treatment of biliary tract cancers in the past 50 years. In preoperative management, biliary drainage methods have changed from percutaneous transhepatic biliary drainage to endoscopic nasobiliary drainage, while the advent of multidetector-row computed tomography in imaging diagnostics now enables visualization of three-dimensional anatomy, extent of cancer progression, and hepatic segment volume. Portal vein embolization has also greatly improved the safety of extended hepatectomy, and indication of extended hepatectomy can now be objectively determined with a combination of the indocyanine green test and computed tomography volumetry. In terms of surgery, combined resection and reconstruction of the portal vein and/or hepatic artery can now be safely carried out at specialized centers. Further, long-term survival can be attained with combined vascular resection if R0 resection can be achieved, even in locally advanced cancer. Hepatopancreatoduodenectomy, combined major hepatectomy with pancreatoduodenectomy, should be aggressively carried out for laterally advanced cholangiocarcinoma, whereas its indication for advanced gallbladder cancer should be carefully evaluated. Japanese surgeons have made a significant contribution to the progression of extended surgeries such as combined vascular resection and hepatopancreatoduodenectomy for biliary tract cancer.

Survey of preoperative management protocol for perihilar cholangiocarcinoma at 10 Japanese high-volume centers with a combined experience of 2,778 cases

BACKGROUND

In Japan, strategies for preoperative management of perihilar cholangiocarcinoma (PHC) have evolved over the last decade; the operative mortality has significantly reduced to <5%.

METHODS

A questionnaire was sent to 10 institutions based on their case volume. Questionnaire was based on: (1) preoperative biliary drainage, (2) bile replacement, (3) role of synbiotics, (4) remnant liver volume enhancement, (5) predicted remnant liver function, (6) imaging, (7) nutrition, and (8) role of Inchinkoto.

RESULTS

The median case volume was 226 (range 105-889) cases, respectively. Eight institutions preferred endoscopic nasobiliary drainage and two preferred endoscopic biliary stenting for biliary drainage. Nine used bile replacement within 2-3 days of biliary drainage. Four used synbiotics preoperatively. The median cutoff value for future remnant liver volume and serum total bilirubin, at which portal vein embolization (PVE) is done, is <40% and <4 mg/dl. The median interval between PVE and surgery was 3-4 weeks. To predict remnant liver function, indocyanine green retention (n = 8) and clearance rate (n = 2) were mainly used. Five used Inchinkoto to improve liver function. Nine used multidetector computed tomography and direct cholangiography for surgical planning.

CONCLUSION

With appropriate preoperative management of PHC, surgical morbidity and mortality can be reduced. This survey can provide recommendations to improve PHC perioperative outcomes.

A comparison of treatment and outcomes of perihilar cholangiocarcinoma between Eastern and Western centers

BACKGROUND

Perihilar cholangiocarcinoma (PHC) often requires extensive surgery which is associated with substantial morbidity and mortality. This study aimed to compare an Eastern and Western PHC cohort in terms of patient characteristics, treatment strategies and outcomes including a propensity score matched analysis.

METHODS

All consecutive patients who underwent combined biliary and liver resection for PHC between 2005 and 2016 at two Western and one Eastern center were included. The overall perioperative and long-term outcomes of the cohorts were compared and a propensity score matched analysis was performed to compare perioperative outcomes.

RESULTS

A total of 210 Western patients were compared to 164 Eastern patients. Western patients had inferior survival compared to the East (hazard-ratio 1.72 (1-23-2.40) P < 0.001) corrected for age, ASA score, tumor stage and margin status. After propensity score matching, liver failure rate, morbidity, and mortality were similar. There was more biliary leakage (38% versus 13%, p = 0.015) in the West.

CONCLUSION

There were major differences in patient characteristics, treatment strategies, perioperative outcomes and survival between Eastern and Western PHC cohorts. Future studies should focus whether these findings are due to the differences in the treatment or the disease itself.

Predictors of post-hepatectomy liver failure in patients undergoing extensive liver resections for hepatocellular carcinoma

Backgrounds/Aims

To determine the prevalence of post-hepatectomy liver failure/insufficiency (PHLF/I) in patients undergoing extensive hepatic resections for hepatocellular carcinoma (HCC) and to assess the predictive value of preoperative factors for post-hepatectomy liver failure or insufficiency (PHLF/I).

Methods

A retrospective review of patients who underwent liver resections for HCC between 2001 and 2013 was conducted. Preoperative parameters were assessed and analyzed for their predictive value of PHLF/I. Definitions used included the 50–50, International Study Group of Liver Surgery (ISGLS) and Memorial Sloan Kettering Cancer Centre (MSKCC) criteria.

Results

Among the 848 patients who underwent liver resections for HCC between 2001 and 2013, 157 underwent right hepatectomy (RH) and extended right hepatectomy (ERH). The prevalence of PHLF/I was 7%, 41% and 28% based on the 50–50, ISGLS and MSKCC criteria, respectively. There were no significant differences in PHLF/I between RH and ERH. Model for End-Stage Liver Disease (MELD) score and bilirubin were the strongest independent predictors of PHLF/I based on the 50–50 and ISGLS/MSKCC criteria, respectively. Predictive models were developed for each of the criteria with multiple logistic regression.

Conclusions

MELD score, bilirubin, alpha-fetoprotein and platelet count showed significant predictive value for PHLF/I (all p<0.05). A composite score based on these factors serves as guideline for physicians to better select patients undergoing extensive resections to minimize PHLF.