ASCO Provisional Clinical Opinion for Hepatitis B Virus Screening Before Cancer Therapy: Are These the Right Tests in the Right Patients?

Abstract

Hepatitis B virus (HBV) reactivation is a well-documented complication of cancer treatment that can cause serious morbidity and mortality. A systematic review from 2008 reported reactivation probabilities between24%and88%,withhigher ratesofHBVreactivationamong patients with hematologic malignancies. Subsequent reports have reported an especially high risk of reactivation among patients receiving anti-CD20 therapy and/or stem-cell transplantation (SCT). Small randomized controlled trials and prospective cohort studies suggest thatHBVreactivation rates canbe reduced tonear zerowith theuseof prophylacticantiviralmedication. However, studiesofHBVscreening suggest varied uptake in cancer clinics. Clear clinical guidelines are required, and the revised ASCO Provisional Clinical Opinion (PCO) on HBV screening before cancer therapy is welcomed. As outlined in Table 1, the new PCO recommends that when HBV screening is pursued, both HB surface antigen (HBsAg) and HB core antibody (anti-HBc) be tested. It also recommends against screening all patients for HBV before cancer treatment (universal screening). Instead, selective HBV screening is recommended, except for patients receiving antiCD20 therapies or SCT, in which case universal HBV screening is favored. In our view, these recommendations open the door to both overdiagnosis of so-called resolved HBV (HBsAg negative/anti-HBc positive) of uncertain clinical significance in patients with solid tumors, and underdiagnosis of clinically important HBV infection (HBsAg positive) in patients receiving cancer treatments other than anti-CD20 or SCT. Our perspective is consistent with the dissenting opinion of two authors on the ASCO PCO panel, who suggested that universal screening is preferable to the risk-adapted approach.