HBV (Hepatitis B Virus) — oncology-focused definition
HBV is a partially double-stranded DNA virus (Hepadnaviridae) that infects hepatocytes and can cause chronic hepatitis, leading to cirrhosis and hepatocellular carcinoma (HCC).Oncology relevance (for pharmacists):
- Oncogenic role:
- Chronic HBV infection causes ongoing hepatic inflammation, fibrosis, and genomic instability.
- HBV DNA integration into the host genome contributes to malignant transformation, even without cirrhosis.
- Strongly associated with hepatocellular carcinoma, especially in endemic regions.
Clinical significance in cancer patients:
- HBV reactivation risk during chemotherapy, anti-CD20 antibodies (e.g., rituximab), stem cell transplant, and high-dose corticosteroids.
- Reactivation can lead to fulminant hepatitis, liver failure, treatment interruption, and death.
Pharmacist-specific implications:
- Mandatory HBV screening before systemic anticancer therapy:
- HBsAg, anti-HBc ± anti-HBs
- Antiviral prophylaxis recommended for at-risk patients:
- Preferred agents: entecavir or tenofovir
- Continue antivirals during treatment and for ≥6–12 months after immunosuppression (longer with anti-CD20 therapy).
Key takeaway for oncology pharmacists:HBV status directly affects treatment safety, prophylaxis decisions, and monitoring, making pharmacist intervention critical to prevent HBV reactivation and associated morbidity.
Synonyms
HBV