Long-term survival following treatment of hepatocellular carcinoma in Singapore: evaluation of Wellferon in the prophylaxis of high-risk pre-cancerous conditions

Incidence of hepatocellular carcinoma in untreated subjects with chronic hepatitis B: a systematic review and meta-analysis

BACKGROUND & AIMS

In the natural history of hepatitis B virus (HBV) chronic infection, the hepatocellular carcinoma (HCC) risk is unclear. We assessed incidence and predictors of HCC by a systematic review and meta-analysis.

METHODS

We included longitudinal studies and randomized controlled trials assessing HCC incidence in untreated patients with HBV chronic infection. Incidence rates and their 95% confidence intervals were extracted by each study and pooled together in random effects models.

RESULTS

Sixty-six studies were included with a total of 347 859 patients. According to liver disease status, the summary incidence rates were in Europe, North America and East Asia, respectively: (a) asymptomatic carriers: 0.07 (95% confidence interval: 0.05-0.09), 0.19 (0.07-0.31) and 0.42 (0.21-0.63) per 100 person-years, respectively; (b) inactive carriers: 0.03 (0.0-0.10), 0.17 (0.02-0.62) and 0.06 (0.02-0.10), respectively; (c) chronic hepatitis: 0.12 (0.0-0.27), 0.48 (0.22-0.91) and 0.49 (0.32-0.66), respectively; (d) compensated cirrhosis (Child-Pugh A): 2.03 (1.30-2.77), 2.89 (1.23-4.55) and 3.37 (2.48-4.26) respectively. Multivariate meta-regression showed a significant increase in incidence rates for age, and for status of a symptomatic carrier, chronic hepatitis and compensated cirrhosis compared to inactive carrier, but not for geographical area after adjusting for age. An increase in the incidence rates was also observed for alcohol intake ≥60 g/dl, HBV genotype C with respect to B and HBV-DNA serum levels >2000 IU/ml, in Asian studies.

CONCLUSIONS

Hepatocellular carcinoma risk in untreated subjects with HBV chronic infection is strongly related with age and liver disease status.

Hepatocellular Carcinoma Screening and Surveillance: Practice Guidelines and Real-Life Practice

Hepatocellular carcinoma (HCC) is the seventh most common malignancy worldwide. HCC meets all the criteria established by the World Health Organization for performing surveillance on those at-risk for developing cancer. Although there are consensus guidelines in the United States, Europe, and Asia for HCC surveillance, it is unclear if these guidelines are regularly implemented in routine practice to optimize real-life clinical outcomes. We reviewed the current literature on the adherence to current HCC practice guidelines by the American Association for the Study of Liver Diseases (2009), the European Association for the Study of the Liver (2012), and the Asia Pacific Association for the Study of the Liver (2010) for screening/surveillance and outcomes of optimal versus poor adherence. We performed PubMed search for relevant articles regarding HCC surveillance and screening worldwide. Currently, HCC screening is underutilized to a large extent. In most studies, the adherence to HCC screening and surveillance is suboptimal. Various patient, provider, and health care system factors may have all contributed to such nonadherence. Strategies to improve HCC screening and surveillance are urgently needed for early HCC detection and improved survival of HCC patients. Further research is needed to elucidate the various medical and/or cultural knowledge, belief, and practice patterns that can lead to barriers to HCC screening and surveillance at both patient and provider levels. These data will help focus and target advocacy and educational efforts to improve HCC surveillance at all levels: patients, providers, and health care system/government.

Management of hepatitis B virus infection during treatment for hepatitis B virus-related hepatocellular carcinoma

Although liver resection is considered the most effective treatment for hepatocellular carcinoma (HCC), treatment outcomes are unsatisfactory because of the high rate of HCC recurrence. Since we reported hepatitis B e-antigen positivity and high serum hepatitis B virus (HBV) DNA concentrations are strong risk factors for HCC recurrence after curative resection of HBV-related HCC in the early 2000s, many investigators have demonstrated the effects of viral status on HCC recurrence and post-treatment outcomes. These findings suggest controlling viral status is important to prevent HCC recurrence and improve survival after curative treatment for HBV-related HCC. Antiviral therapy after curative treatment aims to improve prognosis by preventing HCC recurrence and maintaining liver function. Therapy with interferon and nucleos(t)ide analogs may be useful for preventing HCC recurrence and improving overall survival in patients who have undergone curative resection for HBV-related HCC. In addition, reactivation of viral replication can occur after liver resection for HBV-related HCC. Antiviral therapy can be recommended for patients to prevent HBV reactivation. Nevertheless, further studies are required to establish treatment guidelines for patients with HBV-related HCC.

Causes of and prevention strategies for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a challenging malignancy of global importance. It is associated with a high rate of mortality and its prevalence in the United States and in Western Europe is increasing. Cirrhosis is the strongest and the most common known risk factor for HCC, usually due to hepatitis C virus (HCV) and hepatitis B virus (HBV) infections. However, different lines of evidence identify in non-alcoholic fatty liver disease (NAFLD) a possible relevant risk factor for occurrence of HCC. Given the continuing increase in the prevalence of obesity and diabetes, the incidence of non-alcoholic steatohepatitis-related HCC may also be expected to increase, and a potential role of behavior treatment and/or insulin-sensitizing drugs can be envisaged. Vaccination against HBV is the most efficient primary prevention measure currently available to reduce the HCC incidence and mortality in high-incidence areas, while data on the role of interferon (IFN) and nucleos(t)ide analogues (NUC) are still controversial. The pooling of data from the literature suggests a slight preventive effect of antiviral therapy on HCC development in patients with HCV-related cirrhosis, but the preventive effect is limited to sustained virological responders.

Prediction of liver-related events using fibroscan in chronic hepatitis B patients showing advanced liver fibrosis

BACKGROUND

Liver stiffness measurement (LSM) using transient elastography (FibroScan®) can assess liver fibrosis noninvasively. This study investigated whether LSM can predict the development of liver-related events (LREs) in chronic hepatitis B (CHB) patients showing histologically advanced liver fibrosis.

METHODS

Between March 2006 and April 2010, 128 CHB patients with who underwent LSM and liver biopsy (LB) before starting nucleot(s)ide analogues and showed histologically advanced fibrosis (≥F3) with a high viral loads [HBV DNA ≥2,000 IU/mL] were enrolled. All patients were followed regularly to detect LRE development, including hepatic decompensation (variceal bleeding, ascites, hepatic encephalopathy, spontaneous bacterial peritonitis, hepatorenal syndrome) and hepatocellular carcinoma (HCC).

RESULTS

The mean age of the patient (72 men, 56 women) was 52.2 years. During the median follow-up period [median 27.8 (12.6-61.6) months], LREs developed in 19 (14.8%) patients (five with hepatic decompensation, 13 with HCC, one with both). Together with age, multivariate analysis identified LSM as an independent predictor of LRE development [P<0.044; hazard ratio (HR), 1.038; 95% confidence interval (CI), 1.002-1.081]. When the study population was stratified into two groups using the optimal cutoff value (19 kPa), which maximized the sum of sensitivity (61.1%) and specificity (86.2%) from a time-dependent receiver operating characteristic curve, patients with LSM>19 kPa were at significantly greater risk than those with LSM≤19 kPa for LRE development (HR, 7.176; 95% CI, 2.257-22.812; P = 0.001).

