229 Background: Gemcitabine and 5-fluorouracil (5-FU) with or without oxaliplatin are used to manage advanced or recurrent pancreatic cancer. Options are limited for patients who do not respond to these agents. This study determined the pattern of response to alternative agents using an in vitro chemotherapy assessment. Methods: From August 2006 to January 2010, 113 tumor specimens from pancreatic cancer patients were tested for response to gemcitabine, 5-FU, oxaliplatin, docetaxel, or irinotecan using an in vitro chemosensitivity assay (ChemoFx, Precision Therapeutics, Inc., Pittsburgh PA). Tumors were classified as sensitive or resistant based on in vitro dose response curves. Results: Thirty-five percent of tumors exhibited in vitro chemosensitivity to irinotecan, 23% to gemcitabine, 19% to 5-FU, 9% to oxaliplatin, and 8% to docetaxel. For tumors resistant to gemcitabine, 23% were sensitive to irinotecan, 6% (4/72) to 5-FU, 3% (2/68) to oxaliplatin, and 2% (1/64) to docetaxel (Table). Of the 68 tumors resistant to both gemcitabine and 5-FU, 11/59 (19%) were sensitive to irinotecan, 2/61 (3%) to oxaliplatin, and 0/57 (0%) to docetaxel. Forty-nine tumors were resistant to all tested agents. Conclusions: ChemoFx analysis of pancreatic cancer patient specimens indicates a high resistance rate to gemcitabine and 5-FU. The sensitivity of 19% of the gemcitabine/5-FU resistant specimens to irinotecan suggests that some patients who do not respond to standard therapy may respond to irinotecan. The potential of ChemoFx to identify the potentially most effective therapy in pancreatic cancer patients will be examined in future studies. [Table: see text] [Table: see text]
