Key points
- Before any systemic cancer treatment, test HBsAg, anti-HBc (total or IgG) and anti-HBs [1].
- HBsAg-positive: antiviral prophylaxis before or with treatment, until at least 12 months after it ends [1].
- HBsAg-negative and anti-HBc-positive with rituximab or another anti-CD20 drug, or transplant: antiviral prophylaxis [1].
- Entecavir or tenofovir; lamivudine is not preferred because of resistance [2, 3].
Risk groups
| Risk | Examples | Action |
|---|---|---|
| High (more than 10%) | Anti-CD20 drugs (rituximab, obinutuzumab) in HBsAg-positive or anti-HBc-positive patients; anthracyclines or prolonged high-dose corticosteroids in HBsAg-positive patients | Antiviral prophylaxis |
| Moderate (1 to 10%) | TNF inhibitors, TKIs and conventional chemotherapy in HBsAg-positive patients; anthracyclines with isolated anti-HBc | Antiviral prophylaxis or monitoring (per guideline) |
| Low (less than 1%) | Methotrexate, azathioprine or short-term corticosteroids | Usually monitoring |
Monitoring and duration
- HBsAg-positive: before starting, HBV DNA and liver enzymes; hepatology advice in active chronic hepatitis [1, 3].
- Isolated anti-HBc without an anti-CD20 drug: if you do not give prophylaxis, check HBsAg and HBV DNA every 1 to 3 months and start treatment immediately if they turn positive [1].
- Duration: at least 12 months after the last chemotherapy dose, and longer after anti-CD20 treatment or transplant; continue monitoring after stopping [1, 3].
References
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Numbers in the text, such as [1], refer to these sources. Sources with a “Study card” button are summarised in the site’s evidence library.
- 1
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- 3
This page is based on reputable scientific sources and was last updated on 28 October 2026. The content of this website is for educational and informational purposes only and does not replace consultation, diagnosis or treatment by a specialist physician. Consult your treating physician about any treatment decision.
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