The primary objectives is to test the efficacy of Adnab-9 stool testing in a population at high-risk for colorectal neoplasia and directly compare it to that of the FOBT and secondarily, identify the source of the Adnab-9 antigen to determine influences of diet and environment on its expression. The design is a prospective cross sectional (Part 1) and a case-control longitudinal follow-up study (Part 2) using a brief questionnaire to assess risk for cancer in a total of 2800 Part I patients will be enrolled designed to achieve a database of high risk individuals and measure fecal Adnab-9 levels before a clinically indicated colonoscopy is performed. The patients submit 4 FOBT cards in a routine manner by mail, 3 are used for the FOBT and stool is extracted from the last card for the Adnab-9 ELISA which is reported as OD/5ug protein/well. 100 Part 2 enrollees are then selected on the basis of positive fecal Adnab-9 test candidates matched with a like number of patients with negative stool results who have had their initial colonoscopy and who will have a 5-year follow-up colonoscopy. Detailed Adnab-9 testing (immunohistochemical Adnab-9 binding; blood biomarker estimations and Adnab-9 Western blotting) will be performed on various bodily fluids to perfect the method of testing and completion of the detailed questionnaire to check for reproducibility and interim lifestyle changes in these participants.
