Cetuximab Maintenance Treatment Versus Continuation After Induction Therapy in mCRC

Before the start of induction therapy:

Inclusion Criteria:

* Histological proof of colorectal cancer (in case of a single metastasis, histological or cytological proof of this lesion should be obtained);
* Distant metastases which are either technically unresectable or no chance to reach NED (patients with only local recurrence are not eligible);
* Measurable disease (\> 1 cm on spiral CT scan or \> 2 cm on chest X-ray; liver ultrasound is not allowed). Serum CEA may not be used as a parameter for disease evaluation;
* Ongoing or planned first line induction therapy with 8 cycles of FOLFIRI or mFOLFOX6.

Exclusion criteria

* Prior adjuvant treatment for stage II/III colorectal cancer ending within 6 months before the start of induction treatment
* Any prior adjuvant treatment after resection of distant metastases
* Previous systemic treatment for advanced disease
* RAS mutant mCRC

At randomisation:

Inclusion criteria:

* WHO performance status 0-1 (Karnofsky PS \> 70%);
* Disease evaluation with proven SD, PR or CR according to RECIST after 8 cycles of FOLFIRI or mFOLFOX6;
* Laboratory values obtained ≤ 2 weeks prior to randomisation: adequate bone marrow function (Hb \> 8.0 mmol/L, absolute neutrophil count \> 1.5 x 109/L, platelets \> 100 x 109/L), renal function (serum creatinine ≤ 1.5x ULN and creatinine clearance, Cockroft formula, \> 30 ml/min), liver function (serum bilirubin ≤ 2 x ULN, serum transaminases ≤ 3 x ULN without presence of liver metastases or ≤ 5x ULN with presence of liver metastases);
* Life expectancy \> 24 weeks;
* Age: 18-75 years;
* Negative pregnancy test in women with childbearing potential;
* Expected adequacy of follow-up;
* Institutional Review Board approval;
* Written informed consent Exclusion criteria
* Chronic active infection;
* Any other concurrent severe or uncontrolled disease preventing the safe administration of study drugs;