Incidence of colorectal lesions in first degree relatives of patients with serrated polyposis syndrome.

Serrated polyposis syndrome (SPS) is characterized by the presence of multiple colorectal hyperplastic polyps (HPs) and sessile serrated adenomas (SSAs) and is associated with an increased colorectal cancer (CRC) risk. First degree relatives (FDRs) of SPS patients are also believed to have an increased risk for both CRC and SPS, but only scarce retrospective data are available. Prospective evaluation of the magnitude of these risks in FDRs is necessary to determine whether screening colonoscopies are indicated in these persons. The aim of this study is a prospective assessment of the prevalence, distribution and type of neoplasia in FDRs of SPS patients.



We will invite all FDRs > 35 years of age or 5 yrs younger than the index case for a screening colonoscopy. FDRs who had already undergone a colonoscopy in the last 3 years and FDRs with a medical history of CRC will be excluded. All responders undergo a standard white light colonoscopy, either in an academic or local hospital. All polyps are removed or biopsied if very small. Primary outcomes are the incidence of CRC, adenoma detection rate (ADR) and presence of multiple (>2) proximal serrated polyps (HPs or SSAs). In order to assess whether screening colonoscopies are justified in FDRs of SPS patients, we compare the ADR in this cohort with previously reported ADRs in subjects of the same age fulfilling the criteria of familial CRC.

To prospectively study the incidence of polyps and CRC in first degree relatives of patients with serrated polyposis syndrome.

Inclusion: December 2008 - march 2012.

Data analysis: March 2012.

All eligble FDRs are invited to undergo a standard white light screening colonoscopy.