Ductopenia related liver sarcoidosis

Sarcoidosis is a systemic granulomatous disease which may involve many organs. In approximately 95% of patients there is liver involvement, with noncaseating hepatic granulomas occurring in 21 to 99% of patients with sarcoidosis. Liver involvement is usually asymptomatic and limited to mild to moderate abnormalities in liver biochemistry. The occurrence of jaundice in sarcoidosis is rare; extensive imaging procedures and the examination of liver biopsies permit a precise diagnostic. Ductopenia associated with sarcoidosis has been reported in less than 20 cases and can lead to biliary cirrhosis and liver- related death. We report here on a case of ductopenia-related sarcoidosis in which primary biliary cirrhosis and extrahepatic cholestasis have been carefully excluded. The patient follow up was 8 years. Although ursodesoxycholic acid appears to improve liver biochemistry it does not preclude the rapid occurrence of extensive fibrosis. A review of the literature of reported cases of ductopenia related to sarcoidosis is provided.

Budd-Chiari syndrome in a patient with ulcerative colitis and no inherited coagulopathy

We report a case of 27 year old female patient who was admitted to the hospital with an acute flare up of ulcerative colitis. The patient presented with complaints of persistent abdominal pain and bloody diarrhea despite aggressive therapy for her ulcerative colitis. A CT scan of the abdomen on admission revealed hepatic vein thrombosis, suggesting a diagnosis of Budd-Chiari syndrome. Significantly, an associated thrombosis of the inferior mesenteric vein was also detected. Based on imaging data and clinical assessment, the patient was started on anticoagulation therapy and an extensive work-up for hypercoagulability was initiated. Up to the time of publication, no significant findings suggesting this patient has an underlying coagulation disorder have been found. Based on our search of PUBMED, this report is one of only five reported adult cases of Budd-Chiari Syndrome associated with ulcerative colitis in the English literature in living patients without evidence of a co-existing coagulation disorder. This case highlights the potential for thrombosis at unusual sites in ulcerative colitis patients even in the absence of classical coagulation abnormalities. In addition to the case presented, we provide a brief review of previously reported cases of Budd-Chiari Syndrome occurring in patients with inflammatory bowel disease.

Management of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a rare cholestatic liver disease with major morbidity and mortality. Therapeutic management is difficult, due to lack of conclusive data and individual disease progression. High-dose UDCA was used for years as a pharmacotherapeutic agent to prevent disease progression, based on a positive trend in pilot studies, but has recently been proven to have a negative effect in advanced disease. Immunosuppressants might be useful in patients with overlap syndromes. Dominant bile duct stenoses should be treated endoscopically, and cholangiocellular carcinoma (CCC) still remains a therapeutic challenge in PSC patients. Early diagnosis of CCC must be improved and new strategies such as neoadjuvant radiochemotherapy with subsequent liver transplantation in selected patients are further options to be considered.

A key problem and challenge for hepatology: Obesity-related metabolic liver diseases

With the arrival of the new millennium, gastroenterologists have been faced with the problem of metabolic liver diseases associated with obesity. The active role of the liver in metabolism and inflammation make it a key organ in the war against the rapidly-spreading world-wide epidemic of obesity. Many lives and much money could be saved if the work of hepatologists led to the development of effective diagnostic and therapeutic strategies against this growing leader of cirrhosis.

MELD score, insulin-like growth factor 1 and cytokines on bone density in end-stage liver disease

AIM

To determine the contributions of insulin-like growth factor 1 (IGF-1), cytokines and liver disease severity to bone mineral density in patients pre-transplantation.

METHODS

Serum IGF-1, tumor necrosis factor-α (TNFα) and interleukin 6 (IL-6) were measured and the Model for End-Stage Liver Disease (MELD) score calculated in 121 adult patients referred to a single centre for liver transplantation. Bone mineral density (BMD) of the lumbar spine and femoral neck were assessed via dual energy X-ray absorptiometry. Demographics, liver disease etiology, medication use and relevant biochemistry were recorded.

RESULTS

A total of 117 subjects were included, with low BMD seen in 68.6%, irrespective of disease etiology. In multivariable analysis, low body mass index (BMI), increased bone turnover and low IGF-1 were independent predictors of low spinal bone density. At the hip, BMI, IGF-1 and vitamin D status were predictive. Despite prevalent elevations of TNFα and IL-6, levels did not correlate with degree of bone loss. The MELD score failed to predict low BMD in this pre-transplant population.

