Rare anorectal pathologic conditions.

Among the rare anorectal pathologic conditions published in the literature since 1992, except for malignant pathology, we have taken an interest in anal dermatology with Hailey-Hailey disease; infectious diseases, including tuberculosis, gangrene, actinomycosis, and cytomegalovirus ulcerations; vascular pathology with rectal varices and tumoral pathology with leiomyomas and lipomas; embryologic disorders, including gastric and salivary heterotopia; and a few exceptional lesions, such as spontaneous hematomas and certain traumatic lesions.