1. To evaluate efficacy, safety, and feasibility of maintenance therapy with Cetuximab combined with irinotecan or fluorouracil after Cetuximab plus irinotecan and fluorouracil(FOLFIRI) in patients with incurable colorectal cancer.
2. The relevant phase III studies reported that the progression free-survival of cetuximab combined with FOLFIRI in advanced colorectal cancer was 4.3 months up to 6.8 months.

This study assumed that the progression free-survival was 5.1 months which was not inferior to the continuous chemotherapy

Inclusion Criteria:

1. Patients aged ≥18 years with histologically confirmed metastatic colorectal cancer
2. Eastern Cooperative Oncology Group performance status ≤2 and
3. life expectancy of >3 months were enrolled.
4. All patients had to have at least one measurable lesion according to the Response Evaluation Criteria in Solid Tumors (RECIST, version 1.1)
5. None was previous exposure to Cetuximab or irinotecan .
6. Patients had to have adequate haematological (absolute neutrophil count >1.5 × 109/l; platelet count >100 × 109/l; haemoglobin >9 g/dl), hepatic [total bilirubin <1.5 × the upper limit of normal (ULN); alanine aminotransferase and aspartate aminotransferase <2.5 × ULN, or <5 × ULN in the case of hepatic metastases or <10 × ULN in the case of osseous metastases; alkaline phosphatase <2.5 × ULN, or <5 × ULN or <10 × ULN in the case of hepatic or osseous metastases, respectively] and renal function (creatinine clearance ≥60 ml/min)
7. All RAS were wildtype. -

Exclusion Criteria:

1. Pregnant or breast-feeding women;
2. Clinically significant cardiac disease;
3. Lack of physical integrity of the upper gastrointestinal tract;
4. History of other malignancy;
5. Central nervous system metastases. -