Liver function declines with increased age.

INTRODUCTION: Age itself is not considered a contraindication for high impact surgery. However, the aging process of the liver remains largely unknown. This study evaluates age-dependent changes in liver function using a quantitative liver function test. METHODS: Between January 2005 and December 2014, 508 patients underwent (99m)Tc-mebrofenin hepatobiliary scintigraphy (HBS) for the assessment of liver function. These included 203 patients with healthy livers (group A) and 57 patients with HCC and Child-Pugh A (group B). (99m)Tc-mebrofenin-uptake-rate of the whole liver corrected for body surface area (cMUR) was calculated for all patients. Linear regression analysis was performed to assess the relationship between age and cMUR. RESULTS: The mean cMUR was 8.50 ± 2.05%/min/m(2) and 6.94 ± 2.03%/min/m(2) in group A and B, respectively. A negative linear correlation was found between patient's age and cMUR in group A, r = 0.244, p = 0.000. In group B, there was no correlation between age and cMUR, however, a trend in decline of liver function with age was noted. CONCLUSION: This study shows that liver function deteriorates with age. Since the regenerative capacity of the liver correlates with liver function, this finding should be taken into account when assessing surgical risk in patients considered for major liver resection.

Measurement of liver function using hepatobiliary scintigraphy improves risk assessment in patients undergoing major liver resection.

BACKGROUND: (99m)Tc-mebrofenin-hepatobiliary-scintigraphy (HBS) enables measurement of future remnant liver (FRL)-function and was implemented in our preoperative routine after calculation of the cut-off value for prediction of postoperative liver failure (LF). This study evaluates our results since the implementation of HBS. Additionally, CT-volumetric methods of FRL-assessment, standardized liver volumetry and FRL/body-weight ratio (FRL-BWR), were evaluated. METHODS: 163 patients who underwent major liver resection were included. Insufficient FRL-volume and/or FRL-function <2.7%/min/m(2) were indications for portal vein embolization (PVE). Non-PVE patients were compared with a historical cohort (n = 55). Primary endpoints were postoperative LF and LF related mortality. Secondary endpoint was preoperative identification of patients at risk for LF using the CT-volumetric methods. RESULTS: 29/163 patients underwent PVE; 8/29 patients because of insufficient FRL-function despite sufficient FRL-volume. According to FRL-BWR and standardized liver volumetry, 16/29 and 11/29 patients, respectively, would not have undergone PVE. LF and LF related mortality were significantly reduced compared to the historical cohort. HBS appeared superior in the identification of patients with increased surgical risk compared to the CT-volumetric methods. DISCUSSION: Implementation of HBS in the preoperative work-up led to a function oriented use of PVE and was associated with a significant decrease in postoperative LF and LF related mortality.

Comparison of techniques for volumetric analysis of the future liver remnant: implications for major hepatic resections.

OBJECTIVE: The purpose of this work was to compare measured and estimated volumetry prior to liver resection. METHODS: Data for consecutive patients submitted to major liver resection for colorectal liver metastases at two centres during 2004-2012 were reviewed. All patients underwent volumetric analysis to define the measured total liver volume (mTLV) and measured future liver remnant ratio (mR(FLR)). The estimated total liver volume (eTLV) standardized to body surface area and estimated future liver remnant ratio (eR(FLR)) were calculated. Descriptive statistics were generated and compared. A difference between mR(FLR) and eR(FLR) of ±5% was considered clinically relevant. RESULTS: Data for a total of 116 patients were included. All patients underwent major resection and 51% underwent portal vein embolization. The mean difference between mTLV and eTLV was 157 ml (P < 0.0001), whereas the mean difference between mR(FLR) and eR(FLR) was -1.7% (P = 0.013). By linear regression, eTLV was only moderately predictive of mTLV (R(2) = 0.35). The distribution of differences between mR(FLR) and eR(FLR) demonstrated that the formula over- or underestimated mR(FLR) by ≥5% in 31.9% of patients. CONCLUSIONS: Measured and estimated volumetry yielded differences in the FLR of ≥5% in almost one-third of patients, potentially affecting clinical decision making. Estimated volumetry should be used cautiously and cannot be recommended for general use.

