Bevacizumab beyond progression has been proven to be safe in the community setting (BRiTE) and in the post-marketing study (BEAT), and confirmed its efficacy and safety in the first line with all regimens of chemotherapy. A total of 1,953 patients were treated in BRiTE. At median follow-up of 17.5 mo, there were 1,369 1st PD and 839 deaths. Among patients with 1st PD, 65.2% received any 2nd-line chemotherapy, 34.8% received cetuximab, and 53.8% received BBP. In a multivariate analysis, Bevacizumab beyond first progression and exposure to any 2nd-line chemotherapy were independently associated with increased overall survival (both p < 0.0001). Bevacizumab beyond progression appears to be associated with longer overall in BRiTE.

The investigators planned a prospective study to prove this phenomenon of bevacizumab beyond progression.

Patients should have been treated with bevacizumab plus chemotherapy as a 1st line treatment, and after 1st progression, these patients will be accrued in this study of bevacizumab plus chemotherapy as a 2nd line treatment, and the combined chemotherapy will be chosen by physician's decision in consider with previous chemotherapy.

Inclusion Criteria:

• Histologically documented colorectal adenocarcinoma
• Progression during first-line bevacizumab containing chemotherapy within 3 months
• No serious toxicity to bevacizumab of 1st line treatment
• Unresectable metastases
• Uni-dimensional measurable lesion(s) by RECIST
• Age over 18 years old
• ECOG 0-2
• Adequate organ functions by clinical laboratory exams

Exclusion Criteria:

• Other tumor type than adenocarcinoma
• CNS metastases
• GI bleeding
• Hypersensitivity to any of chemotherapeutic agents
• Prior use of cetuximab or other targeted agents other than bevacizumab
• Major surgery within 6 weeks
• Other serious illness