Hormonal Contraceptives, Human Papillomavirases and Cervical Cancer; Some Observations from a Colposcopy Clinic

EDITORIAL COMMENT: The importance of hormonal contraception, at individual, national and international levels can hardly be exaggerated, especially now that intrauterine devices are in disfavour because of complications, and the litigation thus engendered. There have been many studies seeking evidence of a relationship between hormonal contraception and carcinoma of the cervix and breast, but overall the findings are negative, although all are agreed that unopposed oestrogen administration (without progestogen supplementation on a monthly or 6‐monthly basis) increases the risk of endometrial carcinoma by a factor of 2–5. It is against this background that the findings in this study must be viewed — it provides an early warning, if not the first, that there may be an association between oral contraception and the prevalence of human papillomavirus (HPV) infection in women with carcinoma in situ (CIN III) of the cervix. The recent literature contains a plethora of papers concerning the diagnosis of HP V infection and the relationship of various types to development of CIN and invasive cervical cancer. Cytology, colposcopy, cervical histology and now DNA probing are the methods available for the diagnosis of HPV infection. The first 3 methods correlate fairly well in most studies and in Chang's series HPV was diagnosed by microscopic examination of cervical biopsies. However DNA probing gives a much higher prevalence of HPV infection than the other methods (approximately 100% in patients with CIN III and 10%‐15% in asymptomatic patients with normal cytology) which if true, suggests that such a high proportion of the community harbour the virus that sexual transmission cannot be the exclusive mode of infection — an important point to be settled since diagnosis often raises the spectre of which partner introduced the pathogen into the relationship. The takeaway message from this paper is that the most reliable method of diagnosis of HPV infection should be used to answer the question of whether or not hormone contraception predisposes to HPV infection. If the editor is allowed to guess the result of this necessary exercise it is that the contraceptive pill does not increase the risk of HPV infection and its sequelae. How else can one explain the falling incidence, in all age groups, of invasive cervical cancer in NSW reported elsewhere in this issue by Mc‐Credie et al. It is unlikely that there is on the one hand an epidemic of HPV infection, and on the other a steadily falling prevalence of the disease it causes, regardless of the conservative treatment of CIN with or without associated HPV infection, by local ablative therapy. Summary: Observations from a colposcopy clinic from 1982–1985 are presented and show that in women with histologically proven precancerous lesions, those using hormone contraception had a significantly higher infection rate with human papillomavirus (HPV). Hormone contraception was preferred by younger women. Because information relating to sexual behaviour was not available for analysis, the findings in this study need to be interpreted with caution. The association of HPV and cervical cancers is well established. If hormonal contraceptive use and simultaneous HPV infection are associated with cervical neoplasia, and laboratory evidence supports this thesis, then further urgent investigations are needed for the implications are grave.