Seroepidemiological studies on carcinoma of the nasopharynx.

Abstract

Summary In the period of a 1.5-year retrospective study on nasopharyngeal carcinoma (NPC) in Taiwan, sera collected from NPC patients, age- and sex-matched neighborhood (N) controls, NPC families, and neighborhood control families were titrated for antibodies of herpes-type virus (HTV) in a Burkitt9s lymphoma cell line (P3HR-1) by the indirect immunofluorescence antibody technique. Dissociations in the frequency distributions of antibody titers in NPC and the control groups were maximum when the limiting value was set at 1:640. Antibody titers were higher in NPC patients than in any of the three control groups by geometric means and significantly different by ridit analysis. Of 321 NPC patients, 55% had anti-HTV antibody titers equal to or higher than 1:640. Such values occurred in only 6% of the three control groups. No sex difference in the percentages of “seropositive” cases in all the groups was evident. The distributions of anti-HTV antibody titers between cases of NPC and each of the three control groups were significantly different. The relative risks indicated that persons with an antibody titer equal to or higher than 1:640 had a NPC risk more than 40 times that of those with an antibody titer of less than 1:40. There were no significant differences in the geometric means and distributions of anti-HTV antibody titers of family members of NPC patients and N controls by the same titer of probands. The geometric means of anti-HTV antibody titers of the family members by different titers of probands, however, were higher for the both groups as the titer of the probands were higher, and the distributions were significantly different for the both groups. There were no household aggregations of high titers of anti-HTV antibody in both family members of NPC patients and N controls. The significance and implications of these findings are discussed.