Proximal colon cancer and serrated adenomas - hunting the missing 10%.

There is a 10% shortfall in the number of proximal colorectal cancer cases detected by the UK Bowel Cancer Screening Programme and the actual number of UK-registered proximal colorectal cancers. Sessile serrated adenomas/polyps (SSA/P) are common premalignant lesions in the proximal colon and are notoriously difficult to spot endoscopically. Missed or dismissed SSA/Ps might contribute to this UK proximal colon cancer detection disparity. In Oxfordshire, a service evaluation audit and histological review has shown a linear increase in the detection rate of these lesions over the past 4 years. This is the result of increased endoscopist and pathologist awareness of these lesions and improved interdisciplinary communication. This is the result of increased endoscopist and pathologist awareness of these lesions, together with improved interdisciplinary communication, and we predict that this will lead to a comparable detection increase nationwide. Ongoing surveillance of an increasing number of these premalignant lesions could become a significant endoscopic resource requirement once UK guidelines on serrated lesion follow up are established.