Abstract: A 89-year-old male patient developed a plaque an the right margin of the anus for 8 years, then gradually spread to the anal canal 1 year age. During operation the skin lesion was observed to have extended to the anal canal and the rectum. Histopatholagical exarninatian showed the same kind of carcinoma cells, i.e.,Paget's cells in the anal canal tumor as well as the skin lesion. Electron microscopic study of the Paget's cells of the anal margin showed features of glandular celis. The clipical manifestations, histoiogic changes, and use of mucin stain suggest that this is a continuous process, an extension of the extramammary Paget's disease from the akin into the anai canal and rectum.

Key words: Paget’s disease, extramammary