The Long-Term Clinical and Endoscopic Outcomes of Cronkhite–Canada Syndrome

The prognosis of Cronkhite–Canada syndrome (CCS) is considered poor. Despite the recent therapeutic improvements, the survival outcomes and prognostic factors have been less studied. This study aimed to investigate the long-term clinical and endoscopic outcomes of CCS. METHODS: Thirty-one patients diagnosed since 1999 and followed up for over 6 months were included. Data regarding survival outcomes, clinical symptoms, endoscopic findings, and treatment were collected and analyzed. R (version 3.6.1) was used to perform the survival analyses. RESULTS: The median (interquartile range) follow-up time was 42.5 (19.5–85.8) months. The 5-year overall survival (OS) was 87.4%. The maximum gastric polyp size over 2 cm was associated with worse OS (Hazard ratio [HR]: 18, 95% confidence interval [CI]: 1.6–210, P = 0.021). The 3-year relapse-free survival (RFS) after corticosteroid treatment was 66.8%. Age older than 60 years (HR: 7.0, 95% CI: 1.5–33.0, P = 0.015) and maximum gastric polyp size over 2 cm (HR: 6.0, 95% CI: 1.6–23.0, P = 0.009) were associated with worse RFS. Twenty-three patients received follow-up endoscopic examinations, with a median (interquartile range) follow-up time of 29.0 (14.0–53.5) months. Eight (34.8%) and 12 (52.2%) patients achieved complete remission under gastroscopy and colonoscopy, respectively. Colonic lesions showed a tendency of earlier responses compared with gastric lesions (25.0 [11.3–39.8] months vs 31.0 [21.0–39.8] months). DISCUSSION: Patients with CCS usually responded well to glucocorticoids with a fairly good 5-year survival rate. Large gastric polyp was associated with worse OS and RFS, whereas age older than 60 years was another predictor for worse RFS. Diffuse gastrointestinal lesions partly or completely resolved after treatment, and colonic lesions showed a better response than gastric lesions.