Impact of age and gender on risk of hepatocellular carcinoma after hepatitis B surface antigen seroclearance

Systematic review of risk factors of hepatocellular carcinoma after hepatitis B surface antigen seroclearance

There is no consensus about factors that increase risk of hepatocellular carcinoma (HCC) among patients with chronic hepatitis B who have achieved seroclearance of hepatitis B surface antigen (HBsAg). To assess the available evidence about risk factors for HCC after HBsAg seroclearance, Scopus, EMBASE, PubMed and Cochrane Library databases were systematically searched for relevant studies published through 15 September 2017. A total of 28 studies involving more than 105 411 patients with chronic hepatitis B were included. HBsAg seroclearance occurred spontaneously in 7656, while it occurred after interferon or nucleos(t)ide analogue therapy in 1248. The rate of HBsAg seroclearance was 6.77%. Incidence of HCC was significantly lower among patients who experienced HBsAg seroclearance than among those who remained HBsAg-positive (1.86% vs 6.56%, P < .001). Risk factors of HCC occurrence included cirrhosis (incidence with vs without: 9.51% vs 1.66%), male gender (2.34% vs 0.64%) and age ≥ 50 year at HBsAg seroclearance (2.34% vs 0.63%) (all P < .001). The available evidence suggests that HCC can develop at a low rate after HBsAg seroclearance, so periodic surveillance is recommended, especially for male patients, patients with cirrhosis and patients who experience HBsAg seroclearance when at least 50 years old.

Cellular Genomic Sites of Hepatitis B Virus DNA Integration

Infection with the Hepatitis B Virus (HBV) is one of the strongest risk-factors for liver cancer (hepatocellular carcinoma, HCC). One of the reported drivers of HCC is the integration of HBV DNA into the host cell genome, which may induce pro-carcinogenic pathways. These reported pathways include: induction of chromosomal instability; generation of insertional mutagenesis in key cancer-associated genes; transcription of downstream cancer-associated cellular genes; and/or formation of a persistent source of viral protein expression (particularly HBV surface and X proteins). The contribution of each of these specific mechanisms towards carcinogenesis is currently unclear. Here, we review the current knowledge of specific sites of HBV DNA integration into the host genome, which sheds light on these mechanisms. We give an overview of previously-used methods to detect HBV DNA integration and the enrichment of integration events in specific functional and structural cellular genomic sites. Finally, we posit a theoretical model of HBV DNA integration during disease progression and highlight open questions in the field.

Effects of Diabetes and Glycemic Control on Risk of Hepatocellular Carcinoma After Seroclearance of Hepatitis B Surface Antigen

BACKGROUND & AIMS

Diabetes is associated with a 2-fold increase in risk of hepatocellular carcinoma (HCC) among patients with chronic hepatitis B virus (HBV) infection. However, we know little about the effect of diabetes on HCC risk after seroclearance of hepatitis B surface antigen (HBsAg). We evaluated the effect of diabetes and glycemic control on HCC development after HBsAg seroclearance in a population-wide study in Hong Kong.

METHODS

We performed a retrospective study of 4568 patients with chronic HBV infection who cleared HBsAg from January 2000 through August 2016, using the Clinical Data Analysis and Reporting System of the Hospital Authority, Hong Kong. We collected and analyzed data on patient demographics, comorbidities, medications, laboratory test results, and subsequent development of HCC. The presence of diabetes was defined by International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code, with level of hemoglobin A1c (HbA1c) above 6.5%, fasting glucose level of 7 mmol/L or more, or treatment with any antidiabetic agent.

RESULTS

We identified 1560 patients with diabetes; 29 patients (1.9%) developed HCC after a median follow-up time of 3.4 years (interquartile range, 1.5-5.0 years). Diabetes was associated with increased risk of HCC after adjustment of age, sex, presence of cirrhosis, and the use of medications (adjusted hazard ratio, 1.85; 95% CI, 1.04-3.28; P = .036). Among patients with diabetes, time-weighted average level of HbA1c was an independent risk factor for HCC, after adjustment for age at clearance, use of statins, and other important covariates (adjusted hazard ratio: 1.51; 95% CI, 1.20-1.91; P < .001). A time-weighted average level of HbA1c of 7% or more was associated with a higher 5-year cumulative incidence of HCC (4.0%) than a time-weighted average HbA1c level below 7% (1.8%; log-rank test P = .035).

CONCLUSIONS

In a population-based analysis of patients with chronic HBV infection in Hong Kong, we found diabetes to be an independent risk factor for HCC after HBsAg seroclearance. However, glycemia control appears to reduce the risk of HCC.

Potential use of serum HBV RNA in antiviral therapy for chronic hepatitis B in the era of nucleos(t)ide analogs

Although the efficacy of nucleos(t)ide analogue (NA) has been confirmed for treatment of chronic hepatitis B, long-term therapy has been recommended due to the high frequency of off-therapy viral DNA rebound and disease relapse. In this review, the RNA virion-like particles of hepatitis B virus (HBV) are integrated into the life cycle of HBV replication, and the potential significance of serum HBV RNA is systematically described. The production of HBV RNA virion-like particles should not be blocked by NA; in this regard, serum HBV RNA is found to be a suitable surrogate marker for the activity of intrahepatic covalently closed circular DNA (cccDNA), particularly among patients receiving NA therapy. Therefore, the concept of virological response is redefined as persistent loss of serum HBV DNA and HBV RNA. In contrast to hepatitis B surface antigen (HBsAg) that can originate from either the cccDNA or the integrated HBV DNA fragment, serum HBV RNA, with pregenomic RNA origination, can only be transcribed from cccDNA. Therefore, the loss of serum HBV RNA would likely be a promising predicator for safe drug discontinuation. The clinical status of consistent loss of serum HBV RNA accompanied with low serum HBsAg levels might be implicated as a "para-functional cure," a status nearly close to the functional cure of chronic hepatitis B, to distinguish the "functional cure" characterized as serum HBsAg loss with or without anti-HBs seroconversion.

