Cetuximab for colon cancer, side effects and benefits by Ray Sahelian, M.D.
April 3 2015


Erbitux ( cetuximab ) is a pharmaceutical drug used to treat patients with advanced colon cancer that has spread to other parts of the body. Cetuximab is the first monoclonal antibody approved to treat this type of cancer and is indicated as a combination treatment to be given intravenously with irinotecan, another drug approved to fight colorectal cancer, or alone if patients cannot tolerate irinotecan.


Cetuximab mechanism of action
The role of epidermal growth factor receptor (EGFR)-driven signaling in different stages of colorectal carcinogenesis, as well in the acquisition of therapy resistance, has been established. Multiple strategies have been developed for the therapeutic targeting of EGFR. Cetuximab is a chimeric monoclonal antibody selective for EGFR with efficacy alone or in combination with irinotecan in the treatment of metastatic colorectal cancer patients, who have progressed to using irinotecan-containing chemotherapy. The combination of cetuximab with standard chemotherapy regimens such as irinotecan/ 5-FU/folinic acid (FA) or oxaliplatin/5-FU/FA are currently being investigated in Phase III trials for chemotherapy-naive patients with metastatic colorectal cancer.


Cetuximab side effect
A 71-year-old man exhibited an acute acneiform rash affecting the face and the upper trunk about 2 weeks after starting cetuximab, an epidermal growth factor (EGF) receptor antagonist treatment for metastatic colon cancer. The skin eruption faded after stopping cetuximab and applying topical corticosteroids. The reexposure to cetuximab 3 weeks later provoked a more extended relapse of the skin rash, which then clinically and histologically corresponded to transient acantholytic dermatosis . While the acneiform cutaneous side effects of the EGF receptor antagonists are interpreted as a result of the direct interference with pilosebaceous follicle homeostasis, in this case an acrosyringium-related pathogenesis might be postulated. Applying topical corticosteroids and emollients, the cetuximab therapy could be pursued.


Clin Med Insights Oncol. 2014. Case Report About Fatal or Near-Fatal Hypersensitivity Reactions to Cetuximab: Anticetuximab IgE as a Valuable Screening Test. Hypersensitivity reactions are a classic side effect of cetuximab. We report the cases of three patients who developed life-threatening hypersensitivity to cetuximab, which could have been predicted by assessing the concentration of serum anticetuximab immunoglobulin (Ig)E. The anticetuximab IgE concentration could be an interesting test to predict which patients are at risk of experiencing severe hypersensitivity reactions to cetuximab.