Kazuki Ikeda

Antibody to hepatitis B core antigen and risk for hepatitis C-related hepatocellular carcinoma : A prospective study

Context Retrospective studies suggest that exposure to hepatitis B virus (HBV) may contribute to the development of hepatocellular carcinoma (HCC) in hepatitis C virus (HCV)positive patients with cirrhosis. Contribution These investigators prospectively studied patients with chronic HCV infection and evidence of occult HBV infection (negative results for hepatitis B surface antigen and HBV DNA but positive results for antibody to hepatitis B core antigen [anti-HBc] on serologic testing). Patients with HCV-related cirrhosis and positive results for anti-HBc on serologic testing were at high risk for HCC. Anti-HBc positivity was associated with increased risk for HCC, even in patients with a virologic response to interferon therapy. Caution The effect of alcohol cannot be fully assessed because of the small number of study patients who drank moderately. Implication Anti-HBc serologic testing may be a valuable indicator of special risk for HCC in patients with HCV-related cirrhosis. The Editors Hepatocellular carcinoma (HCC) is one of the most common types of cancer worldwide, and its incidence has been increasing (1, 2). In Japan, an endemic area for hepatitis B virus (HBV) and hepatitis C virus (HCV), it is well known that more than 75% of cases of HCC are attributable to HCV-related chronic liver disease, and nearly 15% are attributable to HBV-related liver disease (3). Several reports have focused on the clinical role of HBV as a unique infection, in which HBV DNA is detectable in the liver despite the absence of serum hepatitis B surface antigen (HBsAg) (46). It is increasingly recognized that after a person is exposed to HBV, infection persists in the liver for a prolonged period (710). This unique persistent infection, known as occult (or latent) HBV infection, is characterized by HBV DNA in the liver but no HBsAg in the serum (1113). In most cases, antibody to hepatitis B core antigen (anti-HBc) is detectable, and thus anti-HBc is believed to be a surrogate marker for latent carriers (14). In fact, we recently showed that HBV infection invariably occurred through grafts from anti-HBcpositive donors in HBV-naive recipients through living-donor liver transplantation (15). In addition to our data, other reports showing frequent HBV transmission from anti-HBcpositive cadaveric donors to recipients indicate that most healthy persons who are positive for anti-HBc, even at low titers, have latent HBV infection in liver tissue (11, 1618). Indeed, we have shown that most anti-HBcpositive healthy persons have a latent episomal form of HBV infection accompanied by ongoing viral replication (19, 20). In contrast, the prevalence of latent HBV infection in anti-HBcpositive patients with HCV-related chronic liver disease, including chronic hepatitis, cirrhosis, and HCC, remains controversial (21). However, several reports have revealed that the HBV genome is frequently detectable in liver tumors in anti-HBcpositive, HBsAg-negative patients with HCV-related liver disease, which suggests that occult HBV infection may contribute to the progression of liver damage and the development of HCC in HCV-positive patients (14, 2227). In a large-scale retrospective study of the prevalence of anti-HBc among 2014 patients with chronic HCV infection, we found that nearly 50% of patients with HCV-related liver disease had anti-HBc (28). Moreover, we found a strong correlation between the prevalence of anti-HBc and the clinical progression of liver disease. The prevalence of anti-HBc was approximately 60% in patients with HCV-related HCC (28). This high prevalence of anti-HBc in HCV-positive patients, particularly those with HCC, strongly suggests that previous exposure to HBV plays an important role in the development of HCC in patients with HCV-related chronic liver disease. Therefore, we performed a prospective study to determine whether previous exposure to HBV affects the clinical course, especially in development of HCC, in patients with chronic HCV infection. Methods Patients Patients with chronic HCV infection who presented to Kyoto University, Kyoto, Japan, and 14 affiliated core hospitals from May 1995 to June 1995 were enrolled. To be eligible, patients had to have serologically confirmed HCV infection without HBsAg and HBV DNA in sera. All patients had been followed with biochemical tests, including -fetoprotein, and ultrasonography or computed tomography (CT) every 3 to 6 months before and after enrollment. We excluded patients who had elevated -fetoprotein levels or those in whom HCC had been diagnosed before enrollment. As a result, 872 patients with chronic HCV infection were enrolled. We discontinued follow-up in patients who moved from the study districts but included their clinical data until they moved. The end of follow-up was defined as the date of diagnosis of HCC, date of death, date of move from the study district, or the closing date of the