Progression of duodenal adenomatosis in familial adenomatous polyposis: due to ageing of subjects and advances in technology.

Familial adenomatous polyposis patients are at risk of duodenal cancer. Surveillance is indicated and the extent of duodenal polyposis is quantified by the Spigelman staging system. We noticed an impressive increase in high Spigelman stages over the years and therefore decided to investigate whether this increase might be due to the time-lapse since the inception of surveillance or related to improvements in endoscopic imaging and/or changes in dysplasia-reporting. Patients who were investigated by the same endoscopist since 1980 in at least 2 different episodes of technical improvements were eligible. The period 1980-2009 was divided into 4 episodes using the following landmarks: replacement of fibre-endoscopes by video-endoscopes in 1987, change in processors in 1995, change in image resolution in 2000, and change in dysplasia-reporting in 2006. An increase in Spigelman stages from low stages (0-II 100%) to high stages (III 28.1%, IV 43.8%) was seen (median follow-up: 19.5 years). In patients who progressed, a median of 4 years elapsed before progression by one stage occurred and 7 years to progress by two stages. In a mixed-model analysis, both time-lapse and technical improvements were determinant factors for duodenal disease progression. When both factors were introduced in the model, the time-lapse as well as the change in image resolution and dysplasia-ranking contributed consistently in increasing Spigelman scores and stages. The impressive increase in severity of duodenal polyposis is determined by time-lapse, technological advances and change in dysplasia-reporting. These results might call for a revised Spigelman classification.