CONCLUSION

Osteopenia/osteoporosis is common in advanced liver disease. Low serum IGF-1 is weakly predictive but serum cytokine and MELD score fail to predict the severity of bone disease.

HBV vaccine efficacy and detection and genotyping of vaccineé asymptomatic breakthrough HBV infection in Egypt

AIM

To evaluate the impact of mass vaccination against the hepatitis B virus (HBV) in Egypt, and to search for vaccinee asymptomatic breakthrough HBV infection and its genotype.

METHODS

Seven hundred serum samples from vaccinated children and adults (aged 2-47 years) were used for quantitative and qualitative detection of HBsAb by ELISA. Three hundred and sixty serum samples representing undetectable or low or high HBsAb were screened for markers of active HBV infection (HBsAg, HBcAb (IgG) and HBeAb by ELISA, plus HBsAg by AxSYM) and HBV-DNA genotyping by nested multiplex PCR and by DNA sequencing.

RESULTS

It was found that 65% of children aged 2-4 years, and 20.5% aged 4-13 years, as well as 45% adults were good responders to HBV vaccination mounting protective level HBsAb. Poor responders were 28%, 59.5% and 34%, and non-responders were 7%, 20% and 21% respectively, in the three studied groups. Markers of asymptomatic HBV infections were HBsAg detected by ELISA in 2.5% vs 11.39% by AxSYM. Other markers were HBcAb (IgG) in 1.38%, HBeAb in 0.83%, and HBV-DNA in 7.8%. All had HBV genotype E infection.

CONCLUSION

It is concluded that HBV vaccine is efficient in controlling HBV infection among children and adults. The vaccine breakthrough infection was by HBV genotype E. A booster dose of vaccine is recommended, probably four years after initial vaccination.

Pathogenesis of alcoholic hepatitis: Role of inflammatory signaling and oxidative stress

Inflammatory signaling and oxidative stress are two major components in the pathogenesis of alcoholic hepatitis. Alcohol consumption results in translocation of gut bacteria into the portal system along with lipopolysaccharides that interact with toll-like receptors and results in the production of inflammatory and immunogenic mediators such as tumor necrosis factor-alpha (TNF-α) and interferons. Chronic consumption of alcohol causes priming of this process in which there is enhanced production of cytokines, interferon, interleukins, and TNF-α. Oxidative stress, genetic predisposition, and the unfolded protein response are other contributory mechanisms. Novel therapies aimed at these pathways may prevent, decrease, or delay the complications of alcoholic hepatitis.

Acute renal dysfunction in patients with alcoholic hepatitis

Acute renal dysfunction is common in patients with alcoholic hepatitis (AH). Its presence leads to higher mortality in these patients. Despite advances in medical care, the outcome has changed little over the past decades. Studies using Pentoxifylline and molecular adsorbent recirculation system have shown encouraging data in small studies. Further larger well designed studies are needed to assess these modalities of treatment for the treatment of AH.

Definition, epidemiology and magnitude of alcoholic hepatitis

Alcoholic liver disease (ALD) is a major cause of alcohol-related morbidity and mortality. Its presentation ranges from fatty liver to alcoholic hepatitis (AH), cirrhosis, and hepatocellular carcinoma. Although the amount and pattern of alcohol consumption is a well recognized predisposing factor for the development of serious liver pathology, environmental factors and the host's genetic make-up may also play significant roles that have not yet been entirely explored. Continuing alcohol consumption is a major factor that influences the survival of patients with AH. The presence of cirrhosis at presentation or its development on follow up is a major factor determining the outcome in the long run. This chapter deals with the epidemiology and magnitude of ALD in general and AH in particular.

Bacteremia and "Endotipsitis" following transjugular intrahepatic portosystemic shunting

AIM

To identify all cases of bacteremia and suspected endotipsitis after Transjugular intrahepatic portosystemic shunting (TIPS) at our institution and to determine risk factors for their occurrence.

METHODS

We retrospectively reviewed records of all patients who underwent TIPS in our institution between 1996 and 2009. Data included: indications for TIPS, underlying liver disease, demographics, positive blood cultures after TIPS, microbiological characteristics, treatment and outcome.

