e15079 Background: There are currently limited options for selecting an optimal treatment regimen for AGC patients. The Drug Response Indicator Test (DRIT) is a platform technology that provides a detailed profile of a patient's tumor response to commonly used chemotherapeutic drugs, as a basis for individualized treatment. Establishment of DRIT will allow physicians to choose effective drug treatments to improve the efficacy of cancer therapies on an individual basis. Methods: DRIT analysis is based on fluorescent dye-labeled monoclonal antibody staining followed by computer-assisted microscopy to measure expression levels in tumor sections. The interpretation of the Drug Response Indicator (DRI) expression levels result in classification of tumors as sensitive or resistant to treatment with a mechanistically related drug. Clinical outcomes are then analyzed with respect to the DRI data. This study utilized the following drug/DRI combinations: capecitabine, 5-flurouracil/thymidylate synthase; docetaxel, paclitaxel, abraxane/β-tubulin isoform III; gemcitabine/ribonucleotide reductase; platinum salts/ERCC-1; Irinotecan/Topoisomerase I. Results: DRIT retrospective studies were performed on a cohort of 33 consented patients (pts) receiving 55 treatments for AGC at UMGCC. This cohort included pts treated for rectal/colon, gastric, esophageal & pancreatic cancers. DRIT sensitivity was 0.96, positive predictive value 0.84, negative predictive value 0.67 and overall predictive accuracy 83 %. DRI expression level cut-off points indicating sensitivity or resistance to a specific treatment were derived from previous retrospective breast cancer studies using similar drug complements (abstract 6075 San Antonio Breast Conference 2008). Conclusions: This study indicates that DRIT can provide accurate prediction of treatment outcomes for individual AGC patients. DRI expression level cut-off points indicating sensitivity or resistance to a specific treatment may be applied to both breast cancer & AGC. DRIT will allow for tailoring of chemotherapy based on the specific biomarker expression within each patient's tumor tissue. [Table: see text]