ABSTRACT
Targeted monoclonal antibodies have become an important therapeutic option for patients with cancer. Cetuximab, a chimeric mouse-human (30:70) immunoglobulin G1 monoclonal antibody against epidermal growth factor receptor, has been approved by the US Food and Drug Administration for the treatment of head and neck and metastatic colorectal cancer (mCRC). Severe (grade 3/4) hypersensitivity-infusion reactions (HIRs) occur in 2-3% of the patients, with fatal outcomes in 0.1%. It is recommended that patients showing severe HIRs to cetuximab should avoid further exposure to it, but in some cases there is no alternative treatment. Two options are currently available for patients with HIRs to cetuximab: desensitization protocol and panitumumab. We describe here two patients with mCRC who successfully underwent a cetuximab desensitization protocol following a severe HIR to cetuximab.