RESULTS

49 men and 47 women were included with a mean age of 55.8 years (range 15-84). Indications for TIPS included variceal bleeding, refractory ascites, hydrothorax and hepatorenal syndrome. Positive blood cultures after TIPS were found in 39/96 (40%) patients at various time intervals following the procedure. Seven patients had persistent bacteremia fitting the definition of endotipsitis. Staphylococcus species grew in 66% of the positive cultures, Candida and enterococci species in 15% each of the isolates, and 3% cultures grew other species. Multi-variate regression analysis identified 4 variables: hypothyroidism, HCV, prophylactic use of antibiotics and the procedure duration as independent risk factors for positive blood cultures following TIPS (P < 0.0006, 0.005, 0.001, 0.0003, respectively). Prophylactic use of antibiotics before the procedure was associated with a decreased risk for bacteremia, preventing mainly early infections, occurring within 120 d of the procedure.

CONCLUSION

Bacteremia is common following TIPS. Risk factors associated with bacteremia include failure to use prophylactic antibiotics, hypothyroidism, HCV and a long procedure. Our results strongly support the use of prophylaxis as a means to decrease early post TIPS infections.

General aspects of the treatment of alcoholic hepatitis

General measures for treating patients with alcoholic hepatitis (AH) are similar irrespective of the disease severity. Alcohol abstinence is the cornerstone of treatment and can be achieved with appropriate social support, Alcoholics Anonymous and sometimes pharmacological therapy. Alcohol withdrawal should be anticipated and treatment initiated to prevent this complication. Treatment for complications of cirrhosis should be as for any other patient with cirrhosis. AH patients are particularly prone to infections and malnutrition. These should be identified and treated appropriately using broad spectrum antibiotics and nutritional support respectively.

Symptoms and signs of acute alcoholic hepatitis

Although there is not one specific sign or symptom related to alcoholic hepatitis (AH), a constellation of symptoms and signs can help make the diagnosis of AH with reasonable accuracy. Documentation of chronic and active alcohol abuse is paramount in making a diagnosis of AH. Clinical presentation after abstinence for more than 3 m should raise doubts about the diagnosis of AH and dictate the need for considering other causes of liver disease, decompensation of alcoholic cirrhosis, sepsis and malignancy as the cause of patient's clinical profile.

Insulin resistance and chronic liver disease

Increased insulin resistance is frequently associated with chronic liver disease and is a pathophysiological feature of hepatogenous diabetes. Distinctive factors including hepatic parenchymal cell damage, portal-systemic shunting and hepatitis C virus are responsible for the development of hepatogenous insulin resistance/diabetes. Although it remains unclear whether insulin secretion from pancreatic beta cells is impaired as it is in type 2 diabetes, retinopathic and cardiovascular risk is low and major causes of death in cirrhotic patients with diabetes are liver failure, hepatocellular carcinoma and gastrointestinal hemorrhage. Hemoglobin A1c is an inaccurate marker for the assessment and management of hepatogenous diabetes. Moreover, exogenous insulin or sulfonylureas may be harmful because these agents may promote hepatocarcinogenesis. Thus, pathogenesis, cause of death, assessment and therapeutic strategy for hepatogenous insulin resistance/diabetes differ from those for lifestyle-related type 2 diabetes. In this article, we review features of insulin resistance in relationship to chronic liver disease. We also discuss the impact of anti-diabetic agents on interferon treatment and hepatocarcinogenesis.

Asymptomatic primary biliary cirrhosis is not associated with increased frequency of cardiovascular disease

AIM

To estimate the prevalence of cardiovascular events in Primary biliary cirrhosis (PBC) and to determine whether this risk is higher within specific subgroups of patients with PBC.

METHODS

We included 180 patients with PBC (cases) and 151 patients seen for HCV infection (controls). Medical records were reviewed and statistical analyses were performed as appropriate.

RESULTS

When compared to controls, PBC patients were older, leaner and had higher serum levels of total cholesterol, high density lipoprotein and low density cholesterol. There were more females in the PBC group (91.7% vs 43%, P < 0.001). More control subjects had smoked than the PBC patients (63.6% vs 35%, P < 0.001). The prevalence of hypertension, diabetes, coronary artery disease and stroke was similar between the two groups. Seven percent of controls and 10% of cases developed any type of cardiovascular disease (P = 0.3). Only 36.7% were asymptomatic at diagnosis. Three cardiovascular events were documented among asymptomatic patients (4.5%) and fifteen among symptomatic patients (13.2%; P = 0.06). Among PBC patients with fatigue, 10 (13.5%) had a cardiovascular event compared to 7 (6.7%) among patients without fatigue (P = 0.1).

CONCLUSION

Asymptomatic PBC patients do not have a greater frequency of cardiovascular disease; nor do patients suffering with fatigue.

