The efficacy and safety of panitumumab (Vectibix) in the routine clinical setting will be studied.

Specifically, information will be collected on the following as events of interest: skin disorders, interstitial lung disease, infusion reactions, electrolyte abnormalities, and cardiac disorders.

The efficacy and safety of panitumumab (Vectibix) in the routine clinical setting will be studied.

Participants of this surveillance will be patients with unresectable, advanced or recurrent colorectal cancer with the wild-type KRAS gene. The planned sample size is 2,000 patients.

The usual adult dosage is 6 mg/kg of panitumumab given by intravenous drip infusion over a 60-minute period once every 2 weeks. The dosage may also be reduced as needed, depending on the patient's condition.

Inclusion Criteria:

• Unresectable, advanced or recurrent colorectal cancer with wild-type KRAS gene

Exclusion Criteria:

• Patients with a medical history of severe hypersensitivity to any of the ingredients of Vectibix

Unresectable, advanced or recurrent colorectal cancer with wild-type KRAS gene

The first study related publication will be a multi-center publication submitted within 24 months after conclusion or termination of a study at all sites. After such multi site publication, all proposed site publications and presentations will be submitted to sponsor for review 60 days in advance of publication. Site will remove Sponsor confidential information unrelated to study results. Sponsor can delay a proposed publication for another 60 days to preserve intellectual property.