Anal smear test to diagnose occult anorectal infection with human papillomavirus in men.

Sir, Infection of the female genital tract with human papillomavirus (HPV) has assumed increasing importance since the cytological recognition of an occult form (non-condylomatous) indicated that its true prevalence is much higher than previously suspected. ' 2 Indeed its role as a possible aetiological agent (or co-factor) in the development of cervical, vulval, and vaginal squamous cell carcinoma has been postulated.3 Recent identification of deoxyribonucleic acid (DNA) sequences of herpes simplex virus (HSV) subtypes in tumours 4 (Zur Hausen H, personal communication) and of humoral markers in serum 5 of patients with cervical cancer have lent credence to the hypothesis. The biology of tumour development has not been ascertained, although association with recognised oncogenic "permissive" factors of immune deficiency in kidney transplant recipients has been described.6 Recent demonstration of the acquired immune deficiency syndrome (AIDS) and lesser immunosuppression in homosexual men, and the associated instances of viral opportunism in this group,7 the high incidence of HSV,8 and the knowledge that condylomata are common, have led us to initiate a study to determine the incidence of non-condylomatous HPV infection of the anal canal by cytological means. Sporadic cases of anorectal cancer in homosexual men, occurring in a younger age group than usual, have been described, and the worldwide increasing incidence and mortality of invasive squamous cell cancer in young women (under 40 years) 9 10 (often with an explosive course) would lead us to expect a possible similar increase in this group of men, 30-40% of whom may have some form of immune deficiency.7 205