Excluded rectums for Crohn's disease: what is the risk of dysplasia?

Objectives - An excluded rectum may be at risk of carcinoma in the course o f Crohn's disease. Surveillance of patients requires detection of dysplasia . The aim of our study was to determine the frequency of dysplasia from sec ondary proctectomy specimens in active rectal Crohn's disease. Methods-Twenty three patients (13 women and 10 men, median age 38 years) we re studied. The median duration of rectal exclusion was four years. Detecti on of dysplasia relied upon histopathology. Immunohistochemistry with MIB-I (Ki-67) and anti-p53 (clone DO7) antibodies was performed as well. Results-Frequency of dysplasia was 30%, This was low grade dysplasia, focal ly observed in proctectomy specimens. MIB-1 was positive on 46% of dysplast ic cells. There was no expression of p53 protein. Conclusions - These results must be taken into account for decision of seco ndary proctectomy, in patients having an excluded rectum for Crohn's diseas e, when ileorectal anastomosis is not possible. Rectal endoscopic surveilla nce is advisable with multiple biopsies according to focal distribution of dysplasia.