Personalized Surveillance Protocol for Serrated Polyposis Syndrome

Serrated polyposis syndrome (SPS) is a condition characterized by the presence of multiple serrated polyps (SPs) spread throughout the colorectum and is associated with an increased risk of colorectal cancer (CRC). SPS is defined by the World Health Organization (WHO) as the presence of at least 5 SPs proximal to the sigmoid colon, of which 2 ≥10 mm in size (WHO criterion 1), the presence of at least 1 SP proximal to the sigmoid and a first degree relative with SPS (WHO criterion 2), or more than 20 SPs spread throughout the colon (WHO-criterion-3). In practice only WHO 1 and WHO 3 criteria are used. The condition seems rather common and more prevalent than other polyposis syndromes such as familial adenomatous polyposis (FAP) (1:13.000). Several retrospective studies have shown that patients with SPS have an increased risk of developing CRC during endoscopic surveillance. Close endoscopic surveillance to prevent malignant progression of polyps has therefore been advised by several expert groups. However, due to a shortage of prospective data the optimal treatment and surveillance approach is largely unknown. The current study aims to prospectively evaluate the effectiveness and feasibility of a personalized surveillance protocol for patients with SPS to prevent CRC that is being used in several Dutch and Spanish hospitals. Furthermore, the polyp burden, colonoscopy complication risk and rate of conversion from endoscopic surveillance to colorectal surgery will be examined. For this purpose, all eligible SPS patients are prospectively enrolled 2013 onwards, and surveyed according to the study protocol. Based on the amount and characteristics of the polyps encountered during surveillance colonoscopy, the next colonoscopy will be scheduled after either 1 year or 2 years. Patients will undergo surveillance after 1 year in case of: * Advanced adenoma (≥ 10 mm and/or high-grade dysplasia and/or 25% villous component) * Serrated polyp ≥ 10mm and/or SP containing dysplasia * Cumulative ≥5 sessile serrated polyps (SSPs) (irrespective of size), adenomas (irrespective of size) and/or hyperplastic polyps (HPs) ≥5mm * Surgery needed during previous (clearing or surveillance) endoscopy Patients will undergo surveillance after 2 years in case none of above is reached

Sex

All

Minimum age

18 Years

Inclusion Criteria:

* Patients with SPS WHO 1 criterion (cumulative ≥ 5 histologically diagnosed SPs proximal to the sigmoid colon, of which 2 ≥ 10mm in diameter) and/or WHO 3 criterion (cumulative ≥ 20 SPs spread throughout the colon, at least 3 of the SPs will have to be situated proximal to the sigmoid colon).
* Age 18 years or older

Exclusion Criteria:

* \- Germline mutation for hereditary colorectal cancer syndrome (e.g. familial adenomatous polyposis, Lynch syndrome. Not including heterozygous MUTYH mutation)
* Inflammatory bowel disease
* Proctocolectomy
* History of radiotherapy in abdominal region