Solution: This case takes some inductive reasoning and some of the history is purposefully left out. Specifically, as can be determined by the appearance of the colon (thick walled with few haustra and fatty infiltration of the wall, particularly in the rectosigmoid region), the patient has a history of ulcerative colitis. In addition, there is a large mass in the splenic flexure and an associated intussusception can be seen on image 3. The constellation of findings and symptoms suggests a colonic adenocarcinoma that has developed in the setting of UC and that is associated with an acute intussusception. Patients with UC are of course at increased risk of colon cancer.