Figure 2: A pilot study demonstrating the chemopreventive effect of green tea extract (GTE) on metachronous adenomas after endoscopic polypectomy. (A) Study design. The study included 136 participants who underwent endoscopic resection of one or more colorectal adenomas. Twelve months later, the participants received another total colonoscopy to confirm the absence of remaining endoscopically-detectable adenoma. The participants were then randomized into two groups while administering a daily green tea drinking; the GTE group (71 patients) was given three GTE tablets a day for 12 months and the control group (65 patients) received no supplement. After 12 months of GTE supplementation, a follow-up (end-point) colonoscopy was performed in 125 patients (60 in the GTE group and 65 in the control group) to check the presence of new adenomas. (B) Effects of the GTE supplementation on the incidence and the size of metachronous colorectal adenomas at the end-point colonoscopy. The incidence of adenomas was 15% (9 of 60) in the GTE group and 31% (20 of 65) in the control group. The size of relapsed adenomas was significantly smaller in the GTE group than that of the control group.