Risk classification of HBV reactivation after immunosuppressive therapy. The vertical axis shows the HBV infectious status at baseline according to serum HBV markers before immunosuppressive therapy. The horizontal axis shows the intensity of immunosuppression after immunosuppressive therapy. The incidence of HBV reactivation in HBsAg-positive patients who received systemic chemotherapy, rituximab + steroid-containing chemotherapy, or HSCT has been reported to be 24%–53%, 59%–80%, and >50%, respectively. In patients with resolved HBV infection (anti-HBc-positive and/or anti-HBs-positive in HBsAg-negative patients), the incidence of HBV reactivation has been reported to be 1%–3% after systemic chemotherapy, 10%–24% (by retrospective study) and 9%–11% (by prospective study) after rituximab + steroid-containing chemotherapy, and 14%–20% after HSCT. HBsAg-negative patients seronegative for anti-HBc and anti-HBs (all marker-seronegative at baseline) are considered to be at no risk for HBV reactivation after immunosuppressive therapy. This figure is modified and cited from Kusumoto et al⁷  with permission from The Japanese Society of Hematology.