Circulating Tumor Cells As A Surrogate For Treatment Response In Patients With Metastatic Pancreatic Adenocarcinoma.

318Background: The collection and enumeration of circulating tumor cells (CTCs) are feasible in metastatic breast, prostate and colorectal cancers. CTCs have diagnostic, prognostic and treatment monitoring implications, but have been challenging to detect in pancreatic cancer (PCa). We have proven feasibility of CTCs in PCa. This study is a pilot to assess use of CTCs as a surrogate for imaging response. Methods: Blood samples (7-10mL) from newly diagnosed metastatic PCa were collected within 1 month of treatment initiation (T0) and at repeat scan after 2mo of treatment (T1). Specimens were processed within 6 hours of collection. A UF developed microfluidic device was used to capture and identify EpCam+ CTCs. Isolated cells were verified as CTCs consistent with FDA-approved definitions (cytokeratin+, DAPI+, CD45-). CTC enumeration and changes were correlated with scan RECIST results at T0 and T1. The study was approved by the UF IRB. Results: A total of 16 patients had matched pair CTCs collected and anal...