CONCLUSION

LSM can be a useful predictor of LRE development in CHB patients showing histologically advanced liver fibrosis.

Anticarcinogenic impact of interferon therapy on the progression of hepatocellular carcinoma in patients with chronic viral infection

Hepatocellular carcinoma (HCC) is mainly caused by a persistent infection due to the hepatitis B or hepatitis C virus. The number of HCC cases is increasing in Asian and African countries, as well as in European and American countries. Interferon (IFN) therapy, used for type B chronic liver diseases, inhibits hepatic carcinogenesis in patients with compensated cirrhosis. However, there is insufficient evidence that IFN therapy inhibits hepatic carcinogenesis in patients with chronic hepatitis B. There are few cases of HCC due to chronic hepatitis B, and long-term follow-up periods verifying the inhibitory effect of IFN on hepatic carcinogenesis have not been obtained. To improve the prognosis of type B chronic liver diseases, it is important that hepatitis treatment follows guidelines in which a patient's age and the extent of hepatic fibrosis are taken into account. As for chronic hepatitis C, since a sustained virological response (SVR) in IFN therapy inhibits hepatic carcinogenesis and improves prognosis, treatment that aims for an SVR while taking into consideration host-sided and virus-sided factors is recommended for patients with type C chronic liver diseases. In areas with low incidence of HCC (e.g. USA), a large number of cases and a long-term follow-up period are needed before it can be accepted that IFN therapy inhibits hepatic carcinogenesis. After locally curative treatment of HCC, IFN therapy suppresses recurrence and improves survival rates.

Epidemiology of primary and secondary liver cancers

Primary liver cancer is the sixth most common cancer worldwide with a wide geographic distribution. The incidence of primary liver cancer is increasing and there is still a higher prevalence in developing countries. Early recognition remains an obstacle and lack of it results in poor outcomes for hepatocellular carcinoma (HCC), the most prevalent primary liver cancer, and cholangiocarcinoma. The most common risk factors associated with HCC are hepatitis B and chronic hepatitis C infections, alcohol use, smoking, and aflatoxin exposure. Emerging risk factors such as obesity might play an important role in the future because of the increasing prevalence of this condition.

Long-term effect of interferon treatment on the progression of chronic hepatitis B: Bayesian meta-analysis and meta-regression

AIM

  The long-term effects of interferon treatment on the progression of chronic hepatitis B (CHB) have been studied extensively, but its true clinical benefits and the predictors of its efficacy remain unclear.

METHODS

  A systematic published work search was undertaken. Eligible studies included those with interferon treatment and control groups, and with liver cirrhosis (LC), hepatocellular carcinoma (HCC) or death as main outcomes. Bayesian meta-analysis and meta-regression were performed to assess associations between interferon treatment and disease progression, and the impacts of potential covariates.

RESULTS

  Eleven articles met the inclusion criteria. LC, HCC and death were end-points in four, nine and six studies, respectively. In all studies, interferon was associated with significant preventive effects on HCC according to the DerSimonian-Laird method (relative risk [RR] = 0.470, 95% confidence interval [CI] = 0.260-0.850) and Bayesian method adjusting underlying risk (RR = 0.249, 95% Bayesian credible intervals [BCI] = 0.049-0.961), but not according to Bayesian meta-analysis (RR = 0.274, 95% BCI = 0.059-1.031); and it showed similar effects in death but not in LC. However, most of the high-quality studies never revealed protective benefits in these end-points. Bayesian meta-regression identified Asian ethnicity in death, higher hepatitis B e-antigen (HBeAg) seroconversion rate or positivity rate, and length of follow up (≤5 years) in HCC as potentially protective against disease progression. Subgroup analysis confirmed similar effects from these factors in HCC and death.

CONCLUSION

  Additional evidence is needed to support the role of interferon in delaying CHB progression.

Does chemotherapy prevent HBV-related hepatocellular carcinoma? Cons

The retrospective scrutiny of studies that were originally designed to assess the antiviral activity of interferon (IFN) and nucleos(t)ide analogues (NUC) suggested reduced incidence of hepatocellular carcinoma (HCC) in responders. The interpretation of these studies, however, is questioned by the heterogeneity of patient referral, adoption of surrogate end-points, lack of control arms and, overall, by the lack of power to capture enough hard end-points of the natural history of hepatitis B, including HCC. Another point of criticism is that above all, IFN studies could have been affected by study enrolment skewed towards patients with less advanced liver disease, who had a better predicted compliance to therapy but a lower risk of developing HCC in the short-term. In my opinion, these constraints coupled with the lack of patient stratification by HCC predictors, make the evaluation of the prophylactic activity of IFN and NUC even more difficult. Overall, while single studies provide some evidence for a reduced HCC incidence in virological responders, particularly in those with moderate liver fibrosis, we still lack confirmation that anti-HBV therapy prevents HCC in patients with an established cirrhosis, too. Finally, tertiary prevention with anti-HBV treatments is controversial, due to the existence of a few, methodologically flawed studies.

Combination therapy with transarterial chemoembolization and interferon-alpha compared with transarterial chemoembolization alone for hepatitis B virus related unresectable hepatocellular carcinoma

BACKGROUND AND AIMS

The present study was carried out to test the hypothesis that interferon-alpha (IFN-alpha) treatment would reduce or postpone the recurrence rate and improve the overall survival rate in patients after transarterial chemoembolization (TACE) treatment of hepatitis B virus (HBV) related unresectable hepatocellular carcinoma (HCC).

METHODS

216 patients with unresectable HBV-related HCC were randomized into a TACE group and a TACE-IFN group, each group had 108 patients. In the TACE-IFN group, patients received IFN-alpha1b at a dose of 3 million units (mu) three times a week by intramuscular injection one week after/before TACE treatment, for 48 weeks.

RESULTS

The median disease-free survival in the TACE-IFN treatment group was 23.6 months (95% CI: 21.4-25.8) and 20.3 months (95% CI: 15.8-24.8) in the TACE group (P = 0.027). The disease free rate at 24 months in the TACE group was lower than in the TACE-IFN group (39.8% vs 59.3%, P = 0.004). The median overall survival was 29 months (95% CI: 27.5-32.1) in the TACE-IFN group and 26 months (95% CI: 20.1-31.9) in the TACE group (P = 0.003). The 2-year overall survival in the TACE-IFN group was higher than in the TACE group (72.2% vs 52.8%, P = 0.003).

CONCLUSIONS

IFN-alpha treatment reduced recurrence and improved the survival of patients after TACE treatment of HBV-related HCC, with acceptable toxicities.

