A case-control study of Hodgkin's disease in Brazil II. Seroepidemiologic studies in cases and family members.

A case-control study of antibody titers to the viral capsid antigen of Epstein-Barr virus was carried out in 70 patients with Hodgkin's disease (HD) and in 92 siblings, 50 parents and 19 children of the HD patients, each paired with a control matched for age and sex. The geometric mean titer (GMT) of the HD patients was significantly greater than that of the controls (t69 = 6.30, p < 0.0005), and the proportion of HD cases with titers greater than or equal to 1:320 was significantly elevated (35.5% vs. 2.9%). No significant differences in GMTs were found when the HD patients were grouped by sex or by histologic subtype. An inverse correlation between age and titer was noted among HD patients but not among controls. The GMT of the 161 relatives of the HD cases was similar to that of their respective controls. Likewise, there was no significant elevation of the GMT of the subset consisting of family members of HD patients with high titers when compared to controls. However, when the GMT of the family members of HD patients with high titers was compared to that of the relatives of the HD patients with low titers, a significant difference was found (t159 = 2.54, p < 0.01).