How often does the patient repeat screening colonoscopy? A study for personalized recommendation of screening colonoscopy interval.

Abstract

527 Background: Colorectal cancer (CRC) is the third most common cancer and the second most frequent cause of cancer death of female and fourth most of male in South Korea. Most CRCs develop through the adenoma–carcinoma sequence, which allows for screening and prevention of CRCs by screening colonoscopic examination and polypectomy. However, there have been limited data on personalized optimal time interval of next surveillance colonoscopic examination. The aim of our study is to recommend personalized interval by analysis of various clinical factors obtained by health care examination. Methods: We enrolled the patients who underwent two times more voluntary, complete screening colonoscopy at health care unit of Korea University Medical Center Anam Hospital from July 1, 2004 to July 31, 2010. The clustering analysis using the partitioning around medoids algorithm and Hierarchial cluster were conducted including the 32 clinical, geographic and laboratory data. For each cluster, we then performed survival analysis that provides the probability of having polyps according to the number of days until next colonoscopy. Results: Totally 8,332 patients underwent screening colonoscopy, among them 625 patients performed repeat colonoscopy exam. 625 patients divided four clusters by clustering analysis. Adenoma detection at first screening colonoscopy was the most potent risk factor of develop of adenoma at next screening. Male gender, triglyceride (>134 mg/dL), and age (>56 years old) were significant factor for decision of the personalized interval of next screening colonoscopy. For example, male patient, who had adenoma at fist screening, the predicted risk of adenoma is 50% after 25 months. Conclusions: Our study can provide personalized time interval of next screening colonoscopy according to patients’ individual clinical data. Further study are necessary for validation our results.