Inclusion Criteria:

- Histologically proven diagnosis of adenocarcinoma of the stomach (including
adenocarcinoma of the gastroesophageal junction)

- Stage III or Stage IV disease, according to American Joint Committee on Cancer
criteria

- Patients with UGT1A1*28 genotype 6/6 or 6/7

- Performance Status of 0-2 on the Eastern Cooperative Oncology Group (ECOG)
performance status Scale

- Previous adjuvant or pre-operative chemotherapy without containing irinotecan or
platinum at least 6 months before enrollment

- Adequate organ function including the following:

Bone marrow: absolute neutrophil count (ANC) >or equal to 1.5 * 109/L, platelets >or equal
to 100 *109/L, hemoglobin > or equal to 10 g/dL.

Hepatic: bilirubin < or equal to 1.5 x ULN; alkaline phosphatase, aspartate transaminase
(AST) and alanine transaminase (ALT) < or equal to 3 x ULN (alkaline phosphatase, AST, ALT
minor or equal to 5 x ULN is acceptable if liver has tumor involvement), serum albumin >
or equal to3g/dL.

Renal: Calculated creatinine clearance major or equal to 60 ml/min (using the standard
Cockcroft-Gault formula).

Exclusion Criteria:

- No Prior palliative chemotherapy for advanced disease

- Previous radiation therapy is allowed but should have been limited and must not have
included whole pelvis radiation. Patients must have recovered from the toxic effects
of the treatment prior to study enrollment (except for alopecia). Prior radiotherapy
must be completed at least 30 days before study enrollment

- Known or suspected brain metastasis

- Second primary malignancy