Infections in liver transplant recipients

Liver transplantation is a standard life-saving procedure for the treatment of many end-stage liver diseases. The success of this procedure may be limited by infectious complications. In this article, we review the contemporary state of infectious complications during the post-operative period, with particular emphasis on those that occur most commonly during the first 6 mo after liver transplantation. Bacteria, and less commonly Candida infections, remain the predominant pathogens during the immediate post-operative period, especially during the first month, and infections caused by drug-resistant strains are emerging. Infections caused by cytomegalovirus and Aspergillus sp. present clinically during the "opportunistic" period characterized by intense immunosuppression. As newer potent immunosuppressive therapies with the major aim of reducing allograft rejection are developed, one potential adverse effect is an increase in certain infections. Hence, it is essential for liver transplant centers to have an effective approach to prevention that is based on predicted infection risk, local antimicrobial resistance patterns, and surveillance. A better understanding of the common and most important infectious complications is anticipated to lead to improvements in quality of life and survival of liver transplant recipients.

Multi-organ failure with atypical liver granulomas following intravesical Bacillus Calmette-Guerin instillation

Bacillus Calmette-Guerin (BCG) intravesical instillation has been adopted in the treatment of patients with superficial bladder cancer. BCG-induced disseminated infection, though rare, has been associated with the histological finding of epithelioid granulomas in different organs, including the liver. We report the case of an adult patient with multi-organ failure, who developed sepsis, acute respiratory failure and acute hepatic failure with encephalopathy whose liver biopsy confirmed the presence of atypical, granulomatous-like lesions. Recovery was observed only after empirical therapy for Mycobacterium bovis with isoniazid, rifampicin, ethambutol and steroids was introduced. This case highlights the importance of a thorough patient assessment in order to exclude other more common causes of hepatic granulomas and to confirm diagnosis. Histological findings may be non-specific when the liver is involved in BCG-induced disseminated infection.

Intensive care management of liver transplanted patients

Advances in pre-transplant treatment of cirrhosis-related organ dysfunction, intraoperative patient management, and improvements in the treatment of rejection and infections have made human liver transplantation an effective and valuable option for patients with end stage liver disease. However, many important factors, related both to an increasing "marginality" of the implanted graft and unexpected perioperative complications still make immediate post-operative care challenging and the early outcome unpredictable. In recent years sicker patients with multiple comorbidities and organ dysfunction have been undergoing Liver transplantation; appropriate critical care management is required to support prompt graft recovery and prevent systemic complications. Early post-operative management is highly demanding as significant changes may occur in both the allograft and the "distant" organs. A functioning transplanted liver is almost always associated with organ system recovery, resulting in a new life for the patient. However, in the unfortunate event of graft dysfunction, the unavoidable development of multi-organ failure will require an enhanced level of critical care support and a prolonged ICU stay. Strict monitoring and sustainment of cardiorespiratory function, frequent assessment of graft performance, timely recognition of unexpected complications and the institution of prophylactic measures to prevent extrahepatic organ system dysfunction are mandatory in the immediate post-operative period. A reduced rate of complications and satisfactory outcomes have been obtained from multidisciplinary, collaborative efforts, skillful vigilance, and a thorough knowledge of pathophysiologic characteristics of the transplanted liver.

Polymorphisms in programmed death-1 gene are not associated with chronic HBV infection in Chinese patients

AIM

To investigate the association between the programmed death-1(PD-1) polymorphisms and genetic susceptibility of chronic hepatitis B virus (HBV) infection in Chinese patients.

METHODS

Two single nucleotide polymorphisms (SNPs), PD-1.1 G > A and PD-1.2 G > A, were genotyped in 539 patients with chronic HBV infection and 353 other family members (HbsAg-) from 256 nuclear families using polymerase chain reactiorestriction fragment length polymorphisms assay. The associations between PD-1 polymorphisms and genetic susceptibility of chronic HBV infection were analyzed usng the family-based association analysis method.

RESULTS

No association or linkage was detected among 539 patients. Univariate (single-marker) family-based association tests demonstrated that PD-1 genotypes, alleles and transmitted haplotypes are not associated with chronic HBV infection (all with P value more than 0.05). Transmission/disequilibrium test and sibship disequilibrium test analysis showed no excess of the alleles from heterozygous parents to affected offspring (P = 0.688880, P = 1.000000 respectively).

CONCLUSION

The data demonstrated that PD-1.1 and PD-1.2 polymorphisms are not associated with chronic HBV infection in Chinese patients.

