Dose adaptation of antineoplastic drugs in patients with liver disease

Treatment of obstructive jaundice induced by non-hodgkin lymphoma with EUS-guided transgastric anterograde common bile duct stenting: Technical case report and literature review

Background

Non-Hodgkin lymphoma (NHL) is a rare cause of biliary obstruction. The optimum treatment for these patients is unclear. Lymphoma-associated obstructive jaundice is generally managed with open surgery, Endoscopic retrograde cholangiopancreatography (ERCP), or Percutaneous transhepatic biliary drainage. Here, we present the first description of EUS-guided anterograde common bile duct stenting via the stomach for obstructive jaundice associated with NHL.

Patient and methods

A 58-year-old male patient who had been undergoing chemotherapy for NHL was admitted to our institution for severe obstructive jaundice. The patient's hepatic function indicators were: alanine aminotransferase 211 U/L, aspartate aminotransferase 301 U/L, total bilirubin 485.6 μmol/L, and direct bilirubin 340.2 μmol/L. Abdominal magnetic resonance imaging showed massive lymphomatous lesions filling the peritoneal cavity. Magnetic resonance cholangiopancreatography revealed an external compressive stricture in the superior middle common bile duct and dilation of the intrahepatic and extrahepatic ducts. ERCP was performed unsuccessfully, due to the stricture at the descending junction of the duodenal bulb caused by lymphoma infiltration. So, EUS-guided anterograde common bile duct stenting via the stomach was performed.

Results

The patient's bilirubin level decreased significantly in the postoperative period, and no adverse reaction was observed. Computed tomography showed marked shrinking of the abdominal mass after targeted therapy.

Conclusions

Our report suggests that early relief of biliary obstruction may be more beneficial to subsequent chemotherapy when symptoms of lymphoma-associated jaundice are persistently aggravating. Endoscopic ultrasound-guided biliary drainage is a safe, effective and timely alternative approach to treat biliary obstruction when ERCP fails, especially in cases of malignancy caused by extrahepatic bile duct space-occupying lesions.

Bile Acid Dysregulation Is Intrinsically Related to Cachexia in Tumor-Bearing Mice

Simple Summary

Cancer cachexia is considered a multi-organ syndrome. An improved understanding of how circulating molecules can affect tissues and mediate their crosstalk in the pathogenesis of cancer cachexia is emerging. Considering the various actions of bile acids on host metabolism and immunity, they could represent innovative targets in cancer cachexia. In this study, we investigated how bile acids could contribute to this syndrome by assessing the bile flow, by comparing the impact on bile acid pathways of cachexia-inducing and non-cachexia-inducing cell sublines, and by investigating the effects of ursodeoxycholic acid, a choleretic compound, in cachectic mice. Altogether, our analyses strengthen the importance of bile acids and their receptors as key players in the metabolic disorders associated with cancer, thereby laying the foundation for new therapeutic opportunities.

Abstract

Bile acids exert diverse actions on host metabolism and immunity through bile acid-activated receptors, including Takeda G protein-coupled receptor 5 (TGR5). We have recently evidenced an alteration in bile acids in cancer cachexia, an inflammatory and metabolic syndrome contributing to cancer death. This current study aims to further explore the links emerging between bile acids and cancer cachexia. First, we showed that bile flow is reduced in cachectic mice. Next, comparing mice inoculated with cachexia-inducing and with non-cachexia-inducing C26 colon carcinoma cells, we demonstrated that alterations in the bile acid pathways and profile are directly associated with cachexia. Finally, we performed an interventional study using ursodeoxycholic acid (UDCA), a compound commonly used in hepatobiliary disorders, to induce bile acid secretion and decrease inflammation. We found that UDCA does not improve hepatic inflammation and worsens muscle atrophy in cachectic mice. This exacerbation of the cachectic phenotype upon UDCA was accompanied by a decreased TGR5 activity, suggesting that TGR5 agonists, known to reduce inflammation in several pathological conditions, could potentially counteract cachectic features. This work brings to light major evidence sustaining the emerging links between bile acids and cancer cachexia and reinforces the interest in studying bile acid-activated receptors in this context.

Rethinking toxicity testing: Influence of aging on the outcome of long-term toxicity testing and possible remediation

Traditionally, toxicity testing is conducted at fixed dose rates (i.e., mg/kg/day) without considering life-changing events, e.g., stress, sickness, aging- and/or pregnancy-related changes in physical, physiological and biochemical parameters. In humans, life-changing events may cause systemic dose non-proportionality requiring modulation of drug dosage; similar changes occur in animals altering systemic dose during chronic/carcinogenic testing leading to "late-occurring" effects in some studies. For example, propylene monomethyl ether, an industrial chemical, initially induced sedation in rats and mice with recovery upon induction of hepatic CYPs after ~1 week. Sedation reappeared in rats but not in mice after ~12 months of exposure due to decreased CYP activity in rats, elderly mice were able to maintain slightly higher CYP activity avoiding recurrence of sedation. The systemic dose of two pharmaceuticals (doxazosin and brimonidine tartrate) increased up to 6-fold in ≥12-month old rats with no toxicity. In a rat reproductive toxicity study, systemic dose of 2,4-D, an herbicide, rapidly increased due to increased consumption of 2,4-D-fortified diet during pregnancy, lactation and neonatal growth, requiring adjustment to maintain the targeted systemic dose. Ideally, toxicological studies should be based on systemic dose with the option of modulating external dose rates to maintain the targeted systemic dose. Systemic dose can easily be monitored in selected core study animals at desired intervals considering recent developments in sampling and analysis at a fraction of the overall cost of a study.

Etoposide dosage adjustment in two patients with neuroendocrine tumors and severe liver impairment

Introduction

Limited data are available on dosing etoposide in patients with liver impairment.

Case report

We report the dosing strategies for etoposide utilized in two patients with neuroendocrine tumors and severe liver impairment.

Management and outcomes

Treatment consisted of platinum-based chemotherapy regimens, with the decision of whether to administer etoposide and at what doses being based on the liver function before each chemotherapy cycle. By the end of treatment, total bilirubin was normal, and the performance status of both patients had improved, with stable computed tomography scan findings.

Discussion

The reported two cases suggest that the administration of etoposide at reduced doses with close monitoring in patients with neuroendocrine tumors and severe liver impairment may still be considered as an option and may improve outcomes.

Significance of biopsy with ERCP for diagnosis of bile duct invasion of DLBCL

Obstructive jaundice is an initial symptom in 1-2% of diffuse large B cell lymphoma (DLBCL) cases. The major cause of bile duct obstruction in patients with DLBCL is extrinsic compression by enlarged lymph nodes. In such cases, the existence of bile duct invasion of lymphoma is rarely mentioned or observed pathologically, so the ratio of bile duct invasion to the total cases of obstructive jaundice, and its significance remains unknown. We report two cases of DLBCL presenting as an obstructive jaundice, in which we demonstrated bile duct invasion pathologically by biopsy from the wall of common bile duct with endoscopic retrograde cholangiopancreatography (ERCP). Endoscopic stent placement is a minimally invasive procedure to relieve cholestasis and is effective for diagnosing bile duct invasion. This procedure should thus be performed in all cases of obstructive jaundice caused by lymphoma to evaluate for bile duct invasion. Our cases suggest that ERCP may be useful as a diagnostic procedure for bile duct invasion.

Taurine zinc solid dispersions attenuate doxorubicin-induced hepatotoxicity and cardiotoxicity in rats

The clinical efficacy of anthracycline anti-neoplastic agents is limited by cardiac and hepatic toxicities. The aim of this study was to assess the hepatoprotective and cardioprotective effects of taurine zinc solid dispersions, which is a newly-synthesized taurine zinc compound, against doxorubicin-induced toxicity in Sprague-Dawley rats intraperitoneally injected with doxorubicin hydrochloride (3mg/kg) three times a week (seven injections) over 28 days. Hemodynamic parameters, levels of liver toxicity markers and oxidative stress were assessed. Taurine zinc significantly attenuated the reductions in blood pressure, left ventricular pressure and ± dp/dtmax, increases in serum alanine aminotransferase and aspartate aminotransferase activities, and reductions in serum Zn(2+) and albumin levels (P<0.05 or 0.01) induced by doxorubicin. In rats treated with doxorubicin, taurine zinc dose-dependently increased liver superoxide dismutase activity and glutathione concentration, and decreased malondialdehyde level (P<0.01). qBase(+) was used to evaluate the stability of eight candidate reference genes for real-time quantitative reverse-transcription PCR. Taurine zinc dose-dependently increased liver heme oxygenase-1 and UDP-glucuronyl transferase mRNA and protein expression (P<0.01). Western blotting demonstrated that taurine zinc inhibited c-Jun N-terminal kinase phosphorylation by upregulating dual-specificity phosphoprotein phosphatase-1. Additionally, taurine zinc inhibited cardiomyocyte apoptosis as there was decreased TUNEL/DAPI positivity and protein expression of caspase-3. These results indicate that taurine zinc solid dispersions prevent the side-effects of anthracycline-based anticancer therapy. The mechanisms might be associated with the enhancement of antioxidant defense system partly through activating transcription to synthesize endogenous phase II medicine enzymes and anti-apoptosis through inhibiting JNK phosphorylation.

Preparative regimen dosing for hematopoietic stem cell transplantation in patients with chronic hepatic impairment: analysis of the literature and recommendations

Hematopoietic stem cell transplantation (HSCT) is a potentially life-saving therapy for patients with malignant and nonmalignant disease states. Transplant has been associated with high treatment-related morbidity and mortality, therefore limiting its usefulness in patients with baseline liver dysfunction. In the event that a patient with hepatic insufficiency is selected for HSCT, dosage adjustments may be considered; however, no reliable endogenous biomarkers can serve as a guide for adjustments. There is no clear standard or guideline for how to approach these patients, and most adjustments are made empirically on the basis of expert opinion. This article offers practical advice and outlines our personal approaches to provide dosing recommendations for commonly-used preparative agents in the setting of hepatic impairment with the aim to optimize dosing for this patient population.

Outcomes in lymphoma patients with obstructive jaundice: a cancer center experience

BACKGROUND

Little information is available to guide clinicians on the optimal approach to managing obstructive jaundice in lymphoma patients.

AIMS

The aim of this study was to review our experience in treating lymphoma patients with obstructive jaundice in order to develop guidelines as to the best interventional approach.

METHODS

We reviewed the medical records of all lymphoma patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) and/or percutaneous biliary drainage (PBD) for obstructive jaundice between June 2002 and October 2008.

RESULTS

We identified 35 lymphoma patients who underwent ERCP and/or PBD for obstructive jaundice. The mean age was 57.6 years. Most patients (66%) had diffuse large B-cell lymphoma. Stents were placed by ERCP in 25 patients and PBD in nine. Serum bilirubin levels normalized following ERCP or PBD in 29 of 33 (85%) patients with stricture. Stricture resolution occurred in 12 cases. Patients who had obstructive jaundice at the time of their lymphoma diagnosis had significantly longer mean overall survival following intervention than patients in whom obstructive jaundice developed later in the course of their disease (21.3 months vs. 4.5 months, P = 0.0001).

CONCLUSIONS

ERCP and/or PBD effectively normalized serum bilirubin levels. Plastic stents should be used in patients who have obstructive jaundice at the time of lymphoma diagnosis because these strictures tend to resolve before stent exchanges are necessary. For patients in whom obstructive jaundice develops later in the course of their disease, the limited prognosis often makes a single intervention with insertion of a plastic stent sufficient to provide adequate biliary decompression.

How to manage medications in the setting of liver disease with the application of six questions

OBJECTIVE

Reviewing the current literature to guide clinicians managing medications in the setting of liver disease.

LITERATURE SOURCES

Using the terms liver disease, medication management, and therapeutic monitoring, a literature review was conducted to identify peer-reviewed articles in MEDLINE (1966-April 2009). Reference citations were reviewed as an additional resource. Published English-language literatures, articles and trials were reviewed. Emphasis was placed on prospective, randomised, double-blind, placebo-controlled clinical trials.

QUESTION SYNTHESIS

An informed decision on how to manage medications in the setting of liver disease should account for changes that transpire in a medication's first-pass metabolism, protein binding, volume of distribution, clearance and pharmacodynamic interactions. To incorporate these issues within one's thought process, clinicians can utilise the following six questions to evaluate a medication use: (i) Is the patient experiencing acute or chronic liver failure? (ii) Does the drug have high hepatic first-pass metabolism? (iii) Is the medication highly protein-bound? (iv) Is there a change in the volume of distribution for the medication? (v) Is the clearance of the medication significantly altered? and (vi) Is there a pharmacodynamic interaction with the medication?

CONCLUSIONS

The introduction and use of six clinically relevant questions in the setting of liver disease can serve as a guide to clinicians who manage patients with liver disease.

Pharmacokinetics and dosage adjustment in patients with hepatic dysfunction

The liver plays a central role in the pharmacokinetics of the majority of drugs. Liver dysfunction may not only reduce the blood/plasma clearance of drugs eliminated by hepatic metabolism or biliary excretion, it can also affect plasma protein binding, which in turn could influence the processes of distribution and elimination. Portal-systemic shunting, which is common in advanced liver cirrhosis, may substantially decrease the presystemic elimination (i.e., first-pass effect) of high extraction drugs following their oral administration, thus leading to a significant increase in the extent of absorption. Chronic liver diseases are associated with variable and non-uniform reductions in drug-metabolizing activities. For example, the activity of the various CYP450 enzymes seems to be differentially affected in patients with cirrhosis. Glucuronidation is often considered to be affected to a lesser extent than CYP450-mediated reactions in mild to moderate cirrhosis but can also be substantially impaired in patients with advanced cirrhosis. Patients with advanced cirrhosis often have impaired renal function and dose adjustment may, therefore, also be necessary for drugs eliminated by renal exctretion. In addition, patients with liver cirrhosis are more sensitive to the central adverse effects of opioid analgesics and the renal adverse effects of NSAIDs. In contrast, a decreased therapeutic effect has been noted in cirrhotic patients with beta-adrenoceptor antagonists and certain diuretics. Unfortunately, there is no simple endogenous marker to predict hepatic function with respect to the elimination capacity of specific drugs. Several quantitative liver tests that measure the elimination of marker substrates such as galactose, sorbitol, antipyrine, caffeine, erythromycin, and midazolam, have been developed and evaluated, but no single test has gained widespread clinical use to adjust dosage regimens for drugs in patients with hepatic dysfunction. The semi-quantitative Child-Pugh score is frequently used to assess the severity of liver function impairment, but only offers the clinician rough guidance for dosage adjustment because it lacks the sensitivity to quantitate the specific ability of the liver to metabolize individual drugs. The recommendations of the Food and Drug Administration (FDA) and the European Medicines Evaluation Agency (EMEA) to study the effect of liver disease on the pharmacokinetics of drugs under development is clearly aimed at generating, if possible, specific dosage recommendations for patients with hepatic dysfunction. However, the limitations of the Child-Pugh score are acknowledged, and further research is needed to develop more sensitive liver function tests to guide drug dosage adjustment in patients with hepatic dysfunction.

Pharmacokinetics and dosage adjustment in patients with hepatic dysfunction

The liver plays a central role in the pharmacokinetics of the majority of drugs. Liver dysfunction may not only reduce the blood/plasma clearance of drugs eliminated by hepatic metabolism or biliary excretion, it can also affect plasma protein binding, which in turn could influence the processes of distribution and elimination. Portal-systemic shunting, which is common in advanced liver cirrhosis, may substantially decrease the presystemic elimination (i.e., first-pass effect) of high extraction drugs following their oral administration, thus leading to a significant increase in the extent of absorption. Chronic liver diseases are associated with variable and non-uniform reductions in drug-metabolizing activities. For example, the activity of the various CYP450 enzymes seems to be differentially affected in patients with cirrhosis. Glucuronidation is often considered to be affected to a lesser extent than CYP450-mediated reactions in mild to moderate cirrhosis but can also be substantially impaired in patients with advanced cirrhosis. Patients with advanced cirrhosis often have impaired renal function and dose adjustment may, therefore, also be necessary for drugs eliminated by renal exctretion. In addition, patients with liver cirrhosis are more sensitive to the central adverse effects of opioid analgesics and the renal adverse effects of NSAIDs. In contrast, a decreased therapeutic effect has been noted in cirrhotic patients with beta-adrenoceptor antagonists and certain diuretics. Unfortunately, there is no simple endogenous marker to predict hepatic function with respect to the elimination capacity of specific drugs. Several quantitative liver tests that measure the elimination of marker substrates such as galactose, sorbitol, antipyrine, caffeine, erythromycin, and midazolam, have been developed and evaluated, but no single test has gained widespread clinical use to adjust dosage regimens for drugs in patients with hepatic dysfunction. The semi-quantitative Child-Pugh score is frequently used to assess the severity of liver function impairment, but only offers the clinician rough guidance for dosage adjustment because it lacks the sensitivity to quantitate the specific ability of the liver to metabolize individual drugs. The recommendations of the Food and Drug Administration (FDA) and the European Medicines Evaluation Agency (EMEA) to study the effect of liver disease on the pharmacokinetics of drugs under development is clearly aimed at generating, if possible, specific dosage recommendations for patients with hepatic dysfunction. However, the limitations of the Child-Pugh score are acknowledged, and further research is needed to develop more sensitive liver function tests to guide drug dosage adjustment in patients with hepatic dysfunction.

Cancer chemotherapy II: atypical hepatic injuries

Although chemotherapy generally is accompanied by regular testing for liver enzyme abnormalities, atypical reactions may occur that escape ordinary detection, because hepatocyte injury is not the primary event. The presence of fatty liver, mitochondrial changes, and even biliary abnormalities can be associated with normal or nearly normal liver enzyme levels. This article discusses unique aspects of liver damage associated with cancer chemotherapy. These unique reactions merit special attention and a special vigilance from clinicians.