Natural history of chronic hepatitis B: special emphasis on disease progression and prognostic factors

The natural history of chronic hepatitis B virus (HBV) infection and disease is complex and highly variable. We review the natural history of chronic hepatitis B with emphasis on the rates of disease progression and factors influencing the course of the liver disease. Chronic hepatitis B is characterized by an early replicative phase (HBeAg positive chronic hepatitis) and a late low or non-replication phase with HBeAg seroconversion and liver disease remission (inactive carrier state). Most patients become inactive carriers after spontaneous HBeAg seroconversion with good prognosis, but progression to HBeAg negative chronic hepatitis due to HBV variants not expressing HBeAg occurs at a rate of 1-3 per 100 person years following HBeAg seroconversion. The incidence of cirrhosis appears to be about 2-fold higher in HBeAg negative compared to HBeAg positive chronic hepatitis. In the cirrhotic patient the 5-year cumulative risk of developing hepatocellular carcinoma is 17% in East Asia and 10% in the Western Europe and the United States and the 5-year liver related death rate is 15% in Europe and 14% in East Asia. There is a growing understanding of viral, host and environmental factors influencing disease progression, which ultimately could improve the management of chronic hepatitis B.

A randomized, controlled trial of postoperative adjuvant interferon therapy after resection of hepatocellular carcinoma

OBJECTIVE

We conducted a randomized controlled trial of adjuvant interferon therapy in patients with predominantly hepatitis B-related hepatocellular carcinoma (HCC) to investigate whether the prognosis after hepatic resection could be improved.

SUMMARY BACKGROUND DATA

Recurrence is common after hepatic resection for HCC. Interferon possesses antiviral, immunomodulatory, antiproliferative, and antiangiogenic effects and may be an effective form of adjuvant therapy.

PATIENTS AND METHODS

Since February 1999, patients with no residual disease after hepatic resection for HCC were randomly assigned with stratification by pTNM stage to receive no treatment (control group), interferon alpha-2b 10 MIU/m (IFN-I group) or 30 MIU/m (IFN-II group) thrice weekly for 16 weeks. Enrollment to the IFN-II group was terminated from January 2000 because adverse effects resulted in treatment discontinuation in the first 6 patients. By June 2002, 40 patients each had been enrolled into the control group and IFN-I group. The baseline clinical, laboratory, and tumor characteristics of both groups were comparable.

RESULTS

The 1- and 5-year survival rates were 85% and 61%, respectively, for the control group and 97% and 79%, respectively, for the IFN-I group (P = 0.137). After adjusting for the confounding prognostic factors in a Cox model, the relative risk of death for interferon treatment was 0.42 (95% CI, 0.17-1.05; P = 0.063). Exploratory subset analysis showed that adjuvant interferon had no survival benefit for pTNM stage I/II tumor (5-year survival 90% in both groups; P = 0.917) but prevented early recurrence and improved the 5-year survival of patients with stage III/IVA tumor from 24% to 68% (P = 0.038).

CONCLUSION

In a group of patients with predominantly hepatitis B-related HCC, adjuvant interferon therapy showed a trend for survival benefit, primarily in those with pTNM stage III/IVA tumors. Further larger randomized trials stratified for stage are needed.

Hepatocellular carcinoma prevention: A worldwide emergence between the opulence of developed countries and the economic constraints of developing nations

Hepatocellular carcinoma (HCC) is the fifth most common neoplasm, the major cause of death in patients with liver cirrhosis, and the third most common cause of cancer-related death in the world. The geographic distribution of HCC varies significantly and 80% of cases occur in developing countries (Far East and South Asia) where the prevalence of viral hepatitis is higher. The treatment of HCC is difficult because most patients are diagnosed when the tumour is in an advanced stage and is not amenable to potential curative therapy, thus prevention is the key to reducing HCC and its related morbidity and mortality. HCC is unique among cancers, occurring mostly in patients with a known risk factor. Ninety percent of HCCs develop in the context of chronic liver diseases and mainly in patients with cirrhosis. Viral hepatitis is the most common cause of HCC worldwide, followed by alcoholic liver disease (ALD) and other causes such as non-alcoholic fatty liver disease (NAFLD), genetic haemocromatosis (GH) and primary biliary cirrhosis in an advanced stage (III-V). In certain areas of the People’s Republic of China, exposure to aflatoxin and HBV infection are thought to be responsible for the extraordinary high risk of HCC. Substantial progresses in the prevention of virusl-related hepatitis (screening of blood units, use of disposable sanitary tools, HBV vaccination) have been achieved in developed countries, but in the same areas, alcohol- and dysmetabolism-related HCCs are emerging problems which require specific interventions in terms of public health measures. In developing countries, economic constraints limit the development of any program for the prevention of viral hepatitis transmission (including health education campaigns, healthcare politics, primary prevention and the improvement of hygienic and sanitary conditions). When viral liver disease is established, only a minority of patients are treated worldwide and benefit a possible preventive effect of medical treatment on HCC development. Thus the real contribution of medical treatment to HCC prevention in patients with chronic viral hepatitis is small. Great efforts are needed to identify more effective medical measures for primary and secondary prevention of HCC.

Prevention of hepatocellular carcinoma recurrence with alpha-interferon after liver resection in HCV cirrhosis

Tumor recurrence after resection of hepatocellular carcinoma (HCC) can occur early (<2 years) or late (>2 years) as metastases or de novo tumors. Interferon (IFN) has the potential for chemoprevention against hepatitis C virus (HCV)-related cirrhosis. A predetermined group of 150 HCV RNA-positive patients undergoing resection of early- to intermediate-stage HCC was stratified into 80 HCV-pure (hepatitis B anticore antibody [anti-HBc]-negative) and 70 mixed HCV+hepatitis B virus (HBV) (anti-HBc-positive) groups, then randomized to IFN-alpha (3 million units 3 times every week for 48 weeks [n = 76]) versus control (n = 74). The primary end point was recurrence-free survival (RFS); secondary end points were disease-specific and overall survival. Intention-to-treat and subgroup analysis on adherent patients were conducted. Treatment effects on early/late recurrences were assessed using multiple Cox regression analysis. No patient experienced life-threatening adverse events. There were 28 adherent patients (37%). After 45 months of median follow-up, overall survival was 58.5%, and no significant difference in RFS was detectable between the two study arms (24.3% vs. 5.8%; P = .49). HCC recurred in 100 patients (48 IFN-treated, 52 controls), with a 50% reduction in late recurrence rate in the treatment arm. HCC multiplicity and vascular invasion were significantly related to recurrence (P = .01 and .0003). After viral status stratification, while no treatment effect was apparent in the mixed HCV+HBV population and on early recurrences (72 events), there was a significant benefit on late recurrences (28 events) in HCV-pure patients adherent to treatment (HR: 0.3; 95% CI: 0.09-0.9; P = .04). In conclusion, IFN does not affect overall prevention of HCC recurrence after resection, but it may reduce late recurrence in HCV-pure patients receiving effective treatment.