Hepatitis B prevention and control: Lessons from the East and the West

Despite being ten times more common than HIV infection, viral hepatitis has so far not commanded the same public health response worldwide, so a global viral hepatitis treatment program is still a long way from becoming a reality. However, much progress has occurred over the last few decades, with the screening of blood products, sound infection control practices and the introduction of disposable needles and syringes leading to significant reductions in nosocomial hepatitis B transmission in the developed world and increasingly in other countries. The introduction of hepatitis B vaccination in the 1980s and its integration into the Expanded Immunization Program have led to substantial reductions in chronic hepatitis B infection rates in children and to millions of lives saved. The availability of effective antiviral treatment has revolutionized treatment prospects, although access to treatment remains a significant challenge for most developed countries and remains out of reach for developing nations. Some of these breakthroughs have occurred in Asian countries, others in the West, but their unifying features are innovative research, timely clinical translation and a commitment to apply their findings to improve the health of populations, not just individuals. This paper reviews some of the challenges and opportunities for hepatitis B control at the end of the first decade of the third millennium and argues for closer East - West collaborations, to bring in fresh perspectives, avoid duplications of effort and in order to help answer many of the remaining challenges in making hepatitis B history.

A mutation of the start codon in the X region of hepatitis B virus DNA in a patient with non-B, non-C chronic hepatitis

There are cases of hepatitis involving occult hepatitis B virus (HBV) infection in which, even though the HB surface antigen (HBsAg) is negative, HBV-DNA is detected by a polymerase chain reaction (PCR). We conducted a sequence analysis of the entire HBV region in a case of non-B non-C chronic hepatitis in a 46-year-old female. A diagnosis of non-B non-C chronic hepatitis was made. Although HBV markers, such as HBs antibody (anti-HBs), anti-HBc, HBeAg and anti-HBe, were negative, HBV-DNA was positive. Nested PCR was performed to amplify the precore region of HBV-DNA and all remaining regions by long nested PCR. Sequence analysis of the two obtained bands was conducted by direct sequencing. Compared with the control strains, the ATG (Methionine) start codon in the X region had mutated to GTG (Valine). It is assumed that a mutation at the start codon in the X region may be the reason why HBV markers are negative in some cases of hepatitis that involve occult HBV infection.

Cellular fibronectin stimulates hepatocytes to produce factors that promote alcohol-induced liver injury

AIM

To examine the consequences of cellular fibronectin (cFn) accumulation during alcohol-induced injury, and investigate whether increased cFn could have an effect on hepatocytes (HCs) by producing factors that could contribute to alcohol-induced liver injury.

METHODS

HCs were isolated from rats fed a control or ethanol liquid diet for four to six weeks. Exogenous cFn (up to 7.5 μg/mL) was added to cells cultured for 20 h, and viability (lactate dehydrogenase,LDH), apoptosis (caspase activity) and secretion of proinflammatory cytokines (tumor necrosis factor alpha, TNF-α and interleukin 6 IL-6), matrix metalloproteinases (MMPs) and their inhibitors (tissue inhibitors of metalloproteinases, TIMPs) was determined. Degradation of iodinated cFn was determined over a 3 h time period in the preparations.

RESULTS

cFn degradation is impaired in HCs isolated from ethanol-fed animals, leading to its accumulation in the matrix. Addition of exogenous cFn did not affect viability of HCs from control or ethanol-fed animals, and apoptosis was affected only at the higher concentration. Secretion of MMPs, TIMPs, TNF-α and IL-6, however, was increased by exogenously added cFn, with HCs from ethanol-fed animals showing increased susceptibility compared to the controls.

CONCLUSION

These results suggest that the elevated amounts of cFn observed in alcoholic liver injury can stimulate hepatocytes to produce factors which promote further tissue damage.

Liver cancer: Targeted future options

Hepatocellular carcinoma (HCC) has a poor prognosis and systemic chemotherapies have disappointing results. The increasing knowledge of the molecular biology of HCC has resulted in novel targets, with the vascular endothelial growth factor and epidermal growth factor receptor (EGFR)-related pathways being of special interest. New blood vessel formation (angiogenesis) is essential for the growth of solid tumors. Anti-angiogenic strategies have become an important therapeutic modality for solid tumors. Several agents targeting angiogenesis-related pathways have entered clinical trials or have been already approved for the treatment of solid tumors. These include monoclonal antibodies, receptor tyrosine kinase inhibitors and immunomodulatory drugs. HCC is a highly vascular tumor, and angiogenesis is believed to play an important role in its development and progression. This review summarizes recent advances in the basic understanding of the role of angiogenesis in HCC as well as clinical trials with novel therapeutic approaches targeting angiogenesis and EGFR-related pathways.

