Outcome of Multiple Myeloma Patients With Hepatitis B Surface Antigen: Korean Multiple Myeloma Working Party 2103 Study.

Background: Hepatitis B virus reactivation (HBVr) is a well-known complication of systemic chemotherapy for particularly hematologic malignancies in HBV carriers. We performed a multicenter retrospective study to investigate the incidence and risk factors of HBVr in patients with hepatitis B surface antigen (HBsAg)-positive multiple myeloma (MM).

Methods: We included 123 patients with HBsAg-positive MM who had received systemic therapy. The primary objective of the study was to evaluate the incidence of HBVr in patients with HBsAg-positive MM.

Results: The median age was 59 years, and 72 patients were male. With a median follow-up duration of 41.4 months, there were 43 instances of HBVr in 35 patients (28.5%): 29 treatment-related HBVr occurred during 424 treatments. Treatments containing antiviral prophylaxis were associated with a significantly lower incidence of HBVr compared to those without (14.4% vs. 1.9%, P < 0.001). Moreover, treatment with cyclophosphamide (P = 0.002) and doxorubicin (P = 0.053) were risk factors for HBVr; stem cell transplantation was not associated with HBVr. There was no significant difference in overall survival between patients with and without HBVr (P = 0.753) and myeloma progression was the major cause of death.

Conclusion: Considering the low incidence of HBVr in patients who had received antiviral prophylaxis, HBsAg-positivity should not impede patients from receiving optimal antimyeloma treatment or participating in clinical trials.