The role of routine preoperative EUS when performed after contrast enhanced CT in the diagnostic work-up in patients suspected of pancreatic or periampullary cancer.

BACKGROUND: In patients suspected of pancreatic or periampullary cancer, abdominal contrast-enhanced computed tomography (CT) is the standard diagnostic modality. A supplementary endoscopic ultrasonography (EUS) is often performed, although there is only limited evidence of its additional diagnostic value. The aim of the study is to evaluate the additional diagnostic value of EUS over CT in deciding on exploratory laparotomy in patients suspected of pancreatic or periampullary cancer. METHODS: We retrospectively analyzed 86 consecutive patients who routinely underwent CT and EUS before exploratory laparotomy with or without pancreatoduodenectomy for suspected pancreatic or periampullary carcinoma between 2007 and 2010. Primary outcomes were visibility of a mass, resectability on CT/EUS and resection with curative intent. RESULTS: A mass was visible on CT in 72/86 (84%) patients. In these 72 patients, EUS demonstrated a mass in 64/72 (89%) patients. Resectability was accurately predicted by CT in 65/72 (90%) and by EUS in 58/72 (81%) patients. In 14/86 (16%) patients no mass was seen on CT. EUS showed a mass in 12/14 (86%) of these patients. A malignant lesion was histological proven in 11/12 (92%) of these patients. Overall, resectability was accurately predicted by CT and EUS in 90% (77/86) and 84% (72/86), respectively. CONCLUSIONS: In patients with a visible mass on CT, suspected for pancreatic or periampullary cancer, EUS has no additional diagnostic value, does not influence the decision to perform laparotomy and should therefore not be performed routinely. In patients without a visible mass on CT, EUS is useful to confirm the presence of a tumor.

New perspectives in the assessment of future remnant liver.

In order to achieve microscopic radical resection margins and thus better survival, surgical treatment of hepatic tumors has become more aggressive in the last decades, resulting in an increased rate of complex and extended liver resections. Postoperative outcomes mainly depend on the size and quality of the future remnant liver (FRL). Liver resection, when performed in the absence of sufficient FRL, inevitably leads to postresection liver failure. The current gold standard in the preoperative assessment of the FRL is computed tomography volumetry. In addition to the volume of the liver remnant after resection, postoperative function of the liver remnant is directly related to the quality of liver parenchyma. The latter is mainly influenced by underlying diseases such as cirrhosis and steatosis, which are often inaccurately defined until microscopic examination after the resection. Postresection liver failure remains a point of major concern that calls for accurate methods of preoperative FRL assessment. A wide spectrum of tests has become available in the past years, attesting to the fact that the ideal methodology has yet to be defined. The aim of this review is to discuss the current modalities available and new perspectives in the assessment of FRL in patients scheduled for major liver resection.

The utility of 99mTc-mebrofenin hepatobiliary scintigraphy with SPECT/CT for selective internal radiation therapy in hepatocellular carcinoma.

BACKGROUND: Studies assessing the impact of selective internal radiation therapy (SIRT) on the regional liver function in patients with hepatocellular carcinoma (HCC) are sparse. This study assessed the changes in total and regional liver function using hepatobiliary scintigraphy (HBS) and investigated the utility of HBS to predict post-SIRT liver dysfunction. METHODS: Patients treated with SIRT for HCC between 2011 and 2019, underwent Tc-mebrofenin HBS with single-photon emission computed tomography/computed tomography (SPECT/CT) before and 6 weeks after SIRT. The corrected mebrofenin uptake rate (cMUR) and corresponding volume was measured in the total liver, and in treated and nontreated liver regions. Patients with and without post-SIRT liver dysfunction were compared. RESULTS: A total of 29 patients, all Child-Pugh-A and mostly intermediate (72%) stage HCC were included in this study. Due to SIRT, the cMURtotal declined from 5.8 to 4.5%/min/m (P < 0.001). Twenty-two patients underwent a lobar SIRT, which induced a decline in cMUR (2.9-1.7%/min/m, P < 0.001) and volume (1228-1101, P = 0.002) of the treated liver region, without a change in cMUR (2.4-2.0%/min/m, P = 0.808) or volume (632-644 mL, P = 0.661) of the contralateral nontreated lobe. There were no significant pre-SIRT differences in total or regional cMUR or volume between patients with and without post-SIRT liver dysfunction. CONCLUSION: In patients treated with SIRT for HCC, HBS accurately identified changes in total and regional liver function and may have a complementary role to personalize lobar or selective SIRT. In this pilot study, there were no pre-SIRT differences in cMUR or volume to aid in predicting post-SIRT liver dysfunction.

