Minimizing the Risk of Metachronous Adenomas of the Colorectum With Green Tea Extract -MIRACLE-

• Occurrences of colorectal adenomas or mucosal lesions [ Time Frame: 3 years ] [ Designated as safety issue: No ]
• Number of colorectal adenomas or mucosal lesions [ Time Frame: 3 years ] [ Designated as safety issue: No ]
• Size of colorectal adenomas or mucosal lesions [ Time Frame: 3 years ] [ Designated as safety issue: No ]
• Localization of colorectal adenomas or mucosal lesions [ Time Frame: 3 years ] [ Designated as safety issue: No ]
• Histological subtypes of colorectal adenomas or mucosal lesions [ Time Frame: 3 years ] [ Designated as safety issue: No ]
• Invasive growth of colorectal adenomas or mucosal lesions [ Time Frame: 3 years ] [ Designated as safety issue: No ]
• Incidence of colorectal carcinoma [ Time Frame: 3 years ] [ Designated as safety issue: No ]
• Translational research [ Time Frame: 3 years ] [ Designated as safety issue: No ]
  Genetic and biochemical biomarkers for recurrence of adenoma or development of dysplasia and carcinoma (blood samples and histological in tissue samples of the colorectal lesions)
• Toxicity and feasibility [ Time Frame: 3 years ] [ Designated as safety issue: Yes ]

This is a randomized, placebo controlled, multicentric trial to investigate the effect of diet supplementation with green tea extract containing 300mg epigallocatechin gallate (EGCG), the major polyphenol of green tea, on the recurrence of colon adenomas.

Prevention of colorectal cancer is a major health care issue because of the high incidence of this cancer. So far, pharmaceutical chemoprevention has not gained widespread acceptance due to side effects of the chemopreventive agents used. Nutraceuticals such as polyphenols from tea plants have demonstrated remarkable therapeutic and preventive effects in molecular, epidemiological and clinical trials. However, controlled trials demonstrating the efficacy of nutraceuticals fo the prevention of colorectal cancer are largely missing.

The investigators present this randomized, placebo controlled, multicentric trial to investigate the effect of diet supplementation with green tea extract containing 300mg epigallocatechin gallate (EGCG), the major polyphenol of green tea, on the recurrence of colon adenomas.

Patients who underwent polypectomy for colonic polyps will be randomized after a one month verum run-in period to receive either 150mg EGCG two times daily or placebo over the course of three years. The beneficial safety profile of decaffeinated green tea extract, the quantifiable and known active content EGCG, and the accumulating evidence on its cancer preventive potential require in our view a validation of this compound for the "nutriprevention" of colorectal adenoma. Good accessibility and low costs might render this nutraceutical a top candidate for a wider use as food supplement in colon cancer prevention.

• Colorectal Serrated Adenomas
• Colorectal Tubular Adenomas
• Colorectal Villous Adenomas
• Colorectal Tubulovillous Adenomas

• Dietary Supplement: Green tea extract of Camellia Sinensis

  Powdered decaffeinated green tea extract of Camellia Sinensis, packed in hard gelatine capsules containing either 150 mg EGCG

  • Run-in period with 150mg EGCG two times daily (p.o) for 4 weeks
  • 150mg EGCG two times daily (p.o.) over the course of three years.
  • Colonoscopy after 3 years
• Dietary Supplement: Green tea extract of Camellia Sinensis followed by placebo

  Powdered decaffeinated green tea extract of Camellia Sinensis, packed in hard gelatine capsules containing either 150 mg EGCG

  • Run-in period with 150mg EGCG two times daily (p.o.) for 4 weeks
  • Placebo two times daily (p.o.) over the course of three years
  • Colonoscopy after 3 years

• Experimental: Green tea extract
  Intervention: Dietary Supplement: Green tea extract of Camellia Sinensis
• Placebo Comparator: Placebo
  Intervention: Dietary Supplement: Green tea extract of Camellia Sinensis followed by placebo

Inclusion Criteria:

• Between 50-80 years of age
• Histologically confirmed colorectal adenomas or serrated lesions removed during colonoscopy within the last 6 months
• Good performance status (ECOG < 2) at study entrance
• Written informed consent.

Exclusion Criteria:

• History of hereditary nonpolyposis colorectal cancer (HNPCC) or familial adenomatous polyposis (FAP)
• History of colon or rectal cancer, other concomitant cancers with the exemption of basalioma or curative treated cancers without actual anticancer medication.
• Intestinal malabsorption, short bowel syndrome or surgical bowel interventions leading to malabsorption
• Liver failure (hepatitis, cirrhosis, elevation of liver enzymes ALT, AST or bilirubin to more than 2.5 fold of the reference levels)
• Inflammatory bowel disease
• Regular intake of NSAIDs (also Cox2 inhibitors) for more than 3 months per year except of low-dose aspirin (100 mg per day)
• Immunosuppressive medication
• Impaired capacity to consent or who are impaired in swallowing a pill
• Regular consumption of green tea extract as nutritional supplement (with a content of EGCG of more than 100mg per day) of longer than 6 months during the past two years
• Allergic reactions towards green tea

• University of Ulm
• Koordinierungszentrum für Klinische Studien Halle
• Deutsche Krebshilfe e.V., Bonn (Germany)