Phase II:

Primary objective: to select one of the 2 test arms (docetaxel with cisplatin, docetaxel with cisplatin and 5-FU), based primarily on complete responses, to advance to a phase III survival comparison against the CDDP + 5-FU control arm.

Secondary objective: to evaluate the quantitative and qualitative safety profile of the 2 test groups.

Phase III:

Primary objective: to detect a statistically significant increase in time to progression (TTP) for the test arm (docetaxel plus cisplatin and 5-FU) relative to the control arm (cisplatin plus 5-FU).

Main secondary objective: to detect a statistically significant increase in overall survival (OS) for the test arm (docetaxel plus cisplatin and 5-FU) relative to the control arm (cisplatin plus 5-FU).

Other secondary objectives: to compare response rates, time to treatment failure, duration of response, safety profiles, quality of life and disease-related symptoms.Socio-economic data will be collected in order to be able to perform an analysis by country when necessary.

Inclusion Criteria:

• Patient's consent form obtained, signed and dated before beginning specific protocol procedures.
• Gastric adenocarcinoma including adenocarcinoma of the esophagogastric junction, histologically proven.
• Measurable and/or evaluable metastatic disease; if a single metastatic lesion is the only manifestation of the disease, cytology or histology is mandatory. Locally recurrent disease is accepted provided that there is at least one measurable lesion (e.g. lymph node).
• Performance status Karnofsky index > 70%.
• Life expectancy of more than 3 months.
• Adequate haematological and biochemistry parameters
• No prior palliative chemotherapy, previous adjuvant (and/or neo-adjuvant) chemotherapy is allowed if more than 12 months has elapsed between the end of adjuvant (or neo-adjuvant) therapy and first relapse.

Exclusion Criteria:

• Pregnant or lactating women.
• Patients (M/F) with reproductive potential not implementing adequate contraceptive measures.
• Other tumor type than adenocarcinoma (leiomyosarcoma ; lymphoma).
• Any prior palliative chemotherapy. Prior adjuvant (and/or neo-adjuvant) chemotherapy with a first relapse within 12 months from the end of adjuvant (or neo-adjuvant).
• Prior treatment with taxanes. Prior CDDP as adjuvant (and/or neo-adjuvant) chemotherapy with cumulative dose > 300 mg/m².