Impact of an Epstein-Barr Virus Serology-Based Screening Program on Nasopharyngeal Carcinoma Mortality: A Cluster-Randomized Controlled Trial

Abstract

PURPOSE Screening for nasopharyngeal carcinoma (NPC) has shown an improvement in early detection and survival rates of NPC in endemic regions. It is critical to evaluate whether NPC screening can reduce NPC-specific mortality in the population. METHODS Sixteen towns in Sihui and Zhongshan cities, China, were selected; eight were randomly allocated to the screening group and eight to the control group. Residents age 30-69 years with no history of NPC were included from January 1, 2008, to December 31, 2015. Residents in the screening towns were invited to undergo serum Epstein-Barr virus (EBV) viral capsid antigen/nuclear antigen 1-immunoglobulin A antibody tests; others received no intervention. The population was followed until December 31, 2019. Nonparametric tests and Poisson regression models were used to estimate the screening effect on NPC mortality, accounting for the cluster-randomized design. The trial is registered with ClinicalTrials.gov (identifier: NCT00941538 ). RESULTS A total of 174,943 residents in the screening group and 186,263 residents in the control group were included. NPC incidence and overall mortality were similar between the two groups. A total of 52,498 (30.0% of 174,943) residents participated in the serum EBV antibody test. The overall compliance rate for endoscopic examination and/or biopsies among baseline and ever-classified high-risk participants was 65.9% (1,110 of 1,685) and 67.6% (1,703 of 2,518), respectively. A significant 30% reduction in NPC mortality was observed in the screening group compared with the control group (standardized NPC-specific mortality rate of 8.2 NPC deaths per 1,000 person-years versus 12.5; adjusted rate ratio [RR], 0.70 [95% CI, 0.49 to 0.997]; P = .048). This benefit was most evident among individuals age 50 years and older (RR, 0.56 [95% CI, 0.37 to 0.85]; P = .007) compared with those younger than 50 years (RR, 0.96 [95% CI, 0.64 to 1.46]; P = .856). CONCLUSION In this 12-year trial, EBV antibody testing resulted in a significant reduction in NPC mortality.