Question: A 69-year-old Japanese man was referred to the Department of Oral and Maxillofacial Surgery in our hospital because of a chronic oral ulcer in the gingiva, which was initially suspected to be a gingival carcinoma. He had been administered mesalamine and corticosteroids for the treatment of ulcerative colitis over the past 5 years. He experienced spontaneous bleeding and severe pain in the upper gingiva 2 months before his visit to our hospital, and he had difficulty eating. Although he experienced diarrhea a few times per day, his colitis symptoms remained stable.