Published online May 7, 2014. doi: 10.3748/wjg.v20.i17.4980
Revised: October 24, 2013
Accepted: November 12, 2013
Published online: May 7, 2014
AIM: To search for the answer in extensive ulcerative colitis as to whether histological inflammation persisting despite endoscopic mucosal healing serves to increase the risk of colon cancer (CC) or high grade dysplasia (HGD).
METHODS: This is a single center (Lenox Hill Hospital) retrospective cohort and descriptive study of extensive ulcerative colitis (UC) for 20 years or more with a minimum of 3 surveillance colonoscopies and biopsies performed after the first 10 years of UC diagnosis. Data analyzed included: duration of UC, date of diagnosis of (CC) or (HGD), number of surveillance colonoscopies, and biopsies showing histological inflammation and its severity in each of 6 segments when endoscopic appearance is normal. Two subgroups of patients were compared: group 1 patients who developed CC/HGD and group 2 patients who did not develop CC/HGD.
RESULTS: Of 115 patients with longstanding UC reviewed, 68 patients met the inclusion criteria. Twenty patients were in group 1 and 48 in group 2. We identified the number of times for each patient when the endoscopic appearance was normal but biopsies nevertheless showed inflammation. Overall, histological disease activity in the absence of gross/endoscopic disease was found in 31.2% (95%CI: 28%-35%) of colonoscopies performed on the entire cohort of 68 patients. Histological disease activity when the colonoscopy showed an absence of gross disease activity was more common in group 1 than group 2 patients, 88% (95%CI: 72%-97%) vs 59% (95%CI: 53%-64%). Only 3/20 (15%) of patients in group 1 ever had a colonoscopy completely without demonstrated disease activity (i.e., no endoscopic or histological activity) as compared to 37/48 (77%) of patients in group 2, and only 3.3% (95%CI: 0.09%-8.3%) of colonoscopies in group 1 had no histological inflammation compared to 23% (95%CI: 20%-27%) in group 2.
CONCLUSION: Progression to HGD or CC in extensive ulcerative colitis of long standing was more frequently encountered among those patients who demonstrate persistent histological inflammation in the absence of gross mucosal disease. Our findings support including the elimination of histological inflammation in the definition of mucosal healing, and support this endpoint as an appropriate goal of therapy because of its risk of increasing dysplasia and colon cancer.
Core tip: Patients with long standing and extensive ulcerative colitis who develop colon cancer rarely have histological healing despite gross endoscopic healing. The persistence of histological inflammation is common in those who develop colon cancer (CC) or high grade dysplasia (HGD). When surveillance colonoscopies in ulcerative colitis of 20 years duration reveal persistent histological inflammation, patients are at high risk for the development of CC/HGD. Consideration of increasing drug therapy should arise, and the patient is entitled to share in this knowledge and contribute to the decision.