Duodenal surveillance improves the prognosis after duodenal cancer in familial adenomatous polyposis

Aim Duodenal adenomatosis in familial adenomatous polyposis results in a cancer risk that increases with age. Endoscopic surveillance has been recommended, but the effect has not yet been documented. The aim of this study was to present the results of long‐term duodenal surveillance and to evaluate the risk of cancer development. Method Follow up of patients in a previous study with gastroduodenoscopy in 1990–2010. Statistical analysis included the χ2 test, actuarial method and Kaplan–Meier analysis. Results Among 304 patients, 261 (86%) had more than one endoscopy. The median follow up was 14 (interquartile range, 9–17) years. The cumulative lifetime risk of duodenal adenomatosis was 88% (95% CI, 84–93), and of Spigelman stage IV was 35% (95% CI, 25–45). The Spigelman stage improved in 32 (12%) patients, remained unchanged in 88 (34%) and worsened in 116 (44%). Twenty (7%) patients had duodenal cancer at a median age of 56 (range, 44–82) years. The cumulative cancer incidence was 18% at 75 years of age (95% CI, 8–28) and increased with increasing Spigelman stage at the index endoscopy to 33% in Spigelman stage IV (P