P48 is a predictive marker for outcome of postoperative interferon-alpha treatment in patients with hepatitis B virus infection-related hepatocellular carcinoma

BACKGROUND

Postoperative interferon-alpha (IFN-alpha) therapy improved survival in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). The identification of predictive markers of outcome will help to select patients who are most likely to benefit from treatment.

METHODS

An immunohistochemical study of P48 was performed on specimens that were collected from patients in a randomized trial who received postoperative IFN-alpha therapy (Group 1; n = 80 patients) and who did not receive postoperative IFN-alpha therapy (Group 2; n = 75 patients). Positive P48 expression was graded as >/=20% positive cells in 1 sample.

RESULTS

Eighty-one patients were positive for P48, and 74 patients were negative for P48. The clinicopathologic data were comparable between patients with P48-negative and P48-positive staining. Disease-free survival (DFS) and overall survival (OS) in P48-positive patients were better than that in P48-negative patients in Group 1 (DFS, P = .036; OS, P = .014), however, DFS and OS did not differ between patients with positive and negative P48 in Group 2. OS in P48-positive patients from Group 1 was better than that in patients with P48-positive patients from Group 2 (OS, P = .001) but did not differ when P48 was negative. In Group 1, the risk factors for DFS were cirrhosis and P48 staining, and the risk factors for OS were tumor differentiation and P48 staining. Receiver operating curve analysis indicated that, in the first 2 years of DFS, combined cirrhosis and P48 had good predictive accuracy; and, in the first 4 years of OS, combined tumor differentiation and P48 had good predictive accuracy.

CONCLUSIONS

P48 was useful as a predictive marker of outcome after postoperative IFN-alpha treatment in patients with HBV-related HCC.

Infectious Agents

There is substantial evidence that infectious agents play a causal role in a variety of human malignancies. These cancers include the liver, cervix, stomach, nasopharynx, bladder, and bile duct as well as Kaposi sarcoma (KS) and several lymphomas. This chapter summarizes the biological and epidemiologic features of each of the major oncogenic infections, beginning with the viruses, followed by H. pylori, and with a brief summary of the relevant parasites.

Hepatitis B virus-related hepatocellular carcinogenesis and its prevention

To elucidate the influence of serum hepatitis B virus (HBV) load on hepatocellular carcinogenesis in cirrhotic patients, HBV-DNA was sequentially measured. In a nested, case-control study using 96 patients without antiviral therapy, high HBV-DNA (> or =10(3.7) copies/ml) in the last 3 years was significantly associated with carcinogenesis (a patient group without hepatocellular carcinoma (HCC) development; 0/48 vs. a patient group with eventual HCC development; 22/48, p < 0.0001). No patient with a continuously low HBV-DNA for the last 3 years developed HCC. Persistence of high HBV-DNA concentration suggested an increased risk of carcinogenesis. In a retrospective cohort study using 57 patients with interferon therapy, HCC developed in 2 (8.0%) of the 25 patients with HBV-DNA loss, while carcinogenesis was found in 11 (34.4%) of 32 patients without HBV-DNA loss (Fisher's exact test, p = 0.026). A significant decrease or loss of serum HBV-DNA stops HCC development, and its sequential analysis could be very useful both in the prediction and early detection of small HCC.

Viral hepatitis and hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world. The incidence of HCC varies considerably with the geographic area because of differences in the major causative factors. Chronic hepatitis B and C, mostly in the cirrhotic stage, are responsible for the great majority of cases of HCC worldwide. The geographic areas at the highest risk are South-East Asia and sub-Saharan Africa, here hepatitis B is highly endemic and is the main cause of HCC. In areas with an intermediate rate of HCC such as Southern Europe and Japan, hepatitis C is the predominant cause, whereas in low rate areas such as Northern Europe and the USA, HCC is often related to other factors as alcoholic liver disease. There is a rising incidence in HCC in developed countries during the last two decades, due to the increasing rate of hepatitis C infection and improvement of the clinical management of cirrhosis.

METHODS

This article reviews the literature on hepatitis and hepatocellular carcinoma. The Medline search was carried out using these key words and articles were selected on epidemiology, risk factors, screening, and prevention of hepatocellular carcinoma.

RESULTS

Screening of patients with advanced chronic hepatitis B and C with hepatic ultrasound and determination of serum alfa-fetoprotein may improve the detection of HCC, but further studies are needed whether screening improves clinical outcome. Hepatitis B and C viruses (HBV/HCV) can be implicated in the development of HCC in an indirect way, through induction of chronic inflammation, or directly by means of viral proteins or, in the case of HBV, by creation of mutations by integration into the genome of the hepatocyte.

CONCLUSION

The most effective tool to prevent HCC is avoidance of the risk factors such as viral infection. For HBV, a very effective vaccine is available. Preliminary data from Taiwan indicate a protective effect of universal vaccination on the development of HCC. Vaccination against HBV should therefore be a health priority. In patients with chronic hepatitis B or C, interferon-alfa treatment in a noncirrhotic stage is protective for HCC development in responders, probably by prevention of cirrhosis development. When cirrhosis is already present, the protective effect is less clear. For cirrhosis due to hepatitis B, a protective effect was demonstrated in Oriental, but not in European patients. For cirrhosis due to hepatitis C, interferon-alfa treatment showed to be protective in some studies, especially in Japan with a high incidence of HCC in untreated patients. Virological, but also merely biochemical response, seems to be associated with a lower risk of development of HCC. As most studies are not randomized controlled trials, no definitive conclusions on the long-term effects of interferon-alfa in HBV or HCV cirrhosis can be established. Especially in hepatitis C, prospective studies should be performed using the more potent reference treatments for cirrhotics, namely the combination of peginterferon and ribavirin.

Prevention of hepatocellular carcinoma

The accuracy and the reliability of well-recognized clinical, virologic, histologic, and molecular risk factors for hepatocellular carcinoma are still insufficient; thus, accurate risk prediction of developing cancer in individual patients remains an elusive goal.

Significance of hepatitis B virus DNA clearance and early prediction of hepatocellular carcinogenesis in patients with cirrhosis undergoing interferon therapy: long-term follow up of a pilot study

BACKGROUND AND AIM

Because the anti-carcinogenic effect and mechanism of interferon (IFN) in patients with hepatitis B virus (HBV)-related cirrhosis have not been elucidated, quantitative analysis of HBV-DNA concentration was carried out sequentially.

METHOD

Of 60 consecutive patients with cirrhosis who began IFN therapy between 1986 and 1990, 57 patients were completely observed for the appearance of hepatocellular carcinoma (HCC). All patients underwent intermittent administration of IFN for a median period of 18 months. HBV-DNA was quantified using transcription mediated amplification and hybridization protection assay. A HBV-DNA count <3.7 log-genome equivalent (LGE)/mL (equivalent to 10(3.7) or 5000 copies/mL) was considered to be a negative value.

