Abstract #1177 Randomized, placebo-controlled trial of 9-cis retinoic acid (9cRA) versus 13-cis retinoic acid (13cRA) plus alpha-tocopherol (AT) in the reversal of biomarkers of bronchial preneoplasia in former smokers. JM Kurie, R Lotan, JJ Lee, JS Lee, RC Morice, DD Liu, X-C Xu, FR Khuri, JY Ro, WN Hittelman, HA Fritsche, GL Walsh, D Minna, WK Hong MD Anderson Cancer Center, Houston, TX; National Cancer Center Hospital, Tokyo, Japan; Southwestern Medical Center, Dallas, TX Purpose: To investigate the efficacy of 9cRA versus 13cRA plus AT in the reversal of biomarkers of bronchial preneoplasia in former smokers. Method: Former smokers (smoked at least 20 pack-years and ceased smoking for at least 12 months) were randomized to 3 months of daily oral treatment with 9cRA (100mg), 13 cRA (1 mg/kg) plus AT (1200IU), or placebo. Participants underwent bronchoscopic evaluation with biopsies at 6 predetermined sites prior to treatment, after 3 months of treatment and 3 months following treatment cessation. Biopsies were evaluated for the presence of histologic abnormalities (squamous metaplasia or dysplasia) and loss of retinoic acid receptor-beta expression. Primary endpoint was reversal of retinoic acid receptor-beta over the three months of treatment. A total of 226 participants were randomized:177 of them have had both baseline and 3-month biopsies. Eleven participants dropped out due to treatment-related toxicity. Results: Using biopsy site as the analysis unit…,after adjusting for gender, smoking pack years, and squamous metaplasia, 9cRA significantly up-regulated retinoic acid receptor-beta expression compared to placebo whereas 13cRA +AT did not. Conclusion: 9cRA reversed biomarkers of bronchial preneoplasia in former smokers and should be evaluated in larger chemoprevention trials. 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.