Inclusion Criteria:

- presence of at least one measurable disease

- performance status of ECOG 0, 1

- age between 20 and 74 years at registration

- life expectancy of at least 12 weeks

- ability to take the oral study medication (TS-1)

- voluntarily signed the written informed consent form.

Exclusion Criteria:

- other malignancy with the exception of curative treated non-melanoma skin cancer or
cervical carcinoma in situ within 5 years prior to the entry of study

- previously received chemotherapy or therapy with systemic anti-tumor effect

- significant co-morbid medical conditions, including, but not limited to , heart
failure, renal failure, hepatic failure, hemorrhagic peptic ulcer, mechanical or
paralytic ileus, or poorly controlled diabetes

- fertile women of child-bearing potential unless using a reliable and appropriate
contraceptive method throughout the treatment period and for three months following
cessation of treatment

- Presence of mental disease or psychotic manifestation

- Participation in another clinical trial with any investigational drug within 30 days
prior to entry

- judged ineligible by physicians for participation in the study due to safety concern.