Hepatitis B is a health condition caused by hepatitis B virus (HBV), associated with high morbidity and mortality. HBV can integrate into the host genome via covalently closed circular DNA (cccDNA) and may reactivate under immunosuppressive conditions such as cancer treatment. The objective of this study was to evaluate the prevalence of HBV infection in oncologic patients and to characterize this population demographically. Retrospective study of adult oncology patients in a specialized health service between 2010 and 2023, who underwent serology for anti-HBc, the marker of prior exposure to HBV. Linear regression analysis was used to evaluate anti-HBc prevalence over time, and multivariate logistic regression to assess the association of demographic characteristics with reactive anti-HBc. Ethnicity/skin color was based on self-identification. During the study period, 125,985 oncologic patients were seen, and 28,869 underwent anti-HBc testing. The prevalence of HBV infection was 13.4% (n = 3,857). There was a statistically significant reduction in prevalence over time, from 16.5% in 2010 to 9.9% in 2023. In multivariate analysis, male patients (34.6% of the sample) had an 89% higher likelihood of being anti-HBc reactive compared with females (OR = 1.89; 95% CI: 1.76–2.04; p < 0.001). Patients aged ≥ 60 years had a 4.40-fold higher likelihood of being reactive compared with those ≤ 40 years (OR = 4.40; 95% CI: 3.77–5.12; p < 0.001). White patients represented 61.4% of the population; the others (mixed race, Black, Indigenous, and Asian) were categorized as non-white (19.2%). Non-white patients had a 25% higher chance of being anti-HBc reactive compared with white patients (OR = 1.25; 95% CI: 1.15–1.35; p < 0.001). This study demonstrated a significant prevalence of HBV infection in the oncologic population (13.4%), higher than in the general population, and associated with male sex, age ≥ 60 years, and non-white ethnicity/skin color. Despite the decreasing trend over time, prevalence remained elevated (9.9%) in 2023. The data may support public health actions aimed at prevention and control of HBV infection in oncologic populations.
Pinto et al. (Sun,) studied this question.