Effect of indomethacin suppositories on rectal polyposis in patients with familial adenomatous polyposis

BACKGROUND: Oral sulindac is known to reduce polyps in patients with familial adenomatous polyposis (FAP). The authors speculated that rectal administration of indomethacin would be effective therapy for adenomas in the rectal remnant of FAP. METHODS: Eight patients with FAP who had been treated by total colectomy with ileorectal anastomosis were administered an indomethacin suppository (50 mg) once or twice daily during a period of 4 or 8 weeks. The number of polyps at the same site within the rectum was counted under proctoscopy prior to, at the end of, and after the treatment. In four patients, proliferative activity of the rectal mucosa was assessed by immunohistochemical staining for MIB-1. RESULTS: In six of the eight patients who initially had ten or more polyps, the number of polyps decreased to fewer than five, whereas such a decrease could not be observed in the remaining two patients. In the six patients, the number of polyps increased after indomethacin was discontinued. The proliferative activity of the rectal mucosa was higher at the end of treatment than it was prior to indomethacin administration. CONCLUSIONS: Indomethacin suppositories may be effective in the management of rectal adenomatosis in patients with FAP.