Clinical Prevention Trials: Organ Site-Specific Investigations: Colon and Other Gastrointestinal Cancers The Polyp Prevention Trial-Continued Follow-up Study: No effect of a low fat, high fiber, high fruit and vegetable diet on adenoma recurrence eight years after randomization. Elaine Lanza, Binbing Yu, Paul S. Albert, Bette Caan, James R. Marshall, Peter Lance, Electra Paskett, Joel Weissfeld, Martha Slattery, Randall Burt, Frank Iber, Moshe Shike, James W. Kikendall, Robert Schoen, Brenda Brewer and Arthur Schatzkin National Cancer Institute, Bethesda, MD; Information Management Services, Rockvile, MD; Kaiser Foundation Research Institute, Oakland, CA; Roswell Park Cancer Institute, Buffalo, NY; Arizona Cancer Center, Tuscon, AZ; Ohio State Cancer Center, Columbus, OH; University of Pittsburgh, Pittsburgh, PA; University of Utah, Salt Lake City, UT; Edward Hines, Jr., Hospital, Veterans Affairs Medical Center, Hines, IL; Memorial Sloan-Kettering Cancer Center, New York, NY; Walter Reed Army Medical Center, Washington DC, DC; Westat, Rockville, MD Abstract #B147 The Polyp Prevention Trial (PPT) was a multi-center randomized clinical trial to evaluate the effects of a high-fiber (18 g/1000 kilocalories [kcal]), high-fruit and vegetable (3.5 servings/1000 kcal), low-fat (20% of total energy) diet on the recurrence of adenomatous polyps in the large bowel. Although intervention participants reported significantly reduced intake of dietary fat and increased fiber and fruit and vegetable, their risk of recurrent adenomas was not significantly different than that for the controls (N Engl J Med 2000;342:1149-1155). Since the PPT intervention lasted only 4 years, it is possible participants need to be followed for a longer period of time before treatment differences in adenoma recurrence emerge, particularly if diet affects early events in the neoplastic process. The PPT-Continued Follow-up Study (PPT-CFS) was a post-intervention observation of PPT participants for an additional five years from the completion of the trial. Of the 1905 PPT participants, 1192 consented to participate in the PPT-CFS and confirmed colonoscopy reports were obtained on 801 participants. The mean time between the main trial endpoint colonoscopy and the first colonoscopy in the PPT-CFS was 3.94 years.The baseline characteristics of 405 intervention participants and 396 control participants in the PPT-CFS were quite similar. While the intervention group significantly changed each of their dietary goals during the PPT, during the PPT-CFS the trend for each dietary goal was significantly reversed. Even though the intervention group participants increased their fat and decreased their intake of fiber and fruits & vegetables during the PPT-CFS, they did not go back to their pre-randomization baseline diet (p<0.001 from pair t-tests) and each of the three dietary goals was still significantly different than the controls during the PPT-CFS (p<0.001 from t-tests). As the CFS participants are a subset of the people in the PPT study, the non-participants might not be missing completely at random. Therefore, a multiple imputation method was used to correct the potential selection bias. The relative risk (95% C.I.) of recurrent adenoma in the intervention group compared to the control group was 0.96 (0.80, 1.16). There were also no significant differences in the relative risk for a recurrence of an advanced adenoma in the intervention group compared to the control group was 1.04 (0.65, 1.65) and multiple adenomas 0.88 (0.64, 1.20). We also used a multiple imputation method to examine cumulative recurrence of adenomas at either T4 of the PPT or during the PPT-CFS. Comparing the intervention to the control group the relative risk (95% C.I.) of any adenoma recurrence was 0.99 (0.87, 1.11). This study failed to show an effect of a low fat, high fiber, high fruit and vegetable eating pattern on adenoma recurrence even with eight years of follow-up. Frontiers in Cancer Prevention Research, 11/06 Ann's NOTE: I just want to point out that the high consumption was 3.5 fruit or vegetable portions per day. The National Cancer Institute suggests a MINIMUM of 5 a day. How definitive can this be? Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.