ASSOCIATION OF SERUM IMMUNOGLOBULIN-G ANTIBODIES AGAINST HUMAN PAPILLOMAVIRUS TYPE-16 CAPSIDS WITH ANAL EPIDERMOID CARCINOMA

Background: Anal epidermoid carcinoma is a relatively rare tumor, but its incidence has been increasing rapidly during the past few years, G enetic material from the major oncogenic types of human papillomavirus (HPV), types 16 and 18, has regularly been demonstrated in a substant ial proportion of anal cancers, suggesting an etiologic role of HPV in fection, Recently, serum antibodies against HPV type 16 capsids were s hown to be a serologic measure of HPV16 infection. Purpose: We investi gated whether serum antibodies against HPV16 capsids are associated wi th an increased risk of developing anal cancer, Methods: Serum samples from 64 patients (48 women and 16 men) with untreated anal epidermoid cancer and from 79 age- and sex-matched healthy blood donors were ana lyzed for the levels of serum immunoglobulin G (IgG) against capsids o f HPV16 by the enzyme-linked immunosorbent assay, The levels of serum IgG against HPV type 6 and bovine papillomavirus (BPV) capsids, as wel l as against HPV16 peptide antigens, were also measured, Results: Wher eas antibodies against HPV6 or BPV capsids were not significantly asso ciated with anal cancer, the presence of IgG against HPV16 capsids exc eeding the anti-BPV antibody levels was demonstrated among 55% (35 of 64) of the case patients but only among 4% (three of 79) of the contro l subjects (odds ratio [OR] 30.4; 95% confidence interval [CI] = 8.4-1 61.5), Antibodies against HPV16 E2 and E7 peptides were also more comm on among case patients (OR = 12.8 and 95% CI = 5.4-31.5 for E2; OR = 3 .0 and 95% CI = 1.4-6.7 for E7), Conclusion: The results suggest that HPV16 capsid antibodies are serologic markers for anal cancer, Implica tion: Exposure to HPV16 or related viruses appears to be a major risk factor in the majority of anal cancers.