It is the goal of this study to measure estrogen receptor (ER) levels in colonic mucosa utilizing an immunoassay technique that is based on direct antigenic recognition rather than steroid binding activity. Use of this methodology will overcome some of the problems associated with measuring ER in colorectal adenomas or adenocarcinomas encountered in previous studies. Tumor or biopsy tissue will be obtained from patients who are undergoing colonscopy at the Endoscopy Clinic of the Diagnostics Gastroenterology Unit at Yale-New Haven Hospital (YNNH) and patients being treated surgically for adenocarcinoma of the colon or rectum at YNNH. These subjects will be divided into three groups for purposes of analysis: 1) persons with pathologically diagnosed malignant disease; 2) persons with pathologically diagnosed precursor lesions (adenomatous polyps greater than 1 cm in size); and 3) persons with non-precursor lesions (small adenomatous polyps or hyperplasitc polyps) or other diseases for which they are undergoing colonoscopy or surgery, and persons found to have normal GI epithelium. The information obtained from the ER assay will be analyzed for correlation with presence of malignant or precursor lesions and other medical parameters that are associated with risk for this disease. This study will provide us with information to evaluate the immunoassay procedure as a valid method for measuring ER levels in colonic mucosa and to establish baseline values for this receptor in malignant and non-malignant disease. This information can then be used to formulate hypothesis to be tested in larger epidemiologic studies.
