Risk of Hepatitis B Reactivation Among ALL Patients With Occult Hepatitis B Infection

Anticancer therapy increases the risk of hepatitis B virus (HBV) reactivation in patients with occult hepatitis B infection (OHBI), particularly in those who receive rituximab or stem-cell transplantation. However, the exact risk of HBV reactivation in patients with ALL/lymphoblastic lymphoma (LBL) receiving prolonged, intensive myelosuppressive chemotherapy is not known and thus the role of antiviral prophylaxis is not clearly established.

This prospective observational study was conducted at a single tertiary cancer center in India (October 2017 to August 2021). Patients age 15 years and older with ALL/LBL were screened for OHBI and enrolled. Liver function tests and HBV DNA levels were monitored at baseline, during treatment, and throughout follow-up phase. During episodes of hepatitis, extended serology panel was performed. The primary end point was the incidence of HBV reactivation.

OHBI was identified in 30.4% (172/566) of patients treated at our center during the study period. In the prospective cohort, 65 patients with ALL/LBL and OHBI, treated on a pediatric-inspired protocol, were enrolled. HBV reactivation occurred in six patients (9.2%; 95% CI, 4.3 to 18.7), none of whom developed HBV-related hepatitis. Seventeen patients experienced at least one episode of grade ≥3 hepatitis, with a median AST of 401 U/L (range, 192-3,490) and ALT of 430 U/L (range, 255-1,950). Hepatitis led to chemotherapy delays in five patients, with a median delay of 15.5 days (range, 7-39).

Our findings indicate a moderate to high risk of HBV reactivation in ALL/LBL patients with OHBI treated with pediatric-inspired protocols, particularly during maintenance, supporting prophylactic antiviral therapy as standard practice in regions with high or intermediate HBV endemicity.