Endoscopic surveillance was safe and effective in a prospective cohort of patients with serrated polyposis syndrome (SPS) and over 10 years of follow-ups. The procedure had a low risk of colorectal cancer (CRC) and colonoscopy-related adverse events, according to results published in Gastrointestinal Endoscopy.
SPS, the most common colonic polyposis syndrome, is associated with an increased risk of CRC. Current treatment of SPS consists of a clearing phase, during which all potentially harmful polyps are eliminated from the initial burden by endoscopy or, in severe cases, surgical resection. After this, patients undergo endoscopic surveillance every 1 to 2 years for the rest of their lives. However, the long-term safety and efficacy of surveillance and the natural disease course after initial clearance remains to be fully explored.
Researchers analyzed a single-center cohort of patients with SPS and over 10 years of follow-ups at the Amsterdam University Medical Centres in the Netherlands. In total, 142 patients (mean age at SPS diagnosis, 60.8± 9.7 years; 45.8% male) were included. Patients in the cohort underwent a median of 6 colonoscopies with a median 47 months of prospective follow-up after initial polyp clearance. Outcome measures included: the risk of CRC development; the risk of colonoscopy-related adverse events per colonoscopy and per polypectomy; and evaluating trends in polyp recurrence during multiple rounds of surveillance after the initial polyp clearance phase.
The analysis revealed long-term endoscopic surveillance is effective in detecting instances of CRC in patients with SPS. Only a single patient developed CRC while under endoscopic surveillance, corresponding to a cumulative 5-year CRC incidence of 1.0% (95% CI, 0-2.9%). A total of 447 surveillance colonoscopies and 1,308 polypectomies were performed. Only 2 adverse events occurred (1 episode of postpolypectomy bleeding, 1 postpolypectomy syndrome) corresponding to an overall adverse event risk of 0.45% (95% CI, 0%-1.6%) per colonoscopy and 0.15% (95% CI, 0%-0.6%) per polypectomy. No patients presented with perforation, corresponding to a per-colonoscopy perforation rate of 0% (95% CI, 0%-0.8%) and a per-polypectomy perforation rate of 0% (95% CI, 0%-0.28%). Lastly, during up to 9 rounds of surveillance, polyp burden fluctuated from surveillance round to surveillance round without following a discrete upward or downward pattern.
Limitations of the study included its single-center design, the enrollment of a high number of asymptomatic SPS patients, and improvement in SPS detection of participating endoscopists over the past 10 years.
The authors conclude “that polyp burden remains rather stable throughout long-term surveillance and as such life-long adherence to surveillance recommendations seems warranted. Our findings can be used to inform patients about their long-term prognosis during surveillance that will follow clearance of their initial polyp burden.”
Bleijenberg AG, IJspeert JE, Hazewinkel Y, et al. The long-term outcomes and natural disease course of serrated polyposis syndrome: over 10 years of prospective follow-up in a specialized center [published online ahead of print, 2020 Apr 30]. Gastrointest Endosc. 2020;S0016-5107(20)34268-1. doi:10.1016/j.gie.2020.04.068