Hepatitis B Virus Reactivation After Withdrawal of Preemptive Antiviral Therapy in Hematologic Malignancy

Previous studies dealt with patients who maintained antiviral drugs for 2 \~ 6 months after final chemotherapy and they revealed that many of the patients who stopped preemptive antiviral drug within 6 months experienced viral reactivation. Based on the study results, guidelines recommend that preemptive antiviral therapy should be maintained for at least 6 months. Nevertheless, many clinicians apply the preemptive antiviral drugs for 1\~2 years or longer after final chemotherapy without definite evidences, and this practice increases the medical expenditure a lot. Therefore, the investigators are going to find out the proper and safe duration of preemptive antiviral therapy which can be a good reference in the future practice.