EXTRACOLONIC MANIFESTATIONS OF FAMILIAL ADENOMATOUS POLYPOSIS - DESMOID TUMORS, AND UPPER GASTROINTESTINAL ADENOMAS AND CARCINOMAS

It is well known that patients with familial adenomatous polyposis (FA P) are at considerable risk of developing extracolonic manifestations of the disease. particularly, desmoid tumours of the abdominal cavity, and duodenal adenomas and carcinomas are the most serious ones. It is estimated that some 10% of the FAP patients will develop desmoids, wh ereas 50-90% of the FAP patients will get duodenal adenomas predominan tly concentrated on or around the major papilla. Desmoid tumours and d uodenal carcinomas are major causes of death in those patients in whom a prophylactic (procto)colectomy has been performed. Desmoids are his tologically benign tumours, composed of mature fibroblasts. They usual ly grow slowly but they can become quite large and may compress or inf iltrate surrounding viscera, which might cause significant morbidity a s well as mortality. Successful treatment of these tumours is extremel y difficult as surgical therapy often requires the removal of consider able lengths of small bowel. Moreover, surgical therapy may lead to un controllable bleeding and is seldom radical. Chemotherapy with cytoxic agents seems promising but so far the data are too few for firm concl usions to be drawn. The same holds true for drug regimens which interf ere with the metabolic and hormonal metabolism of the tumour. Although various lines of evidence suggest that the adenoma-carcinoma sequence , which is generally accepted for colorectal adenomas, also applies fo r the duodenal adenomas in FAP patients, it is not clear whether we sh ould screen these patients for upper gastrointestinal adenomas or not. As these polyps are usually small, sessile, multiple and difficult to remove, the benefit of endoscopic surveillance would be the early det ection of cancer rather than eradication of the polyps. In addition, e vidence that screening and early treatment leads to improvement of the prognosis is not available. Although the role of (procto)colectomy in the treatment of large-bowel polyps is well established in FAP patien ts, the treatment of their duodenal counterparts is still open for deb ate. The risk of the development of periampullary cancer is not high e nough to warrant an aggressive prophylactic surgical approach, i.e. a Whipple's procedure, immediately after the discovery of duodenal adeno mas. The considerable morbidity and mortality rates of this procedure must be weighted against a putative benefit of screening.