BACKGROUND & AIMS: Evidence suggests that mesalamine-based anti-inflammatory medicines may prevent colorectal cancer (CRC) in ulcerative colitis (UC). If mesalamine exerts its chemopreventive effect by its anti-inflammatory activity, then other medications that reduce colitis activity also should possess chemopreventive properties. Our aim was to determine the effect of the immunomodulators 6-mercaptopurine (6MP) and azathioprine (AZA) in preventing the development of dysplasia or CRC in UC. METHODS: Patients with UC who underwent a surveillance colonoscopy in 1996-1997 were identified from a gastrointestinal pathology database. A proportional hazards analysis assessing 6MP/AZA use as a time-changing covariate was performed to evaluate the effect of 6MP/AZA on: (1) progression to any neoplasia (low-grade dysplasia, high-grade dysplasia, or CRC), and (2) progression to advanced neoplasia (high-grade dysplasia or CRC). RESULTS: A total of 315 subjects met inclusion criteria and were followed for an average of 8 years from their first surveillance examination. There were no significant differences in rates of progression to advanced neoplasia or to any neoplasia between 6MP/AZA users and never-users by log-rank testing. The proportional hazards analysis resulted in hazard ratios of 1.06 (95% confidence interval, .59-1.93) and 1.30 (95% confidence interval, .45-3.75) when considering the effect of exposure to 6MP/AZA on progression to any or to advanced neoplasia, respectively. The results were unaffected by known potential confounders. CONCLUSIONS: In UC patients with no initial history of dysplasia, 6MP/AZA use appears to have little or no effect on the rate of neoplastic transformation in the colon. Importantly, the use of 6MP/AZA did not increase malignant transformation in UC.
BACKGROUND & AIMS: Evidence suggests that mesalamine-based anti-inflammatory medicines may prevent colorectal cancer (CRC) in ulcerative colitis (UC). If mesalamine exerts its chemopreventive effect by its anti-inflammatory activity, then other medications that reduce colitis activity also should possess chemopreventive properties. Our aim was to determine the effect of the immunomodulators 6-mercaptopurine (6MP) and azathioprine (AZA) in preventing the development of dysplasia or CRC in UC. METHODS:Patients with UC who underwent a surveillance colonoscopy in 1996-1997 were identified from a gastrointestinal pathology database. A proportional hazards analysis assessing 6MP/AZA use as a time-changing covariate was performed to evaluate the effect of 6MP/AZA on: (1) progression to any neoplasia (low-grade dysplasia, high-grade dysplasia, or CRC), and (2) progression to advanced neoplasia (high-grade dysplasia or CRC). RESULTS: A total of 315 subjects met inclusion criteria and were followed for an average of 8 years from their first surveillance examination. There were no significant differences in rates of progression to advanced neoplasia or to any neoplasia between 6MP/AZA users and never-users by log-rank testing. The proportional hazards analysis resulted in hazard ratios of 1.06 (95% confidence interval, .59-1.93) and 1.30 (95% confidence interval, .45-3.75) when considering the effect of exposure to 6MP/AZA on progression to any or to advanced neoplasia, respectively. The results were unaffected by known potential confounders. CONCLUSIONS: In UC patients with no initial history of dysplasia, 6MP/AZA use appears to have little or no effect on the rate of neoplastic transformation in the colon. Importantly, the use of 6MP/AZA did not increase malignant transformation in UC.
Authors: Christopher Andrew Lamb; Nicholas A Kennedy; Tim Raine; Philip Anthony Hendy; Philip J Smith; Jimmy K Limdi; Bu'Hussain Hayee; Miranda C E Lomer; Gareth C Parkes; Christian Selinger; Kevin J Barrett; R Justin Davies; Cathy Bennett; Stuart Gittens; Malcolm G Dunlop; Omar Faiz; Aileen Fraser; Vikki Garrick; Paul D Johnston; Miles Parkes; Jeremy Sanderson; Helen Terry; Daniel R Gaya; Tariq H Iqbal; Stuart A Taylor; Melissa Smith; Matthew Brookes; Richard Hansen; A Barney Hawthorne Journal: Gut Date: 2019-09-27 Impact factor: 23.059