[Analysis of the incidence of low viral load/low-level viremia and its associated factors in patients with HBV-related primary liver cancer]

Objective: To retrospectively analyze the viral levels and associated factors in patients with hepatitis B virus (HBV)-related primary liver cancer (PHC) in real-world settings and further explore the correlation between low viral load (LVL) and/or low-level viremia (LLV) and PHC. Methods: Five hundred twenty-four cases with HBV-related PHC with complete pathologically confirmed data from 2013 to 2020 were included. Percentages (%) were used to express their viral load, antiviral (oral) status, patient compliance, presence or absence of cirrhosis, family history of liver cancer, and others. LVL definition: After excluding detection errors by PCR method, serum HBV DNA <50-2 000 IU/ml, and those who had received antiviral drug treatment were called LLV. Antiviral treatment (AVT) rate definition: As of the confirmed diagnosis of PHC, those who had been regularly treated using oral antiviral drugs for six months or more (≥6 months). Results: General situation: The ratio of male to female enrolled patients was 15.90:1 (493/31). Patients aged >40 years accounted for 91.98% (482 cases). Hepatitis B surface antigen (HBsAg) positivity condition: The ratio of HBsAg-positive to HBsAg-negative/anti-HBc-positive (HBsAg-/anti-HBc+) PHC patients was 5.89:1 (448/76). Among the 76 HBsAg-/anti-HBc+patients, the ratio of HBsAg-/anti-HBs+/anti-HBc+ to HBsAg-/anti-HBs-/anti-HBc+ patients was 0.95:1 (37/39). Hepatitis B e antigen (HBeA) positivity condition: The ratio of HBeAg-negative to HBeAg-positive cases was 3.23:1 (400/124). HBV DNA level condition: The medical history records of 75.00% of patients (393/524) had traceable HBV DNA test reports. Out of 393 patients, 45.04% (177/393) accounted for undetectable HBV DNA, 13.49% (53/393) accounted for LVL, 41.48% (163/393) accounted for HBV DNA exceeding the upper limit of LVL, and 4.07% (16/393) accounted for LLV. Among HBsAg-positive and HBsAg-/anti-HBc+ patients, the HBV DNA positivity rates were 59.12% (214/362) and 6.45% (2/31), respectively. Antiviral treatment condition: Among the 448 HBsAg-positive PHC patients, the total AVT rate was 18.08% (81/448), of which seven patients did not have their HBV DNA results traced back. Among them, the AVT rate of 148 patients with HBV DNA lower than the lowest detection value was 41.22% (61/148); the AVT rate of 53 patients with LVL was 18.87% (10/53); and the AVT rate of 163 patients with HBV DNA≥LVL upper limit was 1.84% (3/163). Liver cirrhosis and family history condition: 348 patients (66.41%) had liver cirrhosis. 67 patients (12.79%) had a distinct family history of HBV-related liver cirrhosis and liver cancer. Alpha-fetoprotein (AFP) condition: 514 patients underwent AFP testing, with 30.93% of the patients had normal AFP levels, and 69.07% had AFP levels exceeding the upper limit of normal values (355/514). Among them, 10 μg/L<AFP<400 μg/L and>400 μg/L accounted for 34.44% (177/514) and 34.63% (178/514), respectively. Tissue typing condition: 99.05% (519/524) were hepatocellular carcinoma, and well-differentiated and moderately differentiated cases accounted for only 8.59%. Conclusions: In the real world, comprehensive, timely screening, standardized, and effective antiviral treatment have not yet been achieved for patients with chronic hepatitis B, resulting in the persistence of HBsAg and/or HBV DNA positivity (especially LVL and/or LLV). Although LVL does not account for a high proportion among all HBV-related PHC populations, the vast majority of LVL populations have not received any antiviral treatment. In addition, some PHC populations with HBV DNA>2 000 IU/ml have not received standard antiviral treatment before the onset of the disease, which should be paid attention to. At the same time, HBsAg-/anti-HBc+ populations may have latent HBV infection and may even progress to PHC. Notably, PHC may still occur after HBeAg seronegative conversion.