Antibodies to Epstein-Barr Virus-Related Antigens in Nasopharyngeal Carcinoma. Comparison of Active Cases With Long-Term Survivors

Summary

Sera from nasopharyngeal carcinoma (NPC) patients before treatment (BT) and from those who had survived 4-8 years after radiation therapy were titrated for antibodies to Epstein-Barr virus (EBV) capsid antigens (VCA) and to the D (diffuse) and R (restricted) components of the early antigen (EA) complex. The geometric mean anti-VCA and anti-D titers in the BT group increased substantially with progression of NPC from stage I to V. Anti-D was almost exclusively the dominant antibody to the EA complex, preventing detection of low anti-R levels which probably were also present. The long-term survivors (LTS), who initially had NPC in stages I-IV, had generally lower anti-VCA titers than the BT group. Compared to BT patients, fewer patients in the LTS group showed anti-D, usually at low titers, and many more revealed low to moderate levels of anti-R as the dominant or sole antibody to the EA complex. The apparent declines in anti-VCA and anti-D in LTS were seen regardless of the stage of disease before radiation therapy. Thus, in contrast to the BT group, no significant stage-related increments in serologic activities were evident in LTS, except that those with initially stage IV NPC tended to have somewhat higher titers than those treated at an earlier stage. These results suggest that the anti-VCA and anti-D titers decline gradually in apparently tumor-free LTS and that anti-D eventually becomes nondetectable.