Surgery is the definitive treatment in familial adenomatous polyposis coli (FAP). Proctocolectomy with ileal pouch anal anastomosis is recommended for the majority of FAP patients. Only in patients with attenuated FAP, is a colectomy with ileorectal anastomosis (IRA) accepted, although the risk for rectum carcinoma remains increased. Sulindac, a chemoprophylactic agent, regresses colorectal adenomas in patients with FAP. Under systemic Sulindac-therapy, three carcinomas in the rectum after colectomy with IRA have been described. We report the first known case of rectum carcinoma in a patient with FAP, 51 months after IRA and local Sulindac therapy.