The prevalence of small intestinal polyps in patients with familial adenomatous polyposis: a prospective capsule endoscopy study

Familial adenomatous polyposis (FAP) is a genetic disorder in which multiple colorectal polyps and cancers develop. However, the prevalence of small intestinal tumors in patients with FAP remains unclear. We elucidated the prevalence of polyps in the small intestine and duodenum using capsule endoscopy (CE). Patients with FAP receiving a periodic screening colonoscopy at Kyoundo Hospital were encouraged to participate in the study. All study participants underwent esophagogastroduodenoscopy (EGD) within 2 weeks before CE. Outcome measurements were the prevalence of duodenal polyps (DP) and small intestinal polyp (SIP), detectability of the ampulla of Vater, and concordance of the duodenal findings between CE and EGD. Twenty-three patients (mean age, 47 years; 15 males) were enrolled in the study. CE showed DPs in 11 patients (52 %) and SIPs in nine patients (43 %). The mean numbers of DPs and SIPs was 11.5 ± 6.2 and 11.9 ± 10.9, respectively. SIPs were more often detected in patients with DPs versus those without (62 vs. 13 %, P = 0.07). The ampulla of Vater was observed by CE in four patients (21 %). EGD showed DPs in 13 patients (62 %). EGD missed DPs in two of 11 patients with DPs detected by CE. EGD found DPs in four of 10 patients without DPs using CE. The kappa index was 0.422. Patients with FAP have a high prevalence of polyps in the small intestine. Although the clinical significance of small intestinal polyps remains unclear, patients with FAP seem to be good candidates for CE.