Practice Guideline Series

The epidermal growth factor receptor (EGFR) is often overexpressed or dysregulated in a variety of solid tumours, including gastrointestinal (GI) malignancies. Agents targeting the EGFR-mediated signalling pathway are increasingly part of the therapeutic armamentarium for the treatment of advanced lung, head-andneck, and colorectal carcinoma. The EGFR inhibitors (EGFRIs) approved in Canada include the tyrosine kinase inhibitors erlotinib and gefitinib (in selected cases), and the monoclonal antibodies (mAbs) panitumumab and cetuximab. Although EGFRIs have been proven effective in the treatment of a variety of malignancies, the entire class of agents is associated with a high prevalence of dermatologic side effects, most commonly skin rash. This reversible condition requires intervention in approximately one third of patients. A proactive, multidisciplinary approach to management can help to improve skin rash and optimize clinical outcomes by preventing EGFRI dose reduction or discontinuation. In addition, effective management and patient education may help to alleviate the significant social and emotional anxiety related to this manageable side effect, thus resulting in improved quality of life. The present article focuses on EGFR-targeted mAbs for the treatment of GI malignancy, addressing the pathophysiology, clinical presentation, and incidence of skin rash caused by this class of agents. Recommendations aimed at establishing a framework for consistent, proactive management of skin rash in the Canadian setting are presented.