Paget's disease of the anal margin.

A follow-up study of 22 patients with Paget's disease of the anal margin was conducted to determine the prevalence of invasive disease and coexisting visceral carcinomas, cure and survival rates. Seventy-three per cent of the patients suffered from persistent pruritus ani. Seven (32 per cent) patients had malignancy (invasive Paget's disease (n = 5) and coexisting visceral carcinoma (n = 2] and six (27 per cent) developed malignancy (invasive Paget's disease (n = 4) and coexisting visceral carcinoma (n = 2] during follow-up, giving an overall occurrence of malignancies of 59 per cent (95 per cent confidence limits: 36-79). The median follow-up period was 9 (range 0.5-25) years. No difference in length of history could be found between patients with or without malignancy. The estimated cure rate by actuarial analysis among radically treated patients was 64 per cent (95 per cent confidence limits: 43-91) at 1 year and 45 per cent (95 per cent confidence limits: 18-72) at 8 years after primary treatment. The 5- and 10-year crude survival rates of 54 per cent and 45 per cent, respectively, were significantly lower than the corresponding values of 84 per cent and 60 per cent for the normal population (P less than 0.01). Patients with persistent pruritus ani and a perianal skin lesion should be biopsied frequently. If Paget's disease is diagnosed, physical examination of the patient and anorectal region must be done carefully and repeatedly.