Analysis of baseline hepatitis B virus DNA levels in chronic hepatitis B patients with non-hematological malignancies prior to the initiation of cancer chemotherapy

Abstract

Abstract. Reactivation of hepatitis B virus (HBV) infectionis common (~20-50%) during cancer chemotherapy. Baseline HBV replication status is an important risk factor for HBV reactivation. To date, data on the baseline HBV DNA level for chronic hepatitis B (CHB) patients prior to chemotherapy, particularly for non-hematological malignancies, are limited. A total of 105 consecutive CHB patients with solid tumors who received prophylactic antiviral therapy prior to chemotherapy from November, 2011 to December, 2014, were enrolled in this study. The patients' tumors included: Breast cancer (37.1%), lung cancer (18.1%), colon cancer (17.1%), head and neck cancer (10.5%), other gastrointestinal tract malignancies (8.6%), gynecological cancer (4.8%) and others (3.8%). The mean age of the enrolled patients was 55.2±1.1 years, 48 of the patients were male, 3 were hepatitis B e antigen-positive, and 26.7% had abnormal alanine aminotransferase (ALT) levels at baseline. The median HBV DNA level measured by quantitative polymerase chain reaction assay prior to chemotherapy was 3.30 log 10 IU̸ml and 49.5% of the enrolled patients had a baseline HBV DNA level >2,000 IU̸ml. A wide range of HBV distribution was found: <20 IU̸ml (15.2%), 20≤DNA<2,000 IU̸ml (35. 3%), 2 , 0 0 0 ≤ D N A< 2 0, 0 0 0 I U̸ m l (2 6. 6%), 20,000≤DNA<106 IU̸ml (17.2%) and <10 6 IU̸ml (5.7%). Age and baseline ALT level were not strongly associated with virological activity. The mean HBV DNA and the percentage of patients with HBV DNA >2,000 IU̸ml were comparable between different cancer groups. Quantitative HBsAg level was a major determinant of baseline HBV DNA, and a significant correlation was noted between log 10 hepatitis B surface antigen and log 10 HBV DNA levels (γ=0.641, P<0.001). Our study demonstrated a wide distribution of baseline HBV DNA level among CHB patients diagnosed with non-hematological malignancies. Of note, approximately half of the patients (i.e., those with HBV DNA >2,000 IU̸ml) had a higher risk of HBV reactivation if no appropriate antiviral prophylaxis was undertaken.