Some studies have suggested that mesalamine can prevent the development of colorectal cancer in patients with ulcerative colitis.
Dr Thomas Ullman and colleagues from the USA compared rates of progression with advanced neoplasia in patient cohorts with ulcerative colitis taking low and high doses of mesalamine.
The team of doctors determined where in the process of neoplastic progression mesalamine might act.
The team identified 3 cohorts of ulcerative colitis patients from an institutional database.
The doctors assessed 311 patients with no dysplasia, 56 with indefinite dysplasia, and 26 with flat low-grade dysplasia.
|The 5-year rate for the indefinite dysplasia, at 9%|
|Clinical Gastroenterology & Hepatology|
The impact of mesalamine exposure on the subsequent development of advanced neoplasia was assessed using life-table methods.
The team found 17 of 311 patients with no dysplasia progressed to advanced neoplasia, a 5-year rate of 1%.
This rate was lower than the 5-year rate for the indefinite dysplasia, at 9%, and flat low-grade dysplasia at 45%.
Among the no dysplasia cohort, the hazard ratio for mesalamine users versus nonusers was 0.7.
The doctors noted that for each 1 g/d increase in dose, the hazard ratio was 0.9.
For patients with indefinite dysplasia, no patients on greater than 2 g/d progressed versus 14% on low-dose mesalamine.
For flat low-grade dysplasia, 63% on high dose progressed, versus 28% on low dose.
Dr Ullman’s team concluded, “In long-standing ulcerative colitis, patients with flat low-grade dysplasia have a higher rate of progression to advanced neoplasia than those with no dysplasia or indefinite dysplasia.”
“However, at none of these stages of disease did mesalamine use show definitive chemopreventive activity.”