Stress test of liver function using technetium-99m-mebrofenin hepatobiliary scintigraphy.

Technetium-99m (Tc) mebrofenin hepatobiliary scintigraphy (HBS) enables a quantitative assessment of liver function. This is normally performed in a fasting state and might therefore reflect the resting liver function. We evaluated the change in liver function using HBS after stimulation with an oral metabolic challenge. Healthy volunteers aged 50-60 (n=12) or older than or equal to 75 (n=12) years underwent two sequential HBS. The first scan was performed after an overnight fast and the second scan was performed after the administration of chocolate milk. Hepatic Tc-mebrofenin uptake rate (cMUR) was calculated and the difference was expressed as percentage. cMUR after fasting was 10.9±2.5%/min/m (mean±SD) and increased by 20% to 13.0±3.1%/min/m after stimulation with chocolate milk (P<0.001). cMUR increased markedly after the administration of an oral metabolic challenge in comparison with fasting. This may be a consequence of hepatocyte stimulation, reflecting the hepatic functional reserve capacity.

A pharmacokinetic model including arrival time for two inputs and compensating for varying applied flip-angle in dynamic gadoxetic acid-enhanced MR imaging.

PURPOSE: Pharmacokinetic models facilitate assessment of properties of the micro-vascularization based on DCE-MRI data. However, accurate pharmacokinetic modeling in the liver is challenging since it has two vascular inputs and it is subject to large deformation and displacement due to respiration. METHODS: We propose an improved pharmacokinetic model for the liver that (1) analytically models the arrival-time of the contrast agent for both inputs separately; (2) implicitly compensates for signal fluctuations that can be modeled by varying applied flip-angle e.g. due to B1-inhomogeneity. Orton's AIF model is used to analytically represent the vascular input functions. The inputs are independently embedded into the Sourbron model. B1-inhomogeneity-driven variations of flip-angles are accounted for to justify the voxel's displacement with respect to a pre-contrast image. RESULTS: The new model was shown to yield lower root mean square error (RMSE) after fitting the model to all but a minority of voxels compared to Sourbron's approach. Furthermore, it outperformed this existing model in the majority of voxels according to three model-selection criteria. CONCLUSION: Our work primarily targeted to improve pharmacokinetic modeling for DCE-MRI of the liver. However, other types of pharmacokinetic models may also benefit from our approaches, since the techniques are generally applicable.

Liver related complications in unresectable disease after portal vein embolization.

BACKGROUND: Portal vein embolization (PVE) is used preoperatively in patients to increase future remnant liver volume (FRLV). Unfortunately, some patients are found to be unresectable at exploration due to tumor progression or new lesions. The aim of this study is to evaluate the long-term effects of PVE in the embolized liver lobe when left unresected. METHODS: Of 85 patients who underwent right PVE, 16 (19%) were unresectable (PVE-group). These patients were compared with 48 randomly matched patients from a pool of 75 unresectable patients who had not undergone PVE. Primary outcome parameter was occurrence of infectious complications (liver abscesses) on follow-up imaging of the liver. The long-term volumetric changes of the hypertrophy/atrophy complex were assessed as secondary outcome parameter. RESULTS: Five of 16 (31%) patients in PVE-group developed an abscess vs. 4 (8%) patients in non-PVE group (P=0.022). The volume distribution of left and right liver lobes (hypertrophy-atrophy rate) increased from 26%:74% before embolization to 36%:64% three weeks after PVE and to 51%:49% six months after PVE. CONCLUSIONS: Persistence of embolized liver lobe in unresectable patients after PVE resulted in abscesses in 31%. This observation calls for developing reversible embolization techniques using absorbable materials in patients with uncertain resectability.

