ICG clearance in assessing cirrhotic patients with hepatocellular carcinoma for major hepatic resection

Prediction of Survival After Partial Hepatectomy Using a Physiologically Based Pharmacokinetic Model of Indocyanine Green Liver Function Tests

The evaluation of hepatic function and functional capacity of the liver are essential tasks in hepatology as well as in hepatobiliary surgery. Indocyanine green (ICG) is a widely applied test compound that is used in clinical routine to evaluate hepatic function. Important questions for the functional evaluation with ICG in the context of hepatectomy are how liver disease such as cirrhosis alters ICG elimination, and if postoperative survival can be predicted from preoperative ICG measurements. Within this work a physiologically based pharmacokinetic (PBPK) model of ICG was developed and applied to the prediction of the effects of a liver resection under various degrees of cirrhosis. For the parametrization of the computational model and validation of model predictions a database of ICG pharmacokinetic data was established. The model was applied (i) to study the effect of liver cirrhosis and liver resection on ICG pharmacokinetics; and (ii) to evaluate the model-based prediction of postoperative ICG-R15 (retention ratio 15 min after administration) as a measure for postoperative outcome. Key results are the accurate prediction of changes in ICG pharmacokinetics caused by liver cirrhosis and postoperative changes of ICG-elimination after liver resection, as validated with a wide range of data sets. Based on the PBPK model, individual survival after liver resection could be classified, demonstrating its potential value as a clinical tool.

Clinical factors predictive of insufficient liver enhancement on the hepatocyte-phase of Gd-EOB-DTPA-enhanced magnetic resonance imaging in patients with liver cirrhosis

BACKGROUND

Estimating liver parenchymal enhancement prior to gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance (MR) imaging is crucial to accurate detection and characterization of focal hepatic lesions. We aimed to clarify the factors predictive of liver enhancement in a relatively large sample of patients.

METHODS

Gd-EOB-DTPA-enhanced MR images of 328 patients with liver cirrhosis (Child-Pugh class A in 223 patients, class B in 71 patients, and class C in 34 patients) were analyzed retrospectively. The liver parenchymal signal intensity (SI) was measured in pre-contrast T1-weighted images and hepatocyte phase images. The relative enhancement (RE) was calculated: (hepatocyte phase SI-pre-contrast SI)/pre-contrast SI. We analyzed the correlation between hepatic function parameters and RE.

RESULTS

RE of patients with Child-Pugh A cirrhosis was significantly higher than that of patients with Child-Pugh B or C cirrhosis (both P < 0.001). Among various clinical factors, platelet count, prothrombin activity, albumin, sodium, total bilirubin, aspartate aminotransferase, Model for End-stage Liver Disease (MELD) score, MELD-Na score, Child-Pugh score, and the presence of ascites were significantly correlated with RE. A multiple stepwise regression analysis revealed that MELD-Na, albumin, and the presence of ascites were the only factors that predicted liver parenchymal enhancement on hepatocyte-phase images.

CONCLUSION

The degree of liver parenchymal enhancement after Gd-EOB-DTPA administration was correlated with liver function parameters. Gd-EOB-DTPA-enhanced MR images require careful interpretation, particularly in patients with cirrhosis and clinical factors such as high MELD-Na score, hypoalbuminemia, or ascites.

Essential parameters to consider for the characterization of optical imaging probes

The Molecular Imaging and Contrast Agents Database (MICAD) was launched in 2005 to promote the development and application of imaging and contrast agents (probes) to advance the field of molecular imaging. As of March 2012, there are approximately 1170 agents available in MICAD. Based on the modality used for imaging, the largest category of probes described in MICAD are those used for PET (41.6%), followed by agents used for single-photon emission computed tomography (30.3%), optical imaging (12.0%), MRI (9.3%), multimodality imaging (3.4%), ultrasound (2.4%) and x-ray/computed tomography (1.0%). This article is intended to be a guideline for new investigators and students who wish to characterize an optical imaging probe that will be used to perform in vivo molecular imaging studies. It is necessary, however, to ensure that these agents meet certain quality control parameters before they are used in various in vitro and in vivo applications.

