Estimating the key outcomes and hepatocellular carcinoma risk in patients in immune-tolerant phase of chronic hepatitis B virus infection: A systematic review and meta-analysis.

The question of whether patients in the immune-tolerant (IT) phase of chronic hepatitis B virus (HBV) infection should undergo antiviral therapy and determine the optimal regimen remains unclear. A comprehensive search of PubMed, Embase, MEDLINE, Cochrane Library, and Wanfang Data from inception to 5 December 2023, was conducted. Studies reporting on key outcomes such as HBV DNA undetectability, HBeAg loss or seroconversion, HBsAg loss or seroconversion, and hepatocellular carcinoma (HCC) incidence in patients in the IT phase of chronic HBV infection were included. In total, 23 studies were incorporated. Approximately 4% of patients in the IT phase achieved spontaneous HBeAg loss over 48 weeks of follow-up. Antiviral therapy demonstrated a favourable impact on HBV DNA negative conversion (Children: risk ratios [RR] = 6.83, 95% CI: 2.90-16.05; Adults: RR = 25.84, 95% CI: 6.47-103.31) and HBsAg loss rates (Children: RR = 9.49, 95% CI: 1.74-51.76; Adults: RR = 7.35, 95% CI: 1.41-38.27) for patients in the IT phase. Subgroup analysis revealed that in adult patients in the IT phase, interferon plus nucleos(t)ide analogues (NA)-treated patients exhibited a higher pooled rate of HBsAg loss or seroconversion than those treated with NA monotherapy (9% vs. 0%). Additionally, the pooled annual HCC incidence for patients in the IT phase was 3.03 cases per 1000 person-years (95% CI: 0.99-5.88). Adult patients in the IT phase had a significantly lower HCC incidence risk than HBeAg-positive indeterminate phase patients (RR = 0.46, 95% CI: 0.32-0.66), with no significant differences observed between IT and immune-active phases. Presently, there is insufficient evidence solely based on reducing the risk of HCC incidence, to recommend treating patients in the IT phase of chronic HBV infection. However, both adult and paediatric patients in the IT phase responded well to antiviral therapy, showing favourable rates of HBsAg loss or seroconversion.

The incidence of hepatocellular carcinoma and clearance of hepatitis B surface for CHB patients in the indeterminate phase: a systematic review and meta-analysis.

Background: Nearly 30%-40% of patients with chronic hepatitis B do not fall into any of the traditional natural history classification and thus are classified as indeterminate. However, it is unclear whether patients in the indeterminate phase (IP) are at a higher risk for hepatocellular carcinoma (HCC) than those in the defined phases (DP) and would benefit from antiviral therapy. We performed a systematic review and meta-analysis of HCC incidence and HBsAg clearance among patients in the IP versus DP. Methods: We defined the clinical phases as per the AASLD 2018 hepatitis B guidance. We searched PubMed, Embase, Medline, and Web of Science for relevant studies that reported HCC incidence or HBsAg clearance in IP versus DP patients published between January 2007 and March 2023. Annual HCC incidence and HBsAg clearance rates were pooled using a random/common-effects model. Results: We analyzed data from 14 studies, comprising 7798 IP patients (222 patients developed HCC and 239 achieved HBsAg clearance) and 10,725 DP patients. The pooled annual HCC incidence was 2.54 cases per 1,000 person-years (95% CI, 1.14-4.39) and HBsAg clearance rate was 12.36 cases per 1,000 person-years (95% CI, 10.70-14.13) for the IP patients. IP patients were associated with significantly higher HCC incidence risk (RR = 1.64, 95% CI, 1.34-2.00) and slightly lower annual HBsAg clearance rate (RR = 0.83, 95% CI, 0.70-0.99) than the DP patients. In addition, HBeAg-negative IP patients (2.31%; 95% CI, 0.87-4.45) showed a significantly higher HCC incidence than those who were HBeAg positive (0.00%; 95% CI, 0.00-0.99) (p< 0.001). The Asia-Pacific region IP patients (4.30%; 95% CI, 2.07-7.27) were also associated with a higher HCC incidence versus Europe (0.05%; 95% CI, 0.00-1.39) (p< 0.001). However, there were no significant differences between different strategies (treated vs. untreated: 2.56%; 95% CI, 1.01-4.63 vs. 1.61%; 95% CI, 0.00-5.81, p = 0.09), and heterogeneity was substantial across the studies (I2 = 89%). Conclusion: The systematic review and meta-analysis showed a high HCC incidence and low HBsAg clearance among patients in the IP, especially for HBeAg-negative patients and the Asian population. We emphasize that future multicenter prospective cohort studies or randomized trials are needed to verify if expanding antiviral therapy for patients in the IP is associated with reduced HCC risk or good treatment outcomes.