RESULTS

Of 25 patients who had HBV-DNA loss after IFN therapy, nine lost HBV-DNA during the therapy and 16 lost HBV-DNA after cessation of the therapy. The other nine patients showed a transient loss of HBV-DNA, and the remaining 23 retained persistently positive HBV-DNA during and after therapy. Although HCC developed in two (8.0%) of the 25 patients with HBV-DNA loss, carcinogenesis was found in 11 (34.4%) of 32 patients without HBV-DNA loss (Fisher's exact test, P = 0.026). In the two exceptional patients, HCC was detected at 1.2 and 3.6 years after loss of HBV-DNA, respectively. When the HBV-DNA concentration decreased by 2 LGE/mL (decrease to 1/100) at 6 months after initiation of interferon, HBV-DNA became negative eventually in 15 (60.0%) of 25 patients.

CONCLUSION

A significant decrease or loss of serum HBV-DNA prevents development of HCC, and sequential analysis of HBV-DNA could be very useful in both the prediction and the early detection of small HCC.

Hepatocellular carcinoma in cirrhosis: incidence and risk factors

Emerging data indicate that the mortality rate of hepatocellular carcinoma (HCC) associated with cirrhosis is rising in some developed countries, whereas mortality from non-HCC complications of cirrhosis is decreasing or is stable. Cohort studies indicate that HCC is currently the major cause of liver-related death in patients with compensated cirrhosis. Hepatitis C virus (HCV) infection is associated with the highest HCC incidence in persons with cirrhosis, occurring twice as commonly in Japan than in the West (5-year cumulative incidence, 30% and 17%, respectively), followed by hereditary hemochromatosis (5-year cumulative incidence, 21%). In hepatitis B virus (HBV)-related cirrhosis, the 5-year cumulative HCC risk is 15% in high endemic areas and 10% in the West. In the absence of HCV and HBV infection, the HCC incidence is lower in alcoholic cirrhotics (5-year cumulative risk, 8%) and subjects with advanced biliary cirrhosis (5-year cumulative risk, 4%). There are limited data on HCC risk in cirrhosis of other causes. Older age, male sex, severity of compensated cirrhosis at presentation, and sustained activity of liver disease are important predictors of HCC, independent of etiology of cirrhosis. In viral-related cirrhosis, HBV/HCV and HBV/HDV coinfections increase the HCC risk (2- to 6-fold relative to each infection alone) as does alcohol abuse (2- to 4-fold relative to alcohol abstinence). Sustained reduction of HBV replication lowers the risk of HCC in HBV-related cirrhosis. Further studies are needed to investigate other viral factors (eg, HBV genotype/mutant, occult HBV, HIV coinfection) and preventable or treatable comorbidities (eg, obesity, diabetes) in the HCC risk in cirrhosis.

Antiviral therapy in patients with chronic hepatitis B and cirrhosis

Chronic hepatitis B virus infection (HBV) may result in significant morbidity, including cirrhosis, end-stage liver disease, and hepatocellular carcinoma. The management of chronic HBV cirrhosis is advancing rapidly. Current treatment options for patients with HBV-related cirrhosis include interferon-alpha (IFN-alpha), lamivudine and adefovir dipivoxil. IFN-a is used less commonly today because of its toxicity, difficulty with administration, and the availability of safer drugs. Lamivudine, an oral nucleoside analog, has proven to be at least as effective, and is safer, than IFN-a in the treatment of HBV-related cirrhosis. It is plagued by the development of resistant viral mutants, however. The newest oral nucleotide analog, adefovir dipivoxil, has shown excellent efficacy in treatment-naïve and lamivudine-resistant HBV patients and has lower rates of resistance in the short-term.

Comparison of long-term effects of lymphoblastoid interferon alpha and recombinant interferon alpha-2a therapy in patients with chronic hepatitis B

To compare the long-term effect of natural lymphoblastoid interferon-alpha (IFN-alpha nl) and recombinant IFN-alpha 2a therapy in patients with chronic hepatitis B, 210 patients in two trials were followed-up for 1.1-15.5 years following the end of therapy. They included 34 patients who received placebo (control), 67 treated with IFN-alpha nl (36 after prednisolone priming) and 109 treated with IFN-alpha 2a (56 after prednisolone priming). The cumulative sustained response was higher in patients who had been treated with IFN-alpha nl after prednisolone priming than was exhibited using IFN-alpha nl alone, IFN-alpha 2a alone or the placebo (P < 0.05), or IFN-alpha 2a following prednisolone priming (P = 0.052) at the end of 11 years. Hepatocellular carcinoma (HCC) was detected in 1.5% of the IFN-alpha nl group, 3.7% of the IFN-alpha 2a group and 14.7% of the control group (control vs IFN-alpha nl or IFN-alpha 2a, P < 0.05). The cumulative HCC development was higher in the control group than in the IFN-alpha nl group (P < 0.002) and the IFN-alpha 2a group (P = 0.06). The cumulative survival rate was lower in the control group than in the IFN-alpha nl group (P < 0.01) and the IFN-alpha 2a group (P = 0.02). Multivariate analysis revealed that IFN-alpha nl therapy and female gender are significant predictors of sustained response; preexisting cirrhosis, age at entry and IFN therapy are significant factors in both HCC development and survival. In conclusion, IFN-alpha nl treatment may have a better long-term effect on hepatitis B virus (HBV) clearance than IFN-alpha 2a and placebo, and IFN therapy may provide better long-term beneficial effects than placebo in terms of HBV clearance, reduction of HCC and prolonged survival.

Prospective randomized controlled study of interferon-alpha in preventing hepatocellular carcinoma recurrence after medical ablation therapy for primary tumors

BACKGROUND

Hepatocellular carcinoma (HCC) recurrence after ablation therapy for primary tumors is common.

METHODS

To evaluate the effectiveness of interferon-alpha (IFN-alpha) in preventing HCC recurrence, 30 eligible patients were randomized into three groups: 11 patients treated with three mega units (MU) of IFN-alpha three times weekly for 24 months (IFN-alpha-continuous group), 9 patients treated with 3 MU of IFN-alpha daily for 10 days every month for 6 months followed by 3 MU of IFN-alpha daily for 10 days every 3 months for a further 18 months (IFN-alpha-intermittent group), and 10 patients who received no IFN-alpha therapy (control group). The three groups were comparable in terms of etiology, demographics, and laboratory data at entry and HCC characteristics.

RESULTS

After a median follow-up of 27 months (range 4-53 months), 9 patients (90%) in the control group and 9 patients (45%) in 2 treatment groups (6 patients in the IFN-alpha-continuous group and 3 patients in the IFN-alpha-intermittent group) developed an HCC recurrence (P = 0.021). Cumulative HCC recurrence rates in the IFN-alpha-intermittent, IFN-alpha-continuous, and control groups were 22.2%, 27.3%, and 40% at the end of 1 year and 33.3%, 54.6%, and 90% at the end of 4 years (P = 0.0375), respectively (control vs. IFN-alpha-intermittent group, P = 0.0123; vs. IFN-alpha-continuous group, P = 0.0822). If both IFN-alpha groups were combined, the cumulative HCC recurrence rate of the patients treated with IFN-alpha and the control group was 25% and 40% at the end of 1 year and 47% and 90% at the end of 4 years, respectively (P = 0.0135).