Correction: Worldwide trends in volume and quality of published protocols of randomized controlled trials.

[This corrects the article DOI: 10.1371/journal.pone.0173042.].

Future remnant liver function as predictive factor for the hypertrophy response after portal vein embolization.

BACKGROUND: Preoperative portal vein embolization is widely used to increase the future remnant liver. Identification of nonresponders to portal vein embolization is essential because these patients may benefit from associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), which induces a more powerful hypertrophy response. 99mTc-mebrofenin hepatobiliary scintigraphy is a quantitative method for assessment of future remnant liver function with a calculated cutoff value for the prediction of postoperative liver failure. The aim of this study was to analyze future remnant liver function before portal vein embolization to predict sufficient functional hypertrophy response after portal vein embolization. METHODS: Sixty-three patients who underwent preoperative portal vein embolization and computed tomography imaging were included. Hepatobiliary scintigraphy was performed to determine pre-portal vein embolization and post-portal vein embolization future remnant liver function. Receiver operator characteristic analysis of pre-portal vein embolization future remnant liver function was performed to identify patients who would meet the post-portal vein embolization cutoff value for sufficient function (ie, 2.7%/min/m2). RESULTS: Mean pre-portal vein embolization future remnant liver function was 1.80% ± 0.45%/min/m2 and increased to 2.89% ± 0.97%/min/m2 post-portal vein embolization. Receiver operator characteristic analysis in 33 patients who did not receive chemotherapy revealed that a pre-portal vein embolization future remnant liver function of ≥1.72%/min/m2 was able to identify patients who would meet the safe future remnant liver function cutoff value 3 weeks after portal vein embolization (area under the curve = 0.820). The predictive value was less pronounced in 30 patients treated with neoadjuvant chemotherapy (area under the curve = 0.618). A total of 45 of 63 patients underwent liver resection, of whom 5 of 45 developed postoperative liver failure; 4 of 5 patients had a post-portal vein embolization future remnant liver function below the cutoff value for safe resection. CONCLUSION: When selecting patients for portal vein embolization, future remnant liver function assessed with hepatobiliary scintigraphy can be used as a predictor of insufficient functional hypertrophy after portal vein embolization, especially in nonchemotherapy patients. These patients are potential candidates for ALPPS.

Worldwide trends in volume and quality of published protocols of randomized controlled trials.

INTRODUCTION: Publishing protocols of randomized controlled trials (RCT) facilitates a more detailed description of study rational, design, and related ethical and safety issues, which should promote transparency. Little is known about how the practice of publishing protocols developed over time. Therefore, this study describes the worldwide trends in volume and methodological quality of published RCT protocols. METHODS: A systematic search was performed in PubMed and EMBASE, identifying RCT protocols published over a decade from 1 September 2001. Data were extracted on quality characteristics of RCT protocols. The primary outcome, methodological quality, was assessed by individual methodological characteristics (adequate generation of allocation, concealment of allocation and intention-to-treat analysis). A comparison was made by publication period (First, September 2001- December 2004; Second, January 2005-May 2008; Third, June 2008-September 2011), geographical region and medical specialty. RESULTS: The number of published RCT protocols increased from 69 in the first, to 390 in the third period (p<0.0001). Internal medicine and paediatrics were the most common specialty topics. Whereas most published RCT protocols in the first period originated from North America (n = 30, 44%), in the second and third period this was Europe (respectively, n = 65, 47% and n = 190, 48%, p = 0.02). Quality of RCT protocols was higher in Europe and Australasia, compared to North America (OR = 0.63, CI = 0.40-0.99, p = 0.04). Adequate generation of allocation improved with time (44%, 58%, 67%, p = 0.001), as did concealment of allocation (38%, 53%, 55%, p = 0.03). Surgical protocols had the highest quality among the three specialty topics used in this study (OR = 1.94, CI = 1.09-3.45, p = 0.02). CONCLUSION: Publishing RCT protocols has become popular, with a five-fold increase in the past decade. The quality of published RCT protocols also improved, although variation between geographical regions and across medical specialties was seen. This emphasizes the importance of international standards of comprehensive training in RCT methodology.

