Clinical Trial: Green Tea Extracts for the Prevention of Colorectal Adenomas and Colorectal Cancer

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Green Tea Extracts for the Prevention of Colorectal Adenomas and Colorectal Cancer

Brief Summary: Experimental studies have shown the chemopreventive properties of green tea extract (GTE) on colorectal cancer. And colorectal adenomas are precursors to colorectal cancers. The aim of this study is to determine the preventive effect of GTE supplements on metachronous colorectal adenomas by giving GTE tablets of which are equivalent of 9 cup-of-green tea per day (0.9 g/day GTE, 0.6 g/day Epigallocatechin gallate (EGCG).

Detailed Summary: The subjects who had undergone complete removal of colorectal adenomas by endoscopic polypectomy have been enrolled since June 2010. They were then randomized into two groups as follows: supplementation group (0.9 g GTE per day for 12 months) or control group without GTE supplementation. Follow-up colonoscopy was conducted in 12 months. A structured 72-h recall at baseline and the 1-year follow-up was used to assess dietary factors, and to evaluate rectal mucosal proliferation index (RMPI) using known proliferation markers (Ki-67/PCNA), at least 2 random biopsies of rectal mucosa were taken. A sample size of 176 patients (88 per each group) was calculated to give the study 80% power to detect a difference, assuming a two-sided significance test at the 0.05 level.
Sponsor: Seoul National University Hospital

Current Primary Outcome: Recurrence/Number/Size of metachronous colorectal adenoma(s) [ Time Frame: 1 year ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Recurrence/Number/Size of metachronous colorectal polyp(s) including hyperplastic polyp(s) [ Time Frame: 1 year ]
  • Change of lipid profiles after green tea extract (GTE) supplementation [ Time Frame: 1 year ]
  • Change of body weight, BMI and waist circumference [ Time Frame: 1 year ]
  • Adverse effect(s) of GTE supplementation [ Time Frame: every 1-3 months till the end of study protocol (12 months) ]


Original Secondary Outcome: Same as current

Information By: Seoul National University Hospital

Dates:
Date Received: December 17, 2014
Date Started: August 2010
Date Completion:
Last Updated: October 26, 2015
Last Verified: October 2015