Although patients of colorectal cancer use Traditional Chinese Medicine (TCM) herbal therapy extensively in China, no strong evidence exists to demonstrate the safety and survival outcomes of TCM herbal therapy combined with conventional western medicine for treatment of this disease. The purpose of this multi-center perspective cohort study is to evaluate the relationship between TCM herbal therapy and survival outcomes in patients with advanced colorectal cancer.

Inclusion Criteria:

• histologically confirmed adenocarcinoma of the colon or rectum
• TNM classification of stage IV disease according to American Joint Committee on Cancer
• Between 18 and 80 years old
• Progression or inability undergone conventional chemotherapy (Conventional chemotherapy regimen containing fluorouracil, oxaliplatin, irinotecan based chemotherapy, and all the above regimen should be used before)
• Expected survival time is over 3 months
• Signed informed consent

Exclusion Criteria:

• serious non-malignant diseases such as heart, renal, and hepatic illnesses
• the presence of other types of malignancies
• The patients can not take medicine for intestinal obstruction

the patients with advanced colorectal cancer and the tumor progressed after conventional chemotherapy