Postoperative Mortality after Liver Resection for Perihilar Cholangiocarcinoma: Development of a Risk Score and Importance of Biliary Drainage of the Future Liver Remnant.

BACKGROUND: Liver surgery for perihilar cholangiocarcinoma (PHC) is associated with postoperative mortality ranging from 5% to 18%. The aim of this study was to develop a preoperative risk score for postoperative mortality after liver resection for PHC, and to assess the effect of biliary drainage of the future liver remnant (FLR). STUDY DESIGN: A consecutive series of 287 patients submitted to major liver resection for presumed PHC between 1997 and 2014 at 2 Western centers was analyzed; 228 patients (79%) underwent preoperative drainage for jaundice. Future liver remnant volumes were calculated with CT volumetry and completeness of FLR drainage was assessed on imaging. Logistic regression was used to develop a mortality risk score. RESULTS: Postoperative mortality at 90 days was 14% and was independently predicted by age (odds ratio [OR] per 10 years = 2.1), preoperative cholangitis (OR = 4.1), FLR volume <30% (OR = 2.9), portal vein reconstruction (OR = 2.3), and incomplete FLR drainage in patients with FLR volume <50% (OR = 2.8). The risk score showed good discrimination (area under the curve = 0.75 after bootstrap validation) and ranking patients in tertiles identified 3 (ie low, intermediate, and high) risk subgroups with predicted mortalities of 2%, 11%, and 37%. No postoperative mortality was observed in 33 undrained patients with FLR volumes >50%, including 10 jaundiced patients (median bilirubin level 11 mg/dL). CONCLUSIONS: The mortality risk score for patients with resectable PHC can be used for patient counseling and identification of modifiable risk factors, which include FLR volume, FLR drainage status, and preoperative cholangitis. We found no evidence to support preoperative biliary drainage in patients with an FLR volume >50%.

Assessment of Liver Function Using (99m)Tc-Mebrofenin Hepatobiliary Scintigraphy in ALPPS (Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy).

ALPPS (associating liver partition and portal vein ligation for staged hepatectomy) is a new surgical technique for patients in whom conventional treatment is not feasible due to insufficient future remnant liver (FRL). During the first stage of ALPPS, accelerated hypertrophy of the FRL is induced by ligation of the portal vein and in situ split of the liver. In the second stage, the deportalized liver is removed when the FRL volume has reached ≥25% of total liver volume. However, FRL volume does not necessarily reflect FRL function. (99m)Tc-mebrofenin hepatobiliary scintigraphy (HBS) with SPECT-CT is a quantitative test enabling regional assessment of parenchymal uptake function using a validated cut-off value for the prediction of postoperative liver failure (2.7%/min/m(2)). This paper describes the changes in FRL function and FRL volume in a 79-year-old patient diagnosed with metachronous colonic liver metastases who underwent ALPPS. We have observed a substantial difference between the increase in FRL volume and FRL function suggesting that HBS with SPECT-CT enables monitoring of the FRL function and could be a useful tool in the timing of resection in the second stage of the ALPPS procedure.

Monitoring of Total and Regional Liver Function after SIRT.

Selective internal radiation therapy (SIRT) is a promising treatment modality for advanced hepatocellular carcinoma or metastatic liver cancer. SIRT is usually well tolerated. However, in most patients, SIRT will result in a (temporary) decreased liver function. Occasionally patients develop radioembolization-induced liver disease (REILD). In case of a high tumor burden of the liver, it could be beneficial to perform SIRT in two sessions enabling the primary untreated liver segments to guarantee liver function until function in the treated segments has recovered or functional hypertrophy has occurred. Clinically used liver function tests provide evidence of only one of the many liver functions, though all of them lack the possibility of assessment of segmental (regional) liver function. Hepatobiliary scintigraphy (HBS) has been validated as a tool to assess total and regional liver function in liver surgery. It is also used to assess segmental liver function before and after portal vein embolization. HBS is considered as a valuable quantitative liver function test enabling assessment of segmental liver function recovery after regional intervention and determination of future remnant liver function. We present two cases in which HBS was used to monitor total and regional liver function in a patient after repeated whole liver SIRT complicated with REILD and a patient treated unilaterally without complications.