CONCLUSIONS

The data suggested that IFN-alpha therapy may reduce HCC recurrence after medical ablation therapy for primary tumors.

Lymphoblastoid alpha-interferon in the prevention of hepatocellular carcinoma (HCC) in high-risk HbsAg-positive resected cirrhotic HCC cases: a 14-year follow-up

Hepatocellular carcinoma (HCC) is a leading cause of death worldwide. It is also a common long-term complication of chronic hepatitis B or C infections, with cirrhosis as a risk factor for premalignant development. Natural lymphoblastoid alpha-interferon (alpha N1-IFN) has been widely used in treating chronic HBV and HCV carriers. To investigate its long-term beneficial effect in reducing the development of HCC, 20 hepatitis B surface antigen (HBsAg) positive resected cirrhotic HCC patients who have undergone chemotherapy followed by long-term treatment of 3MU alpha N1-IFN daily for 10 days every 3 months were analyzed in a 14 year follow-up. Results indicated that these patients survived and remained free of HCC. In contrast, 10 other patients receiving chemotherapy alone after resection eventually had HCC recur. Similar recurrence of HCC was seen in patients who had either reduced dosage of alpha N1-IFN or stopped interferon therapy or received 30MU dose at 6-month intervals. Our findings indicate the therapeutic potential and long-term safety of alpha N1-IFN in suppressing the development of HCC in high-risk patients.

Interferon for preventing and treating hepatocellular carcinoma associated with the hepatitis B and C viruses

The possibility that interferon-alpha might be effective for the prevention or treatment of hepatocellular carcinoma is suggested by its efficacy against the associated hepatitis B and C viruses, by its efficacy in the treatment of some other human tumours, and by evidence that interferon-alpha may inhibit the growth of human hepatocellular carcinoma cell lines and their production of hepatitis B surface antigen. Few studies support the use of interferon-alpha for preventing hepatitis B virus-associated hepatocellular carcinoma. In contrast, benefit from the use of interferon-alpha to prevent hepatitis C virus-associated hepatocellular carcinoma is suggested in a large number of studies, but most of these studies have weaknesses of study design that preclude definitive conclusions. Nevertheless, most of these studies suggest that the incidence of hepatocellular carcinoma is lower in hepatitis C virus-infected patients receiving interferon-alpha, particularly in patients with a sustained response to interferon-alpha, compared to nonresponders. As a treatment for hepatocellular carcinoma, interferon-alpha was only evaluated in a small number of patients with advanced disease; 'partial responses' and prolongation of survival times in a few of these studies suggest that additional studies should be done in patients with less advanced disease.

Prevention of human hepatocellular carcinoma with natural lymphoblastoid alpha interferon

Hepatitis B surface antigen (HBsAg) positive hepatocellular carcinoma (HCC) patients have a high risk of recurrence within 5 years of hepatic resection and suitable long-term maintenance therapy is required. An open-ended controlled trial on 30 HBsAg positive Child Pugh's grade A cirrhotic patients was started in September 1986 using Wellferon (natural lymphoblastoid alpha interferon). Ten patients had standard adriamycin and mitomycin C monthly for 6 months, then discontinued when the course was completed. Twenty other patients had this regime, plus the addition of Wellferon given at 3 MU i.m. daily for 10 days. No HCC recurrence was observed in the interferon group. Followed to 14 years, 11 of the interferon-treated patients are still well and HCC free, whereas none of the chemotherapy patients are alive. High incidence of recurrence occurred in those who discontinued interferon (IFN), reduced the dose, or took the scheduled dose, but at longer intervals of more than 3 months. Wellferon, a natural alpha-IFN has potent inhibitory effects and reduces the risk of HCC development. It is a suitable agent for long-term maintenance prophylactic therapy for high-risk resected HBsAg positive HCC patients.

Role of antiviral therapy in the prevention of hepatocellular carcinoma

Infection with hepatitis B and/or hepatitis C virus is strongly associated with hepatocellular carcinoma (HCC). HCC likely develops through a sequence of chronic inflammation to fibrosis to cirrhosis and, eventually, dysplasia. Medical therapies aimed at the prevention of HCC are predicated on the interruption of this sequence by means of antiviral therapy. In this review, the authors summarize the available experience with prophylactic medical therapies and a number of questions that remain unanswered. Overall, although it appears that interferon-alpha therapy is beneficial in the prevention of HCC in patients with viral hepatitis, more experience is required before definitive recommendations can be made.

Recombinant interferon alfa 2b therapy in a patient with metastatic hepatocellular carcinoma

At present, there is no effective treatment of metastatic hepatocellular carcinoma (HCC). Systemic interferon alfa (IFN-alpha) was found to be of some use in patients with inoperable HCC in two randomized trials. We report a case in which metastatic HCC was cured by systemic IFN-alpha 2b in combination with surgery. A patient developed two bilateral pulmonary metastatic HCC nodules 5 months after the resection of the primary HCC. He was treated with systemic IFN-alpha 2b. One lesion completely disappeared. The other lesion showed an initial response but became resistant to the IFN-alpha 2b therapy after reduction in dosage because of the side effects. This was resected in view of the absence of new metastases after 9 months of IFN-alpha 2b therapy. He remained free from recurrence at 59 months of follow-up. A rare, but reversible, complication of retinal cotton wool spots caused by IFN-alpha 2b occurred in this patient. IFN-alpha 2b is partially effective in treating metastatic HCC. The time for its administration can also serve as an observation period, which is vital in deciding whether definitive surgical treatment of any residual lesions is indicated.

Prognostic factors for survival in patients with compensated cirrhosis and small hepatocellular carcinoma after percutaneous ethanol injection therapy

BACKGROUND

The objective of this study was to identify clinical, biochemical, ultrasound, and/or pathologic parameters capable of predicting survival in a cohort of patients with well compensated cirrhosis and small hepatocellular carcinoma (HCC) who were treated with percutaneous ethanol injection (PEI).

METHODS

The study group included 111 patients with Child--Pugh Class A cirrhosis and with one (93 patients) or two (18 patients) HCC nodules measuring < 5 cm in greatest dimension. All patients underwent multisession PEI. The prognostic values of pretreatment and post-treatment variables were analyzed using the Kaplan-Meier method.

RESULTS

The overall 3-year and 5-year survival rates of 62% and 41%, respectively, were not influenced by age, gender, duration of chronic hepatitis, serum albumin, prothrombin time ratio, total bilirubin, gamma-glutamyl transferase, hepatitis B surface antigen, antihepatitis C virus, HCC size, HCC ultrasound pattern, HCC histologic or cytologic grading, greatest spleen dimension, esophageal varices, or ascites. Levels of alpha-fetoprotein (AFP) > 14 ng/mL (P < 0.006), alanine aminotransferase > 75 IU/L (P < 0.04), and aspartate aminotransferase > 80 IU/L (P < 0.009) and platelet count < 92 x 10(9)/L (P < 0.02) before treatment were independent predictors of decreased survival. Among post-treatment parameters, AFP levels 6 months after PEI > 13.3 ng/mL (P < 0.003) and HCC recurrence in another segment of the liver (P < 0.04) were linked to decreased survival in univariate analysis.

