Changing trend of Epstein-Barr virus association in Hodgkin lymphoma in the Republic of Korea.

Hodgkin lymphoma (HL) in resource-poor population shows an early childhood peak with predominance of mixed cellularity (MCHL) and high Epstein-Barr virus (EBV) association, whereas HL in resource-rich population has a peak in ages 15-29 years with the predominance of nodular sclerosis (NSHL) and low EBV association. We examined the changing trend of HL in association with EBV in Korea in 385 cases of HL (1980-2011). Data from 1980-1995 and 1996-2011 were compared. Age distribution showed a marked decrease in children (age < 15 years) (21.0 % to 8.6 %, p = 0.004) and sharp increase in young adults (ages 15-29 years) and ages 30-59 years. Male predominance decreased from 3.04 to 1.57. Predominant subtype changed from MCHL to NSHL; MCHL fell from 53.3 % to 26.4 % (p < 0.001), and NSHL rose from 24.8 % to 58.2 % (p < 0.001). EBV-positive HL decreased from 66.7 % to 38.2 %. However, in young adult females, EBV positive cases increased, contributing to the peak in this age group. Epidemiology of HL in Korea is rapidly changing into a Western pattern concurrent with the socioeconomic changes. Analysis of the cases stratified by EBV status and sex identified a smaller hidden peak in the young adult age, which confirms the four disease hypothesis proposed by Jarrett. We propose EBV testing as an essential component in epidemiologic study of Hodgkin lymphoma.