Cancer in Crohn's Disease Patients Treated with Infliximab: A Long-term Multicenter Matched Pair Study

Background: The long-term risk of neoplasia in Crohn's disease (CD) patients treated with infliximab is undefined. The aim was to assess, in a multicenter, matched-pair study, whether infliximab use in CD is associated with an increased frequency of neoplasia in the long term. Methods: A multicenter, long-term, matched-pair study was conducted in 12 referral inflammatory bowel disease (IBD) centers. An initial cohort of 808 CD patients, including 404 infliximab-treated (CD-IFX) and 404 matched CD controls never treated with infliximab (CD-C) studied from 1999 to 2004, was followed up for an additional 4 years (2004-2008). Cases and controls were matched for: sex, age (+/- 5 years), CD site, follow-up (+/- 5 years), immunosuppressant use, and CD duration (+/- 5 years). From 1999 to 2008 the frequency and characteristics of neoplasia were compared between CD-IFX and CD-C. Results: In 2008, 591 patients (304 CD-IFX, 287 CD-C) were in follow-up. Matched couples included 442 patients: 221 CD-IFX and 221 CD-C (median follow-up, months: 72, range 48-114 versus 75, range 44-114). From 1999 to 2008 the frequency of neoplasia among the 591 patients did not differ between CD-IFX (12/304; 3.94%) and CD-C (12/287; 4.19%; P = 0.95). A comparable frequency of neoplasia was also observed between the 221 matched couples (CD-IFX: 8/221; 3.61% versus CD-C: 9/221; 4.07%; P = 1). No specific histotype of cancer appeared associated with infliximab use. Conclusions: The frequency of neoplasia was comparable in an adult population of CD patients treated or not with infliximab, matched for clinical variables and followed up for a median of 6 years.