Colorectal cancer (CRC) is a common malignancy of the digestive tract, which constitutes a major public health burden. Almost 90% of CRC cases progress from precursor adenomatous polyps through adenoma-carcinoma sequence. Endoscopic detection and removal of colorectal adenoma (CRA) could reduce the incidence and mortality risk of CRC, but the recurrence rate is still high. Therefore, chemoprevention is quite important, not only solve the urgent public health problem, but also be cost-effective.

In 2020, the investigators published a multicenter, randomized, double-blind, placebo-controlled clinical study (NCT02226185) in the Lancet Gastroenterology & Hepatology. The result concluded that oral BBR for 2 years significantly reduced recurrence after endoscopic removal of CRA (RR 0.77, 95%CI 0.66-0.91; p=0.001). BBR also has a significant preventive effect on all polypoid lesions, including adenomas and serrated lesions (adjusted RR 0.78, 95%CI 0.66-0.91; p=0.002) . Does BBR still have a long-term protective effect on the recurrence of CRA after discontinuation? That's what the investigators concerned.

The present study is performed to observe and compare retrospectively the recurrence rate of CRAs in patients of the original BBR RCT study (NCT02226185) within 6 years after discontinuation of medication, including the overall recurrence rate of traditional adenomas within the first year, 1-3 years, 3-6 years, and the entire follow-up period of 6 years. The aim is to evaluate the long-term efficacy of BBR in preventing recurrence and carcinogenesis after endoscopic resection of CRAs.

Inclusion Criteria: participants who completed the previous berberine intervention study (NCT02226185) Exclusion Criteria: no

We included 895 participants who completed the previous berberine intervention study (NCT02226185), including 432 participants in the BBR group and 463 participants in the placebo group.

All included IPD