COST-EFFECTIVENESS OF HEPATITIS B VIRUS SCREENING BEFORE ADJUVANT CHEMOTHERAPY IN PATIENTS WITH EARLY STAGE BREAST CANCER

Purpose: Hepatitis B virus (HBV) remains an enormous global public health problem. Most individuals have clinically silent disease. Cytotoxic chemotherapy causes reactivation in 30% of hepatitis B surface antigen positive patients. This can be severe and even fatal and may also lead to interruption of chemotherapy. HBV screening before adjuvant chemotherapy for breast cancer seems to be a plausible strategy.  The objective of this study is to estimate the health and economic effects of HBV screening strategies.

Method: We developed a state-transition microsimulation model to examine the cost-effectiveness of 3 HBV screening strategies: (1) “No screening”; (2) “Screen all and treat” with lamivudine/tenofovir (LAM/TDF); (3) “Screen all and treat” with entecavir (ETV) for 55 year-old breast cancer patients undergoing adjuvant chemotherapy. In the model, health states were constructed to reflect the natural history of breast cancer and chronic hepatitis B (CHB).    Breast cancer health states included on chemotherapy, disease free, local relapse, treated relapse and distant relapse.  CHB health states incorporate serology, inflammation, viral load and clinical states (cirrhosis, hepatocellular carcinoma (HCC), etc.).  Model data were obtained from the published literature.  We used a payer perspective, a lifetime time horizon, and used a 5% discount rate.

Result:   Screen all and treat would prevent at least 43 severe reactivations, 51 non-severe reactivations, 9 deaths from reactivation, 22 chemotherapy interruptions, 4 episodes of decompensated cirrhosis, 5 HCCs, and 6 HBV-related deaths per 100,000 persons screened over the lifetime of the cohort at a HBV seroprevalence of 0.4%.   Screen all and treat with LAM/TDF was associated with an increase of 0.00368 QALYs and cost C$116 more per person, translating to an ICER of C31,518/QALY gained compared with “No screening”.   Screen all and treat with ETV was associated with an increase of 0.00424 QALYs and cost C$217 more per person, translating to an ICER of C$51,276/QALY gained compared with “No screening” (Table 1).  Results of sensitivity analyses provided evidence that the “Screen all and Treat” would likely to be cost-effective taking into consideration the uncertainty.

Conclusion:   Our analysis suggested that HBV screening before adjuvant chemotherapy for breast cancer patients would prevent a significant number of reactivations, and is likely be cost-effective.  Identification of silent CHB infection with the offer of treatment when appropriate can extend the lives of patients at reasonable cost.