Multicentric occurrence of hepatocellular carcinoma with nonalcoholic steatohepatitis

AIM

To reveal the manner of hepatocellular carcinoma (HCC) development in patients with nonalcoholic steatohepatitis (NASH) focusing on multicentric occurrence (MO) of HCC.

METHODS

We compared clinicopathological characteristics between patients with and without MO of HCC arising from NASH background. The clinical features were implicated with reference to the literature available.

RESULTS

MO of HCC was identified with histological proof in 4 out of 12 patients with NASH-related HCC (2 males and 2 females). One patient had synchronous MO; an advanced HCC, two well-differentiated HCCs and a dysplastic nodule, followed by the development of metachronous MO of HCC. The other three patients had multiple advanced HCCs accompanied by a well-differentiated HCC or a dysplastic nodule. Of these three patients, one had synchronous MO, one had metachronous MO and the other had both synchronous and metachronous MO. There were no obvious differences between the patients with or without MO in terms of liver function tests, tumor markers and anatomical extent of HCC. On the other hand, all four patients with MO of HCC were older than 70 years old and had the comorbidities of obesity, type 2 diabetes mellitus (T2DM), hypertension and cirrhosis. Although these conditions were not limited to MO of HCC, all the conditions were met in only one of eight patients without MO of HCC. Thus, concurrence of these conditions may be a predisposing situation to synchronous MO of HCC. In particular, old age, T2DM and cirrhosis were suggested to be prerequisite for MO because these factors were depicted in common among two other cases with MO of HCC under NASH in the literature.

CONCLUSION

The putative predisposing factors and necessary preconditions for synchronous MO of HCC in NASH were suggested in this study. Further investigations are required to clarify the accurate prevalence and predictors of MO to establish better strategies for treatment and prevention leading to the prognostic improvement in NASH.

Genetic susceptibility to autoimmune liver disease

Autoimmune hepatitis (AIH), primary sclerosing cholangitis (PSC) and primary biliary cirrhosis (PBC) are considered as putative autoimmune diseases of the liver. Whereas strong evidence that bacterial infection may trigger PBC exists, the etiologies for PSC and AIH remain unknown. Although there have been significant discoveries of genetic polymorphisms that may underlie the susceptibility to these liver diseases, their associations with environmental triggers and the subsequent implications have been difficult to elucidate. While single nucleotide polymorphisms within the negative costimulatory molecule cytotoxic T lymphocyte antigen 4 (CTLA-4) have been suggested as genetic susceptibility factors for all three disorders, we discuss the implications of CTLA-4 susceptibility alleles mainly in the context of PBC, where Novosphingobium aromaticivorans, an ubiquitous alphaproteobacterium, has recently been specifically associated with the pathogenesis of this devastating liver disease. Ultimately, the discovery of infectious triggers of PBC may expand the concept of genetic susceptibility in immune-mediated liver diseases from the concept of aberrant immune responses against self-antigens to insufficient and/or inappropriate immunological defense mechanisms allowing microbes to cross natural barriers, establish infection and damage respective target organs.

Radiofrequency ablation of liver tumors: Actual limitations and potential solutions in the future

Over the past decade, radiofrequency ablation (RFA) has evolved into an important therapeutical tool for the treatment of non resectable primary and secondary liver tumors. The clinical benefit of RFA is represented in several clinical studies. They underline the safety and feasibility of this new and modern concept in treating liver tumors. RFA has proven its clinical impact not only in hepatocellular carcinoma (HCC) but also in metastatic disease such as colorectal cancer (CRC). Due to the increasing number of HCC and CRC, RFA might play an even more important role in the future. Therefore, the refinement of RFA technology is as important as the evaluation of data of prospective randomized trials that will help define guidelines for good clinical practice in RFA application in the future. The combination of hepatic resection and RFA extends the feasibility of open surgical procedures in patients with extensive tumors. Adverse effects of RFA such as biliary tract damage, liver failure and local recurrence remain an important task today but overall the long term results of RFA application in treating liver tumors are promising. Incomplete ablation of liver tumors due to insufficient technology of ablation needles, tissue cooling by the neighbouring blood vessels, large tumor masses and ablation of tumors in close vicinity to heat sensitive organs remain difficult tasks for RFA. Future solutions to overcome these limitations of RFA will include refinement of ultrasonographic guidance (accuracy of probe placement), improvements in needle technology (e.g. needles preventing charring) and intraductal cooling techniques.