Endoscopic Characteristics of Duodenal and Ampullary Lesions (DUO/AMP-LST)

• Significant differences in molecular abnormalities. [ Time Frame: Specimens will be stored and used for up to 15 years ] [ Designated as safety issue: No ]
  The aim of this project is to look for statistically significant differences in molecular abnormalities from the three known genetic pathways, between the two different morphological types, granular and non-granular, to potentially demonstrate that these different polyps form via different genetic pathways.
  
  

Laterally spreading tumours (LSTs), are polyps that have a lateral extension along the duodenal wall with minimal vertical growth. It has become evident over the last few years that rather than being a single entity requiring an accumulation of mutations, Duodenal and ampullary cancer is in fact a heterogenous disease forming via multiple distinct genetic pathways. It is therefore hypothesised that different polyp types have different genetic abnormalities, and potentially form via distinct genetic pathways, although this theory has not been widely examined.

This knowledge would be important in furthering our understanding of the development of cancer. There is accumulating evidence that genetic abnormalities may be a better predictor of cancer behaviour than histological grade. Additionally, guidelines for endoscopy surveillance are currently a one size fits all approach that do not reflect the genetic heterogeneity of the disease and the knowledge that only 5% of polyps progress to cancer. Genetic studies may assess future cancer risk to a person in polyps once removed and plan surveillance endoscopy frequency.