Annals of Gastroenterology & Hepatology Vol I Issue 2

Preoperative Biliary Stents in Pancreatic Cancer

Pancreatic cancer is a common disease and surgical resection is the only potential curative treatment option. Biliary obstruction nearly always occurs in patients with cancer of the pancreatic head. Because obstructive jaundice potentially increases surgical complications following pancreaticoduodenectomy, preoperative biliary drainage has been advocated. Endoscopic and percutaneous stent placement techniques have been used and in experienced centers the technical success rates for biliary decompression are high. Routine preoperative biliary drainage for obstructive jaundice and pancreatic cancer is controversial. Prospective studies have demonstrated that complications related to preoperative biliary drainage using traditional plastic endoprostheses increases the morbidity following pancreaticoduodenectomy. Self-expandable metal stents provide longer patency than traditional plastic stents and could reduce stent-related complication rates following preoperative biliary decompression, especially when surgery is delayed. Selected patients with deep jaundice, those in need of neoadjuvant treatment prior to curative intent surgery, are the candidates who benefit most from temporary biliary drainage. Patients with pancreatic cancer presenting with cholangitis need early, urgent preoperative biliary decompression.

Advances in Biliary Imaging

Noninvasive imaging of the biliary tree has undergone substantial technological innovation over the past two decades and has led to increased usage in the diagnostic evaluation of suspected biliary tract pathology. While endoscopic retrograde cholangiopancreatography has been regarded as the gold standard for diagnostic evaluation of the pancreaticobiliary tree and offers the benefit of therapeutic intervention, technical failure and complications rates are not insignificant. Multidetector computed tomography (CT) and magnetic resonance imaging (MRI) can depict the biliary tree with high technical success and minimal procedural risk. The development of helical scanning technique and multidetector technology has revolutionized CT, allowing volumetric data acquisition with sub-millimeter voxels. Evaluation of the biliary tree by MRI relies on one of several available magnetic resonance cholangiopancreatography (MRCP) protocols, which offer superior contrast resolution versus CT. Thick slab single-section and thin slice multi-section techniques provide satisfactory complementary techniques that can obtained very quickly, including in uncooperative patients. Recent innovations in MRI sequence design and scanner technology have resulted in improved MRCP techniques, including newer 3D T2-weighted techniques and high field strength imaging at 3.0 Tesla. Newer contrast agents excreted into the hepatobiliary tree may provide a valuable adjunct to patients undergoing liver MRI for other reasons, including preoperative transplant evaluation or suspected postoperative complication. The diagnostic performance of both CT and MRI has been proven for many biliary clinical applications, including calculi, strictures, and tumor staging.

Gadoxetic Acid-Enhanced MRI Compared with Unspecific Extracellular Contrast Media for Differential Diagnosis of Metastasis and Benign Liver Lesions

Extracellular space gadolinium-based contrast media (ECCM) were considered as the standard in contrast-enhanced liver MRI since the early nineties. ECCM increase the accuracy of focal lesion detection and characterization by providing perfusion information with temporal resolution, typically in arterial, portal venous, and equilibrium phases.

With the focus to further increase the accuracy of lesion detection, different liver-specific contrast media were developed and approved. The first generation of this group was not bolus injectable, thereby reducing the potential for focal lesion characterization because of the missing possibility to access the dynamics in lesion perfusion. The recently approved Gd-based contrast medium gadoxetic acid (Primovist†, Bayer Healthcare, Germany) combines the perfusion characteristics of ECCM with a high hepatocyte-specific uptake 10-20 minutes after administration. Gadoxetic acid has proven similar enhancement characteristics in the early perfusion phases compared with ECCM and contrast-enhanced CT. In addition, information about possible hepatocyte-selective uptake in lesions helps to identify lesions of hepatocellular origin and, therefore, offers valuable molecular information for characterization of focal lesions.

For differential diagnosis between metastasis and benign liver lesions, including liver cysts, hemangiomas, and other more uncommon benign liver lesions, gadoxetic acid offers additional useful functional information about hepatocytic uptake, thereby increasing the confidence for lesion characterization, allowing more accurate therapy planning and reducing the need for lesion biopsies. Gadoxetic acid represents the highest standard for non-invasive metastasis identification and reliable differential from typical benign liver lesion.