study (15 May 2005). A total of 384 patients were classified into the hepatitis group or cirrhosis group on the basis of histologic findings on liver biopsy. The differential diagnosis of cirrhosis or hepatitis was made in the remaining 488 patients by using the cirrhosis discriminant score (29, 30). This score is based on 3 laboratory variables: platelet count, alanine aminotransferaseaspartate aminotransferase ratio, and prothrombin time. It has been shown to be highly sensitive in identifying cirrhosis in patients with HCV infection. In accordance with the original definition, patients with a high score (8) were classified into the cirrhosis group. Patients with ascites confirmed by ultrasonography or CT or previous variceal bleeding were given a diagnosis of cirrhosis, regardless of their score, because these findings are strong indicators of portal hypertension and most likely cirrhosis. As a result, 597 (68.5%) patients had a diagnosis of chronic hepatitis and 275 (31.5%) patients had a diagnosis of cirrhosis at the time of enrollment. The patients had regular clinical assessments, biochemical tests, and ultrasonography or CT of the liver every 3 to 6 months during the follow-up period. Patients were stratified into 3 categories according to their smoking habits: nonsmokers, light smokers who smoked fewer than 20 pack-years, and heavy smokers who smoked 20 pack-years or more. Similarly, we stratified patients into 3 categories according to their drinking habits: nondrinkers, moderate drinkers with an average ethanol intake less than 30 g/d, and heavy drinkers with an average ethanol intake greater than 30 g/d. Information on average alcohol intake was based on the patients drinking habits during the 15 years before study entry. All patients provided informed consent to participate in the study, and the study was designed in accordance with the Declaration of Helsinki (31). Serologic Studies At study entry, serum samples from each patient were tested for serologic markers of HCV. Detection of HBsAg, anti-HBc, and antibody to hepatitis B surface antigen (anti-HBs) was performed by using commercial enzyme immunoassay kits (Dainabot, Tokyo, Japan) (28). Results of the anti-HBc assays were expressed as the percentage of inhibition, and the specimen was considered to be anti-HBc positive when the percentage of inhibition was greater than 50% (19). Detection of HBV DNA was done by using DNA probe assay (32). Anti-HCV was assessed by using second-generation assays (Dainabot) (28). Serum HCV RNA levels were determined in 254 patients by using a competitive reverse transcriptionpolymerase chain reaction assay, and positivity of HCV RNA was confirmed in all patients who were examined at study entry (33). History of Interferon Therapy Of the 576 patients with chronic hepatitis, 224 had a history of interferon therapy. One hundred ninety-two patients received 5 to 10 million U of interferon- intramuscularly every day for the first 2 weeks and then 3 times weekly for the following 22 weeks. The remaining 32 patients were treated with 3 to 6 million U of interferon- intravenously every day for 8 weeks. No patient received pegylated interferon or combination therapy with ribavirin. Patients who received interferon were divided into 3 groups based on their virologic response to therapy. Patients with a sustained virologic response were defined as those with no detectable HCV RNA by qualitative assay at least 24 weeks after cessation of therapy. Patients with relapse were defined as those with disappearance of viremia at the end of treatment followed by reappearance of viremia with 24 weeks. Nonresponders included patients whose serum HCV RNA remained positive during therapy. Statistical Analysis The incidence rates for HCC are expressed as the number of HCC cases per 1000 person-years. Incidence rate ratios were calculated by dividing rates, and the exact 95% CIs for the rate ratios were calculated on the basis of a binomial distribution, which is a conditional distribution for 2 independent Poisson distributions. The Cox proportional hazards model was used to calculate the incidence rate ratios for the association between HBc seropositivity and HCC incidence. The multivariate model, with adjustment for potential risk factors, included male sex, age, alcohol intake (none, 0 to 30 g/d, and 30 g/d), smoking (none, 0 to 20 pack-years, and 20 pack-years), and history of interferon therapy (yes or no). The associated 95% Wald CIs were calculated. Analyses were done by using PC-SAS, version 8.2 (SAS Institute, Inc., Cary, North Carolina) and JMP, version 4.0 (SAS Institute, Inc.). Role of the Funding Source The Japan Society for the Promotion of Science provided funding for the study. The funding source had no role in the collection, analysis, or interpretation of the data or in the decision to submit the paper for publication. Results Characteristics of Patients at Enrollment We followed 846 of the 872 enrolled patients. The remaining 26 patients were excluded from the analysis. Twenty-on

Estimation of Characteristics of Echo Envelope Using RF Echo Signal from the Liver

To realize quantitative diagnosis of liver cirrhosis, we have been analyzing the probability density function (PDF) of echo amplitude using B-mode images. However, the B-mode image is affected by the various signal and image processing techniques used in the diagnosis equipment, so a detailed and quantitative analysis is very difficult. In this paper, we analyze the PDF of echo amplitude using RF echo signal and B-mode images of normal and cirrhotic livers, and compare both results to examine the validity of the RF echo signal.

Identification of novel defective HCV clones in liver transplant recipients with recurrent HCV infection

Summary.  Patients with recurrent hepatitis C after liver transplantation usually have a high viral load and are generally resistant to interferon (IFN)‐α2b plus ribavirin (RBV) therapy. However, it remains unclear whether pretreatment viral titre determines the effectiveness of combination therapy, especially in patients with a high viral load. The aim of this study was to identify the viral factors associated with a sustained virological response (SVR) to antiviral therapy in patients with recurrent hepatitis C after living‐donor liver transplantation. Twenty‐three patients with recurrent hepatitis C received combination therapy of IFN‐α2b plus RBV. SVR was achieved in 7 of the 23 patients (30.4%). Predictive factors for SVR included a 2 log10 decline in Hepatitis C virus (HCV) RNA at 2 weeks after the start of therapy and disappearance of HCV RNA at 4 or 24 weeks after the start of therapy. As the pretreatment high viral load showed no association with SVR, we asked whether other viral factor was associated with the response to the combination therapy in transplant recipients. We found the several novel defective HCV clones in 4 of 12 recipients’ sera. All defective HCV clones had deletions in the envelope region. Interestingly, no patients with defective clones showed a prompt decrease in HCV RNA after the start of IFN‐α2b plus RBV therapy. Thus, early decline in serum HCV RNA after treatment was closely associated with SVR. The circulating defective HCV clones are present and might be associated with the response to the combination therapy in patients with recurrent hepatitis after liver transplantation.

Translational research on HGF: A phase I/II study of recombinant human HGF for the treatment of fulminant hepatic failure

Hepatocyte growth factor (HGF) is a potential therapeutic agent for fatal liver diseases, including fulminant hepatic failure (FHF). After performing a number of preclinical tests with recombinant human HGF (rh‐HGF), we started a phase I/II study in September 2005 of patients with FHF or late‐onset hepatic failure (LOHF), to examine the safety and clinical efficacy of rh‐HGF. We first administered rh‐HGF (0.6 mg/m2/day) for 13 days to a 67‐year‐old Japanese man with FHF. All data from this patient were reviewed by the independent data monitoring committee, and the safety of rh‐HGF was recognized. Finally, a clinical trial of rh‐HGF was approved to be continued. As of August 2007, we have administered rh‐HGF to four patients with FHF or LOHF. All patients showed a moderate decrease in systolic blood pressure during rh‐HGF administration, while the urinary excretion of albumin did not increase in all cases. In the first and third patients, hepatic failure gradually progressed, and they died 66 and 29 days, respectively, after encephalopathy occurred. The second and fourth patients are presently still alive. In conclusion, we started a clinical trial that examined the effects of rh‐HGF in patients with FHF or LOHF, and in the four patients with FHF or LOHF enrolled in this study, repeated doses of rh‐HGF did not produce any severe side effects.

Endoscopically resected long giant polypoidal lesion caused by arteriovenous malformation

A 70-year-old man was referred to our hospital because of a positive fecal occult blood test result. Colonoscopy revealed a long giant polypoidal lesion in the sigmoid colon, and the lesion occupied the colonic lumen. The tip side of the lesion showed redness, suggesting congestion (A). On compression with forceps, the lesion was easily dented; thus, we excluded a solid tumor, such as a submucosal tumor. The lesion showed no apparent pulsatile movement. Considering the possibility that invagination might develop, we decided to resect it endoscopically.