CONCLUSIONS

Among patients with Child--Pugh Class A cirrhosis with small uninodular or binodular HCC who are treated with multisession PEI, those with elevated serum AFP and transaminase levels and low platelet count before treatment are characterized by decreased survival. During follow-up, intrahepatic recurrence of the tumor is the main factor affecting survival.

Interferon and prevention of hepatocellular carcinoma in viral cirrhosis: an evidence-based approach

BACKGROUND/AIMS

To evaluate by meta-analysis of available literature whether interferon (IFN) reduces the incidence of hepatocellular carcinoma (HCC) in patients with hepatitis B virus (HBV) or hepatitis C virus (HCV)-related Child A cirrhosis.

METHODS

Three randomized controlled trials and 15 nonrandomized controlled trials, including 4614 patients and comparing IFN to no treatment, were selected. Data on the incidence of HCC in IFN treated and untreated patients were extracted from each study. Meta-analysis by the DerSimonian and Laird risk difference (RD) method was used to pool observations.

RESULTS

A different incidence of HCC between treated and untreated cirrhotic patients was observed for HCV (overall RD -12.8%; 95% CI -8.3 to -17.2%, P < 0.0001) and HBV (overall RD -6.4%; 95% CI -2.8 to -10%, P < 0.001). In HCV-related cirrhosis, the rate of HCC development was lower in sustained responders to IFN than in untreated patients (overall RD -19.1%; 95% CI -13.1 to -25.2%, P < 0.00001), with low heterogeneity among trials (P=0.053), and also in nonresponders vs. untreated patients (overall RD -11.8%; 95% CI -6.4 to -19.1%, P < 0.0001), although with significant heterogeneity. Inconsistency among the studies was a major problem, both for HCV (chi2 = 58.16 with 13 DF; P < 0.0001) and HBV (chi2 = 26.4 with 6 DF; P = 0.0001) related cirrhosis, and also when follow-up was shorter than 60 months. Consistent results were only observed when assessing data from European reports: in this subgroup no preventive effect of HCC was shown for HBV (overall RD -4.8%; 95% CI -11.1-1.5%, P, not significant), and only a weak effect for HCV (overall RD -10%; 95% CI -5.9 to -14.2%; P < 0.0001).

CONCLUSIONS

Literature data pooling suggests a slight preventive effect of IFN on HCC development in patients with HCV-related cirrhosis. The magnitude of this effect is low and the observed benefit might be due to spurious associations. The preventive effect is more evident among sustained responders to IFN. IFN does not seem to affect the rate of HCC in HBV-related cirrhosis.

Use of interferon for prevention of hepatocellular carcinoma in cirrhotic patients with hepatitis B or hepatitis C virus infection

The incidence of hepatocellular carcinoma in North America is increasing. Current debate focuses on whether interferon administered to cirrhotic patients-with or without biochemical or virologic response-delays or prevents cancer of the liver. Review of the literature revealed several studies that showed improvement in or delay in progression of histologic fibrosis in patients with hepatitis C virus (HCV) infection. In patients with hepatitis B virus (HBV) infection, conversion to the nonreplicative stage may be associated with histologic improvement. However, only 11 studies (6 of HCV, 3 of HBV, and 2 of HCV and HBV) compared development of hepatocellular carcinoma in interferon-treated patients with cirrhosis and cirrhotic patients who were not treated with interferon. Although no firm statistical conclusions could be drawn, the literature suggests that interferon therapy may prevent hepatocellular carcinoma in patients with cirrhosis, particularly those infected with HCV. Interferon treatment cannot be recommended for all persons with cirrhosis and HBV or HCV infection because the current evidence is only suggestive. Long-term randomized, controlled trials may provide definitive data; however, it will be difficult, if not impossible, to conduct such trials because of the improved efficacy of combination therapy with interferon and ribavirin in patients with chronic HCV infection and the development of new therapies for patients with HBV infection.

Long-term results with interferon therapy in chronic type B hepatitis: a prospective randomized trial

OBJECTIVES

The aims of this long-term, prospective randomized study were to evaluate the clinical usefulness of alpha-interferon in treating chronic HBV infection and to establish whether clearance of viral replication markers and normalization of liver function tests induced by alpha-interferon were sustained.

METHODS

Sixty-four patients with chronic wild type (HBeAg-positive) hepatitis B, enrolled between 1983 and 1987, were randomized into two groups. Thirty-three patients received alpha-interferon (5 MU/m2 three times weekly for 6 months; treated group), and 31 were not treated (controls). Treated and control patients were prospectively followed for a mean of 86.4 +/- 6.96 and 79.7 +/- 6.8 (p = NS) months, respectively.

RESULTS

Clearance of the following viral markers was found in treated and control patients as follows: HBV-DNA, 26 (78.9%) and 18 (58.1%) (p = 0.106); HBeAg, 30 (90.9%) and 19 (61.2%) (p < 0.007); and HBsAg, 12 (36.4%) and three (9.8%) (p < 0.017). Persistent abnormal ALT levels were found in 11 (33.3%) treated and in 22 (70.9%) control patients (p < 0.025). Four control and three treated patients developed portal hypertension whereas two control and one treated patient developed hepatocellular carcinoma. Seven patients (five treated and two controls) were retrospectively found to have hepatitis C virus (HCV) coinfection before enrollment. To date, all coinfected patients remain positive for HCV-RNA. Also, all HCV coinfected patients, except one in the treated group, had persistent increased serum ALT levels. One of the coinfected patients developed portal hypertension.

CONCLUSIONS

Chronic HBV hepatitis patients responding to interferon treatment had a faster, more complete, and sustained clearance of viral markers than controls; HCV coinfection does not seem to negatively affect the clearance of HBV replicative markers. However when coinfection occurs, hepatic disease persists despite HBV marker clearance.

