[Intra-epithelial cancer of the anal canal. Pathogenic study apropos of 5 cases]

Anal carcinomas are rare and their precancerous conditions are not well known. Two populations at risk are described, elderly women and, recently, homosexual males. Early detection of dysplastic lesions or intraepithelial carcinoma in the anal mucosa could lead to preservation on the anal sphincter and consequently to improvement of quality of survival. The present study included 3 women and 2 men. The pathological examination of the surgical specimens in these 5 cases (hemorrhoidal procidence, rectal prolapsus, fibrous polyps, fissure) showed, in all cases, an intraepithelial carcinoma developed in the squamous epithelium of the anal canal. In one of the 5 cases, the anal lesion was concomitant with an intraepithelial carcinoma of the uterine cervix. Complete local resection of the lesions were performed in all cases, associated with complementary radiotherapy in one patient. On follow-up, we observed one recurrence after 8 months in one out of 5 patients. All patients are alive. Histogically, the specimens showed an intraepithelial carcinoma in all 5 cases, with a microinvasive carcinoma in one case. The transitional mucosa of the anal canal showed dysplatic modification in all cases. Immunohistochemical study of the 5 cases did not discern the papilloma virus antigene. In the one case where it was performed, molecular hybridization showed a type 33 papillomavirus. The risk factors of anal carcinomas seems to be changing, in particularly the incidence is increasing in the homosexual patients. In this particular population, as in the uterine cervix, the human papilloma virus is probably one of the main etiological factors. The management of these lesions is not well-defined.(ABSTRACT TRUNCATED AT 250 WORDS)