Efficacy and complications of nasojejunal, jejunostomy and parenteral feeding after pancreaticoduodenectomy.

BACKGROUND: European nutritional guidelines recommend routine use of enteral feeding after pancreaticoduodenectomy (PD) whereas American guidelines do not. Data on the efficacy and, especially, complications of the various feeding strategies after PD are scarce. METHODS: Retrospective monocenter cohort study in 144 consecutive patients who underwent PD during a period wherein the routine post-PD feeding strategy changed twice. Patients not receiving nutritional support (n=15) were excluded. Complications were graded according to the Clavien-Dindo classification and the International Study Group of Pancreatic Surgery (ISGPS) definitions. Analysis was by intention-to-treat. Primary endpoint was the time to resumption of normal oral intake. RESULTS: 129 patients undergoing PD (111 pylorus preserving) were included. 44 patients (34%) received enteral nutrition via nasojejunal tube (NJT), 48 patients (37%) via jejunostomy tube (JT) and 37 patients (29%) received total parenteral nutrition (TPN). Groups were comparable with respect to baseline characteristics, Clavien ≥II complications (P=0.99), in-hospital stay (P=0.83) and mortality (P=0.21). There were no differences in time to resumption of normal oral intake (primary endpoint; NJT/JT/TPN: median 13, 16 and 14 days, P=0.15) and incidence of delayed gastric emptying (P=0.30). Duration of enteral nutrition was shorter in the NJT- compared to the JT- group (median 8 vs. 12 days, P=0.02). Tube related complications occurred mainly in the NJT-group (34% dislodgement). In the JT-group, relaparotomy was performed in three patients (6%) because of JT-leakage or strangulation leading to death in one patient (2%). Wound infections were most common in the TPN group (NJT/JT/TPN: 16%, 6% and 30%, P=0.02). CONCLUSION: None of the analysed feeding strategies was found superior with respect to time to resumption of normal oral intake, morbidity and mortality. Each strategy was associated with specific complications. Nasojejunal tubes dislodged in a third of patients, jejunostomy tubes caused few but potentially life-threatening bowel strangulation and TPN doubled the risk of infections.

[Pancreatoduodenectomy for suspected malignancy: indications, complications and survival]. / Pancreatoduodenectomie bij verdenking op maligniteit: indicaties, complicaties en overleving.

OBJECTIVE: To evaluate the indications, complications and survival after pancreatoduodenectomy, with special attention for the outcome after extended resection due to tumour extension and in elderly patients. DESIGN: Retrospective, partly cross-sectional study. METHOD: All 275 consecutive adult patients who underwent explorative laparotomy for a suspected resectable pancreatic head tumour or periampulary tumour in two Dutch tertiary centres between 2007 and 2010 were included. We graded the postoperative complications according to international classifications and collected data on survival. RESULTS: In 218/275 patients (79%) the tumour could be resected by pancreatoduodenectomy with or without an extended resection. Malignancy was confirmed in 190/218 patients (87%); in 153/190 patients (81%) a microscopically radical (R0) resection was achieved. Fifteen percent of the patients required a re-intervention (radiological, endoscopic or surgical) because of an intra-abdominal complication. The post-operative 30-day mortality was 4.1%. Eighty-six patients (39%) were ultimately diagnosed with 'pancreatic adenocarcinoma'; they had a 1- and 2-year survival rate of 63% and 34%, respectively. In 27 patients (12%) who underwent an extended resection for oncological reasons, such as partial hepatic portal vein resection, the 30-day mortality was 0% and the survival rates were comparable to patients with a standard resection. The 81 patients (37%) aged 70 or older had a 30-day mortality and survival similar to younger patients. CONCLUSION: More than 75% of potentially resectable tumours were resected by a pancreatoduodenectomy with or without an extended resection, with a relatively low postoperative mortality and an adequate survival benefit. After multidisciplinary assessment, both limited tumour extension and a higher age are not necessarily contraindications for a resection, as a comparable survival benefit can be obtained for these groups of patients as for other groups.