Respondence of steroid predicts the long-term clinical and endoscopic prognosis in Cronkhite-Canada syndrome.

Background: Cronkhite-Canada syndrome (CCS) is a rare gastrointestinal polyposis syndrome characterized by hamartoma polyps and ectodermal abnormalities, with an increased risk of gastrointestinal cancers. Our previous study revealed its relapsing disease behavior and the improved long-term prognosis following the medications of steroids. However, the response of steroids varies among CCS patients, and there was no consensus about how to deal with steroid-dependent patients. This study aims to update the knowledge of long-term prognosis of CCS patients and explore the efficacy and safety of low-dose steroid as maintenance therapy.

Method: CCS patients hospitalized between 1999 and 2023 in Peking Union Medical College Hospital were enrolled. All patients were followed up through telephone interviews and outpatient visits, with clinical data and endoscopic findings sequentially collected. The Cox regression model was used to identify factors associated with clinical outcomes.

Outcome: A total of 64 eligible participants were included with a median (interquartile range) follow-up duration of 49.5 (22.75, 101.25) months. The cumulative probability of overall survival (OS) was 90.2% at 3 years, 87.7% at 5 years, 78.6% at 10 years and relapse-free survival (RFS) after steroid treatment was 76.3% at 1 year, 62.9% at 3 years, 54.4% at 5 years respectively. The poor response to steroids was identified as independent variable related to worse OS in multivariate model. In the subgroup analysis of relapsed patients, low-dose steroid treatment (prednisone ≤ 10 mg/day) for at least one year as maintenance therapy was in association with reduced risk of re-relapse (RFS: 72 (46.3, 78) vs 12 (9, 15.5) months; P = 0.02).

Conclusion: The long-term clinical outcomes of CCS are relatively favorable in patients who responded well to steroid treatment. The low-dose steroid maintenance therapy may prevent re-relapse of disease among CCS patients.