Low rates of hepatitis B virus screening at the onset of chemotherapy.

PURPOSE: Patients with hepatitis B virus (HBV) infection are at risk for reactivation after chemotherapy. Effective prophylaxis is available but depends on detection of prior infection. Previous studies have shown low screening rates, but no large-scale US studies have been conducted. We sought to determine predictors of screening and positive HBV test results in patients receiving chemotherapy.
METHODS: We conducted a retrospective cohort study of patients with newly diagnosed cancer who received chemotherapy between January 2004 and September 2007 at a comprehensive cancer center. We determined rates and predictors of screening for HBV infection with HB surface antigen (HBsAg) and antibody to hepatitis B core antigen (anti-HBc) tests as well as the prevalence and predictors of positive results. We explored rates of acutely elevated liver function tests and liver decompensation after chemotherapy.
RESULTS: Of 10,729 new patients who received chemotherapy, 1,787 (16.7%) underwent HBsAg or anti-HBc screening. Less than 20% of patients with HBV risk factors were screened, even though their odds of HBV infection were increased four-fold compared with those without risk factors. The prevalence of chronic HBV infection was 1.5%. whereas 7.4% had positive anti-HBc only. The strongest predictors of HBV screening were having a history of HBV infection, hematologic malignancy, and rituximab treatment (P < .001). Asian ethnicity was not a significant predictor of screening, despite being a strong and highly significant predictor of positive test results (P < .001).
CONCLUSION: HBV screening among patients with cancer is low, especially among those known to be at high risk for HBV infection. Future research directed toward identifying best screening methods and HBV risk tools will be necessary to reduce the risk of reactivation of HBV infection after chemotherapy.