Papillary thyroid cancer and inflammatory bowel disease:Is there a relationship?

AIM:To formally study age of diagnosis of papillary thyroid cancer(PTC) in inflammatory bowel disease(IBD) patients and evaluate the prevalence of PTC in IBD patients compared to a control population.pothesis that patients with IBD are more likely to be diagnosed with PTC than a control population.A retrospective cohort analysis was performed using the University of Pennsylvania Health System’s electronic database.Outpatients from 1998-2009 were included in the search,and patients in the cohort were selected based on ICD-9 codes.Inclusion criteria included the diagnosis of Crohn’s disease(CD) or ulcerative colitis(UC) and the concurrent diagnosis of thyroid cancer in comparison to a control population.Using these methods 912 patients with CD and 1774 with UC were compared to 1638 diverticulitis and 19 447 asthma controls.Statistics were performed using corrected chisquare analysis.The primary outcome for this study was the diagnosis of PTC.Approval to conduct this study was obtained by the Institutional Review Board at the University of Pennsylvania.RESULTS:The mean age was 47.5 years(range:18-102 years) and 66% patients were female.An analysis of variance model was used to compare the age of PTC diagnosis between the CD,UC,asthma and diverticulitis groups,and a statistically significant difference in age at PTC diagnosis was noted across all groups(F = 6.35,df = 3,P = 0.0006).The age of PTC diagnosis in CD patients was statistically significantly lower than UC,asthma,and diverticulitis patients(average PTC diagnosis age for CD 25,UC 49,asthma 45,diverticulitis 63).After covarying for sex and age in 2009,the difference in age at PTC diagnosis remained statistically significant(F = 4.13,df = 3,P = 0.0089).A total of 86 patients were diagnosed with PTC.Nine patients(0.5%) with UC were diagnosed with PTC.Patients with UC were not shown to be more likely to develop PTC [odds ratio(OR):1.544,95%CI 0.767-3.108] compared to asthma controls.Four patients(0.4%) with CD were diagnosed with PTC.Patients with CD were no