RESUMEN
Despite the relatively common incidence of sacrococcygeal dermoids, rectal or vaginal cysts are uncommon. We report a case of a dermoid cyst occurring in the ischiorectal space. A 42-years-old woman visited our hospital because of anal pain. Computed tomography showed a well-circumscribed cystic mass of about 9 9 8 cm along the ischiorectal space abutting the vagina and occupying almost the entire pelvic cavity. The resected tumor was a cyst entirely covered with a firm, fibrous, capsule, which was filled with an amorphous white creamy substance. The histological findings showed that the cyst consisted of a keratinizing stratified squamous epithelium with sebaceous glands, which was compatible with a benign cystic teratoma. The patient had an uneventful postoperative course and was discharged from the hospital 5 days after the opreation.