HIGH-GRADE ANAL DYSPLASIA IN VISUALLY NORMAL MUCOSA IN HOMOSEXUAL MEN- 7 CASES

Background: Anal cancer and anal human Papillomavirus (HPV) infection are increased in homosexual men. Methods: We screened high risk homose xual men as part of a longitudinal study examining the effect of HIV i nfection on the risk of development of high grade anal intraepithelial neoplasia (ALN II,III). Results: We found seven men who had histologi cal evidence of ALN II-III with visually normal findings by anoscopy. Two men were HIV-seronegative, five were HIV-seropositive, and only on e of the HIV-seropositive men had a low CD4 count < 200. Abnormal cyto logical results seen over follow-up periods of 3 months to 2.5 yr sugg est the persistence of visually inapparent anal abnormalities. Two of the men had had small internal warts at earlier examinations, and thre e of the seven men subsequently developed visually abnormal anal findi ngs. All men had HPV 16 DNA detected at some point Conclusions: We hyp othesize that high grade anal neoplasia may develop deep in the glands and can be detected by cytology before visible lesions are detected e ven with the aid of a colposcope. However, the implications of finding high grade anal cytology are not known at this time. Natural history studies are ongoing.