Letter: older age and male gender increase the risk of hepatocellular carcinoma after hepatitis B surface antigen (HBsAg) seroclearance

This article is linked to Liu et al paper. To view this article visit https://doi.org/10.1111/apt.13634.

Durability of hepatitis B surface antigen seroclearance in untreated and nucleos(t)ide analogue-treated patients

BACKGROUND & AIMS

It is uncertain if nucleos(t)ide analogue (NA)-induced hepatitis B surface antigen (HBsAg) seroclearance is durable. We investigated the impact of hepatitis B surface antibody (anti-HBs) and duration of consolidation antiviral therapy on the durability of HBsAg seroclearance.

METHODS

A territory-wide cohort study was conducted using data from the Hospital Authority, Hong Kong. We identified all subjects with positive HBsAg between January 1, 2000 and August 31, 2016. NA use, liver biochemistries, serial HBsAg and anti-HBs results were retrieved. The primary endpoint was confirmed HBsAg seroclearance, defined least two negative HBsAg test results, with the last HBsAg test being negative in patients with chronic hepatitis B (CHB).

RESULTS

A total of 4,080 CHB patients were included for analysis. In patients with spontaneous HBsAg seroclearance (n=3,563), 1,771 patients (49.7%) had confirmed HBsAg seroclearance and 75 patients (2.1%) had HBsAg seroreversion. In patients with NA-induced HBsAg seroclearance (n=475), 320 patients (67.4%) had confirmed HBsAg seroclearance and 14 patients (2.9%) had HBsAg seroreversion. The five-year cumulative probability of confirmed HBsAg seroclearance was comparable in patients with spontaneous and NA-induced HBsAg seroclearance (88.1% vs. 92.2%; Log-rank test, p=0.964); it was also similar in patients with or without anti-HBs in NA-treated patients (95.4% vs. 95.5%, Log-rank test, p=0.602). HBsAg seroreversion was only observed in 3 (2.0%) patients who had received consolidation therapy for 6-12months and none of those who had received it for ≥12months.

CONCLUSIONS

NA-induced HBsAg seroclearance is as durable as spontaneous HBsAg seroclearance. NA-treated patients may not need to have positive anti-HBs before stopping treatment. Longer consolidation NA treatment may result in more durable HBsAg seroclearance.

LAY SUMMARY

We investigated 4,080 patients with hepatitis B surface antigen (HBsAg) seroclearance. HBsAg seroreversion occurred in 2.1% of patients with spontaneous and 2.9% of those with nucleos(t)ide analogues-induced HBsAg seroclearance.

Relationship between serum HBV-RNA levels and intrahepatic viral as well as histologic activity markers in entecavir-treated patients

BACKGROUND & AIMS

In diagnostics, serum hepatitis B virus (HBV)-RNA levels are valuable when the HBV-DNA load in circulation is effectively suppressed by nucleos(t)ide analogue (NUC) therapy. This study aimed to determine the intrahepatic viral replication activity reflected in serum HBV-RNA and whether HBV-RNA contributes to liver histological changes in patients treated with NUC.

METHODS

A cross-sectional set of serum and liver biopsy samples was obtained from patients treated with entecavir, who had undetectable levels of serum HBV-DNA. The correlations between serum HBV-RNA concentration and levels of peripheral and intrahepatic viral replicative forms, as well as histological scores, were analyzed. Quasispecies of serum HBV-RNA and intrahepatic viral replicative forms were examined by deep sequencing. HBV-RNA-positive hepatocytes were visualized by in situ hybridization.

RESULTS

Serum HBV-RNA was detected in 35 of 47 patients (74.47%, 2.33-4.80log10copies/ml). These levels correlated not only with the intrahepatic HBV-RNA level and the ratio of intrahepatic HBV-RNA to covalently closed circular DNA (cccDNA), but also with the histological scores for grading and staging. Regarding quasispecies, serum HBV-RNA was dynamic and more genetically homogenous to simultaneously sampled intrahepatic HBV-RNA than to the cccDNA pool. In situ histology revealed that HBV-RNA-positive hepatocytes were clustered in foci, sporadically distributed across the lobules, and co-localized with hepatitis B surface antigen.

CONCLUSION

Serum HBV-RNA levels reflect intrahepatic viral transcriptional activity and are associated with liver histopathology in patients receiving NUC therapy. Our study sheds light on the nature of HBV-RNA in the pathogenesis of chronic HBV infection and has implications for the management of chronic hepatitis B during NUC therapy.

LAY SUMMARY

Serum HBV-RNA levels are indicative of the intrahepatic transcriptional activity of covalently closed circular DNA and are associated with liver histological changes in patients with chronic B hepatitis who are receiving nucleos(t)ide analogue therapy.