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Polyp Prevention Trial

This study has been completed.
Information provided by (Responsible Party):
National Institutes of Health Clinical Center (CC) ( National Cancer Institute (NCI) ) Identifier:
First received: June 19, 2006
Last updated: May 12, 2017
Last verified: March 17, 2017
The primary objective of the Poly Prevention Trial (PPT) is to determine whether a low fat, high fiber, high vegetable and fruit eating plan will decrease the recurrence of adenomatous polyps of the large bowel. Secondary objectives of the PPT include 1) evaluating the effectiveness of the intervention program with respect to participant achievement of dietary goals; 2) examining the relation of dietary change and biochemical markers in blood; and 3) assessing the impact of the intervention on quality of life indicators.

Condition Intervention Phase
Other: low fat, high fiber, high fruit and vegetable eating plan
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: No masking
Primary Purpose: Prevention
Official Title: Polyp Prevention Trial

Resource links provided by NLM:

Further study details as provided by National Institutes of Health Clinical Center (CC):

Primary Outcome Measures:
  • Incidence of polyps in the colon [ Time Frame: Yearly for 4 years ]

Estimated Enrollment: 2440
Study Start Date: June 19, 1991
Study Completion Date: April 14, 2011
Arms Assigned Interventions
Experimental: 1
low fat, high fiber, high fruit and vegetable eating plan
Other: low fat, high fiber, high fruit and vegetable eating plan
Participants were randomized to a low fat, high fiber, high fruit and vegetable (intervention arm) or their usual diet (control arm)
No Intervention: 2
Usual Diet

  Show Detailed Description


Ages Eligible for Study:   35 Years to 99 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Men and women who at the time of randomization are 35 years of age or older and have had removed within 6 months of randomization one or more adenomatous polyps confirmed histologically by the Clinical Center trial pathologist.


Persons with any of the following characteristics are ineligible for the study:

Carcinoma in any polyp removed at baseline endoscopy. High grade dysplasia is not considered carcinoma for purposes of study eligibility.

Failure to examine the cecum during baseline colonoscopy.

Incomplete removal of polyps at baseline colonoscopy.

Surgical removal of polyps.

Familial polyposis or other polyposis syndromes.

Adenomatous polyp discovered before the age of 35.

History of large bowel cancer, including intramucosal carcinoma.

History of histologically or radiographically confirmed inflammatory bowel disease (ulcerative colitis or Crohn's disease).

History of large bowel resection.

Weight move than 150% of desirable weight according to the 1983 Metropolitan Life Insurance Tables.

Use of lipid-lowering drugs in pharmacologic doses in the last month.

Major life-limiting conditions reducing likelihood of completing 4-year follow-up.

Already consuming a dietary pattern similar to the intervention eating plan.

Any dietary practice, behavior, or attitude that would substantially limit adherence to the intervention program.

Participation in other clinical studies that may interfere with participation in the PPT.

Unable or unwilling to sign informed consent form.

Found to be unreliable and uncooperative providers of dietary information during the pre-randomization period.

Able to give reasonable assurance of remaining in the Clinical Center area for duration of the study.

  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00339625

United States, Maryland
National Cancer Institute (NCI), 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
National Cancer Institute (NCI)
Principal Investigator: Gwen A Murphy National Cancer Institute (NCI)
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: National Cancer Institute (NCI) Identifier: NCT00339625     History of Changes
Other Study ID Numbers: 9999910159
Study First Received: June 19, 2006
Last Updated: May 12, 2017

Keywords provided by National Institutes of Health Clinical Center (CC):

Additional relevant MeSH terms:
Pathological Conditions, Anatomical
Neoplasms, Glandular and Epithelial
Neoplasms by Histologic Type
Neoplasms processed this record on May 22, 2017