The Efficacy and Safety of Nab-paclitaxel Plus S-1 in First-line Treatment of Advanced Biliary Tract Adenocarcinoma

Inclusion Criteria:

* Age, years: 18-70
* Histologically and cytologically confirmed advanced biliary tract adenocarcinoma, unresectable, measurable lesions according to RECIST criteria; ECOG score of 0-1; life expectancy ≥12 weeks;
* Untreated; more than 6 months after the last adjuvant chemotherapy (does not include taxanes and S1);
* Laboratory examination within 14 days before entering the study should meet following requirements:

ANC ≥ 1.5 x 10\^9/L; PLT ≥ 100 x 10\^9/L; Hb ≥ 90g/L (9g/dL); AST, ALT ≤ 2.5 x ULN (with no liver metastasis), ≤ 5 x ULN（with liver metastasis); creatinine ≤ 1.5 x ULN; TBIL ≤ 1.5 x ULN

* Both male and female subjects of potential fertility have to agree effective birth control during the entire study
* Informed consent

Exclusion Criteria:

* Concurrent other effective treatment (including radiotherapy)
* Resectable patients
* Allergy history to other drugs in the same class patients with pregnancy or lactation
* Known severe internal medical diseases
* Abnormal heart function or relevant history of myocardial infarction and severe arrhythmia
* Immunocompromised patients, such as HIV positive
* Uncontrollable mental illness
* Other conditions the researchers considered ineligible for the study