A Rare Case of Colonic Leiomyosarcoma in Association with Ulcerative Colitis

Abstract

Ulcerative colitis (UC) is known to be associated with an increased risk of colorectal cancer. However, the occurrence of non-epithelial malignancies is uncommon. An elevated lesion in the descending colon was found in a 51-year-old woman with a 30-year history of UC. Despite tumor progression, repeated biopsies showed no cancerous findings. Because the lesion was highly suspected to be a malignant tumor, a partial colectomy was performed. The pathological diagnosis was leiomyosarcoma. Leiomyosarcoma of the gastrointestinal tract is rare, and this is only the third known case reported in patients with UC.