Assessment of portal hypertension by transient elastography in patients with compensated cirrhosis and potentially resectable liver tumors

BACKGROUND & AIMS

Patients with cirrhosis and small hepatocellular carcinoma with normal bilirubin and hepatic venous pressure gradient (HVPG) <10 mm Hg have >70% 5-year survival after hepatic resection. On the contrary, patients with HVPG ≥10 mm Hg (clinically significant portal hypertension, CSPH) frequently develop decompensation following surgery, with around 50% 5-year survival. Liver stiffness (LS) evaluation by transient elastography might non-invasively identify CSPH. We investigated the usefulness of LS predicting CSPH in patients with compensated cirrhosis and potentially resectable liver tumors.

METHODS

Ninety-seven consecutive Child-Pugh A patients with potentially resectable liver tumors referred for HVPG measurement were prospectively evaluated. In fasting conditions LS was measured before the hemodynamic study.

RESULTS

HVPG could be measured in all patients, whereas LS could not be measured in 18 (18.5%) obese patients. In the 79 patients with valid LS, 32 (40.5%) had CSPH; mean HVPG was 8.8±4.7 mm Hg. Mean LS was 18.4±12.3 kPa. LS showed a moderate correlation with HVPG (r=0.552; p<0.001). LS<13.6 kPa had high sensitivity (91%) but low specificity (57%) excluding CSPH. Conversely, LS>21 kPa had low sensitivity (53%) and high specificity (91%) predicting CSPH. 35% of patients had LS between 13.6 and 21 kPa ("grey zone").

CONCLUSIONS

These data suggest that in real-life scenarios half of patients with potentially resectable liver nodules can be non-invasively classified as having or not CSPH by LS. However, in the remaining half, LS is either not applicable or inaccurate. In this last population HVPG is still a non replaceable method to detect CSPH.

Noninvasive evaluation of liver disease severity

In assessing the severity of chronic liver disease, one measures either the fibrotic structure of the liver or liver function. This article reviews the methods for evaluating the severity of liver disease noninvasively by estimating function or structure.

In-contiguity and non-anatomical extension of right hepatic trisectionectomy for liver metastases

Background

In some patients undergoing right hepatic trisectionectomy for metastases, extension of the resection beyond the falciform ligament is necessary to achieve tumour clearance. The aim of the present study was to assess the early and long-term outcomes and hepatic function in patients who underwent extensive liver resection beyond right trisectionectomy.

Methods

Thirty-eight patients who had extension of a right trisectionectomy, either in contiguity (IC) or in a non-anatomical (NA) fashion, for liver metastases were included in the study. In-hospital mortality, hepatic function and other morbidity were recorded. Survival outcomes were analysed for the subgroup of patients with colorectal liver metastases. The clinical risk score described by the Memorial Sloan–Kettering Cancer Center was applied to all patients with colorectal liver metastases.

Results

Sixteen patients had IC resection, 15 NA resection, and seven had both IC and NA procedures. There was one in-hospital death. Hepatic dysfunction was seen in 25 patients and two developed liver failure. Disease-free actuarial 3-year survival was 42 per cent for patients with colorectal liver metastases. Survival was significantly better in patients with a clinical risk score of 3 or less.

Conclusion

Extension of right trisectionectomy for liver metastases was associated with a low risk of death and hepatic failure.

Quantitative liver-spleen scan using single photon emission computerized tomography (SPECT) for assessment of hepatic function in cirrhotic patients

BACKGROUND/AIMS

Accurate quantitative determination of liver function is critical in cirrhotic patients in order to predict outcome, particularly in patients who undergo hepatic resection or non-hepatic surgery. As colloid uptake by perfused Kupffer cells is proportional to perfused hepatocyte mass, quantitative liver spleen scan may be used as an index of perfused hepatocyte mass. Thus, this study was conducted to evaluate quantitative single photon emission computerized tomography (SPECT) of Tc-99mm-phytate colloid uptake by the liver as a test for hepatic function in cirrhotic patients.

METHODS

Quantitative SPECT was used to measure liver volume, quantitative colloid uptake by the liver and percentage of injected dose/ml of liver tissue in cirrhotic patients (n=75), non-cirrhotic patients with chronic liver disease (n=52) and patients without liver disease (n=36).

