Figure 2.

The patient’s clinical course. Serum HBsAg was negative, and HBV-DNA was present at 2.6 log copies/mL before chemotherapy. Entecavir (ETV) was used during R-THP-COP chemotherapy and the subsequent 14 months. Serum HBV-DNA levels remained undetectable, and serum gammaglobulin levels were within the normal range. ETV was discontinued at 14 months after the end of chemotherapy. However, serum HBV-DNA became positive at 24 months and increased to 3.3 log copies/mL at 27 months. In addition, serum HBsAg also reverted. After restarting ETV at 28 months, serum HBV-DNA and HBsAg immediately turned negative. Anti-HBs became positive for the first time at 31 months and remained positive at 46 months, whereas ETV was re-discontinued at 36 months.