Carcinoma of the small intestine in regional enteritis: presentation of a case and review of the literature.

A case of carcinoma of the jejunum occurring in a patient with Crohn's disease of 30-years' duration is presented. Forty-seven previously reported small bowel carcinomas in Crohn's disease patients are reviewed. The incidence of small bowel carcinomas in patients with Crohn's disease has been cited as being as low as 0.08%, a figure which is still higher than the 1 in 10(9) population which would be predicted if the two diseases were independent of one another. The average age of incidence of the Crohn's carcinomas was 46.5 years while that for the de novo group was 55 years. The sexual ratios were 2.46:1 and 2:1, males to females, for the respective groups. The de novo carcinomas had a slight predilection for the duodenum at 40.7% while the latter group had a heavy predilection for the ileum at 70.8% and contained no duodenal carcinomas. The prognosis of the Crohn's group appeared to be much worse than that of the de novo group with five-year survivals of 3.7% and 20-22% respectively. Late diagnosis in the enteritis group was felt to be the major reason for this. Finally, several pathological differences between the lesions in both groups are presented.