RESULTS

Although liver volume was similar among the three groups, the cirrhotic patients had significantly lower total quantitative uptake and quantitative uptake/ml compared to groups 2 and 3 (P<0.001). Quantitative liver uptake in the cirrhotic patients was highly correlated with Child-Pugh score (r=-0.64, P<0.0001) and with indocyanine green retention at 15 min (r=-0.84, P<0.0001).

CONCLUSIONS

Quantitative SPECT of the liver may be an additional, useful, non-invasive quantitative test for assessment of hepatic function and severity of liver disease in cirrhotic patients.

Preoperative galactose elimination capacity predicts complications and survival after hepatic resection

OBJECTIVE

To analyze a single center's 6-year experience with 258 consecutive patients undergoing major hepatic resection for primary or secondary malignancy of the liver, and to examine the predictive value of preoperative liver function assessment.

SUMMARY BACKGROUND DATA

Despite the substantial improvements in diagnostic and surgical techniques that have made liver surgery a safer procedure, careful patient selection remains mandatory to achieve good results in patients with hepatic tumors.

METHODS

In this prospective study, 258 patients undergoing hepatic resection were enrolled: 111 for metastases, 78 for hepatocellular carcinoma (HCC), 21 for cholangiocellular carcinoma, and 48 for other primary hepatic tumors. One hundred fifty-eight patients underwent segment-oriented liver resection, including hemihepatectomies, and 100 had subsegmental resections. Thirty-two clinical and biochemical parameters were analyzed, including liver function assessment by the galactose elimination capacity (GEC) test, a measure of hepatic functional reserve, to predict postoperative (60-day) rates of death and complications and long-term survival. All variables were determined within 5 days before surgery. Data were subjected to univariate and multivariate analysis for two patient subgroups (HCC and non-HCC). The cutoffs for GEC in both groups were predefined. Long-term survival (>60 days) was subjected to Kaplan-Meier analysis and the Cox proportional hazard model.

RESULTS

In the entire group of 258 patients, a GEC less than 6 mg/min/kg was the only preoperative biochemical parameter that predicted postoperative complications and death by univariate and stepwise regression analysis. A GEC of more than 6 mg/min/kg was also significantly associated with longer survival. This predictive value could also be shown in the subgroup of 180 patients with tumors other than HCC. In the subgroup of 78 patients with HCC, a GEC less than 4 mg/min/kg predicted postoperative complications and death by univariate and stepwise regression analysis. Further, a GEC of more than 4 mg/min/kg was also associated with longer survival.

CONCLUSIONS

This prospective study establishes the preoperative determination of the hepatic reserve by GEC as a strong independent and valuable predictor for short- and long-term outcome in patients with primary and secondary hepatic tumors undergoing resection.

The clinical importance of the trimethadione tolerance test as a method for quantitative assessment of hepatic functional reserve in patients with biliary atresia

BACKGROUND

The trimethadione (TMO) tolerance test was performed to evaluate its usefulness in the assessment of hepatic functional reserve in patients with biliary atresia.

METHOD

Nineteen patients with biliary atresia after hepatic portoenterostomy (age range: 2 months to 25 years; sex: 6 males and 13 females) were studied. The study was performed in the morning after a 12-h fast. TMO was given orally, at a dose of 4 mg/kg, with 5 mL of 5% glucose 2 h before breakfast. Blood samples (0.5 mL) were collected to determine serum TMO and dimethadione (DMO), a metabolite of TMO, levels 4 h after the administration of TMO. TMO and DMO were measured by a gas-liquid chromatographic method.

RESULTS

A higher total bilirubin level (over 1 mg/dL) in patients with jaundice was reflected in the smaller serum DMO/TMO ratio 4 h after the oral administration of TMO. In addition, these patients with total bilirubin levels of 1 mg/dL or less had a significantly lower DMO/TMO ratio than the control group (healthy subjects). The serum DMO/TMO ratio showed a close correlation with the Child-Pugh score, which is used for overall evaluation of severity of cirrhosis and Mayo risk scores for primary biliary cirrhosis in adults (0.856, P < 0.01 and 0.788, P < 0.01, respectively). The TMO tolerance test shows the benefit of performing a relatively early test of dynamic liver function to evaluate hepatic functional reserve in pre- and post-operative biliary atresia patients.