To decide maximum tolerated dose and/or recommended dose of Gemcitabine or S-1 adjuvant therapy after hemihepatectomy

There is no standard adjuvant therapy after liver hemi-hepatectomy due to bile duct cancer, because of high surgical morbidity ratio and high adverse event ratio of adjuvant therapy. For example, our preliminary results showed that regular gemcitabine administration (1000mg/m2, day1, 8, 15 every 4 weeks) after hemihepatectomy was too toxic and induced severe leukocytopenia and/or thrombocytopenia. Herein, we planned this study to decide more safety adjuvant protocol(recommend dose) for gemcitabine and S-1 after hemihepatectomy using continual reassessment method analysis. In this study, we decided that tolerable ratio of dose-limiting toxicity would be less than 10%.

Inclusion Criteria:

1. Biliary tract cancer (>= UICC Stage IB)
2. R0 or R1 resection due to biliary tract cancer (BTC)
3. ECOG performance status must be 0 or 1
4. The patient underwent no other treatment than surgery for BTC
5. Neutrophil must be over 1500/μl, platelet must be over 100,000/μl, AST and ALT must be less than five times the normal limit, total bilirubin must be less than three times the normal limit, and creatinin must be less than 1.2 mg/dl.
6. The patient can intake drugs per os.
7. From 4 to 12 weeks after the surgery
8. Written informed consent

Exclusion Criteria:

1. Existence of active double cancer
2. The patient suffered from severe drug allergy
3. Sever complications (interstitial pneumonia, heart failure, renal failure, liver failure, ileus, incontrollable diabetes mellitus, and so on)
4. Any active infections exist.
5. Pregnancy
6. Severe mental disorder
7. Others