CD79A and nasopharyngeal carcinoma: Using a VCA-IgA ≥1:40 or both VCA-IgA- and EA-IgA-positive (cutoff = 1:5) as the threshold for nasopharyngeal endoscopy and/or pathological examination referral following NPC screening, the 5-year cumulative probability of seroconversion was 55.5% [95% confidence interval (CI) 49.4%–61.6%] for the participants with an initial VCA-IgA-positive status and 20.6% (95% CI 12.4%–28.8%) for the participants with an initial VCA-IgA-negative status.