Changing chemotherapy (C) with concurrent radiation (RT) followed by surgery after sub-optimal FDG-PET response to induction chemotherapy improves outcomes in locally advanced (LA) esophageal adenocarcinoma (EA).

4054 Background: Pre-operative CRT is a standard-of-care for LA EA. We showed that PET scan after induction C prior to CRT and surgery predicts outcomes (Cancer 118:2820; 2012). PET responders (PET+, defined as > 35% decrease in mSUV of tumor) had superior pathologic complete response (pCR) rates and progression-free survival (PFS) vs. PET non-responders (PET-, < 35% decrease). Some Pts with progression (PD) on PET after induction C had long-term overall survival (OS) when changed to alternative C during RT. Methods: We retrospectively reviewed all Pts with LA EA who received induction C and chemoRT prior to planned surgery. All Pts had PET scan before and after induction C. Results: 201 Pts were treated between 2002 to 2013, median age 62, 76% with uN+ disease. Induction C regimens included cisplatin/irinotecan (± bevacizumab on study) in 63% and carboplatin/paclitaxel in 29%. 113 Pts (56%) were PET+ and 88 (44%) were PET-. All PET+ received same C during RT. Of PET-, 49 (56%) continued with same C durin...