OBJECTIVES: EOX (epirubicin, oxaliplatin, Xeloda®) and FOLFOX4 (5-fluorouracil (5-FU), leucovorin, oxaliplatin) are the common chemotherapy regimens used in the treatment of advanced gastric cancer (aGC) in Hong Kong.  Previous clinical studies have shown the Xeloda®-based regimen, EOX, to be non-inferior to the 5-FU-based counterpart, FOLFOX4, in terms of efficacy.  This study aims to compare the costs of these therapies from both the healthcare and societal perspectives. METHODS: Thirty-seven patients were identified from the electronic records at a public tertiary hospital, with 26 and 11 received EOX and FOLFOX4 regimens respectively.  Healthcare cost refers to direct medical costs including drugs, clinic follow-up, hospitalization, diagnostic laboratories and radiographs.  Societal cost refers to indirect costs such as patient time and travel costs.  Cost items were further classified as "expected" or "unexpected".  All cost data was expressed in Hong Kong dollars (app. 10HKD = 1Euro). RESULTS: Patients in the EOX and FOLFOX4 arm received an average of 5.3 and 7.5 cycles of treatment respectively.  The Xeloda®-based regimen group had a higher expected medication cost when compared to the 5-FU-based treatment group ($5145.3 vs. $2515.3, p<0.001) but lower expected hospitalization costs ($600 vs. $9900, p<0.001) and associated time costs ($812.6 vs. $1197.3, p=0.001) due to fewer hospital bed-days required for delivery.  The total healthcare cost and total societal cost per patient was reduced by 59.3% ($58541.2 vs. $143914.1, p<0.001) and 42.6% ($8127.5 vs. $14151.3, p<0.001) respectively in the Xeloda®-based regimen group.  Sensitivity analyses based on full cycle regimen costs and net Xeloda® or 5-FU/leucovorin costs still showed EOX to be less costly than FOLFOX4. CONCLUSIONS: The Xeloda®-based regimen, EOX, was found to generate significant cost saving in both healthcare and societal perspectives.  Provided the similar efficacy between EOX and FOLFOX4 in aGC treatment, the Xeloda®-based therapy is more cost-effective and should be advocated when appropriate.