Docetaxel + Oxaliplatin + S-1 in Potentially Operable Gastric or Gastroesophageal Adenocarcinoma

Inclusion criteria: * Patients with histologically confirmed, newly diagnosed, localized gastric or gastro-esophageal adenocarcinoma, that is considered operable. * The bulk of disease must be localized in the stomach, although the gastroesophageal junction may be involved. * Patients with T3 or T4 carcinoma without (N0) and T2 or T3 or T4 with regional lymph node involvement assessed by EUS, no peritoneal seeding suspected on abdomen-pelvic CT or confirmed by laparoscopy. * Performance status 0-1 in ECOG scale * Adequate haematological function and liver and kidney function within 7 days prior to enrollment: * Absolute neutrophil count \> or = 1.5 x 10\^9/L * Platelets \> or = 100 x 10\^9/L * Haemoglobin \> 10 g/dl * Calculated creatinine clearance \> or = 60 ml/min * Total bilirubin \< or = 3 x UNL * GOT and GPT \< or = 3 x UNL Exclusion Criteria * Previous surgery on primary tumour * Prior palliative surgery (open and closure, passage operation) * Any other type of tumour (e.g. leiomyosarcoma, lymphoma) or a secondary malignancy, excepting basal cell skin carcinoma or basal cell carcinoma in situ of the cervix which have already been successfully treated * Distant metastases (M1) including distant nodal Groups (Retropancreatic, para-aortic, portal, retroperitoneal, mesenteric node) * Any previous palliative, adjuvant or neoadjuvant chemotherapy and/or radiotherapy * Simultaneous therapy with other anti-tumour drugs * Ileus, chronic inflammatory intestinal disease or extensive resection of the small intestine and other disorders which limit drug resorption. This includes gastric dumping syndrome, indications of accelerated passage through the small intestine, indications of resorption disorders after intestinal surgery * Evidence of gastric outlet obstruction and /or severe tumor hemorrhage * Other anamnestic reaction, serious illness or other medical conditions: * Unstable, persistent cardiac disease despite medicinal treatment, myocardial infarction within 6 months before the start of the trial * Chronic diarrhoea * Neurological or psychological disorders including dementia and seizures * Active, non-controllable infection or sepsis * Actively disseminated intravascular coagulation * Symptomatic peripheral neuropathy NCI CTC version 3.0 grade \> or = 1 * Hypersensitivity to study drugs * Patients under anticoagulant therapy with warfarin or other coumarines are excluded from participation. * Pregnant or lactating (in case of potentially childbearing woman, pregnancy test is positive) * Patients of child-bearing age or the potential to father a child who refuse to use adequate contraception * Drug, substance or alcohol abuse The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.