Antioxidant Supplement and Reduction of Metachronous Adenomas of the Large Bowel: a Double Blind Randomized Trial

Phase 3

Terminated

• Conditions: Colorectal Adenomas
• Interventions: Drug: antioxidants; Drug: placebo

• Registration Number: NCT01437826
• Lead Sponsor: IRCCS Azienda Ospedaliera Universitaria San Martino - IST Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy

Brief Summary

The trial was aimed at evaluating the efficacy of a multiagent antioxidant compound (vitamin A, C, E, selenium and zinc) in reducing the incidence of metachronous adenomas of the large bowel after endoscopic polypectomy. This is a randomized study: a 50% reduction in the incidence of metachronous adenomas was expected in patients allocated to the "active" compound (intervention) arm as compared to those assigned to a placebo.

Detailed Description

Adenomatous polyps (or adenoma) are benign lesions of the large bowel that are frequent in people aged 60 or more: about one in four of them has at least one adenoma. In time, adenoma could progress to cancer. Even though only a small rate of adenomas will develop into cancer almost 70-80% of colorectal cancer origin from an adenoma and colorectal cancer is one of the most frequent malignant tumors in the western world. Several epidemiological studies showed that subjects who had low intake and/or low blood levels of selenium were at increased risk of developing colorectal cancer.

Study Timeline

• Study Start: 1988-03
• Primary Completion: 1996-06
• Study Completion: 1996-06
• Status Verified: 2011-09
• Study First Submitted: 2011-09-14
• Study First Submitted QC: 2011-09-19
• Last Update Submitted: 2011-09-19
• Study First Posted: 2011-09-21
• Last Update Posted: 2011-09-21

Recruitment & Eligibility

• Status: TERMINATED
• Sex: All
• Target Recruitment: 411

Inclusion Criteria

• age 25-75 years
• at least one histologically confirmed adenoma endoscopically removed from the large bowel resulting in a polyp-free colon-rectum (clean colon).

Exclusion Criteria

• polypectomy performed more than 6 months before enrolment in the trial
• history of Familial Adenomatous Polyposis
• inflammatory bowel disease
• adenoma with invasive carcinoma
• ten or more adenomas
• large sessile adenoma (3 cm or more
• colorectal resection
• invasive cancer at any site
• life-threatening and/or chronic heart, liver or kidney diseases
• current use of vitamin or calcium supplements
• mental disability

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
antioxidants	antioxidants	tablets composed of 200 mcg selenium \[as l-selenomethionine\], 30 mg zinc, 2 mg vitamin A \[retinol\], 180 mg vitamin C \[ascorbic acid\] and 30 mg vitamin E \[D-α-tocopherol acetate\]
Sugar pill	placebo	placebo had an identical appearance as intervention

Primary Outcome Measures

Name	Time	Method
occurrence of metachronous adenomas or cancer detected during endoscopic follow up examinations	five years

Trial Locations

Locations (1)

IRCCS Azienda Ospedale Università San Martino - IST Istituto Nazionale per la Ricerca sul Cancro; 🇮🇹 Genova, Italy