Long-term clinical outcomes and follow-up status in Japanese patients with familial adenomatous polyposis after radical surgery: a descriptive, retrospective cohort study from a single institute.

PURPOSE: Data on long-term outcomes of familial adenomatous polyposis (FAP) are unclear in Japan because a nationwide registry system is lacking. We assessed overall survival, incidence of neoplasms, fecal incontinence, and postoperative follow-up status of patients with FAP treated surgically in our hospital. METHODS: In total, 154 patients with FAP who underwent radical surgery from 1981 to 2017 in our department were available for the questionnaire. Sixty-five patients, 36 of whom were followed at our hospital, were assessed using clinical records and the questionnaire. RESULTS: The median follow-up time was 187 months (interquartile range, 93.5-296 months). The median age at surgery was 36 years (range, 12-69 years). The 5-, 10-, 15-, and 20-year overall survival rate was 100%, 98%, 95%, and 89%, respectively. All five deaths were caused by diseases other than colorectal cancer. FAP-related neoplasms comprised 23 colorectal cancers, five duodenal cancers, three gastric cancers, five thyroid cancers, two ileal pouch cancers, and nine desmoid tumors. The incidence of desmoid tumors was significantly associated with the operation date. The duration from radical surgery to neoplasm onset significantly differed by neoplasm type. Forty-five of 54 patients (excluding those who died or underwent ileostomy) developed fecal incontinence (median Wexner score of 8). Surgical procedures involving hand-sewn sutures with rectal mucosal stripping were significantly associated with fecal incontinence and the Wexner score. Fifty-eight of the 60 surviving patients underwent follow-up examinations. CONCLUSION: Overall survival was favorable. Fecal incontinence depended on the surgical procedures. Most patients continued to receive follow-up examinations. TRIAL REGISTRATION: No. 3112 by Institutional Review Board of Hyogo College of Medicine.