Inclusion Criteria:

- Written Informed consent

- Male or female patients >=18 years old

- Histologically or cytologically confirmed diagnosis of adenocarcinoma

- No previous treatment is allowed including chemotherapy, radiotherapy,immunotherapy
or others.

- In case the patient received adjuvant therapy before, enrollment is allowed if the
adjuvant therapy does not contain L-OHP or S-1 and at the same time, the last day of
chemotherapy is ≥180 days before screening.

- Target lesion more than 1cm in diameter by enhanced CT or MRI 21 days before
enrollment

- The laboratory parameter meets the following criteria 7 days before enrollment

- Hemoglobin ≥90g/L

- Absolute neutrophil count≥1.5×10^9/L, platelets 100×10^9/L；

- ALT and AST≤2.5 ULN(in case of the patients with liver metastasis,ALT and
AST≤5.0 ULN)

- ALP ≤2.5 ULN (in case of the patients with liver metastasis,≤5.0 ULN)

- Total Serum bilirubin ≤1.5 ULN

- Serum creatinine ≤1.0 ULN

- serum albumin(ALB)≥30g/L；

- can tolerate oral drug administration；

- KPS ≥70

- Estimated survival ≥90 days

- Women of childbearing potential must have a negative serum or urine pregnancy test
within 7 days of enrollment and must be willing to use adequate methods of
contraception during the study and for 30 days after last study durg administration.

Exclusion Criteria:

- Known sensitivity to 5-HT3 antagonist and hypersensitivity to the other treatment
agents including irinotecan, cisplatin and octreotide lar

- Any participation in trials simultaneously or 4 weeks before screening.

- 15 days prior to enrollment, received a blood transfusion, blood products and
hematopoietic growth factors such as G-CSF.

- Undergone major surgery ≤ 4 weeks prior to starting study drug or who have not
recovered from side effects of such surgery.

- Uncontrolled severe diarrhea

- Uncontrolled active infection (fever ≥38 degrees due to infection)

- S-1 oral drug administration difficulty due to difficulty swallowing, complete or
incomplete digestive tract obstruction, gastrointestinal active bleeding,
perforation;

- severe hepatopathy including active hepatitis and hepatic cirrhosis, renal
dysfunction, severe pulmonary diseases including interstitial pneumonia, pulmonary
fibrosis and severe pulmonary emphysema, uncontrolled diabetes, hypertension and
other chronic systematic diseases.

- Chronic treatment with steroids.(In case of the patients with short-term use of
steroids, the enrollment is permitted if the administration is stopped 2 weeks before
screening.)

- confirmed or suspected CNS metastasis

- the history of peripheral nervous system impairment, obvious mental disorder or CNS
impairment

- clinically significant heart disease, including congestive heart failure, symptomatic
coronal heart disease, arrythmia uncontrolled by medication and acute myocardial
infarction or cardiac insufficiency within 6 months before screening

- Drainage of pleural effusion, peritoneal effusion and pericardial effusion

- pregnant women or women in lactation period

- Fertile male or women of child-bearing potential refuse to take highly effective
methods of birth control

- Incidence of other second primary malignant tumors within 5 years, except for cured
basal cell carcinoma and cervical carcinoma in situ.

- patients of legal incapacity or who have the potential of influence the whole trial
due to medical or ethic reasons.

- Other patients who are not eligible to the trial under investigators' discretion