Long-term beneficial effect of interferon therapy in patients with chronic hepatitis B virus infection

To examine the long-term effect of interferon (IFN) therapy in patients with chronic hepatitis B virus (HBV) infection, particularly on survival and hepatocellular carcinoma (HCC) prevention, 101 male patients with chronic hepatitis B in a randomized controlled trial were followed up for 1.1 to 11.5 years after the end of therapy. Of the 101 patients, 34 patients received a placebo (control), and 67 patients were treated with IFN (31 patients were treated with IFN alone and 36 patients were treated with IFN after prednisolone priming). Follow-up studies included clinical, biochemical, and virological aspects and HCC screening every 3 to 6 months. Twenty-eight (42%) of the 67 IFN-treated patients and 8 (24%) of the 34 untreated patients seroconverted by the end of the trial. During follow-up, 22 (56%) of the 39 patients who did not seroconvert in the treated group and 5 (19%) of the 26 patients who did not seroconvert in the control group showed a delayed sustained response (P <.005). The cumulative incidence of sustained response was highest in the steroid priming group (P =.049 vs. the IFN-alone group; P =.028 vs. the control group). HCC was detected in 1 (1.5%) of the 67 treated patients and 4 (12%) of the 34 untreated patients (P =.043). The interval between entry and HCC detection was 3.5 to 8.2 years. The cumulative incidence of HCC development was significantly higher in the control group than in the treated group (P =.013). In contrast, the cumulative survival rate was higher in the treated group than the control group (P =. 018). Multivariate analysis showed that IFN therapy, preexisting cirrhosis, and the patient's age at entry are significant independent factors for both survival and HCC development. The results suggest that IFN has long-term beneficial effects in terms of HBV clearance, reduction of HCC, and prolonging survival.

Are all type I human interferons equivalent?

The Type I interferons are a family of closely related cytokines that have antiviral and immunostimulatory properties. There has been prolonged debate regarding the different interferon-alpha subtypes: with some authorities suggest that the different interferons have essentially similar properties but others argue that there are significant differences between them. Recent work has shown that the various interferon-alpha subtypes can interact with the interferon receptor components in different ways and can activate a number of different signalling pathways. Recent studies on the immunomodulatory properties of the Type I interferons indicate that there are profound differences between the subtypes. The clinical significance of all these differences remains to be determined.

Immunoprevention of cancer poses a challenge to pharmacological research

The evolving understanding of the molecular mechanisms of carcinogenesis establishes that the long latency period would offer numerous opportunities for intervention before the final step of fully developed malignancy has been reached. Immunoprevention of cancer may be a new approach to cancer control, by eliminating the cellular minimal deviations that are seen in the early phases of carcinogenesis. Available results of immunotherapy of preneoplastic lesions and data on anticarcinogenesis with immunoregulators in experimental models are in good accordance with theoretical expectations. However, clinical research on immunoregulators still focuses on the treatment of advanced cancer. The major problem hampering a wider application of immunoregulators in cancer prevention is the possibility of potential adverse effects, which are largely unknown. The promotion of future research in this area is essential. Moreover, the ethical issues of intervention trials in cancer must be discussed, by considering the potential psychological and social consequences.

Inhibition of the expression of hepatitis A and B viruses (HAV and HBV) proteins by interferon in a human hepatocarcinoma cell line (PLC/PRF/5)

AIMS/METHODS

PLC/PRF/5 is a continuous human hepatocarcinoma cell line whose genome contains integrated HBV DNA and which secretes two of the hepatitis B virus envelope proteins (HBs and PreS2). This line is also susceptible to infection by hepatitis A virus and was therefore used to compare the effects of interferon on protein synthesis of these two viruses and to assess the interactions which occur between them during infection.

RESULTS

Results showed that recombinant interferon alpha 2-a inhibited the expression of the two hepatitis B virus envelope antigens (HBs and PreS2) and of the only hepatitis A virus antigen in a dose-dependent fashion. Comparison of the effect of interferon on antigenic protein production of these two viruses, showed stronger inhibition of hepatitis A virus capsid antigen than of hepatitis B virus envelope antigens. Infection with hepatitis A virus also downregulates the expression of the two hepatitis B virus proteins.

CONCLUSIONS

Considering the absence of cytotoxic effects from the doses used, this study confirms the relevance of this cellular model for the study of antiviral cytokines in vitro. It also provides a further rationale for the clinical evaluation of the therapeutic potential of interferons in severe hepatitis cases due either to hepatitis A virus alone or to superinfection of hepatitis B virus carriers by hepatitis A virus.

Interferons in precancer and cancer prevention: where are we?

Clinical research on interferons (IFN) still focuses on the treatment of advanced cancer. The research strategy eventually must be reevaluated. The cellular minimal deviations that are seen in early phases of carcinogenesis might be the most rational target for immune interventions. That biologic response modifiers have considerable capacity to prevent induction and development of malignant neoplasias has been demonstrated in several animal systems. Even the few clinical studies available at present on the treatment of preneoplastic lesions with IFN have definitely shown more success than those involving treatment of advanced tumors. In addition, there is experimental evidence that IFN might be suitable candidates for immunoprevention. The major problems hampering a wider application of IFN in immunoprevention is that they cause adverse effects. Unfortunately, we do not know much about the specific mechanisms involved in the immune control of human tumor development during the initial and the latency phases of carcinogenesis. More research is needed in this area. In this article the state of the art of using IFN for treating preneoplastic lesions is reviewed, and also we report some of our experimental results on IFN and anticancerogenesis.

Alpha interferon treatment may prevent hepatocellular carcinoma in HCV-related liver cirrhosis

BACKGROUND/AIMS

The aims of alpha-interferon treatment for chronic viral liver infections are clearance of the virus and healing of the disease. Hepatocellular carcinoma is a complication of viral cirrhosis; but it is not yet known whether treatment of viral cirrhosis with alpha-interferon prevents this complication.

METHODS

The incidence and the risk (Cox regression analysis) of developing hepatocellular carcinoma were calculated in 347 patients with hepatic cirrhosis; 227 (34 hepatitis B virus and 193 hepatitis C virus related) were treated with alpha-interferon and 120 (28 hepatitis B virus and 92 hepatitis C virus) did not receive this treatment, in order to evaluate the efficacy of alpha-interferon in the prevention of hepatocellular carcinoma. In all patients, the cirrhosis was well compensated (Child A).

RESULTS

Over mean follow-up periods of 49 months for hepatitis B virus and 32 months for hepatitis C virus, 20/347 patients (6/62 hepatitis B virus and 14/285 hepatitis C virus) developed hepatocellular carcinoma. The risk of developing this tumor was significantly greater in males (p < 0.007) and in patients not treated with alpha-interferon (p < 0.01). The Relative Risk of developing hepatocellular carcinoma increased significantly (p < 0.0002) with each passing year. In patients with hepatic cirrhosis secondary to hepatitis B virus infections, the risk did not seem to be modified by alpha-interferon treatment, even though a greater, but not significant risk (Relative Risk = 4.9; p = 0.3) was calculated for untreated patients; in contrast, in hepatitis C virus-related cirrhosis, this risk was reduced by a factor of 4.0 (p = 0.04). The tumor developed only in non-responder patients regardless of virus type. After adjustment for confounding factors (sex, age, alcohol consumption, cigarette smoking), a statistically significant (p < 0.025) effect of interferon treatment in preventing hepatocellular carcinoma was still demonstrated when responders were matched with controls, but not when responders were compared with non-responders.

CONCLUSIONS

These results show that, in addition to its ability to halt the progression of viral-induced liver disease, alpha-interferon is also of benefit in patients with hepatitis C virus cirrhosis who respond to this treatment by lowering their risk of developing hepatocellular carcinoma.