4616 Background: Our previous study of Gem with sandwich 5FU-3DRT for LAPC was encouraging (Br J Cancer 2007: 97, 464–471). Gem-Ox has higher response rate than Gem, improved progression free survival (PFS) but not overall survival (OS). Its use in LAPC may improve local control (LC) and delay systemic spread. GFG is a study of induction (ind) Gem-Ox, then 5FU-3DRT, then consolidation (con) Gem-Ox. Primary outcome is feasibility using proportion of patients (pts) receiving > 80% planned dose for each component. Secondary outcomes are safety, activity and QOL. Methods: Pts with previously untreated inoperable LAPC, M0, measurable disease, ECOG 0–2 were given Gem (1000mg/m2 d1 + d15 q28), Ox (100mg/m2 d2 + d16 q28) in both ind (1 cycle) & con (3 cycles), & 5FU 200mg/m2/d over 6 weeks during RT of 54Gy in 30 fractions of 1.8Gy. Results: 48 pts were enrolled, median age 61y (44–81y), PS 0/1=96%, regional lymph nodes=44%, T4=46%. Worst grade (G) for anaemia (10%); fatigue, nausea (8%); diarrhoea, vomiting, neutropenia, infection (4%); stomatitis, anorexia (2%) was G3. Thrombocytopenia was G3=2% G4=2%; liver function was G3=23% G4=6%; late radiation toxicity was G3=2% G4=2% (both gastric bleeding). Half of all pts completed all planned cycles (24 pts); 29% of pts received >80% of all treatment (14 pts); 70% of pts received >80% of all chemoradiation (33 pts). Pts ceased treatment for toxicity (16%), PD (21%) or doctor/pt preference (4/2%). Global QOL did not significantly change from baseline. Median duration of LC, PFS, OS were 15.8, 9.9, 15.4m at median follow up of 29.7m. Exploratory analysis of age, disease stage, PS, CA19–9 or WCC found no univariate predictors of PFS or treatment completion. 8/48 pts survived >24m. Conclusions: Compared to our previous study using the same radiation schedule, addition of oxaliplatin was associated with improved LC, PFS & OS (prev. 11.9, 7.1 & 11.7m) without significant offset by toxicity. The extended duration of LC and a subset who had a very prolonged benefit may be due to patient selection but equally may suggest an incremental benefit from more intensive systemic therapy requiring further study in controlled trials. [Table: see text]