The Value of Gadoxetic Acid-Enhanced Hepatospecific Phase MR Imaging for Characterization of Hepatocellular Nodules in the Cirrhotic Liver

INTRODUCTION

Owing to significant overlaps between the dynamic imaging findings of dysplastic nodule (DN) and hepatocellular carcinoma (HCC) in cirrhotic livers, we investigated the added value of gadoxetic acid MR imaging, which combines dynamic and hepatospecific properties.

OBJECTIVES

The purpose of this study is to retrospectively assess the value of adding hepatospecific phase images of gadoxetic acid enhanced MR imaging to unenhanced and dynamic enhanced MR images for the characterization of HCC and DN in patients with cirrhosis.

METHODS

A total of 34 patients with 39 HCCs and 15 DNs were enrolled and all lesions were pathologically proved except for 16 HCCs. Patients underwent gadoxetic acid enhanced MR examination, including dynamic and 20 min hepatospecific phase imaging using a 1.5-Tesla system. Two radiologists independently reviewed two sets of MR images: set A, unenhanced (T1- and T2-weighted) and gadoxetic acid enhanced dynamic images; set B, unenhanced (T1- and T2-weighted) and gadoxetic acid enhanced dynamic images plus 20 min hepatospecific phase images. For each set and each observer, the diagnostic accuracy was compared using ROC curve analysis (Az). Sensitivity and specificity values were also calculated.

RESULTS

For both observers, Az values for the diagnosis of HCC resulted to be higher with the addition of hepatospecific phase images, with a significant improvement for the less experienced observer (p=.045). Similarly, sensitivity values significantly increased with the addition of hepatospecific phase images for both observers (p=.044 for observer 1 and p=.025 for observer 2). No significant differences were observed for specificity values.

CONCLUSION

Adding the hepatospecific phase to unenhanced and dynamic gadoxetic acid enhanced MR images helps to differentiate HCC from DN.

Colorectal Carcinoma Complicating Inflammatory Bowel Disease

Patients with inflammatory bowel disease (IBD) are at increased risk for developing colorectal carcinoma (CRC). It accounts for approximately 10–15% of all deaths in IBD patients. The magnitude of the increased risk as well as how to mitigate it best remain a topic of ongoing investigation in the field. Strategies to reduce or prevent the complications associated with invasive cancer are essential in this high-risk population. Surveillance colonoscopies are an important strategy to detect CRC and dysplasia at an early stage and thereby decrease CRC-related morbidity and mortality. This article will review the clinical characteristics of IBD-related CRC as well as the epidemiology as the evidence and rationale behind consensus guidelines for screening and surveillance.

The Prevention of Cytomegalovirus after Liver Transplantation

Cytomegalovirus is a common viral pathogen that can negatively influence the outcome after liver transplantation. The immunocompromised liver transplant population is at an increased risk for developing clinically significant disease. Most cytomegalovirus infections in the liver transplant population are caused by reactivation of latent virus of either donor or recipient origin. Once infected with cytomegalovirus, it can lead to a host of direct effects, which can virtually affect any organ, as well as indirect effects such as an increased predisposition to rejection and opportunistic infections. These direct and indirect effects can lead to increased morbidity and mortality in the transplant recipient. Therefore, cytomegalovirus prevention after liver transplant is an essential component in the management of this population. This review will provide an overview of cytomegalovirus in the liver transplant recipient, while focusing on cytomegalovirus prevention after liver transplantation.

Serum ALT Levels in a Cohort of Healthy Blood Donors and Volunteers from Saudi Arabia: The Influence of Sex and Body Mass Index

Serum alanine aminotransferase (ALT) is the most sensitive biochemical marker of hepatocellular injury. The internationally accepted normal level for ALT is 30 U/L in males and 19 U/L in females. Body mass index (BMI) and sex have a significant influence on the ALT levels.

Outcomes of Ablation versus Resection for Colorectal Liver Metastases

Approximately half of patients with colorectal cancer develop metastasis to the liver, with either a synchronous or metachronous presentation. Complete surgical resection of colorectal liver metastasis (CRLM) offers the best potential for cure and is considered the gold-standard treatment. However, the use of ablative techniques to treat CRLM has gained greater acceptance and is increasingly utilized. While in the past cryoablation was utilized, currently thermo-ablation with either radiofrequency or microwave energy is the preferred approach to ablate CRLM. Data regarding the oncologic outcome of patients treated with ablation versus resection have been ambiguous. Evidence regarding the use and efficacy of ablation for CRLM has largely been derived from retrospective series. Most data suggest that outcomes (ie, overall and disease-free survival) following ablation are worse as compared with hepatic resection. Patients undergoing ablation, however, often have very different clinicopathologic characteristics than patients undergoing resection, making retrospective comparisons difficult to interpret. We herein review the current data on the outcomes of ablation versus resection for CRLM.

A Duodenal Adenocarcinoma with Unpredictable Outcome in a Patient with Compensated Cirrhosis

Small bowel tumors are very rare digestive malignancies, accounting for approximately 1% of all gastrointestinal tumors. A certain predilection has been described for tumor location throughout the entire small intestine taking into account the histological type. Carcinoid tumors typically affect the ileum, sarcomas and lymphomas can develop throughout the entire small bowel, while adenocarcinoma is the most common malignant tumor affecting the duodenum. Unfortunately, duodenal tumors are asymptomatic in early stages, making it difficult to diagnose them under such circumstances. They become symptomatic in advanced cases, when commonly present with intestinal obstruction. We report the case of a male patient with compensated cirrhosis and surgically resected duodenal adenocarcinoma, who developed postoperatory potentially life-threatening complications, like upper and lower gastrointestinal hemorrhage.

Factors Predictive of Erosive versus Nonerosive Esophageal Reflux Disease

BACKGROUND

To date, studies are lacking to determine risk factors for erosive esophagitis versus nonerosive disease. This is important as erosive esophagitis can lead to complications such as bleeding and strictures. Our aim was to identify factors associated with the presence or absence of esophageal erosions in a large group of US patients presenting with gastroesophageal reflux disease symptoms.

METHODS

We reviewed the records of outpatients who underwent endoscopy for symptoms of chronic gastroesophageal reflux. We included patients who had a negative exam if they had a subsequent BRAVO capsule pH study off proton pump inhibitor (PPI) therapy. Results were imputed into an ordinal logistic regression model.

RESULTS

There were 429 patients, with 235 (54.8%) females. The mean age was 51.1±16.1 years. In the final ordinal logistic regression model, smoking OR = 5.23 (95% CI, 2.27–12.06); diabetes 4.95 (95% CI, 2.07–11.88); male gender 2.81 (95% CI, 1.61–4.92); and Black race 5.41 (95% CI, 1.41–20.66) were significantly associated with more severe reflux. The model appeared to be well calibrated; all 23 patients who were Black males that smoked and had diabetes were found to have endoscopic evidence of esophagitis.

CONCLUSIONS

Our study demonstrates that male gender, Black race, smoking, and the presence of diabetes are significantly associated with the presence of erosive esophagitis. We could not identify increasing body mass index as an independent predictor. Our results provide gastroenterologists with useful information as the patient profiles of those more likely to harbor erosions can be used to triage patients for endoscopy.

Interventional Radiology in the Management of Hepatocellular Carcinoma in Liver Cirrhosis

Liver cirrhosis represents the final stage in the spectrum of chronic liver disease and constitutes an important healthcare burden worldwide because of its high morbidity and mortality. Management of hepatocellular carcinoma (HCC) in cirrhotic patients is often challenging because of the presence of underlying liver disease. Image-guided diagnosis and intervention has a crucial role in the surveillance, diagnosis, treatment, and post-treatment follow-up of HCC in these patients. Image-guided biopsy has a dual role, which comprises of non-targeted liver biopsy for diagnosis and staging of cirrhosis and targeted biopsy of nodules suspicious for HCC. Surgical resection and transplantation are deemed curative therapies for treatment of HCC in cirrhosis while percutaneous image-guided ablative techniques are often used to treat patients with non-resectable and non-transplantable disease, as a bridge to transplantation, or with palliative intent. Radiofrequency ablation (RFA) is among the most effective percutaneous ablative technique while ethanol injection is an effective alternative to RFA in treatment of HCCs smaller than 2 cm. Transarterial chemoembolization (TACE) offers a non-curative or palliative therapy for nonsurgical patients with large or multifocal HCC without vascular invasion or extrahepatic disease and prolongs survival in comparison to standard supportive care. There has been an emerging trend to combine TACE with ethanol injection or RFA to reduce recurrence and improve survival in patients with HCC. In this review article we discuss the key concepts in the oncological management of cirrhotic patients from the perspective of the interventional radiologist.