Serrated polyposis syndrome is accompanied by an increased risk of colorectal cancer.
Patients fulfilling the clinical criteria, as defined by the WHO, have a wide variation in colorectal cancer risk.
Dr Evelien Dekker and colleagues from the Netherlands assessed the risk factors for colorectal cancer in a large cohort of patients with serrated polyposis syndrome, and evaluated the risk of colorectal cancer during surveillance.
In this retrospective cohort analysis, all patients with serrated polyposis syndrome from 7 centers in the Netherlands, and 2 in the UK were enrolled.
WHO criteria were used to diagnose serrated polyps.
The team excluded patients who only fulfilled WHO criterion-2, with IBD and/or a known hereditary colorectal cancer syndrome.
| ≥1 serrated polyp with dysplasia was associated with colorectal cancer|
In total, 434 patients with serrated polyps were included for analysis, 29% were diagnosed with colorectal cancer.
The researchers found that in a per-patient analysis ≥1 serrated polyp with dysplasia, ≥1 advanced adenoma, and the fulfilment of both WHO criteria 1 and 3 were associated with colorectal cancer, while a history of smoking was inversely associated with colorectal cancer.
Overall, the team noted that 260 patients underwent surveillance after clearing of all relevant lesions, during which 2 patients were diagnosed with colorectal cancer, corresponding to 2 events per 1000 person-years surveillance.
Dr Dekker's team concludes, "The presence of serrated polyps containing dysplasia, advanced adenomas and/or combined WHO criteria 1 and 3 phenotype is associated with colorectal cancer in patients with serrated polyposis syndrome."
"Patients with a history of smoking show a lower risk of colorectal cancer, possibly due to a different pathogenesis of disease."
"The risk of developing colorectal cancer during surveillance is lower than previously reported in literature, which may reflect a more mature multicentre cohort with less selection bias."