title: Cancer risk in ulcerative colitis: why are results in the literature so varied?
mesh_terms: D003082:Colectomy; D003093:Colitis, Ulcerative / Q000150:complications*; D003110:Colonic Neoplasms / Q000453:epidemiology* / Q000209:etiology; D005500:Follow-Up Studies; D006801:Humans; D012306:Risk; D013997:Time Factors