Intestinal and extra-intestinal cancer in Crohn's disease: follow-up of a population-based cohort in Copenhagen County, Denmark.
OBJECTIVE
To determine the long-term risk of intestinal and extra-intestinal malignancies in Crohn's disease patients in Copenhagen County, Denmark.


METHODS
In Copenhagen County, a strictly population-based cohort of 374 patients with Crohn's disease diagnosed between 1962 and 1987 was followed until 1997 in order to determine the long-term risk of intestinal and extra-intestinal malignancies. Information on cancer occurrence was provided by the Danish National Cancer Registry and confirmed by the examination of hospital files. The observed number of cases was compared with the expected number, calculated from individually computed person-years at risk and 1995 cancer incidence rates for the background population.


RESULTS
The risk of small bowel adenocarcinoma was significantly increased, independent of age and gender (standardized morbidity ratio, 66.7; 95% confidence interval, 18.1-170.7). The risk of colorectal cancer was not increased, either in the total group of patients or in patients with colonic Crohn's disease exclusively (standardized morbidity ratio, 1.64; 95% confidence interval, 0.20-5.92). Extra-intestinal cancer did not occur more frequently than expected.


CONCLUSIONS
This population-based study of patients with Crohn's disease revealed no increase in colorectal cancer risk, possibly due to maintenance treatment with 5-aminosalicylic acid preparations and surgery in treatment failure. In contrast, the risk of small bowel cancer was increased more than 60-fold, but the numbers were small. The risk of extra-intestinal cancer was not increased and no lymphomas were observed.
Jess
T
T
Department of Medical Gastroenterology, Herlev Hospital, University of Copenhagen, Denmark. tinejess@dadlnet.dk
Winther
K V
KV
Munkholm
P
P
Langholz
E
E
Binder
V
V
D000230:Adenocarcinoma / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D001379:Azathioprine / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology*; D003424:Crohn Disease / Q000150:complications* / Q000453:epidemiology; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D005765:Gastrointestinal Agents / Q000627:therapeutic use; D006801:Humans; D007078:Ileal Neoplasms / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology*; D007223:Infant; D007580:Jejunal Neoplasms / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D011239:Prednisolone / Q000627:therapeutic use; D012307:Risk Factors; D012460:Sulfasalazine / Q000627:therapeutic use; D016896:Treatment Outcome
D000964:Antimetabolites, Antineoplastic; D018931:Antineoplastic Agents, Hormonal; D005765:Gastrointestinal Agents; D012460:Sulfasalazine; D011239:Prednisolone; D001379:Azathioprine