Features of Duodenal Cancer in Patients With Familial Adenomatous Polyposis

Abstract

Most patients with familial adenomatous polyposis (FAP) develop duodenal adenomas; duodenal cancer is a major cause of mortality in this patient group. We reviewed cases of duodenal cancer in patients with FAP to identify factors that determine long-term cancer risk. Twenty FAP patients (12 male) were identified from a registry database search. Data from registry and medical notes and endoscopic and histopathologic reports were evaluated. Of the cancers that developed in these patients, 11 were ampullary and 9 were duodenal. The median age at cancer diagnosis was 53 years. Seventeen patients died (median age at death, 57 y; median survival from diagnosis, 11 mo); the cause of death was metastatic or duodenal/ampullary cancer in 14 patients. Fifteen patients presented symptomatically (including 3 interval cancers while on surveillance). Two were diagnosed at surveillance and 3 were diagnosed during surgery performed for endoscopic features of advanced benign disease. Duodenal cancers were associated with a significantly lower mean colonic polyp count than ampullary cancers (496 +/- 282 vs 1322 +/- 735; P = .025); there appeared to be familial clustering of this cancer. When endoscopic data were available (n = 11 of 20), all ampullary cancers arose from ampullas greater than 1 cm. The Spigelman stage did not predict risk of ampullary cancer but did predict duodenal cancer (median stage 2 vs stage 4 for duodenal cancer). Once cancer arises in patients with FAP, prognosis is poor, so cancer prevention should be the main goal. Surveillance intervals should reflect both Spigelman staging and ampullary disease.