Inclusion Criteria:

          -  Signed informed consent.

          -  Male and female patients aged from 18 to 75 years

          -  Histologically confirmed Colorectal cancer,Esophagus squamous cell carcinoma, biliary
             tract cancer, and digestive system tumor beyond CRC and GC&GEJA with the following
             specifications:

               -  genetic testing conformed KRAS/NRAS/BRAF all wild type for colorectal cancer

               -  Detection of a carcinoma with HER2 3+ (IHC) or HER2 2+ (IHC) with amplification
                  proven by fluorescence in situ hybridization(FISH), silver in situ
                  hybridization（SISH） or chromogenic in situ hybridization（CISH） using gastric
                  cancer criteria by an accredited local pathologist.

               -  Relapse or metastatic diseases, at least one measurable lesion according to
                  RECIST 1.1, anticipated survival ≥ 12 weeks.

               -  ECOG Performance status 0-1.

               -  Patients who failed at least first line systemic therapy.

               -  Adequate organ function as determined by the following laboratory results:

               -  Absolute neutrophil count ≥1500 cells/mm3,

               -  Platelet count ≥ 90,000 cells/mm3,

               -  Hemoglobin ≥9.0 g/dL

               -  Total bilirubin ≤ 1.5 upper limit of normal (ULN).

               -  serum glutamate oxaloacetate transaminase(SGOT,AST), serum glutamate pyruvate
                  transaminase(SGPT,ALT) < 2.5 ULN without liver metastases; < 5 ULN with liver
                  metastases.

               -  serum creatinine < 1.5

               -  ULN OR creatinine clearance ≥ 40 mL/ min.

          -  If able to reproduce, patients must be willing to use highly effective methods of
             contraception during treatment and for 7 months after the end of treatment.

        Exclusion Criteria:

          -  Known hypersensitivity against treatment regimen.

          -  Baseline left ventricular ejection fraction(LVEF) < 50% (measured by echocardiography
             or MUGA).

          -  Previous anti-her treatment.

          -  Immune therapy, biological therapy or any participation in clinical trial in previous
             two weeks.

          -  Surgery and not recovered in previous three weeks

          -  Clinical evidence of brain metastases, or uncontrolled epilepsy.

          -  Serious uncontrolled systemic intercurrent illness, e.g. infections or poorly
             controlled diabetes.

          -  Other malignancy within the last 5 years, except for carcinoma in situ of the cervix,
             or basal cell carcinoma.

          -  Clinically significant active coronary heart disease, cardiomyopathy or congestive
             heart failure, New York Heart Association(NYHA) III-IV; poorly controlled hypertension
             (systolic BP > 180 mmHg or diastolic BP > 100 mmHg); clinically significant valvular
             heart disease; unstable angina pectoris, myocardial infarction or high risk
             uncontrollable arrhythmias.

          -  Long term or high dose corticosteroids administration ( inhalation or short term oral
             administration for antiemesis and orexigenic is allowed)

          -  Patients of legally incapacity or of medical and ethical reasons not fit for study.

          -  Pregnant or lactating, or intending to become pregnant during the study.

          -  Jaundice, ascites, and / or alkaline phosphatase ≥3 × ULN; and / or ≥3 grade (CTC-AE)
             of persistent proteinuria, urinary protein / creatinine ratio> 3.5g / 24 hours or
             renal failure need blood or peritoneal dialysis.

          -  Presence of > grade 2(CTC-AE) persistent infection; unhealed wounds, ulcer or
             fracture, or patients with a history of organ transplant.

          -  Evidence of coagulation disorders. Like presence ≥grade 3 (CTC-AE) bleeding events.

          -  Known HIV or hepatitis B virus(HBV), hepatitis C virus(HCV) infection.

          -  Any > grade 1 unresolved toxicity due to previous treatment (CTC-AE), except for
             alopecia, anemia and hypothyroidism).

          -  Not suitable for the study evaluated by investigators

          -  Known dihydropyrimidine dehydrogenase (DPD) deficiency.

          -  History of exposure to the following cumulative doses of anthracyclines:

               -  Doxorubicin > 500 mg/m2 OR Epirubicin > 720 mg/m2.

                    -  If another anthracycline or more than one anthracycline has been used, then
                       the cumulative dose must not exceed the equivalent of 500 mg/m2 doxorubicin.