{
  "abstract": "Introduction Serrated epithelial change (SEC) is reported exclusively in patients with IBD colitis. Its clinical significance remains unclear, specifically whether it represents a benign regenerative lesion or is associated with an increased risk of advanced neoplasia.Methods 17 patients with UC and a history of SEC undergoing IBD surveillance colonoscopy between 10/24-09/25 were consented for repeat biopsies of the segment containing their index SEC. Patient demographics, lesion characteristics and UC details including prior/synchronous dysplasia were collected. Primary end points were development of metachronous advanced neoplasia, serrated lesions or SEC. Ethical approval was obtained for the study.Results 94% patients had extensive UC; none had PSC. Median age at detection of index SEC was 63 years (IQR 48-73), with a median IBD duration of 27 years (IQR 14-42.5). Active histologic inflammation was present in 12% patients. Median cumulative inflammatory burden was 3.5 (IQR 1-8). Multifocal SEC was observed in 17.6% patients. 80% of SEC were in the distal colon, 65% were endoscopically visible (but not within a polyp) and 95% were in areas of current or prior inflammation. ­Prior, synchronous and metachronous findings are summarised in table 1. Over a median follow-up duration of 32 months (IQR 21-36.5), with a median of 2 colonoscopies (IQR 1-3), 23.5% patients developed metachronous high-risk neoplasia in the same segment as the index SEC, after a median interval of 41.5 months (IQR 20-54). Notably, 75% of these patients had no evidence of prior or synchronous high-risk neoplasia in that segment. Recurrent SEC was identified in 29.4% patients, with 64.3% occurring in the same segment as the index SEC. 23.5% patients developed a metachronous serrated lesion in the same segment.Conclusions SEC is associated with high rates of metachronous advanced neoplasia. Further comparative clinical and molecular studies are necessary to better define its clinical significance.Abstract P212 Table 1Prior, synchronous and metachronous resultsParameterResult (n=17)Prior findingsPrior high-risk neoplasia in same segment35%Prior high-risk neoplasia in dif. segment11.8%Prior serrated lesion in same segment29.4%(2HPs, 2 SSL, 1 SSL-D)Synchronous findingsSynchronous high-risk neoplasia in same segment23.5%Synchronous high-risk neoplasia in dif. segment17.6%Synchronous SSL in same segment5.9%Metachronous findingsMetachronous high risk-neoplasia in same segment23.5% (2 adenocarcinomas, 1 LGD, 1 high-risk TALGD)Median interval between index SEC and metachronous high-risk neoplasia41.5 months (IQR 20-54)Metachronous serrated lesions in same segment23.5% (1 HP, 5 SSLs, 1 SSL-D)Recurrent SEC29.4%Median interval between index and metachronous SEC15 months (IQR 9-16)Recurrent SEC in same region as index64.3%Recurrent SEC invisible28.6%Recurrent SEC in distal colon85.7%",
  "authors": [
    {
      "affiliations": [
        "St. Mark’s National Bowel Hospital, St. Mark’s Academic Institute, London, United Kingdom"
      ],
      "name": "Sara Renshaw"
    },
    {
      "affiliations": [
        "St. Mark’s National Bowel Hospital, Department of Gastroenterology, London, United Kingdom"
      ],
      "name": "Andrew Latchford"
    },
    {
      "affiliations": [
        "St. Mark’s National Bowel Hospital, Department of Gastroenterology, London, United Kingdom"
      ],
      "name": "Siwan Thomas-Gibson"
    },
    {
      "affiliations": [
        "St. Mark’s National Bowel Hospital, St. Mark’s Academic Institute, London, United Kingdom",
        "St. Mark’s National Bowel Hospital, Department of Gastroenterology, London, United Kingdom"
      ],
      "name": "Ana Wilson"
    }
  ],
  "title": "P212 Exploring the clinical significance of serrated epithelial change: a prospective analysis of patients with UC",
  "uid": "fc37e1b0-a7c4-54a3-8144-b25381b71761"
}