Study of PG2 Injection for Improving Fatigue in Patients After Palliative Abdominal Surgery for Cancer

Inclusion Criteria: * Patients who have cancer and are scheduled for palliative abdominal surgery for cancer * Age \> 20 years older * Patients who signed the informed consent form Exclusion Criteria: * Patients, at screening, has levels greater than 2.5 times the upper limit of normal liver function of alanine aminotransferase or aspartate aminotransferase. * Patients has a severe renal impairment (defined as serum creatinine greater than 2 times the upper limit of normal or BUN greater than 2.5 times the upper limit of normal for range); or the subject is on dialysis. * Patients have ongoing infection, respiratory tract dysfunction, cardiac dysfunction or immune disorder that, in the opinion of the investigator, may interfere with conduct of the study. * Patients who are not suitable for undergoing surgery (e.g. congenital hemostatic disorders) by the investigator's judgment. * Patients have enrolled or have not yet completed other investigational drug trials within 1 month before screening. * Female patients are pregnant or breast-feeding. * Patients who require preoperative nutritional support * Patients with serious comorbidities (American Society of Anesthesiologists Risk Class of 4 or 5). * Patients who is unwilling or unable to answer the quality of life questionnaires i.e. the